essay on rising pollution

Essay on Pollution for Students and Children

500+ words essay on pollution.

Pollution is a term which even kids are aware of these days. It has become so common that almost everyone acknowledges the fact that pollution is rising continuously. The term ‘pollution’ means the manifestation of any unsolicited foreign substance in something. When we talk about pollution on earth, we refer to the contamination that is happening of the natural resources by various pollutants . All this is mainly caused by human activities which harm the environment in ways more than one. Therefore, an urgent need has arisen to tackle this issue straightaway. That is to say, pollution is damaging our earth severely and we need to realize its effects and prevent this damage. In this essay on pollution, we will see what are the effects of pollution and how to reduce it.

Effects of Pollution

Pollution affects the quality of life more than one can imagine. It works in mysterious ways, sometimes which cannot be seen by the naked eye. However, it is very much present in the environment. For instance, you might not be able to see the natural gases present in the air, but they are still there. Similarly, the pollutants which are messing up the air and increasing the levels of carbon dioxide is very dangerous for humans. Increased level of carbon dioxide will lead to global warming .

Further, the water is polluted in the name of industrial development, religious practices and more will cause a shortage of drinking water. Without water, human life is not possible. Moreover, the way waste is dumped on the land eventually ends up in the soil and turns toxic. If land pollution keeps on happening at this rate, we won’t have fertile soil to grow our crops on. Therefore, serious measures must be taken to reduce pollution to the core.

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Types of Pollution

• Air Pollution
• Water Pollution
• Soil Pollution

How to Reduce Pollution?

After learning the harmful effects of pollution, one must get on the task of preventing or reducing pollution as soon as possible. To reduce air pollution, people should take public transport or carpool to reduce vehicular smoke. While it may be hard, avoiding firecrackers at festivals and celebrations can also cut down on air and noise pollution. Above all, we must adopt the habit of recycling. All the used plastic ends up in the oceans and land, which pollutes them.

So, remember to not dispose of them off after use, rather reuse them as long as you can. We must also encourage everyone to plant more trees which will absorb the harmful gases and make the air cleaner. When talking on a bigger level, the government must limit the usage of fertilizers to maintain the soil’s fertility. In addition, industries must be banned from dumping their waste into oceans and rivers, causing water pollution.

To sum it up, all types of pollution is hazardous and comes with grave consequences. Everyone must take a step towards change ranging from individuals to the industries. As tackling this problem calls for a joint effort, so we must join hands now. Moreover, the innocent lives of animals are being lost because of such human activities. So, all of us must take a stand and become a voice for the unheard in order to make this earth pollution-free.

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FAQs on Pollution

Q.1 What are the effects of pollution?

A.1 Pollution essentially affects the quality of human life. It degrades almost everything from the water we drink to the air we breathe. It damages the natural resources needed for a healthy life.

Q.2 How can one reduce pollution?

A.2 We must take individual steps to reduce pollution. People should decompose their waster mindfully, they should plant more trees. Further, one must always recycle what they can and make the earth greener.

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261 Pollution Essay Topics & Essay Examples

The problem of environmental pollution is one of the main subjects for discussion worldwide. Manufacturing, carbon emissions, plastic, etc., have an adverse impact on air, water, and soil entire the world. That is why it is crucial to understand the problem and develop solutions to mitigate our negative effects on Earth.

In this article, you will find interesting research questions about pollution, ideas for your argumentative and persuasive papers, and essay examples to inspire.

Keep reading!

💡 8 Tips for Writing Essays on Pollution

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There is a rising interest in ecological awareness and an overall building desire to move towards sustainable living within society. Thus, a pollution essay requires much more than merely outlining cause and effect occurrences.

Tackling a topic that should be both conscientious and demanding may be a difficult task, but with these few tips below, you can quickly address all pollution essay topics. Here are some ideas on how to make your assigned essay more comfortable to write:

Do your research beforehand. This action will help you start your bibliography, which you should begin by writing down every book and article you hope to use.

Additionally, doing so will help you better understand your subject and be more comfortable writing about it. Readers can always feel when writers are too vague because they want to avoid some aspects of a problem.

Introduce your issue from a historical viewpoint. You should explain the origin of your problem, outlining what changes began affecting the environment and why.

Doing so not only allows engaging your readers but also prevents needlessly confusing them by being evasive about your subject.

If some key terms and processes are not common knowledge, then you should explain them. Topics on pollution have tricky terminology, and you should allow your readers to read your essay while on the same level of knowledge as you.

For example, if you are writing about air pollution, then the terms you use may range from “particulate matter” to “hygroscopicity,” depending on the complexity of your essay’s subject.

The pollution essay thesis statement is a guiding line throughout your writing process. Every sentence you write should relate to your central argument and help advance it forward.

From when you start outlining until you write your conclusion and even when revising your draft, you should always ask yourself whether your writing helps you uphold your thesis.

Use credible sources to support your writing. Book and journal titles, research papers, and even interviews with respected scientists are good examples of what you should include in a bibliography.

You may also use pollution essay quotations to demonstrate scientists’ opinions or statistical numbers. When you reference your facts, your readers trust your writing and accept it as credible and truthful, as well as show a good understanding of the subject.

Give your essay an appropriate heading. Your pollution essay titles should clue your readers in on your argument. Using a “talking” title, which explains your subject at a glance, is a useful way of making your essay stand out among others.

If your subject ties together different issues, then you should think about using subheadings to make your essay more readable.

For example, when writing about nonpoint source pollution, you may need to mention its effects on both ocean and forest environments.

Doing so in different sections of your essay may help you structure your thoughts and bring together your arguments for a well-written conclusion.

Read sample essays written by others to help you understand your subject and essay structure better. Doing so will help you be consistent with your chosen citation style and immerse yourself in your research.

However, do not commit an academic offense by plagiarizing from the work of others.

Need more tips? Want to read an essay example? Visit IvyPanda!

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• The World Oceans Pollution and Overfishing Human beings have taken a lot of time to realize the need for ocean conservation to the extent that the ocean has succumbed to ecological challenges that have affected their lives in a variety of […]
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• Water Pollution in a Community: Mitigation Plan Though for the fact that planet earth is abundant with water and almost two-thirds of the planet is made up of water still it is viewed that in future years, a shortage of water may […]
• Integrated Pollution Prevention and Control Environmental management is dynamic and it is concurrent to the existing management strategies and agenda of the company. Statutes and legislations pertaining to environmental compliance enforce the need to implement environmental management and monitoring of […]
• Plastic Pollution From a Sociological Standpoint Wagner, as well as Miranda and de Carvalho-Souza, are in favor of increased recycling efforts to prevent more plastic from escaping into the sea.
• New York City Air Pollution Problem One positive impact of technological advancements on the environment in New York is the ability to provide communication options that are friendly to the environment.
• Kuwait’s Desert Pollution Obviously, the given problem might seem not that important if to observe the general environmental situation of the country, which is extremely close to that of the environmental catastrophe, but as an ordinary citizen, who […]
• Air Pollution Sources, Effects and Ways of Minimizing This paper discusses the various sources of air pollution, the effects of air pollution, and ways of minimizing air pollution. Definitely, the destruction of the atmosphere is a serious issue of concern to many people, […]
• Cashion Water Quality: Spatial Distribution of Water Pollution Incidents This essay discusses the quality of water as per the report of 2021 obtained from the municipality, the quality issue and the source of pollution, and how the pollution impacts human health and the environment […]
• Environmental Factors and Health Promotion: Indoor and Outdoor Air Pollution This presentation offers some information about the damage of air pollution and presents a health promotion plan with helpful resources and evidence from research.
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• Smog, Its Harm and Pollution Reduction Progress Smog can be defined as the mixture of solid and liquid fog and smoke particles that are formed under the impact of high humidity and calm air.
• Smog and Air Pollution in Los Angeles The city is often covered with a yellow veil in the sky, so the problem of smog is an actual problem of the state.
• Graveyard Ship Pollution in Kuwait The main legal issue of this case is the collision of two ships that led to the killing of millions of people and the dumping of waste along the sea.
• Environmental Pollution and Human Health The effects of sprawl on health workers are discussed in the article by Pohanka. It is similarly essential to take social justice and fairness into account because the effects of sprawl on population health are […]
• The Ecogeographical Impact of Air Pollution The weakness of the text is that the safety of NPs and their probable toxic effects on human health and the environment are not evaluated.
• Water Pollution as a Crime Against the Environment In particular, water pollution is a widespread crime against the environment, even though it is a severe felony that can result in harm to many people and vast territories.
• Carbon Offsets: Combatting Environmental Pollution I think that using other organizations or projects to offset an entity’s carbon footprint avoids the main goal of any present environmental protection efforts sustainability.
• Environmental Pollution: Waste Landfilling and Open Dumping The solution is simple and practical it is necessary to put efforts into further development of hard industries and stop financing the research of the issue that is useless.
• Air Pollution and Impact of Transportation Emissions of greenhouse gases, air pollution, the release of ballast water, aquatic invasive species, and oil and chemical leaks are only some of the environmental problems that marine transportation continues to cause.
• Pollution and Respiratory Disease in Louisiana The United States of America is an industrial powerhouse, a powerful nation that devoted much of its time to the growth and development of the petrochemical industry.
• Beat Plastic Pollution Essay These tips will help people to reduce the circulation of plastic in their lives. In conclusion, the best method to protect the environment is to minimize the accumulation of plastic waste by recycling, composting, and […]
• Air Pollution and Lung Disease To design a study in order to explore the link between lung disease and air pollution, it would be possible to follow a four-step process started by identifying the level or unit of analysis.
• American Society on Health and Pollution’s Activity The organization is purposed to inspire newly elected leaders to act as examples and lead the way in the promotion of a green economy that is sustainable for all American citizens.
• Environmental Justice: Pollution However, the issue of environmental racism transcends national boundaries and is likely to be repeated in other regions of the world.
• Air Pollution in China: Atmospheric Chemistry and Physics One of the most acute environmental problems in China is air pollution, which the authorities are trying to solve, but still, many people, factories, and active processes of globalization do not allow environmental programs to […]
• CSR Initiatives in Reducing Pollution and Carbon Emissions in GCC The purpose of this paper is to conduct a literature review evaluating the impact of CSR initiatives in reducing pollution and carbon emissions in GCC and the Middle East.
• Algae Explosion and Nitrogen Pollution in Lakes One of the most problematic aspects of nitrogen pollution as a form of nutrient pollution in lakes is the algae explosion.
• A Pollution Concern in the Anacostia River In addition, the unending sedimentation affected the river’s ecosystem due to the lack of sunshine, especially at the bottom of the river.
• Air Pollution and Child Health Conducting research, leading scholars, and summarizing the results of their efforts allowed the organization to investigate the numerous ways air pollution damages the human body.
• Environmental Protection: Pollution and Fossil Fuels The term used to describe a combination of oil and petroleum-related businesses, fossil fuel has been continuously cited as being dangerous for the planet.
• Importance of Mercury Water Pollution Problem Solutions The severity of the mercury contamination consequences depends on the age of the person exposed to the contamination, the way of contamination, the health condition, and many other factors.
• Issue of Pollution of Everest A policy that can be put in place by Nepal to address the current state of pollution on Everest is limiting the number of climbers to the mountain. The increase in the number of people […]
• The Impact of Atmospheric Pollution on Human Health and the Environment Atmospheric pollution is a set of environmental problems associated with releasing chemicals and accumulating concentrations of natural gases in the air.
• Air Pollution and Vulnerability to Covid-19 In other words, the findings will be used as one of the key arguments for showing that air pollution is detrimental to both individual and societal health.
• Poor Waste Disposal and Pollution in California For instance, the rapid increase in the number of factories and industries in California has led to more waste products in the state.
• Technical Report Pollution in Cities of Trinidad Many people who live in the environment close to the dumping sites are exposed to the daily combustion of the refuse, coupled with the inhalation of the emissions from the combusted material.
• Cultural Pollution in the Middle East The importance of the cultural patriarchal society suffers the whims of the feminist movement that has underscored the cultural values and roles of women.
• Fundamentals of Air Pollution The components of secondary air pollution include ozone and nitrogen oxides. Smog occurs when “car exhausts are exposed to direct sunlight”.
• The Reduction of Agricultural Nutrient Pollution: Possible Solutions The nutrients that are contained in fertilizer or manure may reach water basins and cause a dramatic increase in the populations of phytoplankton and algae.
• The Perspectives of Pollution for International Business Turning to the society’s role in changing the unsustainable system, the most important part of the discussion is usually dedicated to the role-changing possibility in the governmental structure.
• Pollution Problem: Sewage Spills in San Jose Water is a crucial element for all known forms of life to be able to live. Groundwater quality is essential for human consumption and social and economic activities.
• Equipment to Monitor Pollution Emissions In assessing the situation, the vital aspects are: the quality of the decision, the commitment of the subordinates, the knowledge of the leader, the structure of the problem, the probability of subordinates’ commitment, sharing the […]
• Global Plastic Pollution Problem and Its Drivers The primary challenge is the production and use of plastic products, which overwhelm the environment’s capacity to withstand. It cannot be burned because of air contamination, and the process of recycling equally results in plastic […]
• Plastic Pollution and Its Consequences Water in vapor form is also a product of combusted carbon-rich molecules and forms part of the hydrosphere from where it is absorbed into the biosphere.
• Newark Water Crisis: Water Pollution Problem The main problem was rooted in the fact that lead levels in the drinking water were highly elevated, which is dangerous and detrimental to the population’s health.
• Pollution Caused by Plastic Materials However, it is important to note that regardless of the many pleasant and appealing uses of plastics, the numerous health problems and dangers presented to the environment are gruesome.
• Pollution and Illegal Dumping in Chilliwack River Chilliwack River Watershed maintenance is under great pressure because of differing use of resources and activity, high demands for growth and recreation, and impacts to quality of water and riparian habitation from different water-use and […]
• Simply Green Products Firm: Pollution Allegations The natural decomposition is the surety that the company to the environmentalist organizations and the citizens. There is considerable proof that the company has been the primary producer of the packaging materials for the orchards […]
• Atmospheric Pollution Constituents A department dealing with the effects of atmospheric pollutants in the vicinity of an industrial complex has established a data table of measurements of a purity index Y on a scale of 0 to 1000 […]
• Air Pollution: The Problem’ Review Indoor pollution and related conditions are a big burden to the already suffering world according to the reports of the world health organization that it’s the 8th most important risk factor and is perceived to […]
• Law, Property Rights, and Air Pollution In the law of torts, ‘harm’ is considered when there is physical invasion to a person there fore in the case there was no violation of this law as the secretary was not harmed by […]
• Reducing Traffic Noise Pollution in Cairo In conclusion, it seems reasonable to state that the issue of traffic noise pollution is rapidly growing in Egypt’s capital Cairo and increasingly impacts public health.
• Air Pollution in Middle East: Saudi Arabia The rate of air pollution in the world has increased gradually since the advent of the industrial revolution in the early 1800s.
• Global Pollution and Climate Change Both of these works address the topic of Global pollution, Global warming, and Climate change, which are relevant to the current situation in the world.
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• Point vs. Non-Point Air Pollution To determine the air pollution source of a large smoke stack, one has to assess the physical characteristics of the smoke; description of the color concentration intensity is it grey or extremely dark?
• Noise Pollution: Best Practicable Means Magistrates’ Court identified Statutory Nuisance in the case and forwarded an abatement order against respondents along with a huge fine for their misconduct that led to noise pollution.
• Public Policy Issue: Particle Pollution in Chicago Metropolitan Area The Chicago metropolitan area has been mentioned quite a number of times in American Lung Association’s State of the Air 2008, an annual report that grades the quality of the air across the different cities […]
• Noise Pollution: Environmental Issue in Lagos, Nigeria The aim of the study would be to understand and evaluate the amount of noise pollution in Lagos, Nigeria and its affects on public health.
• Air Pollution and Health Issues in the US The industry of health care is closely connected to the industrial activities sector, which has the largest impact on the atmosphere through polluting the air, soil, and waters.
• Thames Water Company’s Pollution Issue and Ecocentrism Fines can be treated as a strong solution to this issue even though it is not presupposed by the ethical theory discussed, as they ensure that some funds can be spent on protecting the environment.
• Air Pollution Externalities and Possible Solutions In order to fully integrate public utility, power generation, policy and use of nuclear power in light of the growing concerns on the depletion of natural forms of energy as well as degradation of the […]
• Industrial Pollution in China and USA The pollution of world’s environment with industrial wastes is highly intensified and according to the authors’ opinion the scientific approach is the most significant and useful tool for the purpose of quick resolving of this […]
• Air Pollution and Ecological Perspectives of the Atmosphere The major contributors to CO2, one of the main pollutants in the atmosphere, are the burning of fossil fuels and deforestation.
• Pollution Is a Consistent Demolition of the Earth Pollution means the introduction into the environment of substances or energy that is liable to cause hazards to human health, harm to living resources and ecological systems, damage to structure or interfere with the legitimate […]
• Air Pollution and Its World History From the times of industrial revolution, smoke pollution was a concern and continues to be one with vehicles and industries replacing coal and wood.
• The Influence of Global Warming and Pollution on the Environment This essay is going to address global warming from a psychological point of view with an emphasis on the psychological and social reasons that make it important to tackle this problem which is threatening the […]
• Atmospheric Chemistry – Pollution Ozone, a photochemical pollutant, is formed by the oxidation of explosive organic compounds in the presence of sunlight and oxides of nitrogen in the atmosphere.
• Construction Technology and Air Pollution Hot-list section has new and transferable technology and highlights the features that appeal to construction companies, specifies and designers, owners of the building and end users.
• As China Roars, Pollution Reaches Deadly Extremes The idea is to harness the excess waters of the Yangtze River to replenish the Yellow River which perennially suffers from lack of water and the formation of silt.
• Noise and Sound Pollution The noise pollution should be considered by the duration of the sound, the frequency of noise, and whether there is any control to the sound or not.
• Pollution Control Policy: Glodal Issues Global warming poses a great problem for the global biosphere since it affects the habitat of most of the natural occupants of the global hemisphere.
• Earth’s Atmosphere and Natural Pollution The stratosphere is the next layer of the atmosphere and is from that 7 17 km range to about 30 km above the earth’s surface.
• Water Pollution: OIL Spills Aspects The effects of the oil spill on a species of ducks called the Harlequin ducks were formulated and the author attempted to trace out the immediate and residual effects of the oil on the birds.
• Atmospheric Pollution and Global Warming Green forests help in soaking the suspended particles in the air and thus clean the air for all of us to breathe.
• Recurrent Pollution of the Tisza River of Hungary The Tisza basin is located almost precisely in the geographical center of Europe and crosses the near-future boundary of the European Union.
• Marine Pollution: Management and International Legislation Marine environment refers to: the physical, chemical, geological and biological components, conditions and factors which interact and determine the productivity of, state, condition and quality of the marine ecosystem, the waters of the seas and […]
• Marine Pollution: Sources, Types, Pathways, and Status By examining sources, types, pathways, and status of water contamination in the context of the World Ocean, it is clear that most marine pollution caused by human actions, especially the mismanagement of plastic debris.
• The Public Perceptions of Air Pollution and Related Policies in London The primary questions for consideration are the public perceptions of air pollution and related policies in London and other cities of the United Kingdom, previous surveys regarding existing policies related to the environment or air […]
• Concerns of Ocean Ecosystem Pollution The range of adverse outcomes for ocean ecosystems can be discussed in volumes; however, the current discussion will focus on trash in the ocean waters, acidification, and the disruption of the marine life cycles.
• Food Distribution and Water Pollution Therefore, food distribution is one of the central reasons for water pollution. According to Greenpeace, one of the ways to improve the ecology of the planet is by creating healthy food markets.
• How China Cuts Its Air Pollution 5, which is the smallest and one of the most harmful polluting particles, were 54 percent lower in the last quarter of 2017 as compared to the same period in 2016, specifically in Beijing.
• Haze Pollution in China One of the outstanding aspects of pollution in the country is that the Chinese are highly desensitized and aware of issues surrounding this matter.
• Pollution and Federal Environmental Policy Pollution continues to influence the flora and the fauna of the United States, as well as people in urban and even rural areas.
• Plastic Pollution and Social Institutions The purpose of this paper is to investigate the political and economic barriers that hamper the efforts to reduce plastic pollution and discuss the ways in how they could be overcome.
• Social Activism Against Plastic Pollution Of the 30 million tons of plastic waste in the United States in 2009, only 7% were sent for recycling, which primarily damages marine life.
• Climate Change: Reducing Industrial Air Pollution One of the most effective measures of air quality in the USA is the Air Quality Index, which estimates air conditions by concentrations of such pollutants as particle solution, nitrogen and sulfur dioxide, carbon monoxide, […]
• Pollution as a Social Issue and Mass Media’s Role The reason why plastic pollution gained traction only during the 21st century is directly connected to the invention of the Internet and the technological advances in electronics.
• Environmental Ethics. Optimal Pollution: Reality or Myth? The effects of globalization and environmental change have caused the resurgence of environmentalism, yet the necessity to sustain industries and the global economy invalidates the idea of a pollution-free environment.
• Environmental Pollution and Contamination The rains are known to corrode marble and metals, cause respiratory diseases in human beings and increase the acidity of the soil.
• Low Pollution Car Engine The following is a discussion on the introduction of the low pollution car engine and its benefits to the UAE. In addition, pollution and climate change will be a thing of the past.
• Chemistry: Environmental Pollution in Hungary The acidification of water bodies leads to the death of numerous species that are susceptible to the presence of acid. Part of the problem is caused by the fact that Hungary is currently forced to […]
• Environmental Pollution Analysis The author explains that the damaging alterations have become possible due to the use of a large number of pesticides in the area.
• Coal Pollution in China as an Environmental Problem Thesis: Coal pollution in China has been a significant cause of environmental pollution-China being one of the largest coal producers in the world- therefore, necessitating the development of appropriate measures to reduce its severity.
• Air Pollution, Its Constituents and Health Effects The National Ambient Air Quality Standards are the regulations or policies that are adopted by states to ensure the safety of the environment.
• The Deepwater Horizon Oil Platform Pollution The oil spillage in the sea can result to the death of sea animals as well as plants that thrive in the water because of the dangerous chemicals that are contained in the oil.
• Air Pollution in the United Arab Emirates’ Cities In the article called Evaluating the Potential Impact of Global Warming on the UAE Residential Buildings, the author focuses on the negative consequences of global warming on the situation in the United Arab Emirates.
• Advanced Pollution Prevention in the United States In the United States, the overview of the previous legislation shows that the government used to enforce measures that would deal with pollution control which occurred at the final stage of production processes. The Pollution […]
• Environmental Pollution and Increased Birds Death The increase in the population of different animals may also cause the death of birds. This leads to the extinction of some animals and birds hence massive death.
• Climate Change, Air Pollution, Soil Degradation Then followed by outdoor air pollution, soil degradation which can also be called as soil contamination, global overpopulation, drinking water pollution, nuclear waste build-up, disappearing of the water supplies, indoor air pollution, depletion of the […]
• China Shenhua Energy Company: Pollution Reducing Although the Chinese government recognized the issue of pollution and announced a course for liberalization of the economy and a greater emphasis on ecology during the 12th 5-year plan, the transformation from a coal-based energy […]
• Air Pollution in Washington State and Healthy Living of People The problem of air pollution is closely related to the issue of the energy supply of the US. Due to the high level of air pollution in Washington state, there is a growing threat to […]
• Air Pollution as a Factor for Renal Cancer Therefore, to prevent renal cancer, it is crucial to examine the primary causes and look for better strategies to curb the issue.
• Podocnemis Lewyana: Habitat Loss, Overfishing and Pollution The second factor is overhunting, which in the case of Magdalena River Turtle leads to the inability of these animals to locate food.
• Pollution in the San Francisco Bay The rivers provide fresh water for domestic use to many civilians, and it is apparent that the authorities have given the power plant the freedom to test the quantity of chemicals in the waste water.
• Indoor Air Pollution: The Silent Killer in Rural India The video “Indoor air pollution: The silent killer” discusses the detrimental impact of indoor air pollution in rural Indian households on people’s health. The problem of indoor air pollution is rather significant, and people should […]
• Water Pollution and Associated Health Risks The results of plenty of studies indicate the existence of the relation between the contamination of water by hazardous chemicals and the development of respiratory and cardiovascular diseases, cancer, asthma, allergies, as well as reproductive […]
• Air Pollution and China’s Governmental Measures The consequences of air pollution in China are already becoming evident, and not only they are the reason for environmental problems, but also they have a significant influence on the health of Chinese people living […]
• Lake Erie Water Pollution There are worries among the members of the community that the lake could be facing another episode of high toxicity, and they have called for the authorities to investigate the main causes of the pollution […]
• Environmental Pollution and Green Policies Although various scholars are of the view that green technology reduces the level of pollution, adequate research on the use of this form of technology needs to be conducted so as to fully contain environmental […]
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• Water & Air Pollution and Health Issues in Brazil The main environmental effects of pollution include the destruction of marine habitats, water scarcity, and anoxia. The conclusion is informative because the writer includes strategies to alleviate the problem of air and water pollution in […]
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• Air Pollution Impact on Children’s Health in the US In these parts of the country, the level of air pollution is much higher. Nevertheless, the growing number of vehicles in the United States contributes to air pollution.
• Traffic-Related Air Pollution and Health Effects It emphasizes the fact that air contamination has a negative influence on the health of the representatives of the general public.
• Nebraska Pollution Prevention Project The article is about Nebraska’s Partners in Pollution Prevention program and the benefits it has brought to the state in the reduction of pollution caused by small businesses.
• Storm Water Pollution Prevention Plan All players need to be trained in significant areas of business so as they can handle them with care and beware of the potential they have in causing damage.
• Water Pollution in the US: Causes and Control Although water pollution can hardly be ceased entirely, the current rates of water pollution can be reduced by resorting to the sustainable principle of water use in both the industrial area and the realm of […]
• Importance of Water in Economics: Uses, Pollution, and Sustainable Growth Some of the water is found in the continents’ rivers, lakes and in the subsurface. This research tries to explain the importance of water especially in an economist’s perspective by explaining the uses of water […]
• Air Pollution in Los Angeles The escalation of congestion in the city has worsened the problem of air pollution because of the volume of unhealthy air emitted in the atmosphere.
• Noise Pollution: Urban Traffic Noise Besides these two, noise also has an effect on the learning of an individual so that it distracts the individual in a way that s/he is not able to learn, as would be the case […]
• Environmental Revolution: Air Pollution in China
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• Pollution of the Ganges and Its Main Factors
• Pollution Externalities Role in Management Economics
• Marine Pollution and the Anthropogenic Effects Upon It
• The New York City Air Pollution
• Air Pollution Effects on the Health and Environment
• Dealing With Air Pollution
• Environmental Justice and Air Pollution in Canada
• Environment Destruction: Pollution
• Big Coal and the Natural Environment Pollution
• Principles of Air Pollution Control and Analysis
• China’s Air Pollution Problem
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• Business and Pollution Inequality in Poor States
• China’s Air Pollution Is Not Unique
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• Air and Water Pollution
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• Fossil Fuels Subsidies and the Impact of Pollution on Health and Lifetime Earnings
• Causes of Water Pollution and the Present Environmental Solution
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• The Problem of Ocean Pollution in Modern World
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• The Effects of Noise Pollution
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• Air and Water Pollution in Los Angeles
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• Water Pollution Causes and Climate Impacts
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• Mud Lick Creek Project – Fresh Water Pollution
• A Discussion of Air Pollution & Related Health Implications on the Community
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• Why Air Pollution Can Harm the Environment Dramatically?
• What Are the Sources of Air Pollution?
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• What Causes Water Pollution and Its Effects?
• What Can the Public Do to Curb Pollution?
• Will COVID-19 Containment and Treatment Measures Drive Shifts in Marine Litter Pollution?
• Does Inequality Matter Air Pollution and Health Relationship?
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• What Will the Effects Be if We Don’t Stop Plastic Pollution in Our Oceans?
• Does Air Pollution Crowd Out Foreign Direct Investment Inflows?
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• Does Trade Promote Environmental Coordination of Pollution in International Rivers?
• Who Suffers From Indoor Air Pollution?
• What Are the Main Ways to Reduce Pollution?
• What Causes Haze Pollution?
• Environment Research Topics
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Air Pollution

Our overview of indoor and outdoor air pollution.

By: Hannah Ritchie and Max Roser

This article was first published in October 2017 and last revised in February 2024.

Air pollution is one of the world's largest health and environmental problems. It develops in two contexts: indoor (household) air pollution and outdoor air pollution.

In this topic page, we look at the aggregate picture of air pollution – both indoor and outdoor. We also have dedicated topic pages that look in more depth at these subjects:

Indoor Air Pollution

Look in detail at the data and research on the health impacts of Indoor Air Pollution, attributed deaths, and its causes across the world

Outdoor Air Pollution

Look in detail at the data and research on exposure to Outdoor Air Pollution, its health impacts, and attributed deaths across the world

Look in detail at the data and research on energy consumption, its impacts around the world today, and how this has changed over time

See all interactive charts on Air Pollution ↓

Other research and writing on air pollution on Our World in Data:

• Air pollution: does it get worse before it gets better?
• Data Review: How many people die from air pollution?
• Energy poverty and indoor air pollution: a problem as old as humanity that we can end within our lifetime
• How many people do not have access to clean fuels for cooking?
• What are the safest and cleanest sources of energy?
• What the history of London’s air pollution can tell us about the future of today’s growing megacities
• When will countries phase out coal power?

Air pollution is one of the world's leading risk factors for death

Air pollution is responsible for millions of deaths each year.

Air pollution – the combination of outdoor and indoor particulate matter and ozone – is a risk factor for many of the leading causes of death, including heart disease, stroke, lower respiratory infections, lung cancer, diabetes, and chronic obstructive pulmonary disease (COPD).

The Institute for Health Metrics and Evaluation (IHME), in its Global Burden of Disease study, provides estimates of the number of deaths attributed to the range of risk factors for disease. 1

In the visualization, we see the number of deaths per year attributed to each risk factor. This chart shows the global total but can be explored for any country or region using the "change country" toggle.

Air pollution is one of the leading risk factors for death. In low-income countries, it is often very near the top of the list (or is the leading risk factor).

Air pollution contributes to one in ten deaths globally

In recent years, air pollution has contributed to one in ten deaths globally. 2

In the map shown here, we see the share of deaths attributed to air pollution across the world.

Air pollution is one of the leading risk factors for disease burden

Air pollution is one of the leading risk factors for death. But its impacts go even further; it is also one of the main contributors to the global disease burden.

Global disease burden takes into account not only years of life lost to early death but also the number of years lived in poor health.

In the visualization, we see risk factors ranked in order of DALYs – disability-adjusted life years – the metric used to assess disease burden. Again, air pollution is near the top of the list, making it one of the leading risk factors for poor health across the world.

Air pollution not only takes years from people's lives but also has a large effect on the quality of life while they're still living.

Who is most affected by air pollution?

Death rates from air pollution are highest in low-to-middle-income countries.

Air pollution is a health and environmental issue across all countries of the world but with large differences in severity.

In the interactive map, we show death rates from air pollution across the world, measured as the number of deaths per 100,000 people in a given country or region.

The burden of air pollution tends to be greater across both low and middle-income countries for two reasons: indoor pollution rates tend to be high in low-income countries due to a reliance on solid fuels for cooking, and outdoor air pollution tends to increase as countries industrialize and shift from low to middle incomes.

A map of the number of deaths from air pollution by country can be found here .

How are death rates from air pollution changing?

Death rates from air pollution are falling – mainly due to improvements in indoor pollution.

In the visualization, we show global death rates from air pollution over time – shown as the total air pollution – in addition to the individual contributions from outdoor and indoor pollution.

Globally, we see that in recent decades, the death rates from total air pollution have declined: since 1990, death rates have nearly halved. But, as we see from the breakdown, this decline has been primarily driven by improvements in indoor air pollution.

Death rates from indoor air pollution have seen an impressive decline, while improvements in outdoor pollution have been much more modest.

You can explore this data for any country or region using the "change country" toggle on the interactive chart.

Interactive charts on air pollution

Murray, C. J., Aravkin, A. Y., Zheng, P., Abbafati, C., Abbas, K. M., Abbasi-Kangevari, M., ... & Borzouei, S. (2020). Global burden of 87 risk factors in 204 countries and territories, 1990–2019: a systematic analysis for the Global Burden of Disease Study 2019 .  The Lancet ,  396 (10258), 1223-1249.

Here, we use the term 'contributes,' meaning it was one of the attributed risk factors for a given disease or cause of death. There can be multiple risk factors for a given disease that can amplify one another. This means that in some cases, air pollution was not the only risk factor but one of several.

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All visualizations, data, and code produced by Our World in Data are completely open access under the Creative Commons BY license . You have the permission to use, distribute, and reproduce these in any medium, provided the source and authors are credited.

The data produced by third parties and made available by Our World in Data is subject to the license terms from the original third-party authors. We will always indicate the original source of the data in our documentation, so you should always check the license of any such third-party data before use and redistribution.

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Air Pollution: Everything You Need to Know

How smog, soot, greenhouse gases, and other top air pollutants are affecting the planet—and your health.

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What is air pollution?

What causes air pollution, effects of air pollution, air pollution in the united states, air pollution and environmental justice, controlling air pollution, how to help reduce air pollution, how to protect your health.

Air pollution  refers to the release of pollutants into the air—pollutants that are detrimental to human health and the planet as a whole. According to the  World Health Organization (WHO) , each year, indoor and outdoor air pollution is responsible for nearly seven million deaths around the globe. Ninety-nine percent of human beings currently breathe air that exceeds the WHO’s guideline limits for pollutants, with those living in low- and middle-income countries suffering the most. In the United States, the  Clean Air Act , established in 1970, authorizes the U.S. Environmental Protection Agency (EPA) to safeguard public health by regulating the emissions of these harmful air pollutants.

“Most air pollution comes from energy use and production,” says  John Walke , director of the Clean Air team at NRDC. Driving a car on gasoline, heating a home with oil, running a power plant on  fracked gas : In each case, a fossil fuel is burned and harmful chemicals and gases are released into the air.

“We’ve made progress over the last 50 years in improving air quality in the United States, thanks to the Clean Air Act. But climate change will make it harder in the future to meet pollution standards, which are designed to  protect health ,” says Walke.

Air pollution is now the world’s fourth-largest risk factor for early death. According to the 2020  State of Global Air  report —which summarizes the latest scientific understanding of air pollution around the world—4.5 million deaths were linked to outdoor air pollution exposures in 2019, and another 2.2 million deaths were caused by indoor air pollution. The world’s most populous countries, China and India, continue to bear the highest burdens of disease.

“Despite improvements in reducing global average mortality rates from air pollution, this report also serves as a sobering reminder that the climate crisis threatens to worsen air pollution problems significantly,” explains  Vijay Limaye , senior scientist in NRDC’s Science Office. Smog, for instance, is intensified by increased heat, forming when the weather is warmer and there’s more ultraviolet radiation. In addition, climate change increases the production of allergenic air pollutants, including mold (thanks to damp conditions caused by extreme weather and increased flooding) and pollen (due to a longer pollen season). “Climate change–fueled droughts and dry conditions are also setting the stage for dangerous wildfires,” adds Limaye. “ Wildfire smoke can linger for days and pollute the air with particulate matter hundreds of miles downwind.”

The effects of air pollution on the human body vary, depending on the type of pollutant, the length and level of exposure, and other factors, including a person’s individual health risks and the cumulative impacts of multiple pollutants or stressors.

Smog and soot

These are the two most prevalent types of air pollution. Smog (sometimes referred to as ground-level ozone) occurs when emissions from combusting fossil fuels react with sunlight. Soot—a type of  particulate matter —is made up of tiny particles of chemicals, soil, smoke, dust, or allergens that are carried in the air. The sources of smog and soot are similar. “Both come from cars and trucks, factories, power plants, incinerators, engines, generally anything that combusts fossil fuels such as coal, gasoline, or natural gas,” Walke says.

Smog can irritate the eyes and throat and also damage the lungs, especially those of children, senior citizens, and people who work or exercise outdoors. It’s even worse for people who have asthma or allergies; these extra pollutants can intensify their symptoms and trigger asthma attacks. The tiniest airborne particles in soot are especially dangerous because they can penetrate the lungs and bloodstream and worsen bronchitis, lead to heart attacks, and even hasten death. In  2020, a report from Harvard’s T.H. Chan School of Public Health showed that COVID-19 mortality rates were higher in areas with more particulate matter pollution than in areas with even slightly less, showing a correlation between the virus’s deadliness and long-term exposure to air pollution. 

These findings also illuminate an important  environmental justice issue . Because highways and polluting facilities have historically been sited in or next to low-income neighborhoods and communities of color, the negative effects of this pollution have been  disproportionately experienced by the people who live in these communities.

Hazardous air pollutants

A number of air pollutants pose severe health risks and can sometimes be fatal, even in small amounts. Almost 200 of them are regulated by law; some of the most common are mercury,  lead , dioxins, and benzene. “These are also most often emitted during gas or coal combustion, incineration, or—in the case of benzene—found in gasoline,” Walke says. Benzene, classified as a carcinogen by the EPA, can cause eye, skin, and lung irritation in the short term and blood disorders in the long term. Dioxins, more typically found in food but also present in small amounts in the air, is another carcinogen that can affect the liver in the short term and harm the immune, nervous, and endocrine systems, as well as reproductive functions.  Mercury  attacks the central nervous system. In large amounts, lead can damage children’s brains and kidneys, and even minimal exposure can affect children’s IQ and ability to learn.

Another category of toxic compounds, polycyclic aromatic hydrocarbons (PAHs), are by-products of traffic exhaust and wildfire smoke. In large amounts, they have been linked to eye and lung irritation, blood and liver issues, and even cancer.  In one study , the children of mothers exposed to PAHs during pregnancy showed slower brain-processing speeds and more pronounced symptoms of ADHD.

Greenhouse gases

While these climate pollutants don’t have the direct or immediate impacts on the human body associated with other air pollutants, like smog or hazardous chemicals, they are still harmful to our health. By trapping the earth’s heat in the atmosphere, greenhouse gases lead to warmer temperatures, which in turn lead to the hallmarks of climate change: rising sea levels, more extreme weather, heat-related deaths, and the increased transmission of infectious diseases. In 2021, carbon dioxide accounted for roughly 79 percent of the country’s total greenhouse gas emissions, and methane made up more than 11 percent. “Carbon dioxide comes from combusting fossil fuels, and methane comes from natural and industrial sources, including large amounts that are released during oil and gas drilling,” Walke says. “We emit far larger amounts of carbon dioxide, but methane is significantly more potent, so it’s also very destructive.” 

Another class of greenhouse gases,  hydrofluorocarbons (HFCs) , are thousands of times more powerful than carbon dioxide in their ability to trap heat. In October 2016, more than 140 countries signed the Kigali Agreement to reduce the use of these chemicals—which are found in air conditioners and refrigerators—and develop greener alternatives over time. (The United States officially signed onto the  Kigali Agreement in 2022.)

Pollen and mold

Mold and allergens from trees, weeds, and grass are also carried in the air, are exacerbated by climate change, and can be hazardous to health. Though they aren’t regulated, they can be considered a form of air pollution. “When homes, schools, or businesses get water damage, mold can grow and produce allergenic airborne pollutants,” says Kim Knowlton, professor of environmental health sciences at Columbia University and a former NRDC scientist. “ Mold exposure can precipitate asthma attacks  or an allergic response, and some molds can even produce toxins that would be dangerous for anyone to inhale.”

Pollen allergies are worsening  because of climate change . “Lab and field studies are showing that pollen-producing plants—especially ragweed—grow larger and produce more pollen when you increase the amount of carbon dioxide that they grow in,” Knowlton says. “Climate change also extends the pollen production season, and some studies are beginning to suggest that ragweed pollen itself might be becoming a more potent allergen.” If so, more people will suffer runny noses, fevers, itchy eyes, and other symptoms. “And for people with allergies and asthma, pollen peaks can precipitate asthma attacks, which are far more serious and can be life-threatening.”

More than one in three U.S. residents—120 million people—live in counties with unhealthy levels of air pollution, according to the  2023  State of the Air  report by the American Lung Association (ALA). Since the annual report was first published, in 2000, its findings have shown how the Clean Air Act has been able to reduce harmful emissions from transportation, power plants, and manufacturing.

Recent findings, however, reflect how climate change–fueled wildfires and extreme heat are adding to the challenges of protecting public health. The latest report—which focuses on ozone, year-round particle pollution, and short-term particle pollution—also finds that people of color are 61 percent more likely than white people to live in a county with a failing grade in at least one of those categories, and three times more likely to live in a county that fails in all three.

In rankings for each of the three pollution categories covered by the ALA report, California cities occupy the top three slots (i.e., were highest in pollution), despite progress that the Golden State has made in reducing air pollution emissions in the past half century. At the other end of the spectrum, these cities consistently rank among the country’s best for air quality: Burlington, Vermont; Honolulu; and Wilmington, North Carolina. 

No one wants to live next door to an incinerator, oil refinery, port, toxic waste dump, or other polluting site. Yet millions of people around the world do, and this puts them at a much higher risk for respiratory disease, cardiovascular disease, neurological damage, cancer, and death. In the United States, people of color are 1.5 times more likely than whites to live in areas with poor air quality, according to the ALA.

Historically, racist zoning policies and discriminatory lending practices known as  redlining  have combined to keep polluting industries and car-choked highways away from white neighborhoods and have turned communities of color—especially low-income and working-class communities of color—into sacrifice zones, where residents are forced to breathe dirty air and suffer the many health problems associated with it. In addition to the increased health risks that come from living in such places, the polluted air can economically harm residents in the form of missed workdays and higher medical costs.

Environmental racism isn't limited to cities and industrial areas. Outdoor laborers, including the estimated three million migrant and seasonal farmworkers in the United States, are among the most vulnerable to air pollution—and they’re also among the least equipped, politically, to pressure employers and lawmakers to affirm their right to breathe clean air.

Recently,  cumulative impact mapping , which uses data on environmental conditions and demographics, has been able to show how some communities are overburdened with layers of issues, like high levels of poverty, unemployment, and pollution. Tools like the  Environmental Justice Screening Method  and the EPA’s  EJScreen  provide evidence of what many environmental justice communities have been explaining for decades: that we need land use and public health reforms to ensure that vulnerable areas are not overburdened and that the people who need resources the most are receiving them.

In the United States, the  Clean Air Act  has been a crucial tool for reducing air pollution since its passage in 1970, although fossil fuel interests aided by industry-friendly lawmakers have frequently attempted to  weaken its many protections. Ensuring that this bedrock environmental law remains intact and properly enforced will always be key to maintaining and improving our air quality.

But the best, most effective way to control air pollution is to speed up our transition to cleaner fuels and industrial processes. By switching over to renewable energy sources (such as wind and solar power), maximizing fuel efficiency in our vehicles, and replacing more and more of our gasoline-powered cars and trucks with electric versions, we'll be limiting air pollution at its source while also curbing the global warming that heightens so many of its worst health impacts.

And what about the economic costs of controlling air pollution? According to a report on the Clean Air Act commissioned by NRDC, the annual  benefits of cleaner air  are up to 32 times greater than the cost of clean air regulations. Those benefits include up to 370,000 avoided premature deaths, 189,000 fewer hospital admissions for cardiac and respiratory illnesses, and net economic benefits of up to $3.8 trillion for the U.S. economy every year.

“The less gasoline we burn, the better we’re doing to reduce air pollution and the harmful effects of climate change,” Walke explains. “Make good choices about transportation. When you can, ride a bike, walk, or take public transportation. For driving, choose a car that gets better miles per gallon of gas or  buy an electric car .” You can also investigate your power provider options—you may be able to request that your electricity be supplied by wind or solar. Buying your food locally cuts down on the fossil fuels burned in trucking or flying food in from across the world. And most important: “Support leaders who push for clean air and water and responsible steps on climate change,” Walke says.

• “When you see in the news or hear on the weather report that pollution levels are high, it may be useful to limit the time when children go outside or you go for a jog,” Walke says. Generally, ozone levels tend to be lower in the morning.
• If you exercise outside, stay as far as you can from heavily trafficked roads. Then shower and wash your clothes to remove fine particles.
• The air may look clear, but that doesn’t mean it’s pollution free. Utilize tools like the EPA’s air pollution monitor,  AirNow , to get the latest conditions. If the air quality is bad, stay inside with the windows closed.
• If you live or work in an area that’s prone to wildfires,  stay away from the harmful smoke  as much as you’re able. Consider keeping a small stock of masks to wear when conditions are poor. The most ideal masks for smoke particles will be labelled “NIOSH” (which stands for National Institute for Occupational Safety and Health) and have either “N95” or “P100” printed on it.
• If you’re using an air conditioner while outdoor pollution conditions are bad, use the recirculating setting to limit the amount of polluted air that gets inside. 

This story was originally published on November 1, 2016, and has been updated with new information and links.

This NRDC.org story is available for online republication by news media outlets or nonprofits under these conditions: The writer(s) must be credited with a byline; you must note prominently that the story was originally published by NRDC.org and link to the original; the story cannot be edited (beyond simple things such as grammar); you can’t resell the story in any form or grant republishing rights to other outlets; you can’t republish our material wholesale or automatically—you need to select stories individually; you can’t republish the photos or graphics on our site without specific permission; you should drop us a note to let us know when you’ve used one of our stories.

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Environmental and Health Impacts of Air Pollution: A Review

Ioannis manisalidis.

1 Delphis S.A., Kifisia, Greece

2 Laboratory of Hygiene and Environmental Protection, Faculty of Medicine, Democritus University of Thrace, Alexandroupolis, Greece

Elisavet Stavropoulou

3 Centre Hospitalier Universitaire Vaudois (CHUV), Service de Médicine Interne, Lausanne, Switzerland

Agathangelos Stavropoulos

4 School of Social and Political Sciences, University of Glasgow, Glasgow, United Kingdom

Eugenia Bezirtzoglou

One of our era's greatest scourges is air pollution, on account not only of its impact on climate change but also its impact on public and individual health due to increasing morbidity and mortality. There are many pollutants that are major factors in disease in humans. Among them, Particulate Matter (PM), particles of variable but very small diameter, penetrate the respiratory system via inhalation, causing respiratory and cardiovascular diseases, reproductive and central nervous system dysfunctions, and cancer. Despite the fact that ozone in the stratosphere plays a protective role against ultraviolet irradiation, it is harmful when in high concentration at ground level, also affecting the respiratory and cardiovascular system. Furthermore, nitrogen oxide, sulfur dioxide, Volatile Organic Compounds (VOCs), dioxins, and polycyclic aromatic hydrocarbons (PAHs) are all considered air pollutants that are harmful to humans. Carbon monoxide can even provoke direct poisoning when breathed in at high levels. Heavy metals such as lead, when absorbed into the human body, can lead to direct poisoning or chronic intoxication, depending on exposure. Diseases occurring from the aforementioned substances include principally respiratory problems such as Chronic Obstructive Pulmonary Disease (COPD), asthma, bronchiolitis, and also lung cancer, cardiovascular events, central nervous system dysfunctions, and cutaneous diseases. Last but not least, climate change resulting from environmental pollution affects the geographical distribution of many infectious diseases, as do natural disasters. The only way to tackle this problem is through public awareness coupled with a multidisciplinary approach by scientific experts; national and international organizations must address the emergence of this threat and propose sustainable solutions.

Approach to the Problem

The interactions between humans and their physical surroundings have been extensively studied, as multiple human activities influence the environment. The environment is a coupling of the biotic (living organisms and microorganisms) and the abiotic (hydrosphere, lithosphere, and atmosphere).

Pollution is defined as the introduction into the environment of substances harmful to humans and other living organisms. Pollutants are harmful solids, liquids, or gases produced in higher than usual concentrations that reduce the quality of our environment.

Human activities have an adverse effect on the environment by polluting the water we drink, the air we breathe, and the soil in which plants grow. Although the industrial revolution was a great success in terms of technology, society, and the provision of multiple services, it also introduced the production of huge quantities of pollutants emitted into the air that are harmful to human health. Without any doubt, the global environmental pollution is considered an international public health issue with multiple facets. Social, economic, and legislative concerns and lifestyle habits are related to this major problem. Clearly, urbanization and industrialization are reaching unprecedented and upsetting proportions worldwide in our era. Anthropogenic air pollution is one of the biggest public health hazards worldwide, given that it accounts for about 9 million deaths per year ( 1 ).

Without a doubt, all of the aforementioned are closely associated with climate change, and in the event of danger, the consequences can be severe for mankind ( 2 ). Climate changes and the effects of global planetary warming seriously affect multiple ecosystems, causing problems such as food safety issues, ice and iceberg melting, animal extinction, and damage to plants ( 3 , 4 ).

Air pollution has various health effects. The health of susceptible and sensitive individuals can be impacted even on low air pollution days. Short-term exposure to air pollutants is closely related to COPD (Chronic Obstructive Pulmonary Disease), cough, shortness of breath, wheezing, asthma, respiratory disease, and high rates of hospitalization (a measurement of morbidity).

The long-term effects associated with air pollution are chronic asthma, pulmonary insufficiency, cardiovascular diseases, and cardiovascular mortality. According to a Swedish cohort study, diabetes seems to be induced after long-term air pollution exposure ( 5 ). Moreover, air pollution seems to have various malign health effects in early human life, such as respiratory, cardiovascular, mental, and perinatal disorders ( 3 ), leading to infant mortality or chronic disease in adult age ( 6 ).

National reports have mentioned the increased risk of morbidity and mortality ( 1 ). These studies were conducted in many places around the world and show a correlation between daily ranges of particulate matter (PM) concentration and daily mortality. Climate shifts and global planetary warming ( 3 ) could aggravate the situation. Besides, increased hospitalization (an index of morbidity) has been registered among the elderly and susceptible individuals for specific reasons. Fine and ultrafine particulate matter seems to be associated with more serious illnesses ( 6 ), as it can invade the deepest parts of the airways and more easily reach the bloodstream.

Air pollution mainly affects those living in large urban areas, where road emissions contribute the most to the degradation of air quality. There is also a danger of industrial accidents, where the spread of a toxic fog can be fatal to the populations of the surrounding areas. The dispersion of pollutants is determined by many parameters, most notably atmospheric stability and wind ( 6 ).

In developing countries ( 7 ), the problem is more serious due to overpopulation and uncontrolled urbanization along with the development of industrialization. This leads to poor air quality, especially in countries with social disparities and a lack of information on sustainable management of the environment. The use of fuels such as wood fuel or solid fuel for domestic needs due to low incomes exposes people to bad-quality, polluted air at home. It is of note that three billion people around the world are using the above sources of energy for their daily heating and cooking needs ( 8 ). In developing countries, the women of the household seem to carry the highest risk for disease development due to their longer duration exposure to the indoor air pollution ( 8 , 9 ). Due to its fast industrial development and overpopulation, China is one of the Asian countries confronting serious air pollution problems ( 10 , 11 ). The lung cancer mortality observed in China is associated with fine particles ( 12 ). As stated already, long-term exposure is associated with deleterious effects on the cardiovascular system ( 3 , 5 ). However, it is interesting to note that cardiovascular diseases have mostly been observed in developed and high-income countries rather than in the developing low-income countries exposed highly to air pollution ( 13 ). Extreme air pollution is recorded in India, where the air quality reaches hazardous levels. New Delhi is one of the more polluted cities in India. Flights in and out of New Delhi International Airport are often canceled due to the reduced visibility associated with air pollution. Pollution is occurring both in urban and rural areas in India due to the fast industrialization, urbanization, and rise in use of motorcycle transportation. Nevertheless, biomass combustion associated with heating and cooking needs and practices is a major source of household air pollution in India and in Nepal ( 14 , 15 ). There is spatial heterogeneity in India, as areas with diverse climatological conditions and population and education levels generate different indoor air qualities, with higher PM 2.5 observed in North Indian states (557–601 μg/m 3 ) compared to the Southern States (183–214 μg/m 3 ) ( 16 , 17 ). The cold climate of the North Indian areas may be the main reason for this, as longer periods at home and more heating are necessary compared to in the tropical climate of Southern India. Household air pollution in India is associated with major health effects, especially in women and young children, who stay indoors for longer periods. Chronic obstructive respiratory disease (CORD) and lung cancer are mostly observed in women, while acute lower respiratory disease is seen in young children under 5 years of age ( 18 ).

Accumulation of air pollution, especially sulfur dioxide and smoke, reaching 1,500 mg/m3, resulted in an increase in the number of deaths (4,000 deaths) in December 1952 in London and in 1963 in New York City (400 deaths) ( 19 ). An association of pollution with mortality was reported on the basis of monitoring of outdoor pollution in six US metropolitan cities ( 20 ). In every case, it seems that mortality was closely related to the levels of fine, inhalable, and sulfate particles more than with the levels of total particulate pollution, aerosol acidity, sulfur dioxide, or nitrogen dioxide ( 20 ).

Furthermore, extremely high levels of pollution are reported in Mexico City and Rio de Janeiro, followed by Milan, Ankara, Melbourne, Tokyo, and Moscow ( 19 ).

Based on the magnitude of the public health impact, it is certain that different kinds of interventions should be taken into account. Success and effectiveness in controlling air pollution, specifically at the local level, have been reported. Adequate technological means are applied considering the source and the nature of the emission as well as its impact on health and the environment. The importance of point sources and non-point sources of air pollution control is reported by Schwela and Köth-Jahr ( 21 ). Without a doubt, a detailed emission inventory must record all sources in a given area. Beyond considering the above sources and their nature, topography and meteorology should also be considered, as stated previously. Assessment of the control policies and methods is often extrapolated from the local to the regional and then to the global scale. Air pollution may be dispersed and transported from one region to another area located far away. Air pollution management means the reduction to acceptable levels or possible elimination of air pollutants whose presence in the air affects our health or the environmental ecosystem. Private and governmental entities and authorities implement actions to ensure the air quality ( 22 ). Air quality standards and guidelines were adopted for the different pollutants by the WHO and EPA as a tool for the management of air quality ( 1 , 23 ). These standards have to be compared to the emissions inventory standards by causal analysis and dispersion modeling in order to reveal the problematic areas ( 24 ). Inventories are generally based on a combination of direct measurements and emissions modeling ( 24 ).

As an example, we state here the control measures at the source through the use of catalytic converters in cars. These are devices that turn the pollutants and toxic gases produced from combustion engines into less-toxic pollutants by catalysis through redox reactions ( 25 ). In Greece, the use of private cars was restricted by tracking their license plates in order to reduce traffic congestion during rush hour ( 25 ).

Concerning industrial emissions, collectors and closed systems can keep the air pollution to the minimal standards imposed by legislation ( 26 ).

Current strategies to improve air quality require an estimation of the economic value of the benefits gained from proposed programs. These proposed programs by public authorities, and directives are issued with guidelines to be respected.

In Europe, air quality limit values AQLVs (Air Quality Limit Values) are issued for setting off planning claims ( 27 ). In the USA, the NAAQS (National Ambient Air Quality Standards) establish the national air quality limit values ( 27 ). While both standards and directives are based on different mechanisms, significant success has been achieved in the reduction of overall emissions and associated health and environmental effects ( 27 ). The European Directive identifies geographical areas of risk exposure as monitoring/assessment zones to record the emission sources and levels of air pollution ( 27 ), whereas the USA establishes global geographical air quality criteria according to the severity of their air quality problem and records all sources of the pollutants and their precursors ( 27 ).

In this vein, funds have been financing, directly or indirectly, projects related to air quality along with the technical infrastructure to maintain good air quality. These plans focus on an inventory of databases from air quality environmental planning awareness campaigns. Moreover, pollution measures of air emissions may be taken for vehicles, machines, and industries in urban areas.

Technological innovation can only be successful if it is able to meet the needs of society. In this sense, technology must reflect the decision-making practices and procedures of those involved in risk assessment and evaluation and act as a facilitator in providing information and assessments to enable decision makers to make the best decisions possible. Summarizing the aforementioned in order to design an effective air quality control strategy, several aspects must be considered: environmental factors and ambient air quality conditions, engineering factors and air pollutant characteristics, and finally, economic operating costs for technological improvement and administrative and legal costs. Considering the economic factor, competitiveness through neoliberal concepts is offering a solution to environmental problems ( 22 ).

The development of environmental governance, along with technological progress, has initiated the deployment of a dialogue. Environmental politics has created objections and points of opposition between different political parties, scientists, media, and governmental and non-governmental organizations ( 22 ). Radical environmental activism actions and movements have been created ( 22 ). The rise of the new information and communication technologies (ICTs) are many times examined as to whether and in which way they have influenced means of communication and social movements such as activism ( 28 ). Since the 1990s, the term “digital activism” has been used increasingly and in many different disciplines ( 29 ). Nowadays, multiple digital technologies can be used to produce a digital activism outcome on environmental issues. More specifically, devices with online capabilities such as computers or mobile phones are being used as a way to pursue change in political and social affairs ( 30 ).

In the present paper, we focus on the sources of environmental pollution in relation to public health and propose some solutions and interventions that may be of interest to environmental legislators and decision makers.

Sources of Exposure

It is known that the majority of environmental pollutants are emitted through large-scale human activities such as the use of industrial machinery, power-producing stations, combustion engines, and cars. Because these activities are performed at such a large scale, they are by far the major contributors to air pollution, with cars estimated to be responsible for approximately 80% of today's pollution ( 31 ). Some other human activities are also influencing our environment to a lesser extent, such as field cultivation techniques, gas stations, fuel tanks heaters, and cleaning procedures ( 32 ), as well as several natural sources, such as volcanic and soil eruptions and forest fires.

The classification of air pollutants is based mainly on the sources producing pollution. Therefore, it is worth mentioning the four main sources, following the classification system: Major sources, Area sources, Mobile sources, and Natural sources.

Major sources include the emission of pollutants from power stations, refineries, and petrochemicals, the chemical and fertilizer industries, metallurgical and other industrial plants, and, finally, municipal incineration.

Indoor area sources include domestic cleaning activities, dry cleaners, printing shops, and petrol stations.

Mobile sources include automobiles, cars, railways, airways, and other types of vehicles.

Finally, natural sources include, as stated previously, physical disasters ( 33 ) such as forest fire, volcanic erosion, dust storms, and agricultural burning.

However, many classification systems have been proposed. Another type of classification is a grouping according to the recipient of the pollution, as follows:

Air pollution is determined as the presence of pollutants in the air in large quantities for long periods. Air pollutants are dispersed particles, hydrocarbons, CO, CO 2 , NO, NO 2 , SO 3 , etc.

Water pollution is organic and inorganic charge and biological charge ( 10 ) at high levels that affect the water quality ( 34 , 35 ).

Soil pollution occurs through the release of chemicals or the disposal of wastes, such as heavy metals, hydrocarbons, and pesticides.

Air pollution can influence the quality of soil and water bodies by polluting precipitation, falling into water and soil environments ( 34 , 36 ). Notably, the chemistry of the soil can be amended due to acid precipitation by affecting plants, cultures, and water quality ( 37 ). Moreover, movement of heavy metals is favored by soil acidity, and metals are so then moving into the watery environment. It is known that heavy metals such as aluminum are noxious to wildlife and fishes. Soil quality seems to be of importance, as soils with low calcium carbonate levels are at increased jeopardy from acid rain. Over and above rain, snow and particulate matter drip into watery ' bodies ( 36 , 38 ).

Lastly, pollution is classified following type of origin:

Radioactive and nuclear pollution , releasing radioactive and nuclear pollutants into water, air, and soil during nuclear explosions and accidents, from nuclear weapons, and through handling or disposal of radioactive sewage.

Radioactive materials can contaminate surface water bodies and, being noxious to the environment, plants, animals, and humans. It is known that several radioactive substances such as radium and uranium concentrate in the bones and can cause cancers ( 38 , 39 ).

Noise pollution is produced by machines, vehicles, traffic noises, and musical installations that are harmful to our hearing.

The World Health Organization introduced the term DALYs. The DALYs for a disease or health condition is defined as the sum of the Years of Life Lost (YLL) due to premature mortality in the population and the Years Lost due to Disability (YLD) for people living with the health condition or its consequences ( 39 ). In Europe, air pollution is the main cause of disability-adjusted life years lost (DALYs), followed by noise pollution. The potential relationships of noise and air pollution with health have been studied ( 40 ). The study found that DALYs related to noise were more important than those related to air pollution, as the effects of environmental noise on cardiovascular disease were independent of air pollution ( 40 ). Environmental noise should be counted as an independent public health risk ( 40 ).

Environmental pollution occurs when changes in the physical, chemical, or biological constituents of the environment (air masses, temperature, climate, etc.) are produced.

Pollutants harm our environment either by increasing levels above normal or by introducing harmful toxic substances. Primary pollutants are directly produced from the above sources, and secondary pollutants are emitted as by-products of the primary ones. Pollutants can be biodegradable or non-biodegradable and of natural origin or anthropogenic, as stated previously. Moreover, their origin can be a unique source (point-source) or dispersed sources.

Pollutants have differences in physical and chemical properties, explaining the discrepancy in their capacity for producing toxic effects. As an example, we state here that aerosol compounds ( 41 – 43 ) have a greater toxicity than gaseous compounds due to their tiny size (solid or liquid) in the atmosphere; they have a greater penetration capacity. Gaseous compounds are eliminated more easily by our respiratory system ( 41 ). These particles are able to damage lungs and can even enter the bloodstream ( 41 ), leading to the premature deaths of millions of people yearly. Moreover, the aerosol acidity ([H+]) seems to considerably enhance the production of secondary organic aerosols (SOA), but this last aspect is not supported by other scientific teams ( 38 ).

Climate and Pollution

Air pollution and climate change are closely related. Climate is the other side of the same coin that reduces the quality of our Earth ( 44 ). Pollutants such as black carbon, methane, tropospheric ozone, and aerosols affect the amount of incoming sunlight. As a result, the temperature of the Earth is increasing, resulting in the melting of ice, icebergs, and glaciers.

In this vein, climatic changes will affect the incidence and prevalence of both residual and imported infections in Europe. Climate and weather affect the duration, timing, and intensity of outbreaks strongly and change the map of infectious diseases in the globe ( 45 ). Mosquito-transmitted parasitic or viral diseases are extremely climate-sensitive, as warming firstly shortens the pathogen incubation period and secondly shifts the geographic map of the vector. Similarly, water-warming following climate changes leads to a high incidence of waterborne infections. Recently, in Europe, eradicated diseases seem to be emerging due to the migration of population, for example, cholera, poliomyelitis, tick-borne encephalitis, and malaria ( 46 ).

The spread of epidemics is associated with natural climate disasters and storms, which seem to occur more frequently nowadays ( 47 ). Malnutrition and disequilibration of the immune system are also associated with the emerging infections affecting public health ( 48 ).

The Chikungunya virus “took the airplane” from the Indian Ocean to Europe, as outbreaks of the disease were registered in Italy ( 49 ) as well as autochthonous cases in France ( 50 ).

An increase in cryptosporidiosis in the United Kingdom and in the Czech Republic seems to have occurred following flooding ( 36 , 51 ).

As stated previously, aerosols compounds are tiny in size and considerably affect the climate. They are able to dissipate sunlight (the albedo phenomenon) by dispersing a quarter of the sun's rays back to space and have cooled the global temperature over the last 30 years ( 52 ).

Air Pollutants

The World Health Organization (WHO) reports on six major air pollutants, namely particle pollution, ground-level ozone, carbon monoxide, sulfur oxides, nitrogen oxides, and lead. Air pollution can have a disastrous effect on all components of the environment, including groundwater, soil, and air. Additionally, it poses a serious threat to living organisms. In this vein, our interest is mainly to focus on these pollutants, as they are related to more extensive and severe problems in human health and environmental impact. Acid rain, global warming, the greenhouse effect, and climate changes have an important ecological impact on air pollution ( 53 ).

Particulate Matter (PM) and Health

Studies have shown a relationship between particulate matter (PM) and adverse health effects, focusing on either short-term (acute) or long-term (chronic) PM exposure.

Particulate matter (PM) is usually formed in the atmosphere as a result of chemical reactions between the different pollutants. The penetration of particles is closely dependent on their size ( 53 ). Particulate Matter (PM) was defined as a term for particles by the United States Environmental Protection Agency ( 54 ). Particulate matter (PM) pollution includes particles with diameters of 10 micrometers (μm) or smaller, called PM 10 , and extremely fine particles with diameters that are generally 2.5 micrometers (μm) and smaller.

Particulate matter contains tiny liquid or solid droplets that can be inhaled and cause serious health effects ( 55 ). Particles <10 μm in diameter (PM 10 ) after inhalation can invade the lungs and even reach the bloodstream. Fine particles, PM 2.5 , pose a greater risk to health ( 6 , 56 ) ( Table 1 ).

Penetrability according to particle size.

Multiple epidemiological studies have been performed on the health effects of PM. A positive relation was shown between both short-term and long-term exposures of PM 2.5 and acute nasopharyngitis ( 56 ). In addition, long-term exposure to PM for years was found to be related to cardiovascular diseases and infant mortality.

Those studies depend on PM 2.5 monitors and are restricted in terms of study area or city area due to a lack of spatially resolved daily PM 2.5 concentration data and, in this way, are not representative of the entire population. Following a recent epidemiological study by the Department of Environmental Health at Harvard School of Public Health (Boston, MA) ( 57 ), it was reported that, as PM 2.5 concentrations vary spatially, an exposure error (Berkson error) seems to be produced, and the relative magnitudes of the short- and long-term effects are not yet completely elucidated. The team developed a PM 2.5 exposure model based on remote sensing data for assessing short- and long-term human exposures ( 57 ). This model permits spatial resolution in short-term effects plus the assessment of long-term effects in the whole population.

Moreover, respiratory diseases and affection of the immune system are registered as long-term chronic effects ( 58 ). It is worth noting that people with asthma, pneumonia, diabetes, and respiratory and cardiovascular diseases are especially susceptible and vulnerable to the effects of PM. PM 2.5 , followed by PM 10 , are strongly associated with diverse respiratory system diseases ( 59 ), as their size permits them to pierce interior spaces ( 60 ). The particles produce toxic effects according to their chemical and physical properties. The components of PM 10 and PM 2.5 can be organic (polycyclic aromatic hydrocarbons, dioxins, benzene, 1-3 butadiene) or inorganic (carbon, chlorides, nitrates, sulfates, metals) in nature ( 55 ).

Particulate Matter (PM) is divided into four main categories according to type and size ( 61 ) ( Table 2 ).

Types and sizes of particulate Matter (PM).

Gas contaminants include PM in aerial masses.

Particulate contaminants include contaminants such as smog, soot, tobacco smoke, oil smoke, fly ash, and cement dust.

Biological Contaminants are microorganisms (bacteria, viruses, fungi, mold, and bacterial spores), cat allergens, house dust and allergens, and pollen.

Types of Dust include suspended atmospheric dust, settling dust, and heavy dust.

Finally, another fact is that the half-lives of PM 10 and PM 2.5 particles in the atmosphere is extended due to their tiny dimensions; this permits their long-lasting suspension in the atmosphere and even their transfer and spread to distant destinations where people and the environment may be exposed to the same magnitude of pollution ( 53 ). They are able to change the nutrient balance in watery ecosystems, damage forests and crops, and acidify water bodies.

As stated, PM 2.5 , due to their tiny size, are causing more serious health effects. These aforementioned fine particles are the main cause of the “haze” formation in different metropolitan areas ( 12 , 13 , 61 ).

Ozone Impact in the Atmosphere

Ozone (O 3 ) is a gas formed from oxygen under high voltage electric discharge ( 62 ). It is a strong oxidant, 52% stronger than chlorine. It arises in the stratosphere, but it could also arise following chain reactions of photochemical smog in the troposphere ( 63 ).

Ozone can travel to distant areas from its initial source, moving with air masses ( 64 ). It is surprising that ozone levels over cities are low in contrast to the increased amounts occuring in urban areas, which could become harmful for cultures, forests, and vegetation ( 65 ) as it is reducing carbon assimilation ( 66 ). Ozone reduces growth and yield ( 47 , 48 ) and affects the plant microflora due to its antimicrobial capacity ( 67 , 68 ). In this regard, ozone acts upon other natural ecosystems, with microflora ( 69 , 70 ) and animal species changing their species composition ( 71 ). Ozone increases DNA damage in epidermal keratinocytes and leads to impaired cellular function ( 72 ).

Ground-level ozone (GLO) is generated through a chemical reaction between oxides of nitrogen and VOCs emitted from natural sources and/or following anthropogenic activities.

Ozone uptake usually occurs by inhalation. Ozone affects the upper layers of the skin and the tear ducts ( 73 ). A study of short-term exposure of mice to high levels of ozone showed malondialdehyde formation in the upper skin (epidermis) but also depletion in vitamins C and E. It is likely that ozone levels are not interfering with the skin barrier function and integrity to predispose to skin disease ( 74 ).

Due to the low water-solubility of ozone, inhaled ozone has the capacity to penetrate deeply into the lungs ( 75 ).

Toxic effects induced by ozone are registered in urban areas all over the world, causing biochemical, morphologic, functional, and immunological disorders ( 76 ).

The European project (APHEA2) focuses on the acute effects of ambient ozone concentrations on mortality ( 77 ). Daily ozone concentrations compared to the daily number of deaths were reported from different European cities for a 3-year period. During the warm period of the year, an observed increase in ozone concentration was associated with an increase in the daily number of deaths (0.33%), in the number of respiratory deaths (1.13%), and in the number of cardiovascular deaths (0.45%). No effect was observed during wintertime.

Carbon Monoxide (CO)

Carbon monoxide is produced by fossil fuel when combustion is incomplete. The symptoms of poisoning due to inhaling carbon monoxide include headache, dizziness, weakness, nausea, vomiting, and, finally, loss of consciousness.

The affinity of carbon monoxide to hemoglobin is much greater than that of oxygen. In this vein, serious poisoning may occur in people exposed to high levels of carbon monoxide for a long period of time. Due to the loss of oxygen as a result of the competitive binding of carbon monoxide, hypoxia, ischemia, and cardiovascular disease are observed.

Carbon monoxide affects the greenhouses gases that are tightly connected to global warming and climate. This should lead to an increase in soil and water temperatures, and extreme weather conditions or storms may occur ( 68 ).

However, in laboratory and field experiments, it has been seen to produce increased plant growth ( 78 ).

Nitrogen Oxide (NO 2 )

Nitrogen oxide is a traffic-related pollutant, as it is emitted from automobile motor engines ( 79 , 80 ). It is an irritant of the respiratory system as it penetrates deep in the lung, inducing respiratory diseases, coughing, wheezing, dyspnea, bronchospasm, and even pulmonary edema when inhaled at high levels. It seems that concentrations over 0.2 ppm produce these adverse effects in humans, while concentrations higher than 2.0 ppm affect T-lymphocytes, particularly the CD8+ cells and NK cells that produce our immune response ( 81 ).It is reported that long-term exposure to high levels of nitrogen dioxide can be responsible for chronic lung disease. Long-term exposure to NO 2 can impair the sense of smell ( 81 ).

However, systems other than respiratory ones can be involved, as symptoms such as eye, throat, and nose irritation have been registered ( 81 ).

High levels of nitrogen dioxide are deleterious to crops and vegetation, as they have been observed to reduce crop yield and plant growth efficiency. Moreover, NO 2 can reduce visibility and discolor fabrics ( 81 ).

Sulfur Dioxide (SO 2 )

Sulfur dioxide is a harmful gas that is emitted mainly from fossil fuel consumption or industrial activities. The annual standard for SO 2 is 0.03 ppm ( 82 ). It affects human, animal, and plant life. Susceptible people as those with lung disease, old people, and children, who present a higher risk of damage. The major health problems associated with sulfur dioxide emissions in industrialized areas are respiratory irritation, bronchitis, mucus production, and bronchospasm, as it is a sensory irritant and penetrates deep into the lung converted into bisulfite and interacting with sensory receptors, causing bronchoconstriction. Moreover, skin redness, damage to the eyes (lacrimation and corneal opacity) and mucous membranes, and worsening of pre-existing cardiovascular disease have been observed ( 81 ).

Environmental adverse effects, such as acidification of soil and acid rain, seem to be associated with sulfur dioxide emissions ( 83 ).

Lead is a heavy metal used in different industrial plants and emitted from some petrol motor engines, batteries, radiators, waste incinerators, and waste waters ( 84 ).

Moreover, major sources of lead pollution in the air are metals, ore, and piston-engine aircraft. Lead poisoning is a threat to public health due to its deleterious effects upon humans, animals, and the environment, especially in the developing countries.

Exposure to lead can occur through inhalation, ingestion, and dermal absorption. Trans- placental transport of lead was also reported, as lead passes through the placenta unencumbered ( 85 ). The younger the fetus is, the more harmful the toxic effects. Lead toxicity affects the fetal nervous system; edema or swelling of the brain is observed ( 86 ). Lead, when inhaled, accumulates in the blood, soft tissue, liver, lung, bones, and cardiovascular, nervous, and reproductive systems. Moreover, loss of concentration and memory, as well as muscle and joint pain, were observed in adults ( 85 , 86 ).

Children and newborns ( 87 ) are extremely susceptible even to minimal doses of lead, as it is a neurotoxicant and causes learning disabilities, impairment of memory, hyperactivity, and even mental retardation.

Elevated amounts of lead in the environment are harmful to plants and crop growth. Neurological effects are observed in vertebrates and animals in association with high lead levels ( 88 ).

Polycyclic Aromatic Hydrocarbons(PAHs)

The distribution of PAHs is ubiquitous in the environment, as the atmosphere is the most important means of their dispersal. They are found in coal and in tar sediments. Moreover, they are generated through incomplete combustion of organic matter as in the cases of forest fires, incineration, and engines ( 89 ). PAH compounds, such as benzopyrene, acenaphthylene, anthracene, and fluoranthene are recognized as toxic, mutagenic, and carcinogenic substances. They are an important risk factor for lung cancer ( 89 ).

Volatile Organic Compounds(VOCs)

Volatile organic compounds (VOCs), such as toluene, benzene, ethylbenzene, and xylene ( 90 ), have been found to be associated with cancer in humans ( 91 ). The use of new products and materials has actually resulted in increased concentrations of VOCs. VOCs pollute indoor air ( 90 ) and may have adverse effects on human health ( 91 ). Short-term and long-term adverse effects on human health are observed. VOCs are responsible for indoor air smells. Short-term exposure is found to cause irritation of eyes, nose, throat, and mucosal membranes, while those of long duration exposure include toxic reactions ( 92 ). Predictable assessment of the toxic effects of complex VOC mixtures is difficult to estimate, as these pollutants can have synergic, antagonistic, or indifferent effects ( 91 , 93 ).

Dioxins originate from industrial processes but also come from natural processes, such as forest fires and volcanic eruptions. They accumulate in foods such as meat and dairy products, fish and shellfish, and especially in the fatty tissue of animals ( 94 ).

Short-period exhibition to high dioxin concentrations may result in dark spots and lesions on the skin ( 94 ). Long-term exposure to dioxins can cause developmental problems, impairment of the immune, endocrine and nervous systems, reproductive infertility, and cancer ( 94 ).

Without any doubt, fossil fuel consumption is responsible for a sizeable part of air contamination. This contamination may be anthropogenic, as in agricultural and industrial processes or transportation, while contamination from natural sources is also possible. Interestingly, it is of note that the air quality standards established through the European Air Quality Directive are somewhat looser than the WHO guidelines, which are stricter ( 95 ).

Effect of Air Pollution on Health

The most common air pollutants are ground-level ozone and Particulates Matter (PM). Air pollution is distinguished into two main types:

Outdoor pollution is the ambient air pollution.

Indoor pollution is the pollution generated by household combustion of fuels.

People exposed to high concentrations of air pollutants experience disease symptoms and states of greater and lesser seriousness. These effects are grouped into short- and long-term effects affecting health.

Susceptible populations that need to be aware of health protection measures include old people, children, and people with diabetes and predisposing heart or lung disease, especially asthma.

As extensively stated previously, according to a recent epidemiological study from Harvard School of Public Health, the relative magnitudes of the short- and long-term effects have not been completely clarified ( 57 ) due to the different epidemiological methodologies and to the exposure errors. New models are proposed for assessing short- and long-term human exposure data more successfully ( 57 ). Thus, in the present section, we report the more common short- and long-term health effects but also general concerns for both types of effects, as these effects are often dependent on environmental conditions, dose, and individual susceptibility.

Short-term effects are temporary and range from simple discomfort, such as irritation of the eyes, nose, skin, throat, wheezing, coughing and chest tightness, and breathing difficulties, to more serious states, such as asthma, pneumonia, bronchitis, and lung and heart problems. Short-term exposure to air pollution can also cause headaches, nausea, and dizziness.

These problems can be aggravated by extended long-term exposure to the pollutants, which is harmful to the neurological, reproductive, and respiratory systems and causes cancer and even, rarely, deaths.

The long-term effects are chronic, lasting for years or the whole life and can even lead to death. Furthermore, the toxicity of several air pollutants may also induce a variety of cancers in the long term ( 96 ).

As stated already, respiratory disorders are closely associated with the inhalation of air pollutants. These pollutants will invade through the airways and will accumulate at the cells. Damage to target cells should be related to the pollutant component involved and its source and dose. Health effects are also closely dependent on country, area, season, and time. An extended exposure duration to the pollutant should incline to long-term health effects in relation also to the above factors.

Particulate Matter (PMs), dust, benzene, and O 3 cause serious damage to the respiratory system ( 97 ). Moreover, there is a supplementary risk in case of existing respiratory disease such as asthma ( 98 ). Long-term effects are more frequent in people with a predisposing disease state. When the trachea is contaminated by pollutants, voice alterations may be remarked after acute exposure. Chronic obstructive pulmonary disease (COPD) may be induced following air pollution, increasing morbidity and mortality ( 99 ). Long-term effects from traffic, industrial air pollution, and combustion of fuels are the major factors for COPD risk ( 99 ).

Multiple cardiovascular effects have been observed after exposure to air pollutants ( 100 ). Changes occurred in blood cells after long-term exposure may affect cardiac functionality. Coronary arteriosclerosis was reported following long-term exposure to traffic emissions ( 101 ), while short-term exposure is related to hypertension, stroke, myocardial infracts, and heart insufficiency. Ventricle hypertrophy is reported to occur in humans after long-time exposure to nitrogen oxide (NO 2 ) ( 102 , 103 ).

Neurological effects have been observed in adults and children after extended-term exposure to air pollutants.

Psychological complications, autism, retinopathy, fetal growth, and low birth weight seem to be related to long-term air pollution ( 83 ). The etiologic agent of the neurodegenerative diseases (Alzheimer's and Parkinson's) is not yet known, although it is believed that extended exposure to air pollution seems to be a factor. Specifically, pesticides and metals are cited as etiological factors, together with diet. The mechanisms in the development of neurodegenerative disease include oxidative stress, protein aggregation, inflammation, and mitochondrial impairment in neurons ( 104 ) ( Figure 1 ).

Impact of air pollutants on the brain.

Brain inflammation was observed in dogs living in a highly polluted area in Mexico for a long period ( 105 ). In human adults, markers of systemic inflammation (IL-6 and fibrinogen) were found to be increased as an immediate response to PNC on the IL-6 level, possibly leading to the production of acute-phase proteins ( 106 ). The progression of atherosclerosis and oxidative stress seem to be the mechanisms involved in the neurological disturbances caused by long-term air pollution. Inflammation comes secondary to the oxidative stress and seems to be involved in the impairment of developmental maturation, affecting multiple organs ( 105 , 107 ). Similarly, other factors seem to be involved in the developmental maturation, which define the vulnerability to long-term air pollution. These include birthweight, maternal smoking, genetic background and socioeconomic environment, as well as education level.

However, diet, starting from breast-feeding, is another determinant factor. Diet is the main source of antioxidants, which play a key role in our protection against air pollutants ( 108 ). Antioxidants are free radical scavengers and limit the interaction of free radicals in the brain ( 108 ). Similarly, genetic background may result in a differential susceptibility toward the oxidative stress pathway ( 60 ). For example, antioxidant supplementation with vitamins C and E appears to modulate the effect of ozone in asthmatic children homozygous for the GSTM1 null allele ( 61 ). Inflammatory cytokines released in the periphery (e.g., respiratory epithelia) upregulate the innate immune Toll-like receptor 2. Such activation and the subsequent events leading to neurodegeneration have recently been observed in lung lavage in mice exposed to ambient Los Angeles (CA, USA) particulate matter ( 61 ). In children, neurodevelopmental morbidities were observed after lead exposure. These children developed aggressive and delinquent behavior, reduced intelligence, learning difficulties, and hyperactivity ( 109 ). No level of lead exposure seems to be “safe,” and the scientific community has asked the Centers for Disease Control and Prevention (CDC) to reduce the current screening guideline of 10 μg/dl ( 109 ).

It is important to state that impact on the immune system, causing dysfunction and neuroinflammation ( 104 ), is related to poor air quality. Yet, increases in serum levels of immunoglobulins (IgA, IgM) and the complement component C3 are observed ( 106 ). Another issue is that antigen presentation is affected by air pollutants, as there is an upregulation of costimulatory molecules such as CD80 and CD86 on macrophages ( 110 ).

As is known, skin is our shield against ultraviolet radiation (UVR) and other pollutants, as it is the most exterior layer of our body. Traffic-related pollutants, such as PAHs, VOCs, oxides, and PM, may cause pigmented spots on our skin ( 111 ). On the one hand, as already stated, when pollutants penetrate through the skin or are inhaled, damage to the organs is observed, as some of these pollutants are mutagenic and carcinogenic, and, specifically, they affect the liver and lung. On the other hand, air pollutants (and those in the troposphere) reduce the adverse effects of ultraviolet radiation UVR in polluted urban areas ( 111 ). Air pollutants absorbed by the human skin may contribute to skin aging, psoriasis, acne, urticaria, eczema, and atopic dermatitis ( 111 ), usually caused by exposure to oxides and photochemical smoke ( 111 ). Exposure to PM and cigarette smoking act as skin-aging agents, causing spots, dyschromia, and wrinkles. Lastly, pollutants have been associated with skin cancer ( 111 ).

Higher morbidity is reported to fetuses and children when exposed to the above dangers. Impairment in fetal growth, low birth weight, and autism have been reported ( 112 ).

Another exterior organ that may be affected is the eye. Contamination usually comes from suspended pollutants and may result in asymptomatic eye outcomes, irritation ( 112 ), retinopathy, or dry eye syndrome ( 113 , 114 ).

Environmental Impact of Air Pollution

Air pollution is harming not only human health but also the environment ( 115 ) in which we live. The most important environmental effects are as follows.

Acid rain is wet (rain, fog, snow) or dry (particulates and gas) precipitation containing toxic amounts of nitric and sulfuric acids. They are able to acidify the water and soil environments, damage trees and plantations, and even damage buildings and outdoor sculptures, constructions, and statues.

Haze is produced when fine particles are dispersed in the air and reduce the transparency of the atmosphere. It is caused by gas emissions in the air coming from industrial facilities, power plants, automobiles, and trucks.

Ozone , as discussed previously, occurs both at ground level and in the upper level (stratosphere) of the Earth's atmosphere. Stratospheric ozone is protecting us from the Sun's harmful ultraviolet (UV) rays. In contrast, ground-level ozone is harmful to human health and is a pollutant. Unfortunately, stratospheric ozone is gradually damaged by ozone-depleting substances (i.e., chemicals, pesticides, and aerosols). If this protecting stratospheric ozone layer is thinned, then UV radiation can reach our Earth, with harmful effects for human life (skin cancer) ( 116 ) and crops ( 117 ). In plants, ozone penetrates through the stomata, inducing them to close, which blocks CO 2 transfer and induces a reduction in photosynthesis ( 118 ).

Global climate change is an important issue that concerns mankind. As is known, the “greenhouse effect” keeps the Earth's temperature stable. Unhappily, anthropogenic activities have destroyed this protecting temperature effect by producing large amounts of greenhouse gases, and global warming is mounting, with harmful effects on human health, animals, forests, wildlife, agriculture, and the water environment. A report states that global warming is adding to the health risks of poor people ( 119 ).

People living in poorly constructed buildings in warm-climate countries are at high risk for heat-related health problems as temperatures mount ( 119 ).

Wildlife is burdened by toxic pollutants coming from the air, soil, or the water ecosystem and, in this way, animals can develop health problems when exposed to high levels of pollutants. Reproductive failure and birth effects have been reported.

Eutrophication is occurring when elevated concentrations of nutrients (especially nitrogen) stimulate the blooming of aquatic algae, which can cause a disequilibration in the diversity of fish and their deaths.

Without a doubt, there is a critical concentration of pollution that an ecosystem can tolerate without being destroyed, which is associated with the ecosystem's capacity to neutralize acidity. The Canada Acid Rain Program established this load at 20 kg/ha/yr ( 120 ).

Hence, air pollution has deleterious effects on both soil and water ( 121 ). Concerning PM as an air pollutant, its impact on crop yield and food productivity has been reported. Its impact on watery bodies is associated with the survival of living organisms and fishes and their productivity potential ( 121 ).

An impairment in photosynthetic rhythm and metabolism is observed in plants exposed to the effects of ozone ( 121 ).

Sulfur and nitrogen oxides are involved in the formation of acid rain and are harmful to plants and marine organisms.

Last but not least, as mentioned above, the toxicity associated with lead and other metals is the main threat to our ecosystems (air, water, and soil) and living creatures ( 121 ).

In 2018, during the first WHO Global Conference on Air Pollution and Health, the WHO's General Director, Dr. Tedros Adhanom Ghebreyesus, called air pollution a “silent public health emergency” and “the new tobacco” ( 122 ).

Undoubtedly, children are particularly vulnerable to air pollution, especially during their development. Air pollution has adverse effects on our lives in many different respects.

Diseases associated with air pollution have not only an important economic impact but also a societal impact due to absences from productive work and school.

Despite the difficulty of eradicating the problem of anthropogenic environmental pollution, a successful solution could be envisaged as a tight collaboration of authorities, bodies, and doctors to regularize the situation. Governments should spread sufficient information and educate people and should involve professionals in these issues so as to control the emergence of the problem successfully.

Technologies to reduce air pollution at the source must be established and should be used in all industries and power plants. The Kyoto Protocol of 1997 set as a major target the reduction of GHG emissions to below 5% by 2012 ( 123 ). This was followed by the Copenhagen summit, 2009 ( 124 ), and then the Durban summit of 2011 ( 125 ), where it was decided to keep to the same line of action. The Kyoto protocol and the subsequent ones were ratified by many countries. Among the pioneers who adopted this important protocol for the world's environmental and climate “health” was China ( 3 ). As is known, China is a fast-developing economy and its GDP (Gross Domestic Product) is expected to be very high by 2050, which is defined as the year of dissolution of the protocol for the decrease in gas emissions.

A more recent international agreement of crucial importance for climate change is the Paris Agreement of 2015, issued by the UNFCCC (United Nations Climate Change Committee). This latest agreement was ratified by a plethora of UN (United Nations) countries as well as the countries of the European Union ( 126 ). In this vein, parties should promote actions and measures to enhance numerous aspects around the subject. Boosting education, training, public awareness, and public participation are some of the relevant actions for maximizing the opportunities to achieve the targets and goals on the crucial matter of climate change and environmental pollution ( 126 ). Without any doubt, technological improvements makes our world easier and it seems difficult to reduce the harmful impact caused by gas emissions, we could limit its use by seeking reliable approaches.

Synopsizing, a global prevention policy should be designed in order to combat anthropogenic air pollution as a complement to the correct handling of the adverse health effects associated with air pollution. Sustainable development practices should be applied, together with information coming from research in order to handle the problem effectively.

At this point, international cooperation in terms of research, development, administration policy, monitoring, and politics is vital for effective pollution control. Legislation concerning air pollution must be aligned and updated, and policy makers should propose the design of a powerful tool of environmental and health protection. As a result, the main proposal of this essay is that we should focus on fostering local structures to promote experience and practice and extrapolate these to the international level through developing effective policies for sustainable management of ecosystems.

Author Contributions

All authors listed have made a substantial, direct and intellectual contribution to the work, and approved it for publication.

Conflict of Interest

IM is employed by the company Delphis S.A. The remaining authors declare that the present review paper was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Discharge from a Chinese fertilizer factory winds its way toward the Yellow River. Like many of the world's rivers, pollution remains an ongoing problem.

Water pollution is a rising global crisis. Here’s what you need to know.

The world's freshwater sources receive contaminants from a wide range of sectors, threatening human and wildlife health.

From big pieces of garbage to invisible chemicals, a wide range of pollutants ends up in our planet's lakes, rivers, streams, groundwater, and eventually the oceans. Water pollution—along with drought, inefficiency, and an exploding population—has contributed to a freshwater crisis , threatening the sources we rely on for drinking water and other critical needs.

Research has revealed that one pollutant in particular is more common in our tap water than anyone had previously thought: PFAS, short for poly and perfluoroalkyl substances. PFAS is used to make everyday items resistant to moisture, heat, and stains; some of these chemicals have such long half-lives that they are known as "the forever chemical."

Safeguarding water supplies is important because even though nearly 70 percent of the world is covered by water, only 2.5 percent of it is fresh. And just one percent of freshwater is easily accessible, with much of it trapped in remote glaciers and snowfields.

Water pollution causes

Water pollution can come from a variety of sources. Pollution can enter water directly, through both legal and illegal discharges from factories, for example, or imperfect water treatment plants. Spills and leaks from oil pipelines or hydraulic fracturing (fracking) operations can degrade water supplies. Wind, storms, and littering—especially of plastic waste —can also send debris into waterways.

Thanks largely to decades of regulation and legal action against big polluters, the main cause of U.S. water quality problems is now " nonpoint source pollution ," when pollutants are carried across or through the ground by rain or melted snow. Such runoff can contain fertilizers, pesticides, and herbicides from farms and homes; oil and toxic chemicals from roads and industry; sediment; bacteria from livestock; pet waste; and other pollutants .

Finally, drinking water pollution can happen via the pipes themselves if the water is not properly treated, as happened in the case of lead contamination in Flint, Michigan , and other towns. Another drinking water contaminant, arsenic , can come from naturally occurring deposits but also from industrial waste.

Freshwater pollution effects

Water pollution can result in human health problems, poisoned wildlife, and long-term ecosystem damage. When agricultural and industrial runoff floods waterways with excess nutrients such as nitrogen and phosphorus, these nutrients often fuel algae blooms that then create dead zones , or low-oxygen areas where fish and other aquatic life can no longer thrive.

Algae blooms can create health and economic effects for humans, causing rashes and other ailments, while eroding tourism revenue for popular lake destinations thanks to their unpleasant looks and odors. High levels of nitrates in water from nutrient pollution can also be particularly harmful to infants , interfering with their ability to deliver oxygen to tissues and potentially causing " blue baby syndrome ." The United Nations Food and Agriculture Organization estimates that 38 percent of the European Union's water bodies are under pressure from agricultural pollution.

Globally, unsanitary water supplies also exact a health toll in the form of disease. At least 2 billion people drink water from sources contaminated by feces, according to the World Health Organization , and that water may transmit dangerous diseases such as cholera and typhoid.

Freshwater pollution solutions

In many countries, regulations have restricted industry and agricultural operations from pouring pollutants into lakes, streams, and rivers, while treatment plants make our drinking water safe to consume. Researchers are working on a variety of other ways to prevent and clean up pollution. National Geographic grantee Africa Flores , for example, has created an artificial intelligence algorithm to better predict when algae blooms will happen. A number of scientists are looking at ways to reduce and cleanup plastic pollution .

There have been setbacks, however. Regulation of pollutants is subject to changing political winds, as has been the case in the United States with the loosening of environmental protections that prevented landowners from polluting the country’s waterways.

Anyone can help protect watersheds by disposing of motor oil, paints, and other toxic products properly , keeping them off pavement and out of the drain. Be careful about what you flush or pour down the sink, as it may find its way into the water. The U.S. Environmental Protection Agency recommends using phosphate-free detergents and washing your car at a commercial car wash, which is required to properly dispose of wastewater. Green roofs and rain gardens can be another way for people in built environments to help restore some of the natural filtering that forests and plants usually provide.

For Hungry Minds

Related topics.

• WATER POLLUTION
• ENVIRONMENT AND CONSERVATION
• FRESH WATER
• GROUNDWATER
• WATER QUALITY
• WATER RESOURCES

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• Open access
• Published: 27 April 2021

Urbanization: an increasing source of multiple pollutants to rivers in the 21st century

• Maryna Strokal   ORCID: orcid.org/0000-0002-8063-7743 1 ,
• Zhaohai Bai   ORCID: orcid.org/0000-0001-7685-5441 2 ,
• Wietse Franssen 1 ,
• Nynke Hofstra 1 ,
• Albert A. Koelmans 3 ,
• Fulco Ludwig 1 ,
• Lin Ma   ORCID: orcid.org/0000-0003-1761-0158 2 ,
• Peter van Puijenbroek   ORCID: orcid.org/0000-0001-6370-2411 4 ,
• J. Emiel Spanier 1 ,
• Lucie C. Vermeulen   ORCID: orcid.org/0000-0002-8403-2442 5 ,
• Michelle T. H. van Vliet   ORCID: orcid.org/0000-0002-2597-8422 6 ,
• Jikke van Wijnen 7 &
• Carolien Kroeze 1  

npj Urban Sustainability volume  1 , Article number:  24 ( 2021 ) Cite this article

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Most of the global population will live in urban areas in the 21st century. We study impacts of urbanization on future river pollution taking a multi-pollutant approach. We quantify combined point-source inputs of nutrients, microplastics, a chemical (triclosan) and a pathogen ( Cryptosporidium ) to 10,226 rivers in 2010, 2050 and 2100, and show how pollutants are related. Our scenarios consider socio-economic developments and varying rates of urbanization and wastewater treatment. Today, river pollution in Europe, South-East Asia and North America is severe. In the future, around 80% of the global population is projected to live in sub-basins with multi-pollutant problems in our high urbanization scenarios. In Africa, future river pollution is projected to be 11–18 times higher than in 2010, making it difficult to meet Sustainable Development Goals. Avoiding future pollution is technically possible with advanced wastewater treatment in many regions. In Africa, however, clean water availability is projected to remain challenging. Our multi-pollutant approach could support effective water pollution assessment in urban areas.

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Introduction.

Urban areas currently accommodate more than half of the global population 1 and generate over two-thirds of the world gross domestic products (GDP) 2 , 3 . In 2050, more than two-thirds of the global population will live in cities 1 , 4 , 5 . Rapid urbanization creates opportunities for economic developments 6 , but may also increase the use of freshwater resources 4 , 6 , 7 , 8 , 9 . This will increase competition for water between cities and agriculture 4 . More urban waste is likely to result in contamination of water with multiple pollutants such as nutrients 10 and pathogens 11 , 12 from human excretion, plastics 13 , 14 , 15 , 16 , 17 , 18 , and chemicals 19 , 20 from personal care products. River pollution poses a threat to the availability of clean water in large parts of the world 7 , 21 , challenging the achievement of Sustainable Development Goal 6 (SDG, clean water for all) and 11 (sustainable cities). Recent studies on impacts of rapid urbanization on water stress or water scarcity worldwide exist 4 , but often ignore water quality 7 .

Previous global studies likely underestimate the impact of urbanization on water pollution because of their strong focus on single pollutants 10 , 16 , 20 , 22 , 23 , 24 (Fig. 1 ). Urbanization (e.g., sewer connections in cities) is, however, often a common, point source of multiple pollutants in rivers, contributing to multiple impacts. Examples are eutrophication problems caused by nitrogen (N) and phosphorus (P) in many world regions 25 , 26 , and diarrhea caused by pathogens (e.g., Cryptosporidium ) especially in developing countries 11 , 27 . A multi-pollutant approach is, thus, urgently needed to account for interactions between drivers of urbanization (e.g., population, economy) and pressures such as emissions of different pollutants 21 . This can help to identify effective solutions accounting for synergies and trade-offs in pollution control. Furthermore, reducing multiple pollutants in rivers from urban-related sources might be easier (e.g., improved wastewater treatment) than from diffuse sources such as agricultural runoff (e.g., delay effects of reduction options due to accumulation of substances in soils). This may have a positive effect on the overall water quality status depending on diffuse sources.

The figure shows a difference between single-pollutant approaches (most existing studies) and a multi-pollutant approach (this study) to assess the impacts of the rapid urbanization on future global river quality. We take N (nitrogen), P (phosphorus), pathogens and plastics as examples. Advances of the multi-pollutant approach are discussed in the main text.

In this paper, we study the impacts of urbanization on river pollution in the 21st century, taking a multi-pollutant perspective. We define multi-pollutant problems as increasing levels of more than one pollutant to rivers in future decades. We analyze, simultaneously, the following groups of pollutants: nutrients (N and P), pathogens (such as Cryptosporidium ), microplastics and chemicals (such as triclosan). These pollutants are selected because of their increasing pollution in many rivers worldwide 18 , 20 , 23 , 28 , 29 , 30 . Yet, these pollutants have common urban sources such as sewer systems (worldwide) and open defecation. We quantify point-source inputs of the pollutants to 10,226 rivers for 2010, 2050 and 2100 associated with urbanization: sewer systems and open defecation. For this, we use a global model of Strokal et al. 31 that takes the sub-basin scale modelling approach of Strokal et al. 32 for nutrients and integrates modelling approaches for other pollutants 18 , 20 , 23 (Supplementary Tables 1 , 2 and 3 ). We develop this model further for multiple-pollutants and future analyses based on evaluated, modelling approaches (see the “Methods” section).

To assess the impacts of urbanization, we develop five scenarios with different levels of urbanization and wastewater treatment rates (Fig. 2 ). The storylines are interpretations of the five Shared Socio-economic Pathways (SSPs) 33 , 34 , 35 , 36 (Supplementary Tables 4 , 5 and 6 ). These SSPs are five pathways with different levels of socio-economic challenges for mitigation and adaptation 33 , 34 , 35 , 36 . SSP1 is a Green Road pathway with low socio-economic challenges (e.g., low population growth), but with high economic and urbanization development. It is largely oriented towards achieving sustainable goals (see Supplementary Tables 4 , 5 and 6 ). SSP2 is a middle of the road pathway with medium challenges to mitigation and adaptation. Future trends will not be very different from historical trends. SSP3 is a Rocky Road pathway with high challenges to mitigation and adaptation. It is a world with difficulties to control the population growth and has low economic and urbanization development (see Supplementary Tables 4 , 5 and 6 ). SSP4 is a Road Divided pathway with high challenges to mitigation and low to adaptation. It has a large gap between urban and rural development with the high urbanization rates especially in urban areas. SSP5 is a taking the highway pathway with high challenges to mitigate, but low challenges to adapt. It is a word with priorities towards economy (see Supplementary Tables 4 , 5 and 6 ).

Low, moderate and high urbanization is defined here as the increasing number of urban people and total people with sewer connections (see a and b panels and Supplementary Tables 4 – 6 ). The number of people opens defecating directly to water is assumed to decrease with sewer connection. Higher sewer connections imply that more wastewater treatment plants will be constructed to maintain the increasing volumes of the waste (see the “Methods” section). Low, moderate and high wastewater treatment levels refer here to a shirt (low, moderate, high) towards a next treatment type: e.g., from primary to secondary to tertiary ( a , b , Supplementary Tables 4 – 6 ). This implies the low, moderate and high ambitions to improve wastewater treatment ( b ). Future years are 2050 and 2100. Supplementary Tables 1 – 6 give quantitative interpretations of the storylines for our multi-pollutant model (see also the “Methods” section). GDP is the gross domestic product. Sources for the technologies are in the main text and in Supplementary Table 3 .

Our five scenarios incorporate socio-economic pathways of SSPs, but with quantitative interpretations of aspects related to urbanization and wastewater treatment (see the “Methods” section). Our scenarios aim to show the impact of urbanization on multiple pollutants in rivers. Thus, the names of our five scenarios correspond to the different levels of urbanization and wastewater treatment: from low urbanization and low wastewater treatment rates towards high urbanization and high wastewater treatment rates. This results in the following scenarios: low urbanization and low wastewater treatment rates (Low urb –Low wwt , based on SSP3), moderate urbanization and moderate wastewater treatment rates (Mod urb –Mod wwt , based on SSP2), high urbanization and low wastewater treatment rates (High urb –Low wwt , based on SSP4), high urbanization and moderate wastewater treatment rates (High urb –Mod wwt , based on SSP5), and high urbanization and high wastewater treatment rates (High urb –High wwt , based on SSP1) (Fig. 2 ). The five scenarios consider interactions between global change (socio-economic pathways), urbanization, sanitation and wastewater treatment.

Low, moderate and high urbanization reflect different levels of increases in urban population, and, indirectly, people with sewer connections between 2010 and future years (see the “Methods” section). As a net effect, the number of people practicing open defecation (direct inputs of human waste to rivers) may decrease. Increasing sewer connections assume higher capacities of treatment plants to manage increasing volumes of the wastewater. Low, moderate and high rates of wastewater treatment are defined based on a shift towards a next treatment type: e.g., from primary (technologies with <10% removal rates 10 , 18 , 20 , low) to secondary (50% removal rates 10 , 18 , 20 , 37 , moderate) or to tertiary (>75% removal rates 10 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , high, see the “Methods” section). The differences between the Low urb –Low wwt, and High urb –Low wwt scenarios indicate the impact of urbanization in terms of increasing numbers of people with sewer connections with low ambitions to improve the wastewater treatment under different socio-economic developments. The Mod urb –Mod wwt scenario could be considered business as usual. The differences between the High urb –Low wwt , High urb –Mod wwt and High urb –High wwt scenarios indicate the impact of improving the wastewater treatment in highly urbanized areas. Details are given in the “Methods” section on qualitative and quantitative descriptions of the five urbanization scenarios.

River pollution today

River pollution in Europe, South-East Asia and North America is already severe today. For these regions, we calculate high inputs of N (>50 kg km −2  year −1 ), P (>30 kg km −2  year −1 ), triclosan (>10 g km −2  year −1 ), microplastics (>5 kg km −2  year −1 ) and Cryptosporidium (>100 × 10 17 oocysts km −2 year −1 ) to many rivers in 2010 (Fig. 3 ). These regions experience severe water pollution problems 9 , 16 , 21 , 25 , 45 , contributing to negative impacts 21 such as eutrophication 45 and waterborne diseases (South-East Asian countries). For African sub-basins, pollution levels are not as high as in those regions (Fig. 3 ). However, some impacts of polluted water on children’s health are already indicated 21 . Globally, 9.5 Tg of N, 1.6 Tg of P, 0.45 Tg of microplastics, 0.72 kton of triclosan and 1.6 × 10 17 oocysts of Cryptosporidium entered rivers in 2010 (Fig. 4 , Supplementary Table 7 ). More than half of these inputs are to rivers in South-East Asia. Most of the pollutants in rivers are from sewer systems (see details in Supplementary Figs. from 1 to 29 ). Exceptions are some sub-basins in Africa and South-East Asia where open defecation contributes to over 20% of N, P and Cryptosporidium to their rivers. Existing assessments 9 , 10 , 13 , 20 , 23 reveal similar global estimates, but with diverse spatial scales. Our consistent spatial and temporal scales increase the robustness of our comparisons between multiple pollutants worldwide (e.g., Fig. 4 ).

Units are kg km −2 of sub-basin area year −1 for nitrogen (N), phosphorus (P) and microplastics (MP), g km −2 of sub-basin area year −1 for triclosan (TCS) and 10 17 oocysts km −2 of sub-basin area year −1 for Cryptosporidium . Source: the global multi-pollutant model (model description is provided in the “Methods” section, and in Supplementary Tables 1 – 6 , model inputs are in Supplementary Figs. 1 – 14 ). Model uncertainties are discussed in the “Methods” section.

a – e Future trends for individual pollutants. Pies show the shares of the surface areas by region as % of the global surface area. Spatially explicit results are shown in Fig. 3 for 2010 and Fig. 5 for the future. The description of the scenarios is in Fig. 2 , in the “Methods” section and Supplementary Tables 1 – 6 . Source: the global multi-pollutant model (model description is provided in the “Methods” section, and in Supplementary Tables 1 – 6 , model inputs are in Supplementary Figs. 1 – 14 ). Model uncertainties are discussed in the “Methods” section.

High pollution levels result from the net effect of population densities, sewer connection rates (Supplementary Figs. 1 , 2 and 3 ), production of pollutants in human waste (Supplementary Figs. 4 , 5 , 6 , 7 and 8 for individual pollutants) and wastewater treatment efficiencies (Supplementary Figs. 9 , 10 , 11 , 12 and 13 for individual pollutants) in countries (Supplementary Figs. 14 and 15 ). For South-East Asia, high pollution levels are driven by high population densities (Supplementary Figs. 3 and 16 ). This region accommodates approximately half of the global population (3 billion people, Supplementary Fig. 1 ) on 12% of the global surface area (Fig. 4 ). For comparison, sub-basins of Europe (excluding Russia) and North America accommodate around 10% of the global population (0.8 billion people, Supplementary Fig. 1 ) on 20% of the global surface area (Fig. 4 ). Approximately 20% of the total population in 2010 was connected to sewer systems (Supplementary Fig. 1 ) with relatively low wastewater treatment efficiencies (removal levels <50% for most pollutants, Supplementary Figs. 9 – 13 ). For Europe and North America, the high pollution levels per km 2 of sub-basins are driven by high connection rates to sewer systems especially in urban areas. Here, over two-thirds of the population live in urban areas and are largely connected to sewer systems with removal efficiencies above 50% for the studied pollutants (Supplementary Figs. 9 – 13 ). Supplementary Fig. 17 shows the results of the sensitivity analysis indicating the importance of wastewater treatment and human development in river pollution (see the “Discussion” section).

Future river pollution globally

In the future, ~80% of the global population is projected to live in sub-basins with multi-pollutant problems (Figs. 5 and 6 ). These sub-basins cover over half of the global surface area (Fig. 6 ) for which inputs of more than one pollutant will increase at least 30% (Fig. 5 ) between 2010 and 2050 or 2100. This is for all scenarios, except for High urb –High wwt . In the scenario assuming low urbanization and low wastewater treatment (Low urb –Low wwt ), global inputs of most pollutants will less than double between 2010 and 2050 (Fig. 4 ). In this scenario, the population growth is high, and almost doubles between 2010 and 2100 (Supplementary Fig. 3 ). Approximately one-third of the total population globally will be connected to sewer systems. This number is much lower than in the other scenarios in 2100 (Supplementary Fig. 3 ). As a net effect of the low sewer connection (Supplementary Fig. 3 ) and low wastewater treatment (Supplementary Figs. 9 – 13 ), future inputs of pollutants to rivers from sewage are lower in the Low urb –Low wwt scenario than in the others (Fig. 3 ). However, as a trade-off, more nutrients and Cryptosporidium are projected to enter rivers from open defecation, mainly in developing countries (see Supplementary Figs. 14 and 15 ) compared to the other scenarios.

Maps show changes in inputs of pollutants to rivers during the periods of 2010–2050, 2010–2100 and 2050–2100 according to the five scenarios. We classify sub-basins based on the number of pollutants for which the increases are higher or lower than 30% (Note: 30% is arbitrary; see Supplementary Figs. 18 and 20 for results based on 10 and 50% thresholds). The pollutants include Cryptosporidium , microplastic, triclosan, nitrogen and phosphorus. More information is available in Supplementary Figs. 18 – 29 . The description of the five scenarios is in Fig. 2 , in the “Methods” section and Supplementary Tables 1 – 6 . Results for 2010 are in Fig. 3 . Source: the global multi-pollutant model (model description is provided in the “Methods” section, and in Supplementary Tables 1 – 6 , model inputs are in Supplementary Figs. 1 – 14 ). Model uncertainties are discussed in the “Methods” section.

Sub-basins are classified based on the number of pollutants for which the increases are higher or lower than 30% during the periods of 2010–2050, 2010–2100 and 2050–2100 according to the five scenarios. Graphs show the number of sub-basins ( a ), sub-basin areas ( b ), total population ( c ) and urban population ( d ) for the sub-basins with the increases of higher or lower than 30% (Note: 30% is arbitrary; see Supplementary Figs. 19 and 21 for results based on 10% and 50% thresholds). More information is available in Supplementary Figs. 18 – 29 . See Fig. 5 for the changes in inputs of pollutants during the periods of 2010–2050, 2010–2100 and 2050–2100. The description of the scenarios is in Fig. 2 , in the “Methods” section and Supplementary Tables 1 – 6 . Results for 2010 are in Fig. 3 . Source: the global multi-pollutant model (model description is provided in the “Methods” section, and in Supplementary Tables 1 – 6 , model inputs are in Supplementary Figs. 1 – 14 ). Model uncertainties are discussed in the “Methods” section.

The future inputs of most pollutants to rivers are projected to be higher in the scenarios with moderate (Mod urb –Mod wwt ) and high urbanization (High urb –Low wwt , High urb –Mod wwt , Fig. 4 ). The population grows not as fast as in the Low urb –Low wwt scenario, but the rate of urbanization is much higher, especially in the High urb –Low wwt and High urb –Mod wwt scenarios (Supplementary Tables 4 – 6 ). As a result, over two-thirds of the global population is projected to be connected to sewer systems in 2100 (Supplementary Fig. 3 ). Wastewater treatment efficiency is slightly improved (Mod urb –Mod wwt , High urb –Mod wwt ) depending on the economic development (Supplementary Figs. 9 – 13 ). As a net effect, the High urb –Low wwt and High urb –Mod wwt scenarios project, generally, higher inputs of most pollutants to rivers than the Low urb –Low wwt and Mod urb –Mod wwt scenarios (Fig. 4 ).

Pollutants differ in their future trends. For example, High urb –Low wwt projects the highest inputs of Cryptosporidium , microplastics and triclosan globally in 2100 compared to the other pollutants and scenarios (Fig. 4 ). For N and P, High urb -Low wwt and High urb -Mod wwt project somewhat similar amounts globally (Fig. 4 ). All these differences between pollutants and scenarios are a net effect of three important factors: socio-economic development (e.g., population, GDP), urbanization rates (population connected to sewer systems) and treatment efficiencies. For example, higher GDP results generally in higher N and P excretion rates per capita because of changes towards protein-rich diets 31 , 46 (Supplementary Figs. 4 – 5 ). Developed countries (Human Developing Index, HDI > 0.785) have generally lower infection rates, leading to less per capita excretion of Cryptosporidium 23 (Supplementary Fig. 8 ), but may lead to higher production of microplastics from car tyres 31 (Supplementary Fig. 7 ) as a result of industrialization. All these interactions are considered together with different trends in the population growth (Supplementary Fig. 3 ), urbanization rates (Supplementary Figs. 1 and 2 ) and treatment levels (Supplementary Figs. 9 – 13 ) among scenarios and regions.

Future river pollution in Africa

Future river pollution is projected to be 11–18 times higher than in 2010 in the scenario with high urbanization and low wastewater improvements (High urb –Low wwt ). This range is for increasing inputs of the five pollutants by at least 30% during the period of 2010–2100 (Fig. 5 ). Africa may become a major contributor to river pollution in the world (Fig. 4 ). For example, by 2100, up to half of the global inputs of multiple pollutants are projected in Africa in High urb –Low wwt (Fig. 4 ). For comparison: in 2010 the contribution of African rivers to the global river pollution was <5% (Fig. 4 ). All scenarios project increasing river pollution in the future for Africa (Figs. 5 and 6 ). This is largely associated with the projected population growth and assumed wastewater treatment. The African population is projected to more than double in many sub-basins during 2010–2100 in all scenarios (Supplementary Fig. 3 ). Many people will live in urban areas (High urb –Low wwt and High urb –Mod wwt , Supplementary Figs. 1 – 3 ). More people will inevitably generate more waste, and this may not be treated effectively enough (e.g., High urb –Low wwt ). This all explains the large future increases in river pollution in Africa (Fig. 5 ). In the low urbanization scenario (Low urb –Low wwt ), less people will live in urban areas, and a lower percentage of people will be connected to sewer systems. Thus, open defecation may continue in Low urb –Low wwt especially by 2050. This is an important source of nutrients and Cryptosporidium to African rivers in this scenario. Supplementary Figs. 18 , 19 , 20 and 21 show results for increasing inputs of the five pollutants by at least 10% and 50% during the period of 2010–2100. Supplementary Figs. 22 , 23 , 24 , 25 and 26 show future trends in river pollution by individual pollutants. Supplementary Figs. 27 , 28 and 29 show scenarios and sub-basins where open defecation is an important source of P, N and Cryptosporidium in rivers.

Future river pollution in Asia

Future river pollution is projected to be 2–3 times higher than in 2010 in the scenario with high urbanization and low wastewater improvements (High urb –Low wwt ). This range is for at least 30% increases in inputs of the five pollutants for the period 2010–2100 (Fig. 5 ). Exceptions are rivers in sub-basins of China (Fig. 5 ). These rivers are projected to be cleaner in 2100 than in 2050, but inputs of the pollutants may still be higher in 2100 than in 2010 in the urbanized scenarios with the low (High urb –Low wwt and Low urb –Low wwt ) and moderate (Mod urb –Mod wwt and High urb –Mod wwt ) wastewater treatment improvements (Fig. 5 ). The Chinese population is projected to decrease in the future in all scenarios (Supplementary Fig. 3 ). However, with the rapid urbanization (Supplementary Figs. 1 – 2 ), the wastewater treatment (Supplementary Figs. 9 – 13 ) may not keep up with the pollution loads. This explains higher river pollution levels. This is different for some other Asian countries such as India and Pakistan. By 2050, the total population of India and Pakistan will have increased (Supplementary Fig. 3 ). By 2100, the total population will have decreased or increased depending on the socio-economic development in the scenarios (Supplementary Fig. 3 , Supplementary Tables 4 – 6 for the scenario description). However, the wastewater treatment is poorer or absent compared to the Chinese sub-basins (Supplementary Figs. 9 – 13 ), resulting in more pollutants in rivers (Fig. 5 , Supplementary Figs. 18 – 21 ).

Future river pollution in Europe and North America

Many rivers in Europe and North America may be cleaner in the future. European rivers (Western, Northern and Southern) may get cleaner in the future because of high removal efficiencies to treat wastewater (Supplementary Figs. 9 – 13 ). However, in the High urb –Mod wwt scenario, high wastewater treatment efficiencies (>50% for all pollutants) may not be enough to reduce future pollution to the level below 2010. For American rivers, future trends differ largely between South and North in the scenarios with the low (Low urb –Low wwt ) and high (High urb –Low wwt ) urbanization trends. In the Low urb –Low wwt scenario, lower increases (<30%) in inputs of pollutants are projected for many Northern rivers whereas higher increases (>30%) for most Southern rivers (Fig. 5 , Supplementary Figs. 18 – 21 ). This difference can be explained by the higher population growth (Supplementary Figs. 1 – 3 ) and less efficient wastewater treatment (Supplementary Figs. 9 – 13 ) in South America compared to North America. In the High urb –Low wwt scenario, higher increases in river pollution are projected for South America by 2050, but lower by 2100. This is associated with the decreased population (Supplementary Fig. 3 ) and with the increased efficiencies of wastewater treatment between 2050 and 2100 (Supplementary Figs. 9 – 13 ). Rivers in Australia may be more polluted in the future (Fig. 5 ). Exceptions are the Low urb –Low wwt and High urb –Low wwt scenarios with less pollution in 2100 than in 2050. This is largely associated with the decreasing population during 2050–2100 (Supplementary Figs. 1 – 13 , 18 – 21 ).

Reducing future river pollution

Advanced wastewater treatment can reduce future river pollution in many world regions, but not in Africa (High urb –High wwt ). In High urb –High wwt, all developed countries (HDI > 0.785) will shift completely towards tertiary treatment with enough capacities and high efficiencies to remove pollutants from the wastewater (>75% for all pollutants, Supplementary Figs. 1 – 14 ). Examples of such technologies are annomox 47 for N, calcium precipitation for P 48 , disinfection by Ultraviolet radiation for Cryptosporidium 42 , reverse osmosis for nutrients 41 and microplastics 49 . Developing countries (HDI < 0.785) will also shift towards tertiary technologies, but in combination with secondary technologies 10 , 46 (Supplementary Figs. 1 – 14 ). Open defecation will stop by 2100. Thus, High urb –High wwt shows the technical potential of advanced technologies with enough treatment capacities to reduce future pollution from highly urbanized areas.

It will be difficult to reduce future river pollution in Africa to the level of 2010, even with advanced technologies (High urb –High wwt , Fig. 5 ). Inputs of most pollutants to many African rivers are projected to increase by at least 30% during 2010–2100 in High urb –High wwt (Fig. 5 ). The main reason is an increase in the total population, which is much higher (>doubling) than in other world regions (Supplementary Fig. 3 ). As a result, implementing advanced technologies in 2100 may help to reduce inputs of most pollutants to the level of 2050, but not to the level of 2010. For many other world’s rivers, advanced technologies with enough treatment capacities are projected to lower future inputs of pollutants in High urb –High wwt (Fig. 5 , Supplementary Fig. 20 ). This may have a positive impact on the overall pollution status depending also on the contribution of diffuse sources from agriculture. However, for some rivers in Asia (e.g. India, Pakistan), inputs of most pollutants from point sources will still increase by 2050, but may be lower by 2100 in High urb –High wwt (Fig. 5 ). Some rivers in North America, Middle Asia and Australia are projected to have higher inputs of pollutants in 2100 than in 2050, but lower than in 2010 (Fig. 5 , Supplementary Fig. 20 ). These trends are the net effect of the population growth, urbanization and wastewater treatment in High urb –High wwt (Figs. 2 , 5 and 6 ).

Scenario analyses are widely used to explore possible futures 1 , 34 , 36 , 50 , 51 , 52 . Our five scenarios are a combination of possible trends in urbanization, socio-economic development (existing SSPs 1 , 36 , 53 ) and our assumptions on sanitation, wastewater treatment capacities and removal efficiencies of pollutants. Our assumptions may, however, seem ambitious (Supplementary Tables 5 and 6 ). For example, we assume the full implementation of advanced technologies with enough treatment capacities in High urb –High wwt for all developed countries. We did this to show the effects of sustainable practices in urban areas on increasing the availability of clean water for people and nature. This assumption, however, might be ambitious to achieve. In our scenarios, we reflect a relation between urbanization (e.g., more urban people) and sewer connections (see High urb –Low wwt, High urb –Med wwt ) with sustainable urbanization practices (see High urb –High wwt ). This relation may, however, not emerge everywhere in the world. On the other hand, we explore possible futures; we do not state how likely or desirable these futures are. Our scenarios aim to identify impacts of future urbanization (e.g., differences between Low urb –Low wwt and High urb –Low wwt ) and the technical potentials of proven wastewater treatment technologies to reduce future river pollution from point sources (e.g., differences between High urb –Low wwt and High urb –High wwt ). Our insights may contribute to the formulation of sustainable urbanization practices where wastewater treatment is effective enough to reduce pollutants in the urban waste (e.g., SDG11) and thus to increase the availability of clean water in the future (e.g., SDG6).

Our global multi-pollutant model quantifies, simultaneously, five pollutants in rivers with consistent datasets in space and time. However, uncertainties exist. The model is developed based on existing, evaluated models for pollutants 11 , 18 , 20 , 23 , 29 , 32 (e.g., comparisons with observed concentrations and sensitivity analyses). We further evaluate our combined model using five approaches 54 (see the “Methods” section). First, we compare our model outputs with existing studies (see the “Methods” section, Supplementary Table 7 ), showing a good agreement for the five pollutants. Second, we compare the spatial pattern of pollution problems with existing models 8 , 9 , 10 , 11 , 12 , 16 , 55 , 56 , indicating the river pollution in densely populated and highly urbanized areas (Figs. 3 – 5 , Supplementary Tables 7 and 8 ). However, existing studies did not focus on a simultaneous reduction of the five pollutants from urbanized activities in the 21st century, which is a multi-pollutant perspective of our study. Third, we performed a sensitivity analysis for pollution hotspots. We define multi-pollutant hotspots as places with >30% increases in two or more pollutants between 2010 and future years (Fig. 5 ). This is an elegant way to combine the five pollutants. We realize that the 30% threshold is arbitrary. The results should, therefore, be interpreted as warning signals of future river pollution. In the sensitivity analysis, we changed the 30% threshold to 10% (Supplementary Figs. 18 – 19 ) and 50% (Supplementary Figs. 20 – 21 ). The results confirm the robustness of our main messages about future multi-pollutant hotspots. Fourth, we performed a sensitivity analysis for all important model inputs underlying the calculations (Supplementary Tables 9 , 10 , 11 and 12 , Supplementary Fig. 17 ). In total, 25 model inputs are changed with ±10%, resulting in 50 model runs for 10,226 sub-basins and five pollutants. The results show that the model is not very sensitive to changes in most model inputs. For most sub-basins, the model outputs are relatively sensitive to changes in <5 model inputs. These inputs are related to HDI, wastewater treatment types and removal efficiencies. The 10% changes in these inputs, resulted in up to 5% change in model output for sub-basins covering over two-thirds of the global surface area (see details in the “Methods” section for all sub-basins). Fifth, we compare model inputs with independent datasets (Supplementary Table 8 , Supplementary Figs. 15 and 16 ). All this gives trust in the model performance (see the “Methods” section).

Our results are future oriented. We focus on trends in future hotspots of multi-pollutant problems in the world. We believe that not all model uncertainties affect our main messages about trends. We also realize that our results are relatively sensitive to the assumptions on future HDI and wastewater treatment (see Approach 4 in the “Methods” section and sensitivity analysis). For HDI, we assumed an increase of 0, 10 and 20% between 2010 and 2050 and further increase by 2100 depending on scenario (Supplementary Tables 5 – 6 ). For wastewater treatment rates, we assumed a shift towards a next treatment type between 2010 and future years (e.g., 0–50% shift depending on scenario). To increase trust in our assumptions for future trends, we compared our model inputs with other independent studies. We did this for our five scenarios (Supplementary Table 8 , Supplementary Fig. 15 ). For example, future trends in our HDI between 2010 and future years are strongly in line with an independent study 57 ( R 2 above 0.88, see Supplementary Fig. 15 ). Crespo Cuaresma and Lutz 57 took into account differences in human development and their socio-economic wealth in projecting future HDI. Our wastewater treatment types in 2050 are also well compared with an independent study 10 (Supplementary Table 8 ).

Another potential source of uncertainties relates to the local variation in pollution levels. For example, sewage overflows may happen under heavy rain events, causing local peaks in water pollution. Such events are time dependent and may also contribute to global pollution levels 58 . We do not account for such local events in our model. We, however, believe that such omissions of events do not affect our messages for the multi-pollutants worldwide. This is because we explore future trends in the multi-pollutant hotspots worldwide that are influenced by global change, urbanization and wastewater treatment. Local analyses should, however, account for the impact of local events on local water quality (e.g., cities).

Our study aims to analyze the impact of the socio-economic drivers (e.g., GDP) and urbanization on future inputs of pollutants to rivers from point sources worldwide. However, we do not consider the transport of pollutants to rivers from agricultural fields, nor the impact of climate change on future river pollution. Next steps could be to further develop our global multi-pollutant model by calculating inputs of pollutants from agricultural fields and associated river export of pollutants. This will allow to explicitly combine the impact of both climate change and of socio-economic developments.

A multi-pollutant approach supports the search for effective solutions. A multi-pollutant approach might be more effective in reducing river pollution than a single-pollutant approach (Fig. 1 ). For example, reducing one pollutant may reduce (synergies) or increase (trade-offs) another pollutant. Our study serves as an illustrative example for the five pollutants. For example, increasing sewer connections may increase inputs of the five pollutants to rivers, but decrease inputs of N, P and Cryptosporidium from open defecation (Low urb –Low wwt ; trade-off). Higher economic developments may lead to less excreted Cryptosporidium per capita because of lower infection risks in developed countries 11 , 23 (Supplementary Fig. 8 ), but may generate more N and P in human excreta (Supplementary Figs. 4 – 5 ) as a result of protein-rich food consumption 10 , 46 (trade-off). Synergies also exist. For example, increasing sewer connections with advanced technologies and sufficient wastewater treatment capacities is projected to decrease the inputs of all five pollutants to many rivers in the future (High urb –High wwt ). This is also associated with synergies in treatment technologies to remove multiple pollutants. Some technologies are developed to target specific pollutants (e.g., N 47 , P 48 , Cryptosporidium 42 ). This implies that implementing technologies for one pollutant may not strongly influence another pollutant. However, technologies exist to treat more than one pollutant (e.g., 10 , 38 , 39 , 40 , 42 , 59 ). For example, secondary treatment with removal efficiencies of around 40–50% (assumed in Mod urb –Mod wwt and High urb –Mod wwt ) converts organic N into inorganic and gas, removing N from the waste 10 . They can also facilitate the biodegradation of triclosan 59 . Microplastics can host microorganisms (e.g., Cryptosporidium ) and serve as vectors for chemicals 15 , 49 , 60 . As a result, biofilms and flocs can form in, for example, activated sludge ponds and then settle down 49 . Triclosan can sorb to large particles and also settle down with other pollutants 38 , 39 , 59 . Advanced technologies (assumed in High urb –High wwt ) such as efficient ultrafiltration methods can reduce Cryptosporidium 42 and microplastics 49 , and reverse osmosis can recover nutrients 41 and reduce microplastics 49 . Nature-based solutions such as stabilization ponds and constructed wetlands are largely effective to reduce Cryptosporidium 42 and nutrients 61 . Accounting for synergies and trade-offs is essential to identify effective solutions for multiple pollutants. This can support the achievement of SDG11 for sustainable cities and SDG6 for clean water.

Our results can support policy assessment of water pollution in urban areas, and form the basis for actionable and region-specific solutions. We identify hotspots of urban-related river pollution and show possible effects of future urbanization on river quality under global change. This could help to prioritize short-term actions to avoid river pollution in the 21st century. Improving wastewater treatment is important to avoid multi-pollutant problems in an urbanized world (Fig. 5 , differences between High urb –High wwt and High urb –Low wwt ). Our sensitivity analysis indicates where improved wastewater treatment could have a larger impact (Supplementary Fig. 17 ). Our model indicates that water pollution is related to human development (expressed as human development index). This is important to realize when reducing Cryptosporidium and microplastics. Some countries in the world already introduced policies such as a ban of detergents and triclosan in products. Combing such policies with improved wastewater treatment may contribute to synergetic solutions for achieving SDGs and reducing river pollution from urban waste. For Africa, improving wastewater treatment may not be enough. Controlling the African population growth to reduce waste production in the future may be needed in urban and water policy assessments.

Our study quantifies future trends in inputs of five pollutants to rivers for five scenarios. We argue that a multi-pollutant perspective is needed in quantitative analyses of future trends in global change, urbanization, sanitation and wastewater treatment. We analyzed multiple pollutants simultaneously in a consistent way. We did this for 10,226 sub-basins for 2010, 2050 and 2100. Our insights are in how future trends differ between pollutants, sub-basins and how hotspots of multi-pollutant problems change in the 21st century. Our study provides an example of multi-pollutant problems from urban point sources. We show that future inputs of pollutants are projected to increase with increasing urbanization. We also show that it is technically possible to avoid these increases with advanced proven technologies to treat wastewater, except in Africa. In Africa, clean water availability is projected to remain a challenge because of the fast increasing population. This will consequently challenge the achievement of SDGs 6 and 11 in Africa. Our model may serve as an example for multi-pollutant modelling of diffuse sources such as agricultural runoff and other pollutants, such as pesticides 62 , antibiotics 24 and antimicrobial resistance. Another opportunity is to analyze the economic (e.g., costs), societal, institutional and political feasibilities of future pollution reduction options. This is important to identify region-specific solutions. Our long-term projections can help to increase the awareness of society and decision makers about pollution hotspots in the 21st century. This can facilitate short-term actions in different regions to avoid pollution in the future and contribute to achieve SDGs 6 and 11.

Model description and inputs

We used a model of Strokal et al. 31 that takes the sub-basin scale modelling approach of Strokal et al. 32 for nutrients and integrates modelling approaches for other pollutants 18 , 20 , 23 . We developed it further for future analyses of point-source inputs of pollutants to rivers (Supplementary Table 1 ). Our model quantifies inputs of five pollutants to 10,226 rivers: nitrogen (N), phosphorus (P), microplastics, triclosan and Cryptosporidium for 2010, 2050 and 2100. The model of Strokal et al. 31 was developed for 2010 taking the sub-basin modelling approach of Strokal, et al. 32 for N 29 , 32 , P 29 , 32 and integrating the existing modelling approaches for microplastics 18 , triclsan 20 and Cryptosporidium 23 . We developed the model for the years 2050 and 2100 based on the urbanization storylines of the SSPs and our assumptions. Our multi-pollutant model quantifies simultaneously annual inputs of the five pollutants to rivers at the sub-basin scale using the consistent spatial and temporal dataset for model inputs for 2010, 2050 and 2100. The model quantifies inputs of the five pollutants from sewer systems and open defecation. These are the point sources of the pollutants in rivers. Sewer systems discharge five pollutants to rivers. Open defecation is a point source of N, P and Cryptosporidium in our model. Model evaluation is presented below after the scenario descriptions.

Inputs of the pollutants to rivers from open defecation are quantified as a function of the population that is open defecating and the excretion or consumption rates of pollutants per person per year (Supplementary Tables 1 and 2 ). Inputs of pollutants from sewer systems are quantified as a function of the population that is connected to sewer systems, the excretion or consumption rates of pollutants per person per year and removal efficiencies of pollutants during treatment. We quantified inputs of the pollutants at 0.5° grid and then aggregate the results to 10,226 river sub-basins (Supplementary Table 1 ). Model inputs for 2010 are directly from Strokal, et al. 31 . Model inputs for 2050 and 2100 are based on the SSPs with different trends in urbanization and wastewater treatment (see scenario descriptions below).

Below, we explain how model inputs were derived (Supplementary Tables 1 – 6 ). Population for 2010, 2050 and 2100 are aggregated to 0.5° grid from the global, 0.125 degree cell database of Jones and O’Neill 53 . The number of people with sewer connections and open defecation are quantified at 0.5° grid using the population map of 0.5° grid and the fraction of people with sewer connections or open defecation. For 2010, the fraction of urban and rural people with sewer systems and open defecation were available by country from the Joint Monitoring Program (see details in Strokal et al. 31 and Hofstra and Vermeulen 11 ). We assigned the national values to grids of 0.5° grid. Then, we multiplied the number of people per grid (aggregated from Jones and O’Neill 53 ) with the fraction of people connected to sewer systems or open defecating (based on Hofstra and Vermeulen 11 ). For 2050 and 2100, we made assumptions for the fractions of people connected to sewer systems and with open defecation. These assumptions were based on storylines of SSPs for economy, population and urbanization (Fig. 2 , Supplementary Tables 4 – 6 ). Our assumptions differ among urban and rural people, and among developing and developed countries (see scenario descriptions below).

Excretion or consumption rates of pollutants were largely derived based on existing, evaluated approaches and sources. Excretion rates of N and P in human waste per person are quantified as a function of GDP (gross domestic product) at purchasing power parity, following the approach of Van Drecht et al. 46 , but adjusted to the unit of 2005 (see details in Strokal et al. 31 , Supplementary Tables 1 – 6 ). For 2010, 2050 and 2100, GDP at 0.5° grid was derived from the global SSP database with the projections from the International Institute for Applied Systems Analysis (IIASA, 63 ). P in detergents was from Van Drecht et al. 46 for the world regions (Supplementary Tables 1 – 6 ).

Excretion rates of Cryptosporidium were quantified based on the infection rate in developed (5%) and developing (10%) countries and the excretion rate per ill person (10 9 oocysts) according to Hofstra et al. 23 . For 2010, developed and developing countries were defined based on the Human Development Index (HDI), following the approach of Hofstra et al. 23 : HDI > 0.785 (developed) and HDI < 0.785 (developing). For 2050 and 2100, we made assumptions for HDI for countries depending on SSP storylines for the economy, population growth and urbanization (see scenario descriptions below and Supplementary Tables 4 – 6 ).

Consumption rates of microplastics per person per year were derived directly from Siegfried et al. 18 , but with some modifications (details are in Strokal et al. 31 ). Microplastics in sewer systems result from car tyres, PCPs (personal care products), household dusts and laundry. For PCPs, dust and laundry, consumption rates are 0.071, 0.08 and 0.12 kg of microplastics per person per year according to Siegfried, et al. 18 . We assumed that these values do not change over time. For tyres, this is different. Strokal et al. 31 assumed that developed countries will contribute more microplastics to sewage from car tyres as a side-effect of economic and infrastructural developments. Thus, we assigned 0.18 kg of microplastics from tyres per person for developed countries (HDI > 0.785) and 0.018 kg of microplastics from tyres per person for developing countries (HDI < 0.785) according to Strokal et al. 31 . We assumed changes in HDI by country in the future based on the SSPs storylines (see scenario descriptions below and Supplementary Tables 1 – 6 ).

Consumption rates of triclosan per person in the world were directly taken van Wijnen et al. 20 (0.5 kg per person per year for 2010). We assumed that the consumption rate will not change largely in the future and thus will remain as in 2010.

Removal efficiencies of pollutants during treatment were derived based on the existing studies. For N, P and Cryptosporidium , removal efficiencies were quantified by country using the national distribution of wastewater treatment types (primary, secondary, tertiary, no treatment) and their treatment efficiencies for pollutants, following the approaches of 11 , 23 , 46 (see Supplementary Tables 1 – 6 , Supplementary Figs. 1 – 14 ). The quantified national removal efficiencies were then assigned to corresponding grids of 0.5°. For 2010, national distributions of wastewater treatment types were derived from Hofstra and Vermeulen 11 with a few corrections for countries with missing data (details are in Strokal et al. 31 ). For 2050 and 2100, we assumed changes (low, moderate, high) in the distribution of the treatment types depending on the storylines of SSPs (see scenario descriptions below). These changes imply a shift towards a next treatment type: e.g., from primary to secondary to tertiary (Supplementary Tables 1 – 6 ). Removal efficiencies of pollutants for different treatment types were taken directly from literature (see Supplementary Table 3 ) and do not vary among years.

For triclosan and microplastics, removal efficiencies were quantified based on the approaches of van Wijnen et al. 20 and Siegfried et al. 18 (details are in Strokal et al. 31 ). We used the known removal rate of phosphorus to assume the removal of triclosan and microplastics. For our assumptions, we used data about the removal of triclosan and microplastics from literature 39 , 59 , 64 , 65 , 66 . Based on these data, we related average phosphorus removal in a watershed to triclosan removal. We formulated three classes of triclosan removal (0, 60 or 90%) and related these to known phosphorus removal in each sub-basin (details are in van Wijnen et al. 20 ). A similar approach was carried out for microplastics. We formulated four microplastics removal classes based on literature and related those to the known average phosphorus removal in each sub-basin 18 , 30 . These classes represent an average microplastics removal in each sub-basin. Microplastic removal depends on the size and density of the microplastics. Therefore, the removal at each individual WWTP will be dependent on these and other characteristics. In our study, on a global scale, we chose to assume average removal for each sub-basin.

Scenario description

Storylines of the five scenarios are summarized in Fig. 2 , Supplementary Tables 1 – 6 and Supplementary Figs. 1 – 14 . Our five scenarios are with low urbanization and low wastewater treatment rates (Low urb –Low wwt ), moderate urbanization and moderate wastewater treatment rates (Mod urb –Mod wwt ), high urbanization and low wastewater treatment rates (High urb –Low wwt ), high urbanization and moderate wastewater treatment rates (High urb –Mod wwt ), and high urbanization and high wastewater treatment rates (High urb –High wwt ) (Fig. 2 ). These scenarios follow future trends in the socio-economic development based on the existing SSPs 1 , 63 , combined with our assumptions for population with sewer connections, open defecation and for wastewater treatment capacities and technologies (Supplementary Tables 4 – 6 ). Below, we describe each scenario. Quantitative interpretations of the scenario assumptions are presented in Supplementary Tables 4 – 6 for 2050 and 2100, and inputs are given in Supplementary Figs. 1 – 14 .

The Low urb -Low wwt scenario is based on SSP3 projections for the socio-economic development (Fig. 2 , Supplementary Tables 4 – 6 ). The scenario assumes a fragmented world with difficulties to control population growth. In this world, It is projected a low economic development with low urbanization rates and high population growth. For example, a global population of approximately 12 billion people is projected for 2100, of which 58% will be urban (Supplementary Figs. 1 – 3 ). Low economic developments will not allow to develop technologies largely. For 2050, HDI is assumed to stay as in 2010 and increase by 10% between 2050 and 2100 on a county level (Supplementary Tables 4 – 6 ). The society will not focus on reducing or avoiding future river pollution. As a result, the fraction of the population with sewer connections (around one-third of the global population) and the treatment efficiencies of wastewater (e.g., 14–18% globally depending on pollutant) will remain in 2050 as in 2010 (Supplementary Figs. 3 , 9 – 13 ). The same holds for the wastewater treatment capacities. However, by 2100 more people may be connected to sewer systems (above one-third of the global population). This will result in higher capacities of the wastewater treatment plants with slightly improved treatment technologies (e.g., 21–24% of removal efficiencies globally depending on pollutant). However, future wastewater treatment efficiencies vary largely among world countries: e.g., 0–96% in 2100 depending on region and pollutant. In general, higher wastewater treatment efficiencies are projected for Europe, North America and Australia (Supplementary Figs. 9 – 13 ),

The Mod urb -Mod wwt scenario is based on SSP2 projections of the middle of the road for the socio-economic development (Fig. 2 , Supplementary Tables 4 – 6 ). The scenario assumes a moderate economic development, moderate urbanization rates and moderate population growth compared to the other scenarios. For example, 9 billion people are projected globally for 2100 and 80% will be urban (Supplementary Figs. 1 – 3 ). From 2010, HDI is assumed to increase by 10% by 2050 and further increase by 10% by 2100 on a county level (Supplementary Tables 4 – 6 ). Technological development follows the business as usual trends. As a result, more people will be connected to sewer systems than today (45% in 2050 and 68% in 2100 globally, Supplementary Fig. 3 ). A number of wastewater treatment plants will be constructed to maintain the increasing volume of the wastewater from connected population to sewer systems. The amount of waste that is collected will be treated with slightly improved wastewater treatment. For example, on average, 33–42% of removal efficiencies globally are projected for 2100. This range is for the five pollutants. The removal efficiencies vary largely among regions (0–97% depending on region and pollutant, Supplementary Figs. 9 – 13 ). The number of people connected to sewer systems will be larger for urban (over two-thirds) than for rural (less than one-third) population. Some people may still experience open defecation in 2050. By 2100, all people who opened defecated in 2050 will become connected to sewer systems.

The High urb -Low wwt scenario is based on SSP4 projections for the socio-economic development (Fig. 2 , Supplementary Tables 4 – 6 ). The scenario assumes a large gap between urban and rural developments. The economic development is projected to be moderate compared to the other scenarios. HDI is projected to increase as in the Mod urb –Mod wwt scenario (Supplementary Tables 1 – 3 , Supplementary Fig. 14 ). The population is projected to increase in the future, but not largely: e.g., around 30% between 2010 and 2100 globally. By 2100, the global population is projected to reach 9.3 billion people (Supplementary Fig. 3a ). However, the urban population will develop faster than the rural. Urbanization will be high: e.g., 76% and 90% of the global population will be urban in 2050 and 2100, respectively. As a result, the connection rate of the population to sewer systems will increase in the future for urban areas. For example, 80% of urban and 11% of rural population globally is projected to be connected to sewer systems in 2100 (Supplementary Figs. 1 – 3 ). Wastewater treatment capacities will be enough to maintain the waste from sewer systems and treatment will be improved as in the Mod urb -Mod wwt scenario. For rural areas, the fraction of people connected to sewer systems in 2050 may remain the same as in the Low urb -Low wwt scenario and will be improved by 2100 (Supplementary Tables 4 – 6 ). By 2050, some rural people may still open defecate. By 2100, all rural people who opened defecated in 2050 will become connected to sewer systems with better treatment.

The High urb –Mod wwt scenario is based on SSP5 projections for the socio-economic development (Supplementary Tables 4 – 6 , Fig. 2 ). The scenario assumes a high economic development with high urbanization and low population growth (Fig. 2 , Supplementary Table 4 ). For example, the total population globally is projected to increase by less than 10% between 2010 and 2100, reaching 7.4 billion people in 2100 (Supplementary Fig. 3a ). However, more than 90% of the global population will be urban in 2100. From 2010, HDI is assumed to increase by 20% by 2050 and further increase by 20% by 2100. The technological development is relatively high compared to the Mod urb -Mod wwt scenario. This will lead to a higher population with sewer connections. More than half of the global population will be connected to sewer systems in 2050. For 2100, this number is over two-thirds of the global population (Supplementary Figs. 1 – 3 ). The capacities of the wastewater treatment plants will be enough to manage the amount of waste from sewer systems. However, people will invest less in improving wastewater treatment. People will focus more on the economy rather than on reducing river pollution. As a result, wastewater treatment may follow the business as usual trends. For example, on average, 34–44% of the wastewater treatment efficiencies are projected globally for 2100. However, these efficiencies vary largely among regions (0–97% depending on area and pollutant, Supplementary Figs. 9 – 13 ). Furthermore, some people may still open defecate in nearby water systems in the future. By 2100, all people who opened defecated in 2050 will become connected to sewer systems.

The High urb –High wwt scenario is based on SSP1 projections for the socio-economic development (Fig. 2 , Supplementary Tables 4 – 6 ). The society will develop fast with high urbanization rates as comparable to the High urb –Mod wwt scenario. The global population is projected to reach 6.9 billion people in 2100 (Supplementary Fig. 3a ). The share of urban people globally is projected to be 77% in 2050 and 92% in 2100 (Supplementary Figs. 1 – 3 ). The share of the total connected people to sewer systems is projected to be 55% in 2050 and 82% in 2100. HDI is projected to increase in the same rate as in the High urb –Mod wwt scenario. However, in this world, a strong focus is on reducing or avoiding river pollution by using the best available advanced technologies in all areas. Technological development is high because of the high economic development. People will invest in improving technologies to treat wastewater with multiple pollutants. There will be opportunities to develop technologies for multiple pollutants and combine them with nature-based solutions. As a result, the wastewater treatment is assumed to be improved largely with high removal efficiencies (60–98% depending on year, area and pollutant, Supplementary Figs. 9 – 13 ).

Model evaluation

We evaluated the uncertainties in our model using four approaches following a building trust circle method 54 . This method has been applied in several water quality studies 32 , 67 , 68 . First, we compare model outputs with existing studies. Second, we compare the spatial pattern of the pollution problems with existing models for individual pollutants. Third, we perform a sensitivity analysis for pollution hotspots. Fourth, we perform a comprehensive sensitivity analysis for all important model inputs underlying the calculations. Fifth, we compare model inputs with independent datasets. Model validation against observed concentrations is, unfortunately, challenging. This is because our model does not quantify concentrations. Some of the existing global models calculate concentrations and were evaluated against observations (Supplementary Tables 7 – 8 ). Thus, we used those models to compare their results with ours for individual pollutants. Below, we elaborate on these five approaches. Details are in Supplementary Tables 7 – 12 and Supplementary Figs. 15 , 17 .

Approach 1: evaluating model outputs by comparing them with other models and studies for individual pollutants. This comparison is presented in Supplementary Table 7 . The results show that our model outputs for global inputs of nitrogen, phosphorus, microplastics, triclosan and Cryptosporidium are generally in line with other models and studies. For example, our model quantified 9.5 Tg of nitrogen to rivers from point sources in 2010. Other models quantified 6.4–10.4 Tg of nitrogen to rivers from points sources during 2000–2010 10 , 46 , 69 (Supplementary Table 7 ). For phosphorus, we quantified 1.6 Tg in 2010 whereas the other models quantified 1.0–1.5 Tg for the period of 2000–2010 10 , 46 , 69 . For 2050, we quantified 5.4–21.0 Tg of nitrogen and 0.6–3.5 Tg of phosphorus in 2050 (ranges for the five scenarios). van Puijenbroek et al. 10 quantified 13.5–17.9 Tg of nitrogen and 1.6–2.4 Tg of phosphorus in 2050 under the five SSPs. For Cryptosporidium , our model quantified 1.6 × 10 9 oocysts in 2010 which is 1.1–1.4 × 10 9 oocysts in another model in 2000–2010 11 , 23 (Supplementary Table 7 ). For 2050, our model quantified 0.4–2.9 × 10 9 oocysts (range for the five scenarios). For the Low urb -Low wwt scenario, this value is 2.44 × 10 9 oocysts, which is comparable with 2.28 × 10 9 oocysts from the other model 11 , 23 . To our knowledge, van Wijnen, et al. 20 is the only study quantifying triclosan export by rivers. Our estimates for Danube, Zhujiang and Ganges are comparable with estimates of van Wijnen et al. 20 (Supplementary Table 7 ). For microplastics, our model quantified 0.45 Tg entering rivers globally in 2010. Best 9 indicated loads of 0.41–4.00 Tg of plastics in 32 world’s rivers. This is higher than our estimate because Best 9 accounts for macro- and microplastics whereas we only consider microplastics. Avio et al. 13 indicated 0.27 Tg of plastics to oceans in some regions in the world. This is lower than our estimate because we quantify inputs of plastics to rivers and not to the oceans. The other reasons for the differences between our model and other studies are in data inputs and the spatial level of detail. We focus on sub-basin analyses with the consistent model inputs for multiple pollutants (Supplementary Table 7 , Supplementary Figs. 1 – 13 ).

Approach 2: evaluating model outputs by comparing the spatial variability in pollution hotspots with other studies. We reviewed the literature on pollution hotspots in the world for individual pollutants 8 , 9 , 10 , 11 , 12 , 16 , 55 , 56 , 70 . Our pollution hotspots for multiple pollutants are in line with the existing studies for individual pollutants. For example, most pollution often happens in densely populated and highly urbanized areas 8 , 9 , 10 , 11 , 12 , 16 , 55 , 56 . For example, Best 9 indicated over 80% of large transboundary rivers in the world with multiple pollutants. For many large cities in polluted regions, the demand for water already exceeds its availability. For example, water scarcity (ratio between the water demand and availability) has been already reported for cities in countries such as China (e.g., Shanghai, Beijing), India (e.g., Delhi, Kolkata, Bangalore, Hyderabad), Mexico, North America (e.g., Los Angeles) 70 . In the future, river pollution will further decrease the availability of clean water in many urban regions 4 , 7 , 8 , 71 . We show that it is technically possible to increase the availability of clean water with implementing advanced technologies (High urb _High wwt , Figs. 3 – 6 ). However, future analyses for multi-pollutant hotspots are lacking in the existing literature. A few global models performed future analysis for individual pollutants 10 , 11 , 18 , 20 where urbanization was taken into account by 2050. Their results indicate pollution hotspots where human activities are most intensive, which is in line with our study. However, studies exploring trends in multi-pollutant hotspots by 2100 do not exist. We explore trends in pollution hotspots for multi-pollutant problems covering the entire 21st century under the five scenarios with different socio-economic developments and levels of wastewater treatment.

Approach 3: evaluating model outputs for pollution hotspots by sensitivity analysis. In Fig. 5 , we showed multi-pollutant hotspots. These hotspots were defined as at least a 30% increase in inputs of more than one pollutant to rivers during 2010–2050, 2010–2100 and 2050–2100. This definition is modest and easier to understand and interpret. We checked if the pollution hotspots remain the same by changing a 30% increase to 10% (Supplementary Figs. 18 – 19 ) and 50% (Supplementary Fig. 20 – 21 ). Results of this sensitivity analysis indicate that our main messages stay the same: Africa will become a hotspot region with multiple pollutants in rivers in the 21st century and advanced technologies may help to reduce pollution in many rivers of the world.

Approach 4: evaluating model inputs by a sensitivity analysis. We performed a comprehensive sensitivity analysis for all important model inputs underlying the calculations. In total, there are 25 model input parameters included in this analysis. Every model input was changed by +10% and −10%. As a result, we did 50 runs of the model for the year 2010. We analyzed the results of the 50 runs for 10,226 sub-basins and five pollutants: Cryptosporidium , nitrogen, phosphorus, triclosan and microplastics. Details can be found in Supplementary Tables 9 – 12 and Supplementary Fig. 17 .

In general, increasing the model inputs (13 out of 25) that are responsible for excretion or consumption rates of pollutants in urban waste lead to more pollutants in rivers (Supplementary Tables 10 – 12 ). The opposite is observed when these model inputs are decreased. An exception is HDI for Cryptosporidium and microplastics. Model inputs that are responsible for wastewater treatments (6 out of 25) have the following effect on the model outputs: increases in these inputs lead to less pollutants in rivers and vice versa. Model inputs (6 out of 25) that are responsible for the number of people (urban and rural) connected to sewage systems have the following effect on the model outputs: increases in these inputs lead to more pollutants in rivers and vice versa (Supplementary Tables 10 – 12 ).

We find that model outputs are most sensitive to changes in 2–5 out of the 25 model inputs. The sensitivities vary among sub-basins and pollutants. These model inputs are HDI (sensitive for Cryptosporidium and microplastics), the fractions of secondary (sensitive for triclosan and microplastics) and tertiary (sensitive for all five pollutants) treatment, and the removal efficiencies of secondary (sensitive for triclosan and microplastics) and tertiary (sensitive for all five pollutants) treatment. We analyze model outputs for 10,226 sub-basins that are sensitive to changes in those 2–5 model inputs. Supplementary Tables 11 – 12 show the percentages of the sub-basin areas where model outputs for the five pollutants change by: <5%, 5–10%, 10–50% and >50%. Supplementary Fig. 17 shows the location of the sub-basins for which model outputs are sensitive to one or more model inputs.

The model results for sub-basins covering over two-thirds of the global surface area changed by less than 5% (Supplementary Tables 11 – 12 ). For ≤13% of the global surface area the model outputs changed between 5–10%. This is for all pollutants. For ≤8% of the global area, the changes are between 10–50% in the model outputs. Exceptions are Cryptosporidium and microplastics, which are relatively sensitive for HDI. In one-third of the sub-basin area the model output for Cryptosporidium changed 10–50% as a result of changes in HDI. For microplastic, the changes may be even higher. However, the number of basins with changes above 50% is small. These results show that HDI is an important model input for Cryptosporidium and microplastics (see Supplementary Tables 1 , 9 – 12 ).

Approach 5: evaluating model inputs by comparing them with independent datasets. We provide this comparison in Supplementary Table 8 , Supplementary Figs. 15 and 16 . Comparison results build trust in our model inputs. We compared the following important model inputs for 2010 and 2050 scenarios: total population, population with sewer connections, distribution of treatment types, removal efficiencies of pollutants, nutrients in human excretion (Supplementary Table 8 ). We compared these inputs with van Puijenbroek et al. 10 who recently published global analyses of nutrient inputs to rivers from point sources. We also compared our population from Jones and O’Neill 53 with another global dataset from Kc and Lutz 34 (Supplementary Fig. 16 ). Our model inputs are well compared with the mentioned studies. Furthermore, we compared our HDI index for 2010 and 2050 with the HDI index from Crespo Cuaresma and Lutz 57 (Supplementary Fig. 15 ). HDI is an important input in our model to quantify the excretion of Cryptosporidium . HDI influences the treatment developments and consumption of microplastics associated with the use of car tyres. Our values for HDI under the five scenarios are well compared with the values of Crespo Cuaresma and Lutz 57 ( R 2  > 0.88 for the five scenarios).

Results of these five approaches give us trust in using our multi-pollutant model to explore future trends in inputs of multiple pollutants to rivers from urbanization activities. All data are available in Strokal et al. 72 and Strokal et al. 73 .

Reporting summary

Further information on research design is available in the Nature Research Reporting Summary linked to this article.

Data availability

All the datasets generated and analysed during this study are publicly available in the Data Archiving and Networked Services (DANS Easy) repository: https://doi.org/10.17026/dans-zyx-jce3 73 . The data will be available for download from 01–04–2021. The data supporting the findings of this study are described in the following metadata record: https://doi.org/10.6084/m9.figshare.13333796 72 .

Code availability

All equations to the model are provided in the supplementary information files of this study and in the Data Archiving and Networked Services (DANS Easy) repository: https://doi.org/10.17026/dans-zyx-jce3 . The data will be available for download from 01–04–2021.

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Acknowledgements

M.S. (the corresponding author) was financially supported by a Veni-grant (0.16.Veni.198.001) and a KNAW-MOST SURE + project (5160957392).

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Water Systems and Global Change group, Wageningen University & Research, Wageningen, the Netherlands

Maryna Strokal, Wietse Franssen, Nynke Hofstra, Fulco Ludwig, J. Emiel Spanier & Carolien Kroeze

Key Laboratory of Agricultural Water Resources, Hebei Key Laboratory of Soil Ecology, Center for Agricultural Resources Research, Institute of Genetic and Developmental Biology, The Chinese Academy of Sciences, Hebei, China

Zhaohai Bai & Lin Ma

Aquatic Ecology and Water Quality Management group, Wageningen University & Research, Wageningen, the Netherlands

Albert A. Koelmans

PBL Netherlands Environmental Assessment Agency, the Hague, the Netherlands

Peter van Puijenbroek

Centre for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands

Lucie C. Vermeulen

Department of Physical Geography, Utrecht University, Utrecht, the Netherlands

Michelle T. H. van Vliet

Open University, Faculty of Science - Environmental Sciences Dept, Heerlen, the Netherlands

Jikke van Wijnen

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M.S. led this manuscript. M.S. was responsible for designing the manuscript, developing a multi-pollutant model, and analyzing and writing the manuscript. C.K. substantially assisted in designing the manuscript, developing the model and analyzing the results. Z.B., W.F., N.H., A.A.K., L.V., M.T.H.V., J.E.S. and J.W., contributed largely in developing the global multi-pollutant model that was used in the manuscript for future analyses of the impact of urbanization on river pollution. They and other authors provided information to the manuscript and advised on the analyses. All authors assisted the interpretations of the Shared Socio-economic Pathways. These pathways are used in the manuscript for multiple pollutants. All authors read and commented on the text. All authors approved the final version and were involved in the accountability for all aspects of the manuscript.

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Correspondence to Maryna Strokal .

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Strokal, M., Bai, Z., Franssen, W. et al. Urbanization: an increasing source of multiple pollutants to rivers in the 21st century. npj Urban Sustain 1 , 24 (2021). https://doi.org/10.1038/s42949-021-00026-w

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DOI : https://doi.org/10.1038/s42949-021-00026-w

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Essay on Pollution: Samples in 100, 150 and 200 Words

• Updated on  
• Apr 27, 2024

As the world embraced urbanization, mother nature witnessed the greener lands getting transformed into modern cities and metropolises. What followed is a trail of natural disasters signalling that something is wrong with the planet Earth. Pollution is increasingly asked under the writing section in school and college tests as well as competitive exams . This is because it is a relevant environmental issue today. This blog aims to help you with the necessary knowledge as well as tips and tricks to draft a well-written essay on pollution.

What is Pollution?

Pollution is the introduction of harmful materials into the environment. These materials are called pollutants. They can be created by human activity like trash and natural like volcanic ash. Pollutants damage the quality of water, air and land. Pollution is a global problem. Air and water carry pollution into the ocean currents and migrating fish. Pollution is among the many things that harm our planet- once greener and healthier than it is now. Pollution is a dangerous phenomenon that is contributing to an array of health issues.

Types of Pollution

In simple terms, pollution is defined as the contamination of the physical and biological constituents in the earth’s atmosphere. It affects human life and the natural environment to a very great extent. It degrades our natural resources, from the water we drink to the air we breathe. While writing an essay on Pollution, you must mention the major four types of pollution which are as follows:

• Air Pollution : Air pollution is the contamination of air in the atmosphere when harmful or excessive quantities of substances such as smoke and harmful gases from industries, CFCs and oxides produced by automobiles, the burning of solid wastes, etc. are introduced into the environment.
• Water Pollution : This refers to the contamination of natural resources of water, due to the addition of harmful chemical, biological or physical materials, which includes industrial wastes, oil spills, domestic and farm wastes, pesticides, as well as mining and agricultural wastes, to water resource which make it unusable.
• Soil Pollution : Land/Soil Pollution occurs due to the degradation of the earth’s surface by different commercial, industrial, agricultural and domestic activities. Causes of soil pollution also include mining, deforestation, dumping of e-waste and other industrial wastes, usage of harmful chemicals such as insecticides, pesticides, etc.
• Noise Pollution : Excess noise due to sounds created by machines, loudspeakers, microphones, loud music, noise from industries, construction and civil engineering works etc. lead to noise pollution.

Causes and Health Effects of Pollution

You can include various causes and health effects in your essay on Pollution from the following table:-

Sample Essay on Pollution in 100 Words

Pollution is the addition of unwanted substances which are incorporated into the environment that can damage our Earth. There are mainly four types of pollution, these include water pollution, air pollution, soil pollution, and noise pollution. One should note that any form of pollution is the result of careless activity carried out by man. We, humans daily dump waste directly into water bodies which leads to water pollution.

Vehicle emissions of smoke into the atmosphere impede the ability of all living things to breathe, leading to air pollution. Our garbage is dumped into landfills directly, which results in soil pollution. Although it cannot be seen, noise pollution is a severe type of pollution that can harm our ears.

Sample Essay on Pollution in 250-300 Words

The biggest threat planet Earth is facing is pollution. Unwanted substances leave a negative impact once released into an environment. There are four types of pollution air, water, land, and noise. Pollution affects the quality of life more than any human can imagine.

Due to air pollution, even teenage kids have developed various respiratory diseases. Water pollution has led to diseases in children. The waste we humans dump on the land or chemical fertilisers which are put on the land for agricultural purposes causes land/ soil pollution.

If the soil quality deteriorates due to such practices, the soil will become infertile and no crops could be grown in future. The government has launched various schemes over the years to fight pollution but individual efforts can also play a vital role.

Start by replacing plastic bags for shopping with cloth bags, stopping littering on roads and stopping wasting water are some of the basic things to start with that can lead to big changes in the environment.

Also Read: Essay on Green Energy PDF: 150 and 250 Words

Sample Essay on Pollution in 300-350 Words

One of the most critical threats faced by our planet in the present-day scenario. Environmental pollution is a global issue affecting people around the world. It is occurring in different forms, whether by affecting the air we breathe or the water resources we utilise for several purposes.

Air pollution came into being with an increase in the level of carbon dioxide, with the increase in pollutants which are contaminating the air and causing breathing discomfort as well as skin diseases to human beings. Talking about the other aspect, there is no life without water.

The water bodies are polluting and becoming unsafe for drinking or any other use because of industrial development, rapid urbanisation and various other reasons. Due to air pollution, diseases that can occur in human beings are asthma, various skin diseases, cancer, etc. Therefore, it is the essential need of the hour to take serious steps to reduce pollution to its core.

At a personal level, we can minimise environmental pollution by taking public transport or carpools to reduce vehicular smoke, avoiding firecrackers at festivals and celebrations can also cut down on air and noise pollution, and not using fertilisers and pesticides which can cause both water and soil pollution, and switching over to organic farming. The government can also bring strict rules and regulations to lessen industrial pollution.  

To sum up, any type of pollution is harmful to the environment with serious consequences like global warming, uneven climatic changes, etc. Due to our greediness and illegal human activities, the innocent lives of animals are lost. The time has come to join hands and work towards preserving and protecting the environment for the present as well as future generations.

Also Read: Essay on Environment: Examples and Tips

Short Essay on Pollution in English

Find a sample of a short essay on pollution below:

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Nikita Puri

Nikita is a creative writer and editor, who is always ready to learn new skills. She has great knowledge about study abroad universities, researching and writing blogs about them. Being a perfectionist, she has a habit of keeping her tasks complete on time before the OCD hits her. When Nikita is not busy working, you can find her eating while binge-watching The office. Also, she breathes music. She has done her bachelor's from Delhi University and her master's from Jamia Millia Islamia.

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pollution is very harmful to the environment. By pollution many diseases and virus like coronavirus. So JOIN THE GREEN REVOLUTION AND STOP POLLUTION

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Essay on Environmental Pollution

Students are often asked to write an essay on Environmental Pollution in their schools and colleges. And if you’re also looking for the same, we have created 100-word, 250-word, and 500-word essays on the topic.

Let’s take a look…

100 Words Essay on Environmental Pollution

Introduction.

Environmental pollution refers to the introduction of harmful substances into the environment. These pollutants can damage our natural resources, making them unsafe or unsuitable for use.

Types of Pollution

There are several types of pollution including air, water, soil, and noise pollution. Each type poses a unique threat to our environment and health.

Pollution affects every aspect of the environment. It harms wildlife, damages habitats, and can cause health problems in humans.

To protect our environment, we must reduce pollution. This involves conscious efforts from everyone to make sustainable choices.

Also check:

• Paragraph on Environmental Pollution
• Speech on Environmental Pollution

250 Words Essay on Environmental Pollution

Environmental pollution, a global menace, has been escalating at an alarming rate, posing a significant threat to our planet’s biodiversity and human health. The reckless exploitation of natural resources and relentless industrialization have been the primary contributors to this predicament.

Types of Environmental Pollution

Environmental pollution is primarily classified into air, water, and soil pollution. Air pollution, caused by the release of harmful gases and particulates, leads to respiratory diseases and global warming. Water pollution, on the other hand, is the result of dumping untreated waste and chemicals into water bodies, causing harm to aquatic life and contaminating drinking water. Soil pollution, caused by the excessive use of fertilizers and pesticides, affects plant growth and can lead to food contamination.

Impacts of Environmental Pollution

The impacts of environmental pollution are far-reaching and devastating. It not only disrupts ecosystems but also contributes to biodiversity loss, climate change, and human health issues. The increase in the Earth’s average temperature, melting ice caps, and rising sea levels are all consequences of pollution-induced global warming.

In conclusion, environmental pollution is a pressing issue that requires immediate attention and action. It is crucial for us, as responsible inhabitants of this planet, to adopt sustainable practices and encourage others to do the same. The future of our planet rests in our hands, and every step taken towards its preservation counts.

500 Words Essay on Environmental Pollution

Introduction to environmental pollution.

Environmental pollution, a global concern, is the introduction of contaminants into the natural environment causing adverse changes. These pollutants, usually generated by human activities, upset the balance of ecosystems, affecting their inhabitants and the environment itself.

The Different Types of Environmental Pollution

Environmental pollution manifests in various forms. Air pollution, caused by industrial emissions and vehicle exhaust, leads to global warming and respiratory illnesses. Water pollution, resulting from industrial waste, oil spills, and plastic waste, has devastating effects on aquatic life and water quality. Soil pollution, due to agricultural chemicals and waste disposal, impairs plant growth and can contaminate food sources. Noise pollution, often overlooked, can cause stress and hearing loss in both humans and animals.

The Impact of Environmental Pollution on Biodiversity

Environmental pollution severely affects biodiversity. Pollutants can cause immediate harm to organisms or subtly alter habitats over time, leading to reduced species diversity. For instance, oil spills can kill marine life instantly, while acid rain, a byproduct of air pollution, slowly makes lakes uninhabitable for many species. Such changes can disrupt ecosystems, as species interdependencies are complex and often poorly understood until a key species is lost.

Human Health and Environmental Pollution

Environmental pollution also poses significant risks to human health. Air pollution can lead to respiratory diseases and cancer, while contaminated water can cause gastrointestinal illnesses and other diseases. Prolonged exposure to noise pollution can result in hearing impairment and stress-related conditions. Furthermore, pollution-induced changes in the environment can lead to resource scarcity, contributing to conflicts and migration.

The Role of Legislation and Public Awareness

Effective legislation and public awareness are crucial in combating environmental pollution. Strict laws can regulate pollutant emissions, waste disposal, and resource use. However, laws alone are not enough. Public awareness and education about the harmful effects of pollution are necessary to stimulate behavioral changes. When individuals understand the impact of their actions, they are more likely to adopt sustainable practices.

Conclusion: The Urgency of Addressing Environmental Pollution

Environmental pollution is a complex issue that requires immediate attention. Its impacts are far-reaching, affecting biodiversity, human health, and social stability. While legislation can provide a framework for action, public awareness and individual responsibility are key to achieving a sustainable future. By understanding and addressing environmental pollution, we can help ensure the health and longevity of our planet.

That’s it! I hope the essay helped you.

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Air Pollution: Current and Future Challenges

Despite dramatic progress cleaning the air since 1970, air pollution in the United States continues to harm people’s health and the environment. Under the Clean Air Act, EPA continues to work with state, local and tribal governments, other federal agencies, and stakeholders to reduce air pollution and the damage that it causes.

• Learn about more about air pollution, air pollution programs, and what you can do.

Outdoor air pollution challenges facing the United States today include:

• Meeting health-based standards for common air pollutants
• Limiting climate change
• Reducing risks from toxic air pollutants
• Protecting the stratospheric ozone layer against degradation

Indoor air pollution, which arises from a variety of causes, also can cause health problems. For more information on indoor air pollution, which is not regulated under the Clean Air Act, see EPA’s indoor air web site .

Air Pollution Challenges: Common Pollutants

Great progress has been made in achieving national air quality standards, which EPA originally established in 1971 and updates periodically based on the latest science. One sign of this progress is that visible air pollution is less frequent and widespread than it was in the 1970s.

However, air pollution can be harmful even when it is not visible. Newer scientific studies have shown that some pollutants can harm public health and welfare even at very low levels. EPA in recent years revised standards for five of the six common pollutants subject to national air quality standards. EPA made the standards more protective because new, peer-reviewed scientific studies showed that existing standards were not adequate to protect public health and the environment.

Status of common pollutant problems in brief

Today, pollution levels in many areas of the United States exceed national air quality standards for at least one of the six common pollutants:

• Although levels of particle pollution and ground-level ozone pollution are substantially lower than in the past, levels are unhealthy in numerous areas of the country. Both pollutants are the result of emissions from diverse sources, and travel long distances and across state lines. An extensive body of scientific evidence shows that long- and short-term exposures to fine particle pollution, also known as fine particulate matter (PM 2.5 ), can cause premature death and harmful effects on the cardiovascular system, including increased hospital admissions and emergency department visits for heart attacks and strokes. Scientific evidence also links PM to harmful respiratory effects, including asthma attacks. Ozone can increase the frequency of asthma attacks, cause shortness of breath, aggravate lung diseases, and cause permanent damage to lungs through long-term exposure. Elevated ozone levels are linked to increases in hospitalizations, emergency room visits and premature death. Both pollutants cause environmental damage, and fine particles impair visibility. Fine particles can be emitted directly or formed from gaseous emissions including sulfur dioxide or nitrogen oxides. Ozone, a colorless gas, is created when emissions of nitrogen oxides and volatile organic compounds react.  
• For unhealthy peak levels of sulfur dioxide and nitrogen dioxide , EPA is working with states and others on ways to determine where and how often unhealthy peaks occur. Both pollutants cause multiple adverse respiratory effects including increased asthma symptoms, and are associated with increased emergency department visits and hospital admissions for respiratory illness. Both pollutants cause environmental damage, and are byproducts of fossil fuel combustion.  
• Airborne lead pollution, a nationwide health concern before EPA phased out lead in motor vehicle gasoline under Clean Air Act authority, now meets national air quality standards except in areas near certain large lead-emitting industrial facilities. Lead is associated with neurological effects in children, such as behavioral problems, learning deficits and lowered IQ, and high blood pressure and heart disease in adults.  
• The entire nation meets the carbon monoxide air quality standards, largely because of emissions standards for new motor vehicles under the Clean Air Act.

In Brief: How EPA is working with states and tribes to limit common air pollutants

• EPA's air research provides the critical science to develop and implement outdoor air regulations under the Clean Air Act and puts new tools and information in the hands of air quality managers and regulators to protect the air we breathe.  
• To reflect new scientific studies, EPA revised the national air quality standards for fine particles (2006, 2012), ground-level ozone (2008, 2015), sulfur dioxide (2010), nitrogen dioxide (2010), and lead (2008). After the scientific review, EPA decided to retain the existing standards for carbon monoxide.  EPA strengthened the air quality standards for ground-level ozone in October 2015 based on extensive scientific evidence about ozone’s effects.

EPA has designated areas meeting and not meeting the air quality standards for the 2006 and 2012 PM standards and the 2008 ozone standard, and has completed an initial round of area designations for the 2010 sulfur dioxide standard. The agency also issues rules or guidance for state implementation of the various ambient air quality standards – for example, in March 2015, proposing requirements for implementation of current and future fine particle standards. EPA is working with states to improve data to support implementation of the 2010 sulfur dioxide and nitrogen dioxide standards.

For areas not meeting the national air quality standards, states are required to adopt state implementation plan revisions containing measures needed to meet the standards as expeditiously as practicable and within time periods specified in the Clean Air Act (except that plans are not required for areas with “marginal” ozone levels).

• EPA is helping states to meet standards for common pollutants by issuing federal emissions standards for new motor vehicles and non-road engines, national emissions standards for categories of new industrial equipment (e.g., power plants, industrial boilers, cement manufacturing, secondary lead smelting), and technical and policy guidance for state implementation plans. EPA and state rules already on the books are projected to help 99 percent of counties with monitors meet the revised fine particle standards by 2020. The Mercury and Air Toxics Standards for new and existing power plants issued in December 2011 are achieving reductions in fine particles and sulfur dioxide as a byproduct of controls required to cut toxic emissions.  
• Vehicles and their fuels continue to be an important contributor to air pollution. EPA in 2014 issued standards commonly known as Tier 3, which consider the vehicle and its fuel as an integrated system, setting new vehicle emissions standards and a new gasoline sulfur standard beginning in 2017. The vehicle emissions standards will reduce both tailpipe and evaporative emissions from passenger cars, light-duty trucks, medium-duty passenger vehicles, and some heavy-duty vehicles. The gasoline sulfur standard will enable more stringent vehicle emissions standards and will make emissions control systems more effective. These rules further cut the sulfur content of gasoline. Cleaner fuel makes possible the use of new vehicle emission control technologies and cuts harmful emissions in existing vehicles. The standards will reduce atmospheric levels of ozone, fine particles, nitrogen dioxide, and toxic pollution.

Learn more about common pollutants, health effects, standards and implementation:

• fine particles
• ground-level ozone
• sulfur dioxide
• nitrogen dioxide
• carbon monoxide

Air Pollution Challenges: Climate Change

EPA determined in 2009 that emissions of carbon dioxide and other long-lived greenhouse gases that build up in the atmosphere endanger the health and welfare of current and future generations by causing climate change and ocean acidification. Long-lived greenhouse gases , which trap heat in the atmosphere, include carbon dioxide, methane, nitrous oxide, and fluorinated gases. These gases are produced by a numerous and diverse human activities.

In May 2010, the National Research Council, the operating arm of the National Academy of Sciences, published an assessment which concluded that “climate change is occurring, is caused largely by human activities, and poses significant risks for - and in many cases is already affecting - a broad range of human and natural systems.” 1 The NRC stated that this conclusion is based on findings that are consistent with several other major assessments of the state of scientific knowledge on climate change. 2

Climate change impacts on public health and welfare

The risks to public health and the environment from climate change are substantial and far-reaching. Scientists warn that carbon pollution and resulting climate change are expected to lead to more intense hurricanes and storms, heavier and more frequent flooding, increased drought, and more severe wildfires - events that can cause deaths, injuries, and billions of dollars of damage to property and the nation’s infrastructure.

Carbon dioxide and other greenhouse gas pollution leads to more frequent and intense heat waves that increase mortality, especially among the poor and elderly. 3 Other climate change public health concerns raised in the scientific literature include anticipated increases in ground-level ozone pollution 4 , the potential for enhanced spread of some waterborne and pest-related diseases 5 , and evidence for increased production or dispersion of airborne allergens. 6

Other effects of greenhouse gas pollution noted in the scientific literature include ocean acidification, sea level rise and increased storm surge, harm to agriculture and forests, species extinctions and ecosystem damage. 7 Climate change impacts in certain regions of the world (potentially leading, for example, to food scarcity, conflicts or mass migration) may exacerbate problems that raise humanitarian, trade and national security issues for the United States. 8

The U.S. government's May 2014 National Climate Assessment concluded that climate change impacts are already manifesting themselves and imposing losses and costs. 9 The report documents increases in extreme weather and climate events in recent decades, with resulting damage and disruption to human well-being, infrastructure, ecosystems, and agriculture, and projects continued increases in impacts across a wide range of communities, sectors, and ecosystems.

Those most vulnerable to climate related health effects - such as children, the elderly, the poor, and future generations - face disproportionate risks. 10 Recent studies also find that certain communities, including low-income communities and some communities of color (more specifically, populations defined jointly by ethnic/racial characteristics and geographic location), are disproportionately affected by certain climate-change-related impacts - including heat waves, degraded air quality, and extreme weather events - which are associated with increased deaths, illnesses, and economic challenges. Studies also find that climate change poses particular threats to the health, well-being, and ways of life of indigenous peoples in the U.S.

The National Research Council (NRC) and other scientific bodies have emphasized that it is important to take initial steps to reduce greenhouse gases without delay because, once emitted, greenhouse gases persist in the atmosphere for long time periods. As the NRC explained in a recent report, “The sooner that serious efforts to reduce greenhouse gas emissions proceed, the lower the risks posed by climate change, and the less pressure there will be to make larger, more rapid, and potentially more expensive reductions later.” 11

In brief: What EPA is doing about climate change

Under the Clean Air Act, EPA is taking initial common sense steps to limit greenhouse gas pollution from large sources:

EPA and the National Highway and Traffic Safety Administration between 2010 and 2012 issued the first national greenhouse gas emission standards and fuel economy standards for cars and light trucks for model years 2012-2025, and for medium- and heavy-duty trucks for 2014-2018.  Proposed truck standards for 2018 and beyond were announced in June 2015.  EPA is also responsible for developing and implementing regulations to ensure that transportation fuel sold in the United States contains a minimum volume of renewable fuel. Learn more about clean vehicles

EPA and states in 2011 began requiring preconstruction permits that limit greenhouse gas emissions from large new stationary sources - such as power plants, refineries, cement plants, and steel mills - when they are built or undergo major modification. Learn more about GHG permitting

• On August 3, 2015, President Obama and EPA announced the Clean Power Plan – a historic and important step in reducing carbon pollution from power plants that takes real action on climate change. Shaped by years of unprecedented outreach and public engagement, the final Clean Power Plan is fair, flexible and designed to strengthen the fast-growing trend toward cleaner and lower-polluting American energy. With strong but achievable standards for power plants, and customized goals for states to cut the carbon pollution that is driving climate change, the Clean Power Plan provides national consistency, accountability and a level playing field while reflecting each state’s energy mix. It also shows the world that the United States is committed to leading global efforts to address climate change. Learn more about the Clean Power Plan, the Carbon Pollution Standards, the Federal Plan, and model rule for states

The Clean Power Plan will reduce carbon pollution from existing power plants, the nation’s largest source, while maintaining energy reliability and affordability.  The Clean Air Act creates a partnership between EPA, states, tribes and U.S. territories – with EPA setting a goal, and states and tribes choosing how they will meet it.  This partnership is laid out in the Clean Power Plan.

Also on August 3, 2015, EPA issued final Carbon Pollution Standards for new, modified, and constructed power plants, and proposed a Federal Plan and model rules to assist states in implementing the Clean Power Plan.

On February 9, 2016, the Supreme Court stayed implementation of the Clean Power Plan pending judicial review. The Court’s decision was not on the merits of the rule. EPA firmly believes the Clean Power Plan will be upheld when the merits are considered because the rule rests on strong scientific and legal foundations.

On October 16, 2017, EPA  proposed to repeal the CPP and rescind the accompanying legal memorandum.

EPA is implementing its Strategy to Reduce Methane Emissions released in March 2014. In January 2015 EPA announced a new goal to cut methane emissions from the oil and gas sector by 40 – 45 percent from 2012 levels by 2025, and a set of actions by EPA and other agencies to put the U.S. on a path to achieve this ambitious goal. In August 2015, EPA proposed new common-sense measures to cut methane emissions, reduce smog-forming air pollution and provide certainty for industry through proposed rules for the oil and gas industry . The agency also proposed to further reduce emissions of methane-rich gas from municipal solid waste landfills . In March 2016 EPA launched the National Gas STAR Methane Challenge Program under which oil and gas companies can make, track and showcase ambitious commitments to reduce methane emissions.

EPA in July 2015 finalized a rule to prohibit certain uses of hydrofluorocarbons -- a class of potent greenhouse gases used in air conditioning, refrigeration and other equipment -- in favor of safer alternatives. The U.S. also has proposed amendments to the Montreal Protocol to achieve reductions in HFCs internationally.

Learn more about climate science, control efforts, and adaptation on EPA’s climate change web site

Air Pollution Challenges: Toxic Pollutants

While overall emissions of air toxics have declined significantly since 1990, substantial quantities of toxic pollutants continue to be released into the air. Elevated risks can occur in urban areas, near industrial facilities, and in areas with high transportation emissions.

Numerous toxic pollutants from diverse sources

Hazardous air pollutants, also called air toxics, include 187 pollutants listed in the Clean Air Act. EPA can add pollutants that are known or suspected to cause cancer or other serious health effects, such as reproductive effects or birth defects, or to cause adverse environmental effects.

Examples of air toxics include benzene, which is found in gasoline; perchloroethylene, which is emitted from some dry cleaning facilities; and methylene chloride, which is used as a solvent and paint stripper by a number of industries. Other examples of air toxics include dioxin, asbestos, and metals such as cadmium, mercury, chromium, and lead compounds.

Most air toxics originate from manmade sources, including mobile sources such as motor vehicles, industrial facilities and small “area” sources. Numerous categories of stationary sources emit air toxics, including power plants, chemical manufacturing, aerospace manufacturing and steel mills. Some air toxics are released in large amounts from natural sources such as forest fires.

Health risks from air toxics

EPA’s most recent national assessment of inhalation risks from air toxics 12 estimated that the whole nation experiences lifetime cancer risks above ten in a million, and that almost 14 million people in more than 60 urban locations have lifetime cancer risks greater than 100 in a million. Since that 2005 assessment, EPA standards have required significant further reductions in toxic emissions.

Elevated risks are often found in the largest urban areas where there are multiple emission sources, communities near industrial facilities, and/or areas near large roadways or transportation facilities. Benzene and formaldehyde are two of the biggest cancer risk drivers, and acrolein tends to dominate non-cancer risks.

In brief: How EPA is working with states and communities to reduce toxic air pollution

EPA standards based on technology performance have been successful in achieving large reductions in national emissions of air toxics. As directed by Congress, EPA has completed emissions standards for all 174 major source categories, and 68 categories of small area sources representing 90 percent of emissions of 30 priority pollutants for urban areas. In addition, EPA has reduced the benzene content in gasoline, and has established stringent emission standards for on-road and nonroad diesel and gasoline engine emissions that significantly reduce emissions of mobile source air toxics. As required by the Act, EPA has completed residual risk assessments and technology reviews covering numerous regulated source categories to assess whether more protective air toxics standards are warranted. EPA has updated standards as appropriate. Additional residual risk assessments and technology reviews are currently underway.

EPA also encourages and supports area-wide air toxics strategies of state, tribal and local agencies through national, regional and community-based initiatives. Among these initiatives are the National Clean Diesel Campaign , which through partnerships and grants reduces diesel emissions for existing engines that EPA does not regulate; Clean School Bus USA , a national partnership to minimize pollution from school buses; the SmartWay Transport Partnership to promote efficient goods movement; wood smoke reduction initiatives; a collision repair campaign involving autobody shops; community-scale air toxics ambient monitoring grants ; and other programs including Community Action for a Renewed Environment (CARE). The CARE program helps communities develop broad-based local partnerships (that include business and local government) and conduct community-driven problem solving as they build capacity to understand and take effective actions on addressing environmental problems.

Learn more about air toxics, stationary sources of emissions, and control efforts Learn more about mobile source air toxics and control efforts

Air Pollution Challenges: Protecting the Stratospheric Ozone Layer

The  ozone (O 3 ) layer  in the stratosphere protects life on earth by filtering out harmful ultraviolet radiation (UV) from the sun. When chlorofluorocarbons (CFCs) and other ozone-degrading chemicals  are emitted, they mix with the atmosphere and eventually rise to the stratosphere. There, the chlorine and the bromine they contain initiate chemical reactions that destroy ozone. This destruction has occurred at a more rapid rate than ozone can be created through natural processes, depleting the ozone layer.

The toll on public health and the environment

Higher levels of  ultraviolet radiation  reaching Earth's surface lead to health and environmental effects such as a greater incidence of skin cancer, cataracts, and impaired immune systems. Higher levels of ultraviolet radiation also reduce crop yields, diminish the productivity of the oceans, and possibly contribute to the decline of amphibious populations that is occurring around the world.

In brief: What’s being done to protect the ozone layer

Countries around the world are phasing out the production of chemicals that destroy ozone in the Earth's upper atmosphere under an international treaty known as the Montreal Protocol . Using a flexible and innovative regulatory approach, the United States already has phased out production of those substances having the greatest potential to deplete the ozone layer under Clean Air Act provisions enacted to implement the Montreal Protocol. These chemicals include CFCs, halons, methyl chloroform and carbon tetrachloride. The United States and other countries are currently phasing out production of hydrochlorofluorocarbons (HCFCs), chemicals being used globally in refrigeration and air-conditioning equipment and in making foams. Phasing out CFCs and HCFCs is also beneficial in protecting the earth's climate, as these substances are also very damaging greenhouse gases.

Also under the Clean Air Act, EPA implements regulatory programs to:

Ensure that refrigerants and halon fire extinguishing agents are recycled properly.

Ensure that alternatives to ozone-depleting substances (ODS) are evaluated for their impacts on human health and the environment.

Ban the release of ozone-depleting refrigerants during the service, maintenance, and disposal of air conditioners and other refrigeration equipment.

Require that manufacturers label products either containing or made with the most harmful ODS.

These vital measures are helping to protect human health and the global environment.

The work of protecting the ozone layer is not finished. EPA plans to complete the phase-out of ozone-depleting substances that continue to be produced, and continue efforts to minimize releases of chemicals in use. Since ozone-depleting substances persist in the air for long periods of time, the past use of these substances continues to affect the ozone layer today. In our work to expedite the recovery of the ozone layer, EPA plans to augment CAA implementation by:

Continuing to provide forecasts of the expected risk of overexposure to UV radiation from the sun through the UV Index, and to educate the public on how to protect themselves from over exposure to UV radiation.

Continuing to foster domestic and international partnerships to protect the ozone layer.

Encouraging the development of products, technologies, and initiatives that reap co-benefits in climate change and energy efficiency.

Learn more About EPA’s Ozone Layer Protection Programs

Some of the following links exit the site

1 National Research Council (2010), Advancing the Science of Climate Change , National Academy Press, Washington, D.C., p. 3.

2 National Research Council (2010), Advancing the Science of Climate Change , National Academy Press, Washington, D.C., p. 286.

3 USGCRP (2009).  Global Climate Change Impacts in the United States . Karl, T.R., J.M. Melillo, and T.C. Peterson (eds.). United States Global Change Research Program. Cambridge University Press, New York, NY, USA.

4 CCSP (2008).  Analyses of the effects of global change on human health and welfare and human systems . A Report by the U.S. Climate Change Science Program and the Subcommittee on Global Change Research. Gamble, J.L. (ed.), K.L. Ebi, F.G. Sussman, T.J. Wilbanks, (Authors). U.S. Environmental Protection Agency, Washington, DC, USA.

5 Confalonieri, U., B. Menne, R. Akhtar, K.L. Ebi, M. Hauengue, R.S. Kovats, B. Revich and A. Woodward (2007). Human health. In:  Climate Change 2007: Impacts, Adaptation and Vulnerability  .  Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change  Parry, M.L., O.F. Canziani, J.P. Palutikof, P.J. van der Linden and C.E. Hanson, (eds.), Cambridge University Press, Cambridge, United Kingdom.

7 An explanation of observed and projected climate change and its associated impacts on health, society, and the environment is included in the EPA’s Endangerment Finding and associated technical support document (TSD). See EPA, “ Endangerment and Cause or Contribute Findings for Greenhouse Gases under Section 202(a) of the Clean Air Act ,” 74 FR 66496, Dec. 15, 2009. Both the Federal Register Notice and the Technical Support Document (TSD) for Endangerment and Cause or Contribute Findings are found in the public docket, Docket No. EPA-OAR-2009-0171.

8 EPA, Endangerment Finding , 74 FR 66535.

9 . U.S. Global Change Research Program, Climate Change Impacts in the United States: The Third National Climate Assessment , May 2014.

10 EPA, Endangerment Finding , 74 FR 66498.

11 National Research Council (2011) America’s Climate Choices: Report in Brief , Committee on America’s Climate Choices, Board on Atmospheric Sciences and Climate, Division on Earth and Life Studies, The National Academies Press, Washington, D.C., p. 2.

12 EPA, 2005 National-Scale Air Toxics Assessment (2011).

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• Environmental Pollution Essay

Essay on Environmental Pollution

The environment is the surrounding of an organism. The environment in which an organism lives is made up of various components like air, water, land, etc. These components are found in fixed proportions to create a harmonious balance in the environment for the organism to live in. Any kind of undesirable and unwanted change in the proportions of these components can be termed as pollution. This issue is increasing with every passing year. It is an issue that creates economic, physical, and social troubles. The environmental problem that is worsening with each day needs to be addressed so that its harmful effects on humans as well as the planet can be discarded.

Causes of Environmental Pollution 

With the rise of the industries and the migration of people from villages to cities in search of employment, there has been a regular increase in the problem of proper housing and unhygienic living conditions. These reasons have given rise to factors that cause pollution. 

Environmental pollution is of five basic types namely, Air, Water, Soil, and Noise pollution. 

Air Pollution: Air pollution is a major issue in today’s world. The smoke pouring out of factory chimneys and automobiles pollute the air that we breathe in. Gases like carbon dioxide, carbon monoxide, and sulphur dioxide are emitted with this smoke which mixes with air and causes great harm to the human body, flora, and fauna. The dry-farm waste, dry grass, leaves, and coal used as domestic fuels in our villages also produce harmful gases. Acid rain occurs due to an excess of sulphur dioxide in the air.

The Main Sources of Air Pollution are as Follows:  

Automobile pollution 

Industrial air pollution 

Burning garbage 

Brick kilns 

Indoor air pollution 

Decomposed animals and plants 

Radioactive elements

Water Pollution: Water pollution is one of the most serious environmental issues. The waste products from the growing industries and sewage water are not treated properly before disposing of the wastewater into the rivers and other water bodies, thus leading to water pollution. Agricultural processes with excess fertilizers and pesticides also pollute the water bodies. 

The Main Sources of Water Pollution as Follows:  

Marine commerce. 

Industrial effluents joining seas and oceans. 

Dumping of radioactive substances into seawater. 

Sewage is disposed of into the sea by rivers. 

Offshore oil rigs. 

Recreational activities. 

Agricultural pollutants are disposed of into the water bodies.

Soil or Land Pollution: Soil pollution or land pollution results from the deposition of solid waste, accumulation of biodegradable material, deposition of chemicals with poisonous chemical compositions, etc on the open land. Waste materials such as plastics, polythene, and bottles, cause land pollution and render the soil infertile. Moreover, the dumping of dead bodies of animals adds to this issue. Soil pollution causes several diseases in man and animals like Cholera, Dysentery, Typhoid, etc.

The Main Causes of Soil Pollution are as Follows:  

Industrial waste 

Urban commercial and domestic waste 

Chemical fertilizers 

Biomedical waste 

Noise Pollution: With an increasing population, urbanization, and industrialization, noise pollution is becoming a serious form of pollution affecting human life, health, and comfort in daily life. Horns of vehicles, loudspeakers, music systems, and industrial activities contribute to noise pollution. 

The Main Sources of Noise Pollution as Follows:  

The machines in the factories and industries produce whistling sounds, crushing noise, and thundering sounds. 

Loudspeakers, horns of vehicles. 

Blasting of rocks and earth, drilling tube wells, ventilation fans, and heavy earth-moving machinery at construction sites.

How Pollution Harms Health and Environment

The lives of people and other creatures are affected by environmental pollution, both directly and indirectly. For centuries, these living organisms have coexisted with humans on the planet. 

1. Effect on the Environment

Smog is formed when carbon and dust particles bind together in the air, causing respiratory problems, haze, and smoke. These are created by the combustion of fossil fuels in industrial and manufacturing facilities and vehicle combustion of carbon fumes. 

Furthermore, these factors impact the immune systems of birds, making them carriers of viruses and diseases. It also has an impact on the body's system and organs. 

2.  Land, Soil, and Food Effects 

The degradation of human organic and chemical waste harms the land and soil. It also releases chemicals into the land and water. Pesticides, fertilisers, soil erosion, and crop residues are the main causes of land and soil pollution. 

3. Effects on water 

Water is easily contaminated by any pollutant, whether it be human waste or factory chemical discharge. We also use this water for crop irrigation and drinking. They, too, get polluted as a result of infection. Furthermore, an animal dies as a result of drinking the same tainted water. 

Furthermore, approximately 80% of land-based pollutants such as chemical, industrial, and agricultural waste wind up in water bodies. 

Furthermore, because these water basins eventually link to the sea, they contaminate the sea's biodiversity indirectly. 

4. Food Reaction

Crops and agricultural produce become poisonous as a result of contaminated soil and water. These crops are laced with chemical components from the start of their lives until harvest when they reach a mass level. Due to this, tainted food has an impact on our health and organs. 

5. Climate Change Impact 

Climate change is also a source of pollution in the environment. It also has an impact on the ecosystem's physical and biological components. 

Ozone depletion, greenhouse gas emissions, and global warming are all examples of environmental pollution. Because these water basins eventually link to the sea, they contaminate the sea's biodiversity indirectly. Furthermore, their consequences may be fatal for future generations. The unpredictably cold and hot climate impacts the earth’s natural system. 

Furthermore, earthquakes, starvation, smog, carbon particles, shallow rain or snow, thunderstorms, volcanic eruptions, and avalanches are all caused by climate change, caused entirely by environmental pollution.

How to Minimise Environmental Pollution? 

To minimise this issue, some preventive measures need to be taken. 

Principle of 3R’s: To save the environment, use the principle of 3 R’s; Reuse, Reduce and Recycle. 

Reuse products again and again. Instead of throwing away things after one use, find a way to use them again.  Reduce the generation of waste products.  

Recycle: Paper, plastics, glass, and electronic items can be processed into new products while using fewer natural resources and lesser energy. 

To prevent and control air pollution, better-designed equipment, and smokeless fuels should be used in homes and industries. More and more trees should be planted to balance the ecosystem and control greenhouse effects. 

Noise pollution can be minimised by better design and proper maintenance of vehicles. Industrial noise can be reduced by soundproofing equipment like generators, etc.  

To control soil pollution, we must stop the usage of plastic. Sewage should be treated properly before using it as fertilizers and as landfills. Encourage organic farming as this process involves the use of biological materials and avoiding synthetic substances to maintain soil fertility and ecological balance. 

Several measures can be adopted to control water pollution. Some of them are water consumption and usage that can be minimized by altering the techniques involved. Water should be reused with treatment. 

The melting icebergs in Antarctica resulted in rising sea levels due to the world's environmental pollution, which had become a serious problem due to global warming, which had become a significant concern. Rising carbon pollution poses a risk for causing natural disasters such as earthquakes, cyclones, and other natural disasters. 

The Hiroshima-Nagasaki and Chernobyl disasters in Russia have irreversibly harmed humanity. Different countries around the world are responding to these calamities in the most effective way possible. 

Different countries around the world are responding to these calamities in the most effective way possible. More public awareness campaigns are being established to educate people about the hazards of pollution and the importance of protecting our environment. Greener lifestyles are becoming more popular; for example, energy-efficient lighting, new climate-friendly autos, and the usage of wind and solar power are just a few examples. 

Governments emphasise the need to plant more trees, minimise the use of plastics, improve natural waste recovery, and reduce pesticide use. This ecological way of living has helped humanity save other creatures from extinction while making the Earth a greener and safer ecology. 

 Conclusion

It is the responsibility of every individual to save our planet from these environmental contamination agents. If preventive measures are not taken then our future generation will have to face major repercussions. The government is also taking steps to create public awareness. Every individual should be involved in helping to reduce and control pollution.

FAQs on Environmental Pollution Essay

1. What do you understand by ‘Environmental Pollution’?  

Environmental pollution is the contamination of the environment and surroundings like air, water, soil by the discharge of harmful substances.

2. What preventive measures should be taken to save our environment?

Some of the preventive measures that should be taken to save our environment are discussed below. 

We can save our environment by adopting the concept of carpooling and promoting public transport to save fuel. Smoking bars are public policies, including criminal laws and occupational safety and health regulations that prohibit tobacco smoking in workplaces and other public places.  

The use of Fossil fuels should be restricted because it causes major environmental issues like global warming.  

Encourage organic farming to maintain the fertility of the soil.

3.  What are the main sources of soil pollution?

The main sources of soil pollution as follows:

Industrial waste

Urban commercial and domestic waste

Chemical fertilizers

Biomedical waste

4. What is organic farming?

 It is a farming method that involves growing and nurturing crops without the use of synthetic fertilizers and pesticides.

Essay on Environmental Pollution In 100 to 150 Words For Students

Pollution is a very important issue in today’s society and is often discussed, such as the environment and climate change. While there have been many different solutions suggested to combat the problem, they are not always going to be practical or sustainable. In this essay, I discuss some of these solutions, what works and what doesn’t work.

Table of Contents

Environmental Pollution Essay For Students

Environmental pollution is an urgent and concerning issue that casts a dark shadow over the well-being of our planet and all life forms inhabiting it. Environmental pollution is the act of introducing harmful substances and pollutants into the environment., leading to adverse effects on nature and human health. This global problem comes in various forms,There are various types of pollution such as air pollution, water pollution, soil contamination, and noise pollution. Each type has its own causes and can have significant consequences.

Air pollution is one of the most prevalent and alarming types of environmental pollution. It occurs when harmful particles and gases are released into the air from various human activities, including industrial processes, transportation, and burning of fossil fuels. These pollutants can have severe repercussions on human health, causing respiratory problems, cardiovascular diseases, and even premature death. Moreover, air pollution disrupts the balance of nature, affecting wildlife and contributing to climate change and global warming.

Water pollution is another significant concern that poses a severe threat to aquatic life and human populations alike. It arises when harmful substances, such as industrial waste, chemicals, and untreated sewage, find their way into water bodies. This contamination leads to the destruction of marine ecosystems, loss of biodiversity, and the spread of waterborne diseases. Access to clean and safe drinking water becomes scarce, affecting millions of people worldwide and exacerbating social and economic disparities.

Soil contamination is equally worrisome, with detrimental effects on agriculture, human health, and ecosystems. Improper waste disposal, excessive use of pesticides, and industrial activities contribute to soil pollution. Contaminated soil can lead to the accumulation of toxic substances in crops, posing health risks for those consuming them. Furthermore, soil pollution disrupts the natural balance of the environment, threatening the survival of plant and animal species that rely on healthy soil for sustenance.

Noise pollution, though often overlooked, has a significant impact on human well-being and wildlife. It results from excessive noise generated by transportation, construction, industrial facilities, and urbanization. Being exposed to noise pollution for a long time can cause stress, difficulty sleeping, and even hearing loss in humans. Animals, especially those in urban environments, suffer from altered behavior and communication patterns, affecting their survival and reproductive success.

The consequences of environmental pollution are profound and multi-faceted, posing challenges on a global scale. Rising temperatures due to greenhouse gas emissions have led to climate change, with melting ice caps and disruptions in weather patterns. This has severe implications for our planet, including rising sea levels, extreme weather events, and threats to vulnerable ecosystems and species.

To address environmental pollution and mitigate its impact, concerted efforts are required at all levels of society. Governments must enact and enforce stringent regulations to control emissions, promote cleaner technologies, and encourage sustainable practices. Industries need to adopt cleaner production methods and invest in environmentally friendly technologies. Individuals can contribute by adopting eco-friendly habits, such as reducing waste, conserving energy, and using public transportation or carpooling.

Education and awareness play a pivotal role in combating environmental pollution. By fostering a sense of responsibility and environmental consciousness, we can instigate positive change in our communities. Environmental education in schools and awareness campaigns can empower individuals to make informed choices and embrace a sustainable lifestyle.

In conclusion,

Environmental pollution is a grave and urgent challenge that threatens the health and stability of our planet. Its diverse forms, from air and water pollution to soil contamination and noise pollution, have far-reaching consequences for both nature and human populations. To safeguard our future and that of future generations, we must act collectively and decisively to reduce pollution, adopt sustainable practices, and protect the delicate balance of our environment. Only through a united and dedicated effort can we secure a cleaner, healthier, and more sustainable world for generations to come.

Hello! Welcome to my Blog StudyParagraphs.co. My name is Angelina. I am a college professor. I love reading writing for kids students. This blog is full with valuable knowledge for all class students. Thank you for reading my articles.

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Home — Essay Samples — Environment — Pollution — The Rise of Environmental Pollution and Its Harmful Effects

The Rise of Environmental Pollution and Its Harmful Effects

• Categories: Pollution

About this sample

Words: 506 |

Published: Jul 17, 2018

Words: 506 | Page: 1 | 3 min read

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Paragraph on Pollution in English [100, 150, 200, 250 Words]

Paragraph Writing on Pollution in English: Pollution has become a big environmental problem today. In this article, you are going to learn how to write a paragraph on pollution in English (100, 150, 200 and 250 Words). We’ve included both short and long paragraphs about pollution. These paragraphs will be helpful for the students of all classes (class 5 to class 12). So, let’s begin.

Table of Contents

Short Paragraph on Pollution: 100 Words

Pollution has become a big problem these days. Because of rapid industrialization and urbanization, the environment which includes air, water, and soil has been polluted. Due to deforestation and industrialization, air is being highly polluted, and this leads to global warming. All the water sources are highly polluted today. The excessive use of pesticides and fertilizers has polluted the soil badly. The use of firecrackers, loudspeakers, etc. affects our hearing ability.

Pollution has a severe impact on our health. It causes headache, bronchitis, heart problems, lung cancer, cholera, typhoid, deafness, etc. Due to pollution, the balance of nature is being disturbed. We have to address this issue with earnestness and seriousness.

Pollution Paragraph in English: 150 Words

The environment is being highly polluted today. Pollution is broadly of four types – air pollution, water pollution, soil pollution and noise pollution. All kinds of pollution are the results of rapid industrialization and urbanization.

The poisonous gases such as carbon dioxide, carbon monoxide, CFC, Sulfur dioxide etc. released from motor vehicles, burning of fossil fuels, factories, power plants cause air pollution. The ozone layer is getting affected badly by air pollution. Air pollution can damage our lungs and respiratory system. Sewage from domestic households, industries, factories contaminates the water greatly. This leads to chronic diseases like cholera, typhoid and diarrhea. Due to the use of chemical fertilizers and pesticides the soil is being contaminated badly.

The sound of loudspeakers, aircraft, firecrackers, horns of motor vehicles cause noise pollution . Continuous exposure to a high level of noise can cause cardiovascular diseases and can even cause permanent hearing loss.  Pollution is constantly damaging our biological system. We should come forward to put an end to pollution to enjoy a happy and better life.

Also Read: Environmental Pollution Paragraph

Paragraph Writing on Pollution: 200 Words

The problem of pollution has become very serious in recent years. There are different forms of pollution in the atmosphere. Water pollution, air pollution, soil pollution and noise pollution are the most common among them. Actually, the main reason of pollution lies in our habits. We are cutting down trees, making big buildings and industries.

We are throwing Industrial waste & chemicals, domestic waste, sewage and garbage in the rivers and streams. This causes water pollution. The burning of fossil fuels, industrial emissions and gases from motor vehicles produce toxic greenhouse gases in the air. Due to the emission of greenhouse gases like carbon dioxide, CFC, nitrous oxide and methane the average temperature of the earth is rising which leads to Global Warming .

Due to the overuse of fertilizers and insecticides, the dumping of domestic and radioactive waste the soil is getting polluted. Loudspeakers and pressure horns create sound pollution. They make us deaf.

Due to pollution, we are going through harmful diseases such as Pneumonia, Asthama, Bronchitis, Lung cancer, Skin cancer, heart disease, etc. If we want to live a healthy life, we must change our living style. We cannot be healthy in a polluted atmosphere. It is our duty to keep our surrounding pollution free.

Essay on Pollution: 250 Words

Our planet faces today a hard thing to solve. It is pollution in air, land and water. It has now become a great problem that our life is threatened. Air is the most polluted of all. In our city-life, we have little open space where we can have fresh air, where our children can play without inhaling smoke and dust and where our old elders can spare to stand and stare and breathe to the full.

In cities, factories give out smoke, and motor cars and other vehicles emit gases. Besides, people in both urban and rural areas use loudspeakers. Different vehicles use air horns. The high sounds by all these things deafen our ears. For the expansion of Industry, greenery is mercilessly destroyed.

The land is also polluted chiefly as a result of garbage heaped and rotten for days together, plastic packets thrown everywhere and the dirty sweepings left about in the lanes. Dustbins are never used properly. The drains gush out untreated water into rivers and seas. The wastes from the factories are poured into rivers. Tankers are washed on high seas.

All these are the main factors for water pollution. The only remedy is the public awareness. We ought to be aware that the green stretch should not be perished. We should not throw any dirty things here and there. Let us live and let Nature live.

Word Meanings:

• Mercilessly – showing no kindness
• Gush out – to rush or flow out of something in large amounts
• Threatened – in danger
• Perish – to die or be killed

Frequently Asked Questions (FAQs) on Pollution:

Pollution is one of the major concerns in our modern world. Pollution means contamination of the environment due to harmful substances that can cause damage to living organisms. There are many types of pollution including air pollution, water pollution, noise pollution and land pollution. The main sources of pollution are industries, vehicles, construction sites and power plants.

Pollution can cause many severe health effects like Pneumonia, Bronchitis, respiratory diseases, cardiovascular diseases, lung cancer, diarrhea, hearing loss, high blood pressure, etc.

Through our joint efforts we can prevent pollution. Air pollution can be reduced by using environment-friendly vehicles, planting more trees and using alternate sources of energy. Water pollution can be prevented by reducing plastic consumption, by using natural methods to treat sewage. Noise pollution can be prevented by reducing the source of knowledge, using less horns.

The major pollutants available in the environment are carbon monoxide, nitrogen oxides, lead, ozone, sulfur oxides, etc.

Related: Paragraph on Importance of Trees

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5 thoughts on “paragraph on pollution in english [100, 150, 200, 250 words]”.

Very nice my brother. Thank you

Your writing style is engaging, and the information is presented clearly. Thanks for this informative piece!

Pollution is a big problem in the world. It’s caused by a lot of things, like cars, factories, and power plants. It’s also caused by people. They can pollute the air, water, and land by

It is a very good paragraph

Pollution has become a big problem these days. Such as headache, heart problem, lung cancer, cholera, typhoid, and even deafness.

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Smog over Shanghai in 2018. Over the last decade, China has sharply cut air pollution. Johannes Eisele / AFP via Getty Images

Pollution Paradox: How Cleaning Up Smog Drives Ocean Warming

New research indicates that the decline in smog particles from China’s air cleanups caused the recent extreme heat waves in the Pacific. Scientists are grappling with the fact that reducing such pollution, while essential for public health, is also heating the atmosphere.

By Fred Pearce • May 28, 2024

They call it “The Blob.” A vast expanse of ocean stretching from Alaska to California periodically warms by up to 4 degrees Celsius (7 degrees F), decimating fish stocks, starving seabirds, creating blooms of toxic algae, preventing salmon returns to rivers, displacing sea lions, and forcing whales into shipping lanes to find food.

The Blob first formed in 2013 and spread across an area of the northeast Pacific the size of Canada. It lasted for three years and keeps coming back — most recently last summer . Until now, scientists have been unable to explain this abrupt ocean heating. Climate change, even combined with natural cycles such as El Niño, is not enough.

But new analysis suggests an unexpected cause. Xiaotong Zheng, a meteorologist at the Ocean University of China, and international colleagues argue that this extraordinary heating is the result of a dramatic cleanup of Chinese air pollution. The decline in smog particles, which shield the planet from the sun’s rays, has accelerated warming and set off a chain of atmospheric events across the Pacific that have, in effect, cooked the ocean.

Other researchers spoken to by Yale Environment 360 see the finding, made with the help of in-depth climate modeling, as having potentially critical implications for future climate in the Pacific and elsewhere. Emissions of the tiny particles that cause smogs, collectively known as aerosols, are in decline across most of the world — apart from South Asia and Africa. Scientists are concerned that the cleanups will both heat the global atmosphere and lead to more intense regional ocean heat waves.

The idea that cleaning up air pollution can worsen atmospheric warming sounds counterintuitive.

Yangyang Xu, an atmospheric scientist at Texas A&M University not involved in the study, said it shows that “aerosol reductions will perturb the climate system in ways we have not experienced before. It will give us surprises.”

Indeed, that may already be happening in the Atlantic. Some researchers we spoke to argue that the exceptional heat wave that spread across the North Atlantic from spring last year until April this year, sending fish fleeing for cooler Arctic waters, may have owed its intensity to international efforts to reduce aerosol emissions from ships crossing the ocean.

The idea that cleaning up air pollution can worsen atmospheric warming sounds counterintuitive. But small particles suspended in the atmosphere, collectively known as aerosols, are very different from greenhouse gases. Instead of warming the planet by trapping solar radiation, they shade it by scattering incoming sunlight and sometimes creating clouds.

They don’t stick around in the air for more than a few days. But climate modelers calculate that while they are there, they fend off as much as a third of greenhouse warming.

The Blob, a long-lasting marine heat wave, off the Pacific coast of North America, shown here in August 2019. NASA

In recent years, however, this cooling influence has begun to decline in much of the world. Thanks to clean-air legislation intended to protect public health, aerosol emissions have been reduced in Europe and North America since the 1980s. And over the past decade, the same has happened in China, where tough government controls on dirty industries, introduced by President Xi Jinping in 2013, have cut overall aerosol emissions by 70 percent, according to Zheng.

Globally, there are now fewer anthropogenic aerosols in the air at any one time than for decades. Susanne Bauer, a climate modeler at the NASA Goddard Institute for Space Studies, says this “turning point of the aerosol era” occurred in the first decade of this century, and seems set to continue, as more countries seek to banish smogs.

As a result, scientists say, the aerosol mask is slipping, causing a boost to global warming in many regions. “We are currently experiencing greenhouse-gas driven global warming enhanced by aerosol removal,” says Ben Booth, a climate modeler at the U.K. Met Office.

The climatic repercussions of this are not unexpected. Predicted declines in aerosol cooling are already factored into projections of future global warming by the Intergovernmental Panel on Climate Change (IPCC). But Zheng’s new findings on the cause of the warm Pacific blob suggest that we can also expect more and bigger regional climatic surprises.

Without aerosols’ cooling effect, the world would already have reached the temperature threshold of dangerous climate change.

Why so? The answer lies in the fact that aerosols do not remain aloft for long enough in the air to mix thoroughly in the atmosphere. So national pollution cleanups will create radically new maps of aerosol distribution.

Some areas will heat much more than others, and this differential warming has the potential to destabilise atmospheric circulation patterns, which are largely heat-driven. This is what appears to have been happening in the northeast Pacific, says Zheng.

When he and Hai Wang, also of the Ocean University of China, along with colleagues in the United States and Germany, modeled the likely impacts on circulation systems of the recent cleaning of the air over eastern China, they found that clearing the country’s smogs caused exceptional atmospheric heating downwind over the Pacific.

This altered air pressures and intensified the Aleutian Low, a semi-permanent area of low pressure in the Bering Sea. This in turn reduced wind speeds further east, limiting the ability of the winds to cool the ocean below, providing “a favorable condition for extreme ocean warming.”

Zheng and colleagues warn that the findings are a harbinger of future “disproportionately large” warm-blob events.

Smog shrouds the Taj Mahal in Agra, India, last November. Pawan Sharma / AFP via Getty Images

Aerosols come in many shapes and sizes, from dust and soot to tiny particles invisible to the eye. They have many natural sources, such as forest fires and dust storms. But since the Industrial Revolution the aerosol load in the atmosphere has been dramatically increased by anthropogenic sources, primarily the burning of fossil fuels such as coal and oil.

These emissions include large volumes of sulfur dioxide (SO2), a gas that reacts readily with other compounds in the air to create tiny particles that both shade the planet and can act as condensation nuclei that cause atmospheric moisture to coalesce into water droplets that form clouds.

Burning fossil fuels produces both planet-warming carbon dioxide and aerosols that mask much of the warming. Atmospheric temperatures depend on the balance between the two. The last IPCC assessment of climate science, published in 2021, calculated that greenhouse gases were producing a warming effect of around 1.5 degrees C, with 0.4 degrees of this masked by aerosols.

“Without the cooling effect of the aerosols, the world would already have reached the 1.5- degree temperature threshold of ‘dangerous’ climate change as set out by the Paris agreement,” says Johannes Quaas, a meteorologist at the University of Leipzig and former IPCC lead author.

But the balance is shifting as ever more countries act to reduce aerosol emissions.

Until recently, ships’ aerosol emissions probably cooled the planet more than their greenhouse-gas emissions warmed it.

They do so because of a growing awareness of the public health impacts of aerosols, which the World Health Organization calculates cause more than 4 million premature deaths from cancers and respiratory and cardiovascular diseases each year. Air pollution reduced life expectancy in parts of China by up to five years, according to a 2013 study .

Countries are requiring power companies, industries, and vehicle manufacturers to filter particulates and either burn low-sulfur fuel or fit equipment to strip SO2 from stack emissions — thus cleaning up aerosol and SO2 emissions without reducing the energy produced by burning the fuel.

Europe and North America have had clean air laws in place for almost half a century. Since 2013 — following a run of debilitating smogs in many cities — China has followed, at break-neck speed. Its anthropogenic aerosol emissions have fallen by 70 percent in a decade, and SO2 emissions have been reduced even more, from 20.4 million tons in 2013 to 2.4 million tons in 2022.

Chinese researchers have tracked the impact of this on local climate in some detail. Yang Yang, an atmospheric physicist at Nanjing University of Information Science and Technology, calculates that by 2017, it had boosted the existing greenhouse warming trend in eastern China by 0.1 degrees C. As the cleanup extends, including to transportation, he expects this extra heating to increase to between 0.2 and 0.5 degrees C by 2030, and to more than 0.5 degrees C by 2060.

Yang predicts it will also trigger changes in local atmospheric circulation that will result in more rainfall over southern China and beyond, in nearby countries such as the Philippines. Zheng’s new research suggests that the effects are already far more long-ranging, stretching across the Pacific to create The Blob on the shores of the U.S.

Where else can we expect disrupting local climate change? Outside of China, researchers are exploring the potential for oceanic climate surprises arising from recent efforts to cut SO2 emissions from shipping.

Dirty, sulfurous diesel has long been the fuel of choice in ships’ boilers. As a result, the world’s shipping fleets until recently emitted more than 10 million tons of SO2 annually, contributing between 10 and 20 percent of the total anthropogenic climate “forcing” from aerosols, says Michael Diamond, who studies aerosols and climate at Florida State University.

Ships are a major cause of aerosol buildup over oceans, where there are usually few other anthropogenic sources. Satellite images show clear tracks of clouds stretching along major shipping routes.

Burning ships’ fuel also emits carbon dioxide, of course. But until recently, ships’ aerosol emissions have probably cooled the planet more than their greenhouse-gas emissions have warmed it. That is changing, however. Ships seem set to turn from planetary coolers to planetary warmers.

Eliminating methane, a short-lived greenhouse gas, can provide a quick fix for some of the impacts of lost aerosols.

In 2020, the U.N.’s International Maritime Organization (IMO) responded to rising pressure to clear the air around ports by reducing the sulfur content allowed in shipping fuel from 3.5 percent to 0.5 percent. Reduced ships’ SO2 emissions have already resulted in fewer clouds over shipping lanes and and higher ocean temperatures.

Diamond says he has a paper currently under peer review whose “takeaway is that something like a third of the North Atlantic marine heat wave [of the past year] might be attributable to the IMO regulations.” Booth, meanwhile, is coauthor of a paper preprinted online this month which argues that shipping emissions reductions “may help explain part of the rapid jump in global temperatures over the last 12 months.”

Where are we headed?

If the world works successfully toward lowering greenhouse gas emissions in the coming decades, while also continuing to curb aerosols, then we can still expect continued warming for which aerosol reductions are a growing cause.

A satellite view of aerosol trails left by ships crossing the North Pacific. NASA

Yang recently coauthored a paper that forecasts a mid-century world in which the warming impact of the clearer air will “far outweigh those of greenhouse gases.” There will be “increased humid heat waves with longer duration and stronger amplitudes,” he says.

So what can be done? Can the world have clean air while also keeping warming to bearable levels and avoiding worsening ocean heat waves?

Most scientists spoken to for this article agreed that the best route remains doubling down on reducing greenhouse gas emissions. But Diamond suggests the aerosol dilemma shines a spotlight on the need to give priority to cutting methane emissions .

This virulent greenhouse gas is second to carbon dioxide in importance as a planetary warmer. Right now, notes Diamond, its warming effect is almost identical to the average cooling effect of continued aerosol emissions. And because methane is a relatively short-lived greenhouse gas, persisting in the atmosphere for only around a decade, its elimination can provide a quick fix for some of the impacts of the lost aerosols. Luckily, there is low-hanging fruit to achieve this: The easiest and cheapest actions include preventing the venting of methane from gas and oil wells and pipelines.

To be clear, nobody — but nobody — suggests that we should stop the cleanup of aerosols. The death toll would just be too great.

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Paragraph on Pollution

Pollution refers to the presence or introduction of harmful or toxic substances into the environment. In this case environment refers to all natural living and non living things those surround us. Forests, water bodies, air, oceans all constitute our natural environment and, any foreign substance that compromises their purity and longevity is termed as “Pollution”.

As per the recent 2018 EPI (Environmental Performance Index) statistics, India ranks 177 out of 180 countries in terms of air quality and overall environmental health; that’s a steep fall from 141 st rank in 2016.

India is followed by the Democratic Republic of Congo on 178 th rank, Bangladesh on 179 th and Burundi on 180 th . Top five nations with the best EPI index are Switzerland, France, Denmark, Malta and Sweden respectively.

Long and Short Paragraphs on Pollution in English

Below we have provided both long and short paragraphs on pollution of varying word lengths. These paragraphs will provide you in depth knowledge of the issues regarding environmental pollution. After going through them you will be able to define pollution and its types, state their causes, effects, solution and also means to prevent them. You can also select a paragraph of your choice, for a speech, competition or debate as per your requirement.

Paragraph on Pollution 1 (100 Words)

Environmental pollution refers to the presence of harmful and poisonous substances into our environment. It is not only limited to air pollution but can also affect water bodies, soil, forests, aquatic life and all the land living species as well. The main factors leading to environmental pollution are human generated.

Since ages we have been interfering with the environment in order to expand our habitat and to make living easy. Humans have invented automobiles, set up factories, cut down forests to make way for roads and cities – all compromising the environmental health. Inadequate waste disposal and its littering have resulted in polluting our oceans and water bodies, rendering them useless and threatening the life of the species which depend on them.

Paragraph on Pollution 2 (150 Words)

Pollution has tremendous adverse affects on environment, resulting in its degradation and also in depletion of living species. It has severe aftereffects like acid rain, global warming, famine, draught and extreme climatic conditions along with other consequences. The most common type of pollution is air pollution. The air we breathe today in metropolis or cities is choked with toxic CO (Carbon Monoxide, CO 2 (Carbon di- oxide), N 2 O (Nitrous Oxide) and CH 4 (Methane). Inhalation of these gases not only leads to respiratory ailments in humans but also CO 2 is a potent green house gas leading to escalated green house effect and global warming.

Transportation industry causes 25% of the global green house gas emission; subsequently, resulting in green house effect and a raised earth’s average surface temperature. Earth’s average surface temperature is constantly rising and is estimated to rise by around 1.8 by the end of present century. Even the temperature of oceans is on rise, though at a slower rate owing to the ocean’s larger heat absorbing capacity.

Paragraph on Pollution 3 (200 Words)

Though air pollution is the most common type of pollution evident today, it is not the only one. Besides air pollution, there are a number of human induced activities those pollute or natural resources like water bodies and soil. Inadvertent industrialization has led to air as well as water pollution, having adverse affects on environmental health. Industries require a good amount of water to operate and so are mainly set up in proximity to a naturally occurring stream, river or water body.

Also, the industrial waste which includes toxic chemicals like asbestos etc is carried away into our water bodies by using fresh water. It not only pollutes our natural water resources but also renders them harmful to use and results in decline of species, plants and algae.

Another most common factor threatening the health of water resources and soil is – littering. Inadequate mechanism of waste disposal and ignorance results in littering at various places. The most common type of pollutant through littering is plastic. Thin plastic bags of varied dimensions, when not disposed properly; get into our water bodies and soil. Being non degradable they stay there for centuries, polluting them and threatening lives. Species like turtles and fishes are known to have eaten plastic and died.

Paragraph on Pollution 4 (250 Words)

Pollution is the most immediate threat to our environment and is a global concern. It affects the air, water bodies, forests, vegetation, soil, oceans and other natural resources, having long lasting and fatal consequences. Every major pollutant which threatens the environment is produced by human activities. In their desire to progress and expand their boundaries, humans have done considerable damage to the environment.

Natural resources have not only been used incessantly but also polluted, without considering the after affects. We just don’t realize the fact that the natural resources that we pollute today have taken Millions of years to be produced.

Today human induced pollution has become so vast that no corner of the world is isolated from its affects. People are suffering from respiratory diseases, given to the toxic fumes emitted out of factories and automobiles. Places across the globe are witnessing extreme hot and cold climatic conditions as result of global warming. Famine and droughts have become common with depleting natural water resources.

Galactic and polar ice is melting as a result of global warming, consequently resulting in raised ocean level and floods. Also, the rise in oceanic temperature and plastic pollution results in depletion of marine species like – planktons, coral fish, seals, great barrier reef etc.

Deforestation too results in raised air pollution level as forest act as natural air filters – cleaning the air by absorbing harmful gases and emitting oxygen. They act as natural air filters, without them earth would be like nothing else than a large ball of smoke. Unless we realize the severity of the damage that we have done and take preventing measures on war footing; our future generations will live in poor health and despair.

Paragraph on Pollution 5 (300 Words)

The term pollution refers to the introduction of a harmful substance into the environment and the harmful substance is called the pollutant. There are various causes of pollution and almost all of them are human induced.

Causes and Effects of Pollution

There are numerous human activities those cause pollution. Most prominent of the activities causing environmental pollution are fossil fuel consumption, industrialization and littering. As per global estimates, fossil fuels account for 80% of world’s energy annually. Also, the burning of fossil fuel produces 21.3 Billion Tonnes of CO 2 every year, which is a potent green house gas. Presence of large amount of CO 2 in the environment results in an increased green house effect and hence global warming.

Industries are usually set up in proximity of a water body and use fresh water to wash out industrial waste into the water bodies. Industrial waste may include many harmful substances like gravel, sand, toxic chemicals and metals etc; which are washed into water bodies polluting them. Often the sewage of cities is discharged into rivers and streams, which too results in their pollution and deplete the marine life.

Littering is also responsible for a good amount of environmental pollution and ecological imbalance. Inefficient waste collection and disposal has resulted in large heaps of plastic and toxic wastes in and around the cities. This non bio degradable waste gets into our water bodies, polluting them and threatening marine life.

Strict environmental policies and larger public awareness are the keys to preventing further environmental damage. Policies mandating the industries to take necessary steps towards reducing their carbon footprint are a must. Moreover, any violation should be dealt with strictly imposing hefty fines and shut down. Efficient waste collection and disposal mechanism is also required to reduce prevent harmful waste from reaching our water bodies and soil.

Paragraph on Pollution 6 (350 Words)

Today pollution has become a global threat and also an immediate one, threatening the environment and ecological balance.

Types of Pollution and Causes

Below we will go through various types of pollution and its causes. Pollution could be broadly classified into the following categories –

Air Pollution

Air Pollution refers to the presence of harmful and poisonous gases present in the environment. Fossil fuel consumption emanating toxic gases like Carbon monoxide, Carbon dioxide etc is the prime factor contributing to air pollution.

Noise Pollution

Noise pollution also called sound pollution refers to the presence of unwanted sound in the environment which has harmful effects on the activities of humans and animals. Some of the prime contributors of noise pollution are transportation vehicles, construction works, loud music etc.

Soil Pollution

Soil pollution is caused by the introduction of human made chemicals and pollutants into the soil, making it toxic and reducing yield. The main causes of soil pollution are use of pesticides by agriculture industry, industrial waste disposal, littering and improper waste disposal.

Light Pollution

Light Pollution is also called photo pollution and refers to the presence of human made light in the environment during night. The main cause of light pollution is excessive and non essential lighting. Light pollution disrupts with the environment and reduces its beauty. Some bird species are known to get confused by excessive lighting.

Thermal Pollution

Thermal Pollution refers to a sudden change in ambient water temperature. One of the prime causes of thermal pollution is the use of water as coolant by power plants and industries. The water used as coolant gets warm and when it is returned to natural environment, it results in sudden temperature changes, decreasing oxygen content and affecting ecosystem.

Water Pollution

Water pollution refers to the contamination of water bodies by human activities. Prime causes leading to water pollution are industrial waste disposal, sewage disposal and littering. Industrial waste containing harmful and toxic chemicals is poured into water bodies, resulting in their pollution. Also, littering in and around water bodies results in their pollution and makes the water hazardous to use.

Radioactive Pollution

Radioactive Pollution refers to the presence of radioactive substances in the environment. Such radioactive substances have hazardous effects on human health and environment. The factors leading to radioactive pollution are inefficient nuclear waste handling, nuclear explosion and nuclear accidents.

Paragraph on Pollution 7 (400 Words)

Pollution refers to the introduction of toxic substances into the environment. Majority of pollutants are produced by human activities; though, some of the natural causes are also responsible for environmental pollution.

Natural Causes of Pollution

Natural air and water pollution is caused by natural events, either temporary or continuous. The pollution brought by the natural causes is negligible as compared to human generated causes. Some natural causes of air pollution are volcanic eruptions and fog. Some isolated areas may have the seepage of some toxic gases like Radon or CO 2 etc leading to air pollution.

Natural water pollution is mainly caused due to surface run off, having insoluble and impure substances and also from the soil in proximity having naturally occurring toxic substances.

Effects of Pollution on Human Beings

Pollution is a serious threat concerning the health of not only humans but also of plants, birds, animals and marine species. Studies reveal that pollution considerably reduces the life expectancy of an individual. 90% of people worldwide are breathing polluted air and pollution claims Millions of lives globally. In India alone, an estimated 7 lakh people die every year due to various pollution generated ailments. Not to mention the famine and draughts as results of pollution; subsequently, resulting in large migrations of humans and animals.

What if Pollution Goes Unchecked

If pollution continued at the same rate as of today, the day is not far, when the sky will become foggier and breathing difficult due to scarcity of oxygen. Incessant water pollution will lead to water scarcity, famine, drought and ecological imbalance. All the living species and resources will gradually perish leaving earth as a barren and lifeless ball of mud and smoke.

Best Ways to Control Pollution

Some of the best ways of controlling pollution are – making eco friendly transportation choice, efficient waste collection and disposal, non use of plastic products, controlled human population, forest plantation and a global policy governing the establishment of industries and regulating their carbon foot print. Most important of it all – the awareness of general public needs to be raised on issue concerning pollution.

People should acknowledge the fact that, finding a solution to pollution and saving life of the planet and its entire living species, ultimately rests with humans. Also, it would be a mistake not to work on it together. Pollution at one place threatens the life at some distant place; therefore, pollution should be dealt with globally, together.

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A hidden threat

Fast-rising seas could swamp septic systems in parts of the south.

On the worst days, when the backyard would flood and the toilet would gurgle and the smell of sewage hung thick in the air, Monica Arenas would flee to her mother-in-law’s home to use the bathroom or wash laundry.

“It was a nightmare,” Arenas, 41, recalled one evening in the modest house she shares with her husband and teenage daughter several miles north of downtown Miami.

She worried about what pathogens might lurk in the tainted waters, what it might cost to fix the persistent problems and whether the ever-present anxiety would ever subside.

Residents in neighborhoods around Arenas’s have similar tales to share — of out-of-commission toilets, of groundwater rising through cracks in their garage floors, of worries about their own waste running through the streets and ultimately polluting nearby Biscayne Bay.

For all the obvious challenges facing South Florida as sea levels surge, one serious threat to public health and the environment remains largely out of sight, but everywhere:

Septic tanks.

Millions of them dot the American South, a region grappling with some of the planet’s fastest-rising seas, according to a Washington Post analysis . At more than a dozen tide gauges from Texas to North Carolina, sea levels have risen at least 6 inches since 2010 — a change similar to what occurred over the previous five decades.

One village’s risk

Officials worry about the threat of rising groundwater along the Little River in and around El Portal, where many homes rely on septic systems

Septic systems

Elevation above king tide*

Profile along NW Second Avenue

Above king tide

Below king tide

Little River

Officials worry about the threat of rising

groundwater along the Little River in and

around El Portal, where many homes rely

on septic systems

Unincorporated

Miami Shores

To Biscayne

King tide shown is the highest observed tide at Virginia Key on Oct. 28, 2023 (1.96 ft.)

Source: Miami-Dade County

Northwest 2nd AVe

BISCAYNE BAY

Along those coastlines, swelling seas are driving water tables higher and creating worries in places where septic systems abound, but where officials often lack reliable data about their location or how many might already be compromised.

“These are ticking time bombs under the ground that, when they fail, will pollute,” said Andrew Wunderley, executive director of the nonprofit Charleston Waterkeeper, which monitors water quality in the Lowcountry of South Carolina.

To work properly, septic systems need to sit above an adequate amount of dry soil that can filter contaminants from wastewater before it reaches local waterways and underground drinking water sources. But in many communities, that buffer is vanishing.

How rising waters threaten

septic systems

The most common type of septic systems rely on gravity to move sewage through a tank where solids settle and liquid waste is slowly released into the soil through a series of perforated pipes called a drain field.

Normal operation

DRAIN FIELD

Sewage enters

Wastewater filters

through soil

GROUNDWATER

The soil acts as a natural filter, neutralizing germs and pollutants before they can contaminate groundwater.

Rising water table

Contamination

Sea level rise and extreme rainfall are raising groundwater levels, resulting in more shallow buffers of soil that help protect local waterways and underground aquifers.

System failure

If a conventional septic system becomes submerged, wastewater will not be properly treated. Toilets can stop working and sewage can flood yards.

The most common type of septic systems rely on gravity to move sewage through a tank where solids settle and liquid waste is slowly released into the soil through a series of perforated pipes called a drainfield.

How rising waters threaten septic systems

An estimated 120,000 septic systems remain in Miami-Dade County, their subterranean concrete boxes and drain fields a relic of the area’s feverish growth generations ago. Of those, the county estimated in 2018, about half are at risk of being “periodically compromised” during severe storms or particularly wet years.

Miami, where seas have risen six inches since 2010, offers a high-profile example of a predicament that parts of the southeast Atlantic and Gulf coasts are confronting — and one scientists say will become only more pervasive — as waters continue to rise.

Virginia Key, Biscayne Bay, Fla.

sea level rise since 2010

0.4 inches per year

0.1 inches per year

Annual mean

Here, expensive repairs afflict homeowners as septic systems falter. Fetid water increases the risk of gastrointestinal diseases and other health hazards as floodwaters fill yards and streets. Profound worries persist about the environmental toll — which, researchers in Miami say, means submerged septic tanks are leaking nutrients into the porous limestone, potentially fueling algae blooms that kill fish .

“It’s really pretty gross,” said Michael Sukop, a hydrogeologist at Florida International University.

Rising seas will only exacerbate the problem, he added. “As the water table gets higher, all bets are off.”

Miami-Dade County is racing to replace as many septic tanks as possible, as quickly as possible. But it is a tedious, expensive and daunting task, one that officials say will ultimately cost billions of dollars they don’t yet have.

It also is far beyond a Florida problem.

In Georgia, officials have documented more than 55,000 septic tanks in counties near the Atlantic Coast in an ongoing data gathering effort. In North Carolina, researchers estimate, the discharge from approximately 1 million septic systems drains to waterways that eventually reach the ocean. In South Carolina, the issue has been the subject of legal fights and proposals in the state legislature.

In numerous states, researchers are studying the potential effects of what they call a largely unseen and unquantified environmental and public health threat.

“We don’t even know the scale of the problem,” said Rob Young, director of the Program for the Study of Developed Shorelines at Western Carolina University. “I think it’s everywhere. And it can’t get better as long as sea levels are rising. The only question is how quickly it can get worse.”

An environmental mess

More than 700 miles north of Miami, Mike O’Driscoll is among the scientists trying to decipher just how quickly rising seas are driving water tables higher, and why that matters.

O’Driscoll, a coastal studies professor at East Carolina University, and several colleagues have spent recent years documenting how rising groundwater is altering the hydrology along the Outer Banks in North Carolina.

In Nags Head, the group installed technology to monitor nearly a half-dozen aquifer wells for fluctuations in groundwater levels. They compared their findings to similar data from the North Carolina Department of Environmental Quality stretching back to 1983, and a clear trend emerged: Rising sea levels are raising the groundwater.

“If you look around the Outer Banks, the groundwater has risen one and a half feet in some places,” O’Driscoll said.

North Carolina requires about a foot to a foot and a half of separation between septic drain fields and the seasonal high-water table, depending on the soil type. But in places, that cushion is dwindling.

The Drowning South

“Rising groundwater has started to inundate systems in low-lying areas,” O’Driscoll said. “Some may be failing right now, but within a couple of decades, in some places, it won’t be viable to use conventional septic systems anymore.”

Beyond the environmental concerns, O’Driscoll worries about the financial impact for coastal communities and residents. It can cost homeowners $30,000 or more to install more advanced on-site wastewater treatment systems, and it costs localities many millions to expand existing infrastructure.

The Environmental Protection Agency estimates that roughly 20 percent of households in the United States rely on septic systems to treat their wastewater. That figure rises to more than one-third of homes in the Southeast, according to the agency . Florida is home to an estimated 2.6 million such systems.

In some places, such as rural areas not served by a centralized sewer and not threatened by encroaching groundwater, the approach can work well and be cost effective .

When conventional systems work as designed, solids from a home or business’s waste settle within the septic tank, while liquid waste is discharged into a drain field — usually a set of perforated pipes designed to slowly release effluent into the ground. The soil acts as a natural filter, neutralizing disease-causing pathogens, and reducing nitrogen, phosphorus and other contaminants before it reaches groundwater.

But that process is under increasing strain as seas push higher in the region and torrential rainfalls become more common, a combination that can inundate buffers that once existed.

EPA-funded research in Maryland has shown that many coastal properties with septic systems, which already face significant flood risk, will become far more vulnerable in the coming decades. As more septic systems fail, said Allison Reilly, a University of Maryland civil and environmental engineering professor, the more widespread the consequences will become, disproportionately harming low-income and minority residents.

“Right now it’s an environmental issue,” she said, “but as we warm, we’d expect it to become more of a public health issue.”

‘W e know what’s coming ’

Roy Coley , Miami-Dade County’s top sewer and water official, stood in the backyard of a home on NE 87th Street one afternoon. Nearby, workers had dug a trench as they prepared to connect the house and others nearby to a municipal sewer line.

“You’ve got so many thousands to do, where do you start? You start with one,” he said. “These houses are the low-hanging fruit.”

Over the past several years, leaders in Miami-Dade have aggressively pursued federal and state funding to decommission septic tanks and connect homes to sewage lines. The homes along NE 87th Street, not far from the Little River, just off Biscayne Bay, were converted in part using a grant from the Florida Department of Environmental Protection.

Miami-Dade County said it has so far been awarded about $280 million in grants. About 100 homes have been converted, and workers have put in place the public infrastructure to connect another 775. Coley said the county also is trying various approaches to offset connection costs for homeowners, which average around $15,000.

“We are seeking every way in the world to ease that pain,” he said.

But it remains a herculean task. The county estimates that about 9,000 septic tanks already are vulnerable to compromise or failure under current conditions — a number expected to climb as sea levels rise. Coley said roughly 11,000 septic tanks are on the priority list for removal.

Eradicating septic entirely could cost more than $4 billion, the county estimated in 2020. And the future of the effort, officials said in an email, “is strongly dependent on identifying and securing funding sources.”

But Coley said there has been a key shift over time: buy-in from elected officials and residents.

“I think up until now, there was just a general lack of understanding about how failing septic tanks impacted the environment,” he said. But that’s no longer the case. “When you know better, you do better.”

The problem of leaky and failing septic tanks is hardly a new one in Miami, and the area’s geography and geology have always made them a risky proposition.

The author of a 1949 article in Look Magazine titled “Florida’s Polluted Paradise” detailed the estimated 150,000 septic tanks already around greater Miami, many wedged side-by-side in a region that is “prairie-flat” and hardly above sea level.

Even then, South Florida’s heavy rains often overwhelmed them. “I, myself, have seen septic tanks in numbers back up and overflow into lawns and onto sidewalks in residential areas, owning to the fact that the underlying ground was too burdened with sewage and water to contain any more,” wrote the author, Philip Wylie.

Two decades later, little had changed.

A 1970 report from the Federal Water Quality Administration found that as many as 800,000 people around the county relied on septic tanks, and that many waterways suffered from low oxygen concentrations and startling levels of coliform bacteria, which can signal the presence of fecal waste.

“Septic tanks, widely used in Dade County, are public health hazards,” the report concluded.

The federal government insisted the county develop a master plan to reduce sewage pollution and combat leaking waste from septic tanks.

Using hundreds of million dollars of federal money along with public bonds, the county did build new wastewater treatment plants to ease some of the pollution, but it was not a panacea. Today, there remain neighborhoods that are surrounded by municipal sewer service, but where most homes still rely on septic tanks.

“They were intended to be temporary in Miami, and here we are 50, 70 years later,” said Rachel Silverstein, executive director of Miami Waterkeeper, which has campaigned to end septic pollution.

“There’s water everywhere, and there’s nowhere for it to go,” she said one sunny morning as a high tide sent water sloshing over the bulkheads along Biscayne Bay.

As bad as the problem has been historically, there is one aspect long-ago planners did not factor in: sea-level rise.

“Septic systems were not designed with the assumption that groundwater levels would rise gradually over time,” found a 2018 county report , “and as a result many are not functioning as they were originally designed.”

That report emphasizes how elevated groundwater levels are creating an “immediate” public health risk. “There are also many financial and environmental risks, including contamination of the freshwater aquifer, which is the community’s sole source of potable water,” the study found.

In recent years, Miami-Dade Commissioner Raquel Regalado has led the charge toward trying to phase out failing septic systems in the county.

“I hate them all. I want to get rid of all of them,” the Republican lawmaker said of the old concrete tanks.

She spearheaded a moratorium on any new septic systems on county-owned properties, pushed to ensure that development within a certain distance of sewer lines be required to connect, oversaw rules that require more sophisticated, self-monitoring septic tanks when outdated ones must be replaced and supported trying to offset costs of sewer conversions for homeowners.

“We have to get ahead of this, because we know what’s coming,” Regalado said. “It’s an environmental disaster waiting to happen.”

‘It will keep happening’

The lawsuit came from two South Carolina environmental groups — the Charleston Waterkeeper and the Coastal Conservation League.

Amid a building boom, the groups claim, state regulators have failed to adequately consider the effects of sea-level rise and stronger storms when approving growing numbers of septic tank permits across eight coastal counties.

“[Their] failures place the public’s health at risk and expose our state’s waterways, marshes, beaches, and fisheries to significant, documented harms that can be traced to untreated sewage from malfunctioning, ill-maintained, and/or ill-placed septic systems,” one filing read .

The lawsuit, filed in late 2022, cites existing or planned housing developments in vulnerable areas, including several near the town of Awendaw, about 25 miles northeast of Charleston. There, the suit states, hundreds of homes built close together would rely on septic tanks, all near the Cape Romain National Wildlife Refuge.

“A large percentage of the developed land is actually comprised of septic drain fields,” one filing argues , saying that such a situation risks “significant, irreparable harms” to public health and that of nearby marshes, beaches and fisheries. That includes the possibility of diseases such as hepatitis A and salmonellosis, which can be transmitted through fecal matter, and degradation of water quality, the filing said.

The groups want state officials to give special consideration to the cumulative impact of such clusters of septic permits. Already, they argue, South Carolina has no comprehensive inventory of existing septic tanks and little way for the public to challenge permits before they are approved.

“Sea level rise is happening. It will keep happening,” said Leslie Lenhardt, a senior managing attorney for the South Carolina Environmental Law Project, which is working on the case. “It’s steady, and it’s coming for these developments.”

In legal filings and in an email to The Post, the South Carolina Department of Health and Environmental Control said that it follows current law, which requires the agency “to conduct a coastal zone consistency review of only those wastewater treatment systems and septic tanks that handle more than 1,500 gallons per day or handle other than domestic waste.”

The agency acknowledged that there is no database of all septic tanks in the state, and said there is “no legal authority” that requires public notice about pending septic permits — though anyone can request such information by email.

Data provided by the agency shows it has approved increasing numbers of septic permits in the state’s coastal counties: nearly 16,000 from 2018 through 2023, with the largest numbers in Charleston County.

Beyond the courtroom, other South Carolina officials also are attempting to change the status quo.

“Everyone is very proud of the natural resources around here, but it’s fragile,” said state Rep. Joe Bustos (R), whose district encompasses a coastal swath of Charleston County, an area where seas have risen 7 inches since 2010, according to The Post’s analysis.

Bustos has co-sponsored a bill, unpassed by the legislature, that would ban new septic permits within two miles of the coast.

Wunderley, the Charleston Waterkeeper, supports that legislation and has watched both sea-level rise and the area’s growth accelerate in recent years. “It’s creating this dual pressure that’s really hard to deal with,” he said.

The legal and legislative efforts in South Carolina offer a glimpse at the tensions that states and localities face as they confront the legacy of conventional septic tanks in coastal areas where seas are rising fast.

There are success stories, but none are cheap or fast.

In 1999, with evidence that water quality was deteriorating along parts of the Florida Keys, the state mandated that the island chain eliminate the use of tens of thousands of septic tanks and other outdated waste systems. The cost reached roughly $1 billion as Monroe County built centralized sewage and hooked up thousands of homes and businesses.

“There was a huge change in water quality,” said Coley, who spent a decade working for the Florida Keys Aqueduct Authority.

For years, Georgia has worked to compile one of the most robust databases of where its remaining septic systems are — an effort that at times has involved digging through handwritten permits in dusty county filing cabinets. The result is a detailed list that allows state officials to better understand the risks that exist, both now and as groundwater rises over time.

“There are places where septic systems are clearly unsuitable, and that needs to be factored into future land planning,” said Scott Pippin, an attorney and environmental planner at the University of Georgia’s Carl Vinson Institute of Government.

Skip Stiles, a senior adviser at the Norfolk-based group Wetlands Watch, said septic failures are “like a blinking yellow light” that foreshadow a wider set of problems. As waters rise, he said, it will raise wrenching questions where the problem already is shifting from a nuisance to a persistent hazard.

“It’s forcing that decision that all of us in coastal communities are going to face eventually, but some are already facing now: Do I stay or do I go?”

Buying time

Arenas and her family are among the first homeowners to benefit from Miami-Dade County’s race to replace the most vulnerable systems.

Last year, crews removed their septic tank and hooked their house into a nearby municipal sewer line. Overnight, the nightmare vanished. No more monthly calls to have her underground tank pumped out. No more fretting over toxic water in the yard, or racing to a relative’s house to use the bathroom.

“It is 100 percent changed,” Arenas said.

That remains far from the case everywhere.

Less than a mile away, in the quaint village of El Portal, where peacocks lounge on the steps of the municipal building and Spanish moss hangs from giant oaks, Elizabeth Fata Carpenter spent years worried about water rising underneath the community she loves.

Carpenter and her husband moved to the neighborhood in 2019, and their yard flooded on multiple occasions, undermining the septic system behind their 87-year-old house. Especially after heavy rains, water oozed from the cracks in their garage floor. Their overmatched drain field overflowed into their yard and across the patio. They carried their 70-pound dog to higher ground for walks, and kept boots nearby to wade to their cars.

“We know the floodwater on our property is septic tank water,” Carpenter said one morning last fall outside her home, steps from the Little River. “I know it’s flowing into the river, and not just from my house, but everybody’s homes.”

Earlier this spring, the couple sold the house and moved to Fort Lauderdale. But Carpenter remains as chair on El Portal’s sustainability and resilience task force . And as an environmental attorney, she continues to fret about the collective pollution caused by septic tanks.

El Portal Mayor Omarr Nickerson shares those worries, and is working to end his community’s reliance on septic systems. But there is an inescapable obstacle: money.

Nickerson estimates that it would take roughly $50 million to convert the homes of El Portal to the municipal sewer system. The village’s annual budget is about $2 million, he said, more than half of which goes to the police department.

The county has designated roughly $6 million to help kick-start the effort, Nickerson said, but El Portal also must compete for funding with dozens of other local governments.

He worries that the issue, if left unsolved, might not only pollute the bay, but eventually drive people from his community.

Walking the streets on a postcard-perfect morning, Nickerson points to houses where unseen troubles lie. Where toilets back up. Where sewage-tainted water sometimes swamps yards and driveways. Where homeowners keep sandbags close at hand.

“It’s just going to continue,” Nickerson said.

The mayor points out an easily overlooked clue about the changing landscape of his village. Outside some houses, unnatural mounds of earth rise from the otherwise pancake-flat ground — an unmistakable sign that an old septic tank has been replaced with a newer, elevated version.

Some mounds are unadorned. Others are neatly landscaped. One resident built an entire deck around what she called the “mountain” in her backyard.

Several years ago, the septic system behind Kristen McLean’s home along the Little River failed as groundwater filled the tank and rendered her plumbing useless. For weeks, she relied on a composting toilet while she had a new engineered system installed.

“When we dug the hole for that septic system, the groundwater was 18 inches below my lawn,” she said. “This little area is a microcosm of what South Florida is up against.”

McClean sold the house in 2021 and jokes that she moved two miles away but seven feet higher.

These days, the mound rising in her old front yard is ringed with native plants.

It’s now a butterfly garden.

About this story

Design and development by Emily Wright .

Photo editing by Sandra M. Stevenson . Video editing by Alice Li and John Farrell . Design editing by Joseph Moore .

Editing by Anu Narayanswamy , Katie Zezima and Monica Ulmanu . Additional editing by Juliet Eilperin . Project editing by KC Schaper . Copy editing by Phil Lueck .

Additional support from Jordan Melendrez, Erica Snow , Kathleen Floyd and Victoria Rossi.

More on climate change

Understanding our climate: Global warming is a real phenomenon , and weather disasters are undeniably linked to it . As temperatures rise, heat waves are more often sweeping the globe — and parts of the world are becoming too hot to survive .

What can be done? The Post is tracking a variety of climate solutions , as well as the Biden administration’s actions on environmental issues . It can feel overwhelming facing the impacts of climate change, but there are ways to cope with climate anxiety .

Inventive solutions: Some people have built off-the-grid homes from trash to stand up to a changing climate. As seas rise, others are exploring how to harness marine energy .

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New report highlights worsening levels of cardiovascular illness and deaths from air pollution.

25 May 2024

Listen to WHF Vice President Elect, Dr Amam MBAKWEM,  talking with the BBC World Service about the air pollution report’s findings and recommendations.

• Air pollution is the greatest single environmental health risk
• Cardiovascular disease is the leading cause of deaths– more than 20 million deaths every year
• Air pollution’s death toll is greatest on those with cardiovascular conditions
• In some regions, air pollution is ten times higher than recommended safe levels

GENEVA, 25 May 2024 – The impact of air pollution on heart disease will lead to millions of preventable deaths every year unless governments introduce legislation to tackle the issue, a new global report warns.

Research by the World Heart Federation shows that the number of deaths from cardiovascular conditions caused by air pollution has been on the rise over the past decade and is set to increase further.

A wide range of health problems, including obesity and diabetes, are being exacerbated by the global policy failure to meet air pollution targets, it says, describing it as “the greatest single environmental health risk”.

The study found that air quality levels have barely improved despite a range of measures recommended by the WHO and other agencies, leading to as many as 1.9 million dying every year from heart disease and just under a million from strokes due to outdoor air pollution alone.

Air pollution comes from many sources, including transport, industry and wildfires, but the report also details how indoor air pollution poses a serious health risk.

Launched at this year’s World Heart Summit , the report reveals the extent of the health crisis caused by outdoor and indoor pollution:

• The number of deaths from heart disease attributable to air pollution has increased in some regions by as much as 27 per cent over the past decade.
• Air pollution is nearly ten times the recommended level in countries in Southeast Asia and the Eastern Mediterranean.
• There are health inequalities between different countries from air pollution in terms of the level of exposure and effect.
• Tiny invisible particles in air pollution are affecting heart rhythm, blood clotting, the build-up of plaques in arteries, and blood pressure, as well as adversely affecting respiratory diseases and other conditions across the body.
• Energy efficiency measures in modern homes as part of net-zero can make buildings more air-tight and could increase the build-up of air pollutants in homes, schools, and workplaces.

Data from the report shows that more than half of the nearly 7 million deaths due to air pollution are from cardiovascular conditions (CVDs), a number that’s been on the rise over the past decade. Experts say the number is likely to be significantly higher as this data is from only a single air pollutant and considers only heart disease and stroke, where as many other cardiovascular diseases are known to be worsened by air pollution. Already, cardiovascular disease is the world’s top killer, claiming more than 20 million lives each year.

The Western Pacific region saw the highest number of deaths from heart disease and stroke due to outdoor air pollution with nearly 1 million deaths in 2019, and the Southeast Asian Region was a close second, with 762,000 deaths. In the Western Pacific region, 45 per cent of the countries have experienced rising air pollution and suffer the highest mortality from stroke and heart disease induced or exacerbated by it.

In Southeast Asia, Africa and the Eastern Mediterranean, air pollution concentrations are nearly ten times higher than recommended. Countries facing the some of greatest challenges with air pollution include those in the Eastern Mediterranean, with Kuwait, Egypt, and Afghanistan having the highest levels of PM2.5 (fine particulate matter in the air). In Africa, the highest levels of PM2.5 were in Nigeria, Niger, and Cameroon.

The report « Clearing the Air to Address Pollution’s Cardiovascular Health Crisis » shows the sources of pollution and their effects on the heart and circulation. Beyond the smoke and smog that we can see, tiny invisible particles can get deep into the lungs, heart, and other organs.

Even short-term exposure to air pollution can have many effects throughout the cardiovascular system, and long-term exposure worsens chronic diseases such as heart disease, stroke, respiratory disease and diabetes. Adverse effects are even seen on mental health, dementia and in pregnancy.

“ Air pollution is ubiquitous, sparing no one. Both outdoor and indoor pollution are driving deaths from cardiovascular disease which still claims the most lives every year. The impacts of air pollution from several sources add up, often widening gaps in healthcare for those also vulnerable to pollution, and worsening outcomes regardless of demographic, ” said Dr Mark Miller of the University of Edinburgh, and the WHF’s Chair of the Air Pollution and Climate Change Expert Group.

Particles that damage air quality vary in composition and size, with PM2.5 being the air pollutant most closely linked to detrimental health effects. The World Health Organisation recommends countries to not exceed 5 micrograms of PM2.5 per cubic metre – expressed as 5 µg/m³. Most are way beyond that threshold, and only 64 per cent have any form of established legislation that include outdoor air quality standards. [i]

While the elderly, children, and those with a lung or heart condition are among those most susceptible to air pollution, short- and long-term exposure affects everyone to varying degrees.   Overall, lower-income countries have higher levels of stroke and ischemic heart disease mortality from both outdoor and household air pollution than higher income countries.

The report shows links between type of disease risk and particular sources of pollution including all major cardiovascular conditions such as heart disease, heart failure, high blood pressure, stroke and many more. The increasing threat of other pollutants is concerning since global air pollution-related healthcare costs are already projected to surge from USD 21 billion in 2015 to USD 176 billion in 2060, with annual lost working days potentially increasing to 3.7 billion by 2060. [ii]

Emphasising today’s visible impacts of air pollution, the new report urges action and targeted investment by governments, health and environment decision-makers, and urban planners. It highlights some countries’ efforts to reduce or mitigate air pollution with strong potential for yielding health and economic benefits, crucial steps given that the urban population is expected to reach nearly 6 billion in the next two decades . [iii]

“We must combat air pollution’s stranglehold that is causing so many unnecessary deaths and ill-health. We need to accelerate the implementation of air quality guidelines and minimise the use of fossil fuels. Improving transport standards, the provision of clean domestic fuels, smart infrastructure, urban design and agricultural policies can all help air quality. The current air pollution crisis in many parts of the world reflects known pollutants and could worsen with the emergence of others, all of which underscores the importance of preventive action now ,” said Dr Miller .

Notes to Editors:

• Exposure and disease burden data: WHO (largely based on ground level measurements)
• WHO methods for PM2.5 estimates:

https://www.who.int/data/gho/data/indicators/indicator-details/GHO/concentrations-of-fine-particulate-matter-(pm2-5)-Metadata

https://www.who.int/data/gho/data/themes/air-pollution/who-air-quality-database/2022

University of Essex, United Kingdom (data pooling and analysis)

• All data based on 2019 estimates
• The first World Heart Report was launched in 2023 showing the impact of cardiovascular disease as the world’s number one killer; this year’s edition takes a closer look at air pollution as one of the top risk factors affecting cardiovascular health.
• The World Heart Federation (WHF) is an umbrella organisation representing the global cardiovascular community, uniting more than 200 patient, scientific and civil society groups. Together with its Members, WHF influences policies, shares knowledge, and inspires behaviour change to achieve heart health for everyone.
• WHF’s science and advocacy resources encompass a range of issues impacting cardiovascular health and this report complements the Policy Brief “ Smart Cities, Healthy Hearts: Action on Air Pollution for Cardiovascular Health .”
• Borjana Pervan , Director of Strategy and Communications, WHF: [email protected] , +41 22 512 0684
• Lisa Hadeed , Senior Communications Officer, WHF:

[email protected] +41 22 512 0693

• Suezelle D’Costa , Associate Director, Hawthorn Advisors:

[email protected] +44 (0)7395 357 869

[i] https://www.unep.org/resources/report/regulating-air-quality-first-global-assessment-air-pollution-legislation

[ii] https://www.oecd.org/environment/indicators-modelling-outlooks/Policy-Highlights-Economic-consequences-of-outdoor-air-pollution-web.pdf

[iii] https://www.worldbank.org/en/topic/urbandevelopment/overview

Discussing the potential WHO pandemic treaty at #wha77

Discussing the general programme of work of WHO at #wha77

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Philippines deploys river rangers in battle against plastic.

Narvas, 30, is one of more than a thousand rangers employed by the government to clean up the city's waterways, where tonnes of rubbish end up every year.

"It's disappointing, because no matter how diligent we are at cleaning up, the garbage does not run out," Narvas told AFP of the never-ending battle against trash.

"But we need to persevere... at least we are managing to reduce it instead of letting it pile up more."

Inadequate garbage collection services, lack of disposal and recycling facilities, and grinding poverty have been blamed for the growing problem of plastic waste across the country.

The Philippines produces about 61,000 tonnes of trash every day, up to 24% of it plastic, figures from the environment department show.

The country is the world's top source of plastic that ends up in the oceans, a 2021 study by Dutch non-profit The Ocean Cleanup found.

It said the Pasig river, which flows through the capital and into Manila Bay, is the "most polluting" in the world.

'Swimming' in plastic

Sachets and other single-use plastics are a huge part of the problem.

"When the rains come, we are literally swimming (in) them," Environment Secretary Maria Antonia Loyzaga said last month.

"But on a daily basis, we consume plastics in the fish caught in our seas, through the substandard water bottles we use and in the very air we breathe," Loyzaga added.

Nieves Denso, a 63-year-old widow, sells small packets of powdered chocolate, coffee, milk, shampoo and detergent from her tiny shop in a riverside slum in Manila.

Sachets are popular in the Philippines, where many people cannot afford to buy household products in large quantities.

Denso collects the empty sachets and every few days she pays children 10 pesos (17 U.S. cents) to take the garbage to a nearby road where she hopes it will be collected.

But she admitted she has no idea if her trash ends up there, or if the children throw it in the river or on vacant land where many of her neighbors discard their waste.

"I put everything in one container and that's it," Denso said when asked if she separates plastic from other waste.

"It's the government's responsibility to make people comply."

'It's disheartening'

Emma Gillego, who lives in a stilt shanty overlooking the Paranaque river, has not seen a garbage truck in her neighborhood since her family moved there 20 years ago.

Plastic litters the ground even though city sanitation workers visit several times a year to teach residents about waste segregation.

"We don't tell off our neighbors who throw garbage into the water because we don't want to meddle with their lives," Gillego, 58, said.

Lawmakers have enacted a series of environmental measures in recent years, covering everything from rolling out recycling centres to compelling companies to take responsibility for their plastic waste.

"The Philippines has made really commendable efforts in pushing all these legislation efforts together," senior World Bank environmental specialist Junu Shrestha told AFP .

While the legislation gave the Philippines a "road map" in dealing with the waste management problem, implementing it was "another challenge," Shrestha said.

In Manila, where more than 14 million people live, only 60% of rubbish is collected, sorted and recycled daily, according to a 2022 World Bank report.

Loyzaga told AFP that the country was in the "infancy stage" of waste segregation and recycling, and she did not see an end to the use of single-use plastic.

"It performs a certain function at the moment for a certain income group in our economy," she said.

While it was unpleasant standing in putrid water for hours on end, river ranger Narvas believed his efforts were helping to reduce flooding in areas along the waterway.

He just wished the community would stop throwing their rubbish in the water.

"It's disheartening," Narvas said.

"But this is our job and we're used to that. We just keep on going."

• Tắt chia sẻ

Researchers issue warning after data shows record-breaking increase in air pollution levels: 'It's sad what we are doing'

C arbon dioxide levels in the atmosphere are rising at an alarming rate, with experts warning that the largest ever recorded increase occurred over the last year.

Carbon concentrations in March 2024 were a staggering 4.7 parts per million higher than in March 2023, according to the Guardian .

What's happening?

Carbon levels have jumped by a record amount over the past 12 months — even higher than the previous record set in 2016, according to levels measured by the National Oceanic and Atmospheric Administration.

Global carbon concentrations hit 421 parts per million in June, a 50% increase compared to pre-industrial times and the highest in millions of years.

Before humans began releasing huge amounts of carbon, levels remained steady at around 280 parts per million for nearly 6,000 years. The current reading from NOAA's Mauna Loa Observatory in Hawaii shows we've now reached about 426 parts per million.

"Human activity has caused CO2 to rocket upwards. It makes me sad more than anything. It's sad what we are doing," said Ralph Keeling, director of the CO2 Program at UC San Diego's Scripps Institution of Oceanography.

Watch now: Delta chief sustainability officer reveals how company plans to appeal to conscious consumers

Why are soaring carbon levels concerning.

This rapid buildup of carbon threatens our communities with more dangerous heatwaves, floods, droughts, and wildfires . The last time levels were this high was around 14 million years ago, leading to a vastly different climate than what people depend on today.

Rising carbon and the resulting climate disruptions put our health, food supply, infrastructure and quality of life at risk. Hotter temperatures will make it harder to grow crops, more flooding will damage homes and businesses, and air pollution from wildfires will worsen respiratory illnesses. 

The impacts will touch all our lives.

What's being done about record carbon levels?

While the situation is serious, there are solutions that can turn this trend around for a safer future.

On a large scale, transitioning to clean energy, such as wind and solar power , to run our electric grid is key to reducing pollution.

As individuals, saving energy at home, choosing public transit or EVs over gas cars, and eating more plants over meat all cut carbon. Planting trees is another great way to remove existing carbon from the air.

By taking action in our own lives and supporting policies to expand clean energy, we can build healthier communities and get carbon back to sustainable levels. The more we each do now, the better off we'll be later.

Join our free newsletter for cool news and cool tips that make it easy to help yourself while helping the planet.

Researchers issue warning after data shows record-breaking increase in air pollution levels: 'It's sad what we are doing' first appeared on The Cool Down .

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Snow and rising sea levels may have triggered Japan's earthquake swarm

In an ongoing swarm of earthquakes that began hitting Japan in 2020, the shifting weight of surface water may have spurred the shaking

By James Dinneen

21 May 2024

Snow may have weakened fractures and faults underground and contributed to earthquakes in Japan

Suzuki Kaku/Alamy

A years-long swarm of thousands of earthquakes in Japan was probably triggered by heavy snow and other environmental factors such as rain and rising sea levels.

“The changing climate can have some impact on the stress state of the Earth beneath our feet,” says Qing-Yu Wang at the Massachusetts Institute of Technology. But the role human-caused climate change played in these quakes remains uncertain, she says.

The uncomfortable reality of life on Earth after we breach 1.5°C

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