ground water essay

Groundwater: Making the invisible visible in 2022 and beyond

UNESCO, together with its centre, the International Groundwater Resources Assessment Centre (IGRAC), has led the World Water Day 2022 campaign on “Groundwater: Making the invisible visible” on behalf of UN-Water; the campaign will remain active throughout the year. UNESCO will coordinate the organization and will participate in a series of key events related to groundwater, aimed at conveying a message about the importance of these hidden resources to the UN 2023 Water Conference.

World Water Day

22 march 2022.

Since its inception in 1975, the UNESCO Intergovernmental Hydrological Programme (IHP) has provided a substantial contribution to the improved knowledge of groundwater and aquifers worldwide. UNESCO, together with its category 2 centre, IGRAC, has led the U N World Water Day 2022 campaign on “Groundwater: Making the invisible visible” on behalf of UN-Water. The UN World Water Development Report (WWDR) 2022 , prepared by the UNESCO's World Water Assessment Programme (WWAP), and published by UNESCO on behalf of UN-Water and its partners, was this year devoted to the topic, providing the most up-to-date knowledge on groundwater.

More information

World Water Forum

21-26 march 2022, dakar, senegal.

The World Water Forum is the largest international event dedicated to water, bringing together NGOs, the private sector, governments and international organizations. It is organized by the Forum’s respective host country and the World Water Council, with IHP, the intergovernmental platform for water within the UN system, also taking an important role. The Forum aims to raise awareness among decision-makers and the public at large on water issues and to generate action, thus improving access to water supply and sanitation. It also reports on the progress taken towards meeting the UN Sustainable Development Goals.

Within the framework of the 9th World Water Forum, UNESCO and IGRAC took the lead in the celebration of the World Water Day (22 March 2022) on the theme, “Groundwater: Making the invisible visible”, and organized the following sessions:

Check all the events UNESCO organized by or with participation of UNESCO during the 9th World Water Forum

Groundwater, Key for Sustainable Development Goals

18-20 may 2022.

The main objectives of the May 2022 International Conference “ Groundwater, key to the Sustainable Development Goals ” are to :

Examine the overall relationships between water-related Sustainable Development Goals', their stakeholders and groundwater
Share knowledge, experiences, findings and good practices on the groundwater resources in sustainable development issues
Elaborate recommendations to ensure the best integration of groundwater resources into the SDGs

The conference is co-organized by the French Chapter of the International Association of Hydrogeologists (CFH-AIH), UNESCO’s Intergovernmental Hydrological Programme (UNESCO IHP), and the French Water Partnership (FWP), under the patronage of the French National Commission for UNESCO and with the support of the French Ministry of the Ecological Transition, the Seine-Normandy Water Agency, and Sorbonne University.

Dushanbe High-level Water Conference

6-9 june 2022.

The Second Dushanbe Water Action Decade Conference, organized by the Government of the Republic of Tajikistan with the support of the United Nations and other partners, will focus on how governments, the United Nations and its entities, other international and regional organizations, international financial institutions, the private sector, civil society organizations, academia, communities, local governments and other stakeholders can catalyze water action and partnerships to contribute to the implementation of water-related goals and targets of the 2030 Agenda for Sustainable Development, the Paris Climate Agreement, the Sendai Framework for Disaster Risk Reduction, the Addis Ababa Action Agenda on Financing for Development and the New Urban Agenda at all levels, while supporting the global response to the COVID-19 crisis.

The Conference will be held on 6-9 June 2022 at Kokhi Somon, Dushanbe, Republic of Tajikistan. The Conference program includes opening and closing ceremonies, a plenary session, several thematic and interactive panels, special forums for regional and major groups, as well as side events.

World Water Week

23 august-1 september 2022, on-line and stockholm, sweden.

World Water Week is the leading annual event on global water issues, organized by Stockholm International Water Institute (SIWI) since 1991. Together with organizations from all sectors and all regions of the world, SIWI seeks solutions to the world’s greatest water-related challenges. In 2022, the UNESCO Intergovernmental Hydrological Programme (IHP), as Key Collaborating Partner, will join efforts with the World Water Week 2022 to highlight the importance of groundwater resources for human and ecosystems and jointly contribute to improve knowledge and capacity to accelerate the achievement of the Sustainable Development Goal 6 on water and sanitation (SDG 6) for a water secure world.

UN-Water Summit on Groundwater

7-8 december 2022, unesco headquarters, paris, france.

The UN-Water Summit on Groundwater organized by UNESCO and its International Groundwater Resources Assessment Centre (IGRAC) will take place in 7-8 December 2022 at UNESCO HQ, Paris, and is planned as a hybrid meeting with the most possible on-site presence. The 6 December will be a Pre-Summit day, devoted to side events only .

The Summit aims to make groundwater more visible in order to better manage and protect it. It will bring attention to groundwater at the highest international level and will use the World Water Development Report 2022 as a baseline and the SDG 6 Global Acceleration Framework as a guideline to define actions towards more responsible and sustainable use and protection of this vital natural resource.

The summit will unify the statements from all major groundwater-related events in 2022 in one comprehensive groundwater message for the UN Water Conference 2023.

Other events

The 12th International Hydrogeological Conference: "Groundwater resources in an ever-changing environment" Nicosia, Cyprus, 20-22 March 2022
Eurokarst 2022 Malaga, Spain, 22-24 June 2022
Side event of the High-level Political Forum (HLPF) : “Climate impacts from cryosphere to groundwater” New York, July 2022
XXII Brazilian Groundwater Congress "Groundwater: Invisible, Indivisible and Indispensable” São Paulo, Brazil, 2-5 August 2022
Presentation of the 2023 World Water Day and World Toilet Day World Water Week, Stockholm, 28 August
77th United Nations General Assembly: Debate of the Legal Committee on “The Law of Transboundary Aquifers” 19 October 2022
49th IAH Congress "Groundwater Sustainability and Poverty Reduction " Wuhan, China, 18-23 September 2022
UN Climate Change Conference 2022 (UNFCCC COP 27) 7-18 November 2022
World Toilet Day 2022 19 November 2022

More on this subject

First Meeting of the Ad Hoc Expert Group for the elaboration of a draft Recommendation on the Ethics of Neurotechnology

Water Q&A: How important is groundwater? Completed

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Learn how important groundwater is to some communities.

• Water Science School HOME • Water Science Q&As •

How important is groundwater?

Groundwater, which is in aquifers below the surface of the Earth, is one of the Nation's most important natural resources. Groundwater is the source of about 33 percent of the water that county and city water departments supply to households and businesses (public supply). It provides drinking water for more than 90 percent of the rural population who do not get their water delivered to them from a county/city water department or private water company. Even some major cities, such as San Antonio, Texas, rely solely on groundwater for all their needs. In 2015, about 48 percent of the water used for irrigation comes from groundwater. Withdrawals of groundwater are expected to rise as the population increases and available sites for surface reservoirs become more limited.

About 29 percent of the freshwater used in the United States in 2015 came from groundwater sources. The other 71 percent came from surface water. Groundwater is an especially important natural resource in those parts of the country that don't have ample surface-water sources, such as the arid West. It often takes more work and costs more to access groundwater as opposed to surface water, but where there is little water on the land surface, groundwater can supply the water needs of people.

Essay on Importance Of Groundwater

Students are often asked to write an essay on Importance Of Groundwater 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 Importance Of Groundwater

What is groundwater.

Groundwater is water found under the ground in the cracks and spaces in soil, sand, and rocks. It is stored in and moves through geologic formations of soil, sand, and rocks called aquifers.

Groundwater as a Water Source

Groundwater is a key source of water for drinking and farming. Many towns and cities get their drinking water from it. Farmers use it to grow crops and feed animals. Without it, our taps would run dry and food would be scarce.

Groundwater and Nature

Groundwater is also crucial for nature. It keeps rivers and lakes full, supports plants, and helps animals survive. It plays a big part in keeping the environment healthy.

Groundwater Challenges

Groundwater can get polluted, and it’s hard to clean. We must keep it clean because cleaning it is difficult and expensive. Also, if we use too much, there might not be enough in the future.

Protecting Groundwater

We must protect groundwater by using it wisely and keeping it clean. This means not wasting water and stopping harmful chemicals from getting into the ground. It’s important for our health and the planet.

250 Words Essay on Importance Of Groundwater

Groundwater is the water that soaks into the ground and collects in spaces between rocks and soil. It is a hidden treasure that helps keep our rivers, lakes, and wells filled with water. Imagine it as a giant underground lake that we can’t see.

Drinking and Cooking

One of the main uses of groundwater is for drinking. Many towns and cities get their water from wells that pull groundwater up to the surface. This water is often clean and safe to drink. It’s also used for cooking and cleaning in homes.

Farming Needs

Farmers rely on groundwater to water their crops. When it doesn’t rain much, they use pumps to bring groundwater to the surface. This helps plants grow and provides food for us to eat.

Keeping Rivers Flowing

Groundwater is important for rivers and lakes. During dry times, groundwater seeps out and keeps these bodies of water from drying up. This is good for the fish and animals that need rivers and lakes to live.

Problems When It’s Gone

If we use too much groundwater, we can face big problems. Wells can run dry, and land can sink if too much water is taken out. Also, if we pollute the ground, the groundwater can become dirty and unsafe.

It’s important to use groundwater wisely and keep it clean. We can save it by using less water in our daily lives and making sure we don’t pollute the land. Groundwater is a precious resource that we need to take care of for ourselves and future generations.

500 Words Essay on Importance Of Groundwater

What is groundwater.

Groundwater is water that is found under the ground in spaces between sand, soil, and rocks. It is stored in and moves slowly through layers of soil, sand, and rocks called aquifers. Imagine it like a hidden treasure of water, which is very important for our daily life.

Drinking Water Source

One of the main reasons groundwater is so important is that many people around the world get their drinking water from it. In some places, there are no rivers or lakes, so the only choice for water is from the ground. This water is often clean and safe to drink because the soil acts like a filter, cleaning the water as it moves through it.

Farming and Food

Farmers need water to grow crops and feed animals. Groundwater is used to water plants when there isn’t enough rain. Without groundwater, we might not have enough food to eat. It helps plants grow, which in turn gives food to animals and people.

Nature’s Balance

Groundwater is also important for the environment. It keeps the ground wet, which is important for plants to grow. It also feeds rivers and lakes, which are homes for fish and other wildlife. Without groundwater, these places could dry up and the living things that need them could die.

Keeps Us Safe During Droughts

Sometimes, it doesn’t rain for a long time. This is called a drought. During a drought, rivers and lakes can dry up. But if we have groundwater, we can still have water. It’s like a backup supply that helps us when there’s no rain.

Problems with Using Too Much Groundwater

Even though groundwater is very useful, we have to be careful. If we take too much water from the ground, there can be problems. The ground might sink if there’s not enough water to hold it up. Wells can run dry, and there might not be enough water for people, farms, and animals. We need to use groundwater wisely and make sure there’s enough for the future.

Keeping Groundwater Clean

It’s important to keep groundwater clean. If it gets dirty from things like chemicals or waste, it can be harmful to drink and can hurt animals and plants. Cleaning dirty groundwater is very hard and expensive, so we must protect it from getting dirty in the first place.

Groundwater is like a secret underground treasure that we all depend on. It gives us water to drink, helps farmers grow food, keeps nature healthy, and is a safe backup when there’s no rain. We must take care of it so that it stays clean and available for us and for future generations. Remember, every drop of water is precious, and groundwater is a big part of that precious water.

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

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A growing population and an increased demand for water resources have resulted in a global trend of groundwater depletion. Arid and semi-arid climates are particularly susceptible, often relying on groundwater to support large population centers or irrigated agriculture in the absence of sufficient surface water resources. In an effort to increase the security of groundwater resources, managed aquifer recharge (MAR) programs have been developed and implemented globally. MAR is the approach of intentionally harvesting and infiltrating water to recharge depleted aquifer storage. California is a prime example of this growing problem, with three cities that have over a million residents and an agricultural industry that was valued at 47 billion dollars in 2015. The present-day groundwater overdraft of over 100 km3 (since 1962) indicates a clear disparity between surface water supply and water demand within the state. In the face of groundwater overdraft and the anticipated effects of climate change, many new MAR projects are being constructed or investigated throughout California, adding to those that have existed for decades. Some common MAR types utilized in California include injection wells, infiltration basins (also known as spreading basins, percolation basins, or recharge basins), and low-impact development. An emerging MAR type that is actively being investigated is the winter flooding of agricultural fields using existing irrigation infrastructure and excess surface water resources, known as agricultural MAR. California therefore provides an excellent case study to look at the historical use and performance of MAR, ongoing and emerging challenges, novel MAR applications, and the potential for expansion of MAR. Effective MAR projects are an essential tool for increasing groundwater security, both in California and on a global scale. This chapter aims to provide an overview of the most common MAR types and applications within the State of California and neighboring semi-arid regions.

Publisher ijmra.us UGC Approved

United States also has been facing severe water crisis. There are hundreds of cities and towns in US that are at severe risk of sudden and severe shortage. Water scarcity is in fact ranked as a major threat to national security alongside terrorism by the U.S. Office of the Director of National Intelligence. California's rivers, groundwater provides about a third to half of the state's water supply and it has been a leader in many types of environmental management, but groundwater has been an exception to that rule. The crisis has been blamed on climate factors but deep insights shows that it is more due to shortcomings of governance and policy actions. Absence of timely statewide framework for managing this resource would put the danger the rights of future generations. Apart from recent legislative action more concrete actions at policy levels, more judicious use of water and actions to conserve resources is the only hope for California's long-term water security and sustainability.

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Groundwater

Groundwater is the water present below the earth’s surface and is a vast resource of water. Almost 22 percent of water is below the surface land in the form of groundwater. Groundwater is important as it is used for water supply in rural and urban areas. It is also often used for municipal, industrial and agricultural use by building and operating extraction wells.

The groundwater is more convenient and less exposed to pollution. So, it is commonly used as water supplies for the public.
Groundwater makes up about twenty percent of the freshwater supply of the entire world’s water, including oceans and permanent ice.

Groundwater Pollution

Generally, groundwater is good for drinking. Groundwater that is polluted is less visible and difficult to clean up than lakes and rivers. Most often groundwater pollution results from the disposal of wastes improperly including household and industrial chemicals, wastewater from mines, leaking underground oil storage, oil field brine pits, garbage landfills, and sewage systems.

Prevention of groundwater pollution can be done by:

storing rainwater
watertight materials
collecting leachate with drains

What are Porosity and Permeability?

Porosity: It is a measure of the void spaces (pores) that exist between particles of clay, grains of sand, or pieces of gravel, in the layer. It is usually expressed as a fraction of the volume of void space divided by the total volume, and written as a percentage between 0–100%.

Permeability: It refers to the ability of water to move between these pore spaces.

Porosity and Permeability Ranges for Sediment:

Groundwater recharge.

Groundwater recharge is also known as deep percolation or deep drainage. It undergoes the hydrologic process, which moves surface water to groundwater. It is a primary method where water enters an aquifer. The recharge occurs at plant roots and is often known as a flux to the water table surface.

Types of groundwater recharge:

Water Cycle: Naturally, through the water cycle .

Anthropogenic Processes: Anthropogenic process is also called artificial groundwater recharge, where rainwater and reclaimed water is routed to the subsurface.

Frequently Asked Questions – FAQs

What is meant by groundwater, what is the importance of groundwater, what is groundwater pollution, what are the solutions to preserve groundwater, what is meant by permeability.

Put your understanding of this concept to test by answering a few MCQs. Click ‘Start Quiz’ to begin!

Select the correct answer and click on the “Finish” button Check your score and answers at the end of the quiz

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Open access
Published: 08 April 2024

Underestimated burden of per- and polyfluoroalkyl substances in global surface waters and groundwaters

Diana Ackerman Grunfeld 1 ,
Daniel Gilbert 1 ,
Jennifer Hou 1 ,
Adele M. Jones ORCID: orcid.org/0000-0001-6427-0876 1 ,
Matthew J. Lee 1 ,
Tohren C. G. Kibbey ORCID: orcid.org/0000-0003-0304-6058 2 &
Denis M. O’Carroll ORCID: orcid.org/0000-0001-6557-226X 1

Nature Geoscience volume 17 , pages 340–346 ( 2024 ) Cite this article

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Per- and polyfluoroalkyl substances (PFAS) are a class of fluorinated chemicals used widely in consumer and industrial products. Their human toxicity and ecosystem impacts have received extensive public, scientific and regulatory attention. Regulatory PFAS guidance is rapidly evolving, with the inclusion of a wider range of PFAS included in advisories and a continued decrease in what is deemed safe PFAS concentrations. In this study we collated PFAS concentration data for over 45,000 surface and groundwater samples from around the world to assess the global extent of PFAS contamination and their potential future environmental burden. Here we show that a substantial fraction of sampled waters exceeds PFAS drinking water guidance values, with the extent of exceedance depending on the jurisdiction and PFAS source. Additionally, current monitoring practices probably underestimate PFAS in the environment given the limited suite of PFAS that are typically quantified but deemed of regulatory concern. An improved understanding of the range of PFAS embodied in consumer and industrial products is required to assess the environmental burden and develop mitigation measures. While PFAS is the focus of this study, it also highlights society’s need to better understand the use, fate and impacts of anthropogenic chemicals.

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Wei Zhi, Alison P. Appling, … Li Li

Per- and polyfluoroalkyl substances (PFAS) constitute a class of over 14,000 1 chemicals extensively used in industrial applications and consumer products because of their distinct water and oil repellent properties and high heat tolerance. PFAS are defined as fluorinated substances that contain at least one fully fluorinated methyl or methylene carbon atom 2 . This includes fluoropolymers (for example, Teflon), some fluorinated insecticides (for example, Fludioxonil) and pharmaceuticals (for example, Bicalutamide) 3 . PFAS are referred to as ‘forever chemicals’ 4 because of their persistence in the environment. Perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), two of the highest-profile PFAS, were added to the Stockholm Convention for the protection of human health and the environment from persistent organic pollutants (POPs) 5 in 2009 and 2019, respectively, limiting their use and production. This also coincided with a shift from ‘legacy PFAS’ towards novel PFAS 6 (Extended Data Table 1 ).

Regulators worldwide have proposed or regulated varying concentrations for PFAS in drinking water. One of the most restrictive recommendations for drinking water is Health Canada’s, with the sum of all PFAS being less than 30 ng l −1 (ref. 7 ), whereas the European Union recommends the sum off all PFAS being less than 500 ng l −1 or the sum of 20 select PFAS being less than 100 ng l −1 (ref. 8 ). It is noted, however, that currently Health Canada only requires quantification of either at least 18 PFAS or using US Environmental Protection Agency (EPA) methods 533 and/or 537.1 9 . The US EPA has proposed drinking water concentration limits of 4 ng l −1 for PFOS and PFOA in their National Primary Drinking Water Regulation and limits on perfluorononanoic acid (PFNA), perfluorobutanesulfonic acid (PFBS), perfluorohexanesulfonic acid (PFHxS) and hexafluoropropylene oxide dimer acid (GenX) through the hazard index (HI) 10 .

Toxicity concerns increase with fluorinated chain length (FCL), because long-chain PFAS (FCL > 6) usually take longer to be excreted from the body due to their lower water solubility, higher affinity for serum proteins and enterohepatic recirculation, which increase their elimination time from plasma and tissue 11 , 12 , 13 . All perfluoroalkyl carboxylic acids (PFCA) with a FCL ≥ 7 are currently candidates for potential inclusion on the Stockholm Convention for the protection of human health and the environment from POPs 5 .

Certain PFAS degrade to terminal perfluoroalkyl carboxylic acids (PFCAs) and perfluoroalkyl sulfonic acids (PFSAs) and are referred to as precursors 14 (Supplementary Table 1 and Supplementary Fig. 1 ). Precursors are used extensively in the manufacture of consumer products such as cosmetics, surface treated paper, waterproof textiles, insecticides, food packaging and firefighting foams 15 . Whereas there are too many PFAS precursors to list individually, they are generally separated into three major groupings: fluorotelomers, sulfonamides and polyfluorinated alkyl phosphate esters (PAPs).

Whereas studies have estimated PFAS production globally 16 , 17 and quantified PFAS in commercial and industrial products, their fate is still unknown. Numerous studies have investigated PFAS extent in environmental compartments, including one that suggests that four select PFAS exceed the planetary boundary 18 . Studies have also assessed or compared aqueous phase PFAS concentrations in select regions 19 , 20 . Whereas it is widely acknowledged that PFAS are globally pervasive, the extent of PFAS in global surface (SW) and groundwater (GW) is unknown, as is the extent to which PFAS concentrations exceed proposed or implemented PFAS drinking water guidelines.

Here we investigate the extent and distribution of PFAS surface and groundwater contamination globally. We assess PFAS concentrations with respect to current and proposed PFAS drinking water regulations or advisories. Finally, we investigate the source of PFAS contamination, including the distribution of PFAS used in various consumer products, providing insights into the global pervasiveness of PFAS and the ability to predict the future environmental burden of PFAS.

Extent of global PFAS water contamination

To assess the global extent and importance of PFAS in the environment, an extensive global dataset was developed from 273 environmental studies since 2004, which include data for over 12,000 SW and 33,900 GW samples. As PFAS are not naturally occurring 21 , any PFAS found in the environment was introduced from a range of consumer and industrial products.

PFAS are pervasive in SW and GW worldwide (Fig. 1 ). Note that, while the mapped data suggest Australia, China, Europe and North America are PFAS hotspots relative to the world (Fig. 1a ), when comparing against the number of samples collected (Fig. 1b ), it implies that these are high-sampling zones, potentially skewing the representation of actual distribution. If research were undertaken in more locations worldwide at sites with high aqueous film forming foam (AFFF) usage, such as major airports, comparable PFAS contamination levels would probably be found. Additionally, high PFAS contamination in Fig. 1a is not limited to areas near manufacturing sites but also high-use areas. For example, Australia has no PFAS manufacturing facilities 22 , 23 but has highly contaminated PFAS sites from firefighting activities. Furthermore, sampled locations could have higher PFAS concentrations compared to unsampled areas, as research efforts tend to concentrate on locations where PFAS presence is likely. Given this, the occurrence of surface and groundwater with large PFAS concentrations estimated in this study may be high.

a , Sum of concentration of 20 PFAS subject to EU guidance in surface water, groundwater and drinking water samples. Those above the EU drinking water limit of 100 ng l −1 (marked red on scale bar) are circled in red (for known contamination sources (for example, AFFF or non-AFFF)) or black (unknown sources). b , Number of PFAS samples available on a 5° longitude/latitude grid worldwide.

Source data

Threshold regulatory PFAS concentration limits are used to benchmark the PFAS global extent in SW and GW (Extended Data Table 2 ). PFAS sources were divided into three categories: known non-AFFF (for example, production facilities using or producing PFAS, landfills), known AFFF (for example, firefighting training area) or unknown. A higher proportion of samples exceeded threshold limits when associated with a known source of PFAS contamination compared with an unknown source (Fig. 2 and Extended Data Figs. 1 – 6 ). For GW samples with known AFFF contamination, 71, 72 and 63% exceeded the proposed US EPA HI ( n = 6,312) or their proposed PFOS ( n = 6,442) and PFOA ( n = 6,447) drinking water regulation, respectively. However, when there was no known source, the incidence of exceedance of these criteria was still elevated (31, 50 and 40% for the US EPA HI ( n = 14,905), PFOS ( n = 15,351) and PFOA ( n = 15,499) drinking water regulation, respectively). Given that guidance on PFAS threshold concentrations vary globally, the proportion of samples that are deemed of concern also varies. Groundwater with no known contamination source exceeded Health Canada’s criteria in 69% of samples whereas only 6% of these samples exceeded the EU’s sum of all PFAS criteria (500 ng l −1 ) ( n = 16,151). If the alternate EU sum of 20 PFAS criteria is considered, 16% of groundwater samples with no known contamination source were in exceedance ( n = 16,143). Regardless of the regulatory threshold considered, a large fraction of groundwater samples would be considered unacceptable for drinking water consumption. For known AFFF source SW samples, the proportion exceeding regulatory thresholds is similar to GW samples. However, when there was no known PFAS source, or a known non-AFFF source, the incidence of SW samples exceeding regulatory thresholds was lower. This is expected as residence times in surface waters are lower than for groundwater. For this analysis, samples that were below detection limits (BDL) were randomly assigned a concentration between zero and the detection limit. To assess potential bias, particularly for low-threshold criteria jurisdictions (for example, PFOA < 4 ng l −1 US EPA), this analysis was repeated with PFAS concentrations with BDL set to zero (Extended Data Table 3 and Supplementary Figs. 2 – 8 ). Whereas assumptions made dealing with detection limits impact results, both approaches conclude that an important fraction of samples exceeds regulatory threshold levels. As method-detection limits continually decrease, the extent of exceedances will be better informed.

For samples where PFAS concentrations were below detection limits, a PFAS concentration was randomly assigned between zero and the detection limit.

Where does PFAS come from

To assess PFAS sources to the environment, consumer and industrial products containing PFAS were divided into those used for AFFF and non-AFFF. AFFF applications typically result in high concentration point sources of PFAS, as do industrial manufacturing sites that synthesize or use PFAS. The latter are considered known (non-AFFF) sources in this study.

Non-AFFF consumer and industrial products

PFAS in 943 non-AFFF consumer products in 15 categories were characterized from 38 literature studies since 2010. In these studies, 113 PFAS were quantified, although at most 60 PFAS were analysed in any given study 24 . Comparison of PFAS classes in consumer products is challenging as the same suite of PFAS are not quantified in each study. For example, at least two PFCAs or PFSAs were measured in 89% and 69% of all non-AFFF product samples, respectively, whereas only 49%, 35%, 20%, 12% and 15% of studies quantified at least two fluorotelomers, sulfonamides, PAPs, novel or other PFAS, respectively. When measured, however, fluorotelomers and traditional PFCAs represented the dominant PFAS subclass in most of the product categories investigated (for example, coatings, cosmetics and textiles) (Fig. 3 ). Fluorotelomers represented a median of 72% of the total measured PFAS by mass in consumer products, whereas PFCAs represented 25%. PAPs and sulfonamides were also relevant when measured with a median of 14% and 7%, respectively. Interestingly, PFSAs were typically much lower, accounting for a median of 4% of the total quantified PFAS mass.

Box dimensions show the span between quartiles 1 and 3 (interquartile range, IQR). Outliers are defined as values greater than 1.5× the IQR. Whiskers extend from these quartiles to the largest (quartile 3) or smallest (quartile 1) non-outlier value (that is, <1.5× the IQR). Y -axis units are ng ml −1 or µg kg −1 equivalent to ppb.

Different jurisdictions worldwide provide guidance, or regulate, differing ranges of PFAS, with no standard approach to quantify PFAS. For example, the US EPA has three methods to measure PFAS in aqueous samples, methods 533, 537.1 and 8327, with an additional non-drinking aqueous method (1633) in development. EPA method 537 and its revisions have been the most used since 2009, quantifying 14 PFAS. In 2018, this method was revised as 537.1 to include four additional PFAS. All other EPA methods were developed in 2019 or later and quantify a total of 32 PFAS, including seven PFSA, 11 PFCA, three fluorotelomers, three sulfonamides and eight novel PFAS (Extended Data Table 2 ). In this study, EPA draft method 1633 is used as a benchmark as EPA methods are commonly used globally and method 1633 is the most comprehensive. In doing so, this provides a preliminary assessment of the extent to which the most comprehensive EPA method captures PFAS mass and the extent of unaccounted PFAS.

If only the PFAS listed in draft method 1633 were used to quantify PFAS in consumer products within this dataset, the total embodied PFAS would be substantially underestimated (Fig. 4 ) and the PFAS distribution would completely change. For example, the median concentration of PFAS regulated in the United States (sum of PFBS, PFHxS, PFOS, PFOA, PFNA and GenX) in textiles ( n = 227) and coatings ( n = 167) is two and three orders of magnitude smaller than the median of all PFAS quantified. Across all products, EPA method 1633 suggests a median distribution of 73% PFCA ( n = 781), 11% PFSA ( n = 750), 16% fluorotelomers ( n = 353), 10% sulfonamides ( n = 242) and 0.1% novel PFAS ( n = 27), with phosphate-based PFAS not being quantified with this method. This results in the proportion of PFCAs, PFSAs and sulfonamides being overestimated by a factor of 2.8, 2.8 and 4.2, respectively, whereas fluorotelomers would be underestimated by a factor of 25. A median of 4% of the PFAS mass in consumer products is currently subject to the Stockholm Convention ( n = 976), increasing to 18% with the inclusion of candidate PFAS (PFCAs with FCL ≥ 7) ( n = 976). The average amount of long-chain PFAS within this dataset, including PFCAs, is 66% ( n = 976), indicating that long-chain PFAS are dominant in consumer products.

PFAS concentrations are in ng ml −1 or µg kg −1 equivalent to ppb. Box dimensions show the span between quartiles 1 and 3 (IQR). Outliers are defined as values greater than 1.5× the IQR. Whiskers extend from these quartiles to the largest (quartile 3) or smallest (quartile 1) non-outlier value (that is, <1.5× the IQR).

As previously mentioned, fluorotelomers represent the largest contributor to PFAS mass in consumer products. Fluorotelomers are comprised of numerous subgroups including fluorotelomer sulfonates (FTS), fluorotelomer alcohols (FTOH), fluorotelomer iodides, fluorotelomer acrylates, fluorotelomer methacrylates, fluorotelomer mercaptoalkyl phosphate diester, fluorotelomer unsaturated carboxylic acids (FTUCA) and fluorotelomer carboxylic acids (FTCA). FTS represent a median 2% ( n = 338) of the total PFAS in consumer products when two or more PFAS classes are quantified and are the only fluorotelomers quantified using the US EPA methods. FTOH require a different analytical method to most other PFAS and were not often analysed. However, when two or more PFAS in this subclass were quantified, they represented an important proportion (median of 58% ( n = 365)) of the total PFAS in consumer products.

Although most PFAS in consumer products may not be currently regulated, many will transform to regulated PFAS in the environment (Supplementary Tables 1 and 2 ). Studies that have used the total oxidizable precursor (TOP) assay found a notable increase in PFCAs following oxidation. This suggests that traditional EPA-based methods do not adequately capture PFAS embodied in consumer products and their potential environmental burden 24 , 25 , 26 , 27 .

Eleven literature studies characterize PFAS in 148 AFFF samples from different suppliers and synthesis methods sold since 1980. These studies quantified 69 PFAS with a maximum of 40 PFAS being measured in any given study 28 . PFAS for AFFF applications have been synthesized by two synthesis processes: electrochemical fluorination and telomerization 21 . These processes result in a range of products with electrochemical fluorination-producing PFOS and telomerization-producing fluorotelomers 21 , 29 . Depending on the manufacturer and year produced, AFFF has different formulations (Supplementary Table 3 ). PFOS represents a median 51% of the PFAS in historic 3M AFFF ( n = 14), with other PFSAs and sulfonamides also forming important contributions. All other PFAS in historic 3M AFFF had low concentrations, when measured. Fluorotelomers and PFCAs, were the dominant PFAS in Angus AFFF ( n = 28), with a median of 64% and 36%, respectively. Several other AFFF have been investigated, however, the supplier’s name was not provided or PFCA and PFSA concentrations were not quantified. In these samples, fluorotelomers represented the dominant PFAS (median = 93%, n = 83). Of these fluorotelomers, important subclasses include FTS (median = 73% of total PFAS, n = 69) and FTOH (median = 10% of total PFAS, n = 38). Comparison of PFAS quantified using EPA method 1633 to the sum of all PFAS quantified suggests that exclusively reporting PFAS quantified using EPA method 1633 underrepresents total PFAS in AFFF by a median factor of 2.8. A median 60% of the PFAS mass in historic 3M AFFF is subject to the Stockholm Convention whereas Angus AFFF has no PFAS subject to the Stockholm Convention. For non-3M AFFF ( n = 134), including candidate PFAS, 0.6% of the PFAS mass would be subject to the Stockholm Convention, increasing to 1% if long-chain PFAS are considered. This analysis of AFFF formulations suggests that known PFAS in AFFF presents a large environmental burden, with an important fraction either currently subject to regulatory oversight, or likely in future. However, an undetected fraction of PFAS in AFFF probably exists 30 . It is important to note that many of these studies quantify a limited number of PFAS, similar to non-AFFF product studies. Therefore, it is challenging to predict the AFFF environment burden because not all PFAS are quantified. Furthermore, when the TOP assay is applied to AFFF samples, considerable increases in total PFAS mass has been reported 31 , 32 , as noted in non-AFFF consumer product studies.

Finding the missing piece in FTOH and other under measured PFAS

Across the 33,940 groundwater samples, 57 distinct PFAS were quantified. On average, 16 distinct PFAS (maximum of 38 PFAS) were quantified and an average of 15 PFAS within the suite of proposed US EPA method 1633. PFCAs, PFSAs and sulfonamides were routinely quantified (at least two PFCAs, PFSAs and sulfonamides were quantified in 91%, 89% and 54% of studies, respectively). Whereas at least two fluorotelomers were quantified in 26% of the groundwater studies, this was almost exclusively FTS, with FTCA and FTUCA quantified to a lesser extent and no studies quantifying FTOH. This is despite the fact that FTOH are an important PFAS present in consumer products, when quantified. It is important to note that existing EPA aqueous methods (EPA methods 533, 537, 1633) are liquid chromatography with tandem mass sprectrometry (LC-MS/MS) based. Analysis of FTOH requires gas chromatography tandem mass spectrometry (GC-MS/MS), with no US EPA GC/MS/MS methods for aqueous PFAS in existence. With regards to surface water, PFCAs, PFSAs and fluorotelomers were quantified to a similar extent as groundwater samples, with FTS representing the dominant fluorotelomers quantified. Unlike groundwater studies, four of the surface water studies quantified FTOH 33 , 34 , 35 , 36 , with only two also quantifying PFCAs, PFSAs or both, facilitating an assessment of the relative importance of FTOH. In the 16 urban river samples in China 34 and eight river samples in Bangladesh 33 , FTOH represented a median of 53% of the total PFAS (range of 46 to 62%) and 2% (ranging from 0.9 to 34%), respectively. It is difficult to draw definitive conclusions from two studies with relatively few samples, however, coupled with the FTOH prevalence in consumer products, it suggests that FTOH could be an important class of unquantified PFAS. Because only a limited suite of PFAS are typically quantified, any estimate of PFAS environmental burden is likely to be an underestimate, and a broader suite of PFAS needs to be quantified.

Wastewater treatment plants (WWTPs) and landfills are focal point receptors of anthropogenic activity. Hence, representing an opportunity for quantification of the diverse PFAS suite that has or may be dispersed into the environment. Unfortunately, studies investigating WWTP influent and landfill leachate provide limited insights. Whereas landfill leachate studies quantify more PFAS than surface and groundwater studies, they have focused on the same range of PFAS (PFCAs, PFSAs, FTS and select sulfonamides) with no studies directly measuring FTOH 37 . However, studies have reported atmospheric FTOH emissions at landfill sites and WWTPs 38 . One Chinese study reported FTOH represented 8% of the PFAS WWTP influent mass 39 . FTOH could enter the wastewater system through various sources, including laundering of textiles 40 .

Studies using the TOP assay to WWTP effluent report a considerable PFAS fraction that go undetected using EPA methods 41 , 42 . Similarly, studies that oxidized landfill leachate reported minimum to moderate changes in PFAS concentrations, suggesting that unknown PFAS transformed biotically or abiotically in landfill cells 43 , 44 . Whereas limited studies have applied the TOP assay to surface and groundwater, some report considerable increases in PFAS concentrations, although the increases are not consistent in the literature 41 , 45 , 46 . A major drawback of the TOP assay is that not all PFAS undergo oxidation to PFCAs or PFSA, particularly the perfluoroether class which transform into unmonitored terminal PFAS 47 . Furthermore, there is no standardized TOP assay method, and results from the variants available can differ greatly, with too harsh conditions leading to mineralization of terminal target PFAS 48 . These findings suggest that TOP assay results may underrepresent future PFASʼ environmental burden. Given the relatively limited suite of PFAS that have been quantified in surface and groundwater, it is not possible to reliably discuss the extent to which current PFAS methods adequately capture the range of PFAS and mass in these systems.

Overall, this study suggests that a large fraction of surface and groundwaters globally exceed PFAS international advisories and regulations and that future PFAS environmental burden is likely underestimated. Because PFAS definition continues to evolve, the extent of underestimation will be a function of PFAS definition. Additional work is needed to develop analytical techniques to quantify PFAS in environmental matrices, conduct a more systematic sampling regime of water sources globally and quantify human and ecological impacts of the broad range of PFAS in the environment.

This study reviewed and collated 48,985 samples from 367 published papers and government websites to build a comprehensive database to determine PFAS global distribution in surface and groundwater (Supplementary Table 4 ). This study is therefore limited to PFAS tested in previous studies, the analytical instruments and methods used and the locations that were sampled. The data were collated, compared and analysed and statistically validated using Python scripts and MS Excel.

PFAS is reported in ng l −1 for aqueous concentrations. When investigating PFAS concentrations in products, all data were converted to parts per billion (ppb) using appropriate area to mass conversions as the data include PFAS from an array of sources in different compartments and measured with different instruments and sample-preparation techniques.

The data available were converted into an Excel file using an online open-source portable document format converter when required. All data was then saved as a comma-separated values or Microsoft Excel spreadsheet document before analysis with Python. To check the data, an initial screening was done using a Python script, followed by manual checks. When analytes were reported as below detection limits (BDL) or not detected, a random value between 0 and the detection limit was assigned using a loop in Python and the detection limit provided in each study. Even though there are specific statistical methods for handling censored data, they assume a specific data distribution not applicable in this case and as there are less than 60% of samples below the detection limit, substitution was suitable 49 . Randomizing the substitution reduces clustering of data around a specific value and biasing of results. To represent data on a map, the latitude and longitude of the sampling location was used. Where no location was specified other than the country, a random major city in that country was assigned to capture the sample’s location.

A list of the PFAS analytes, their major PFAS class and fluorinated chain length are included in Supplementary Table 1 . The PFAS classes considered include those that form as terminal products, that is, perfluorocarboxylates (PFCA), perfluorosulfonates (PFSA) and precursors to these terminal products. Precursors included are fluorotelomers, sulfonamides and polyfluorinated alkyl phosphate esters (PAPs). Within the fluorotelomer PFAS class subclasses include: alcohols (FTOH), sulfonates (FTS), iodides, n:2 saturated/unsaturated carboxylates (FTCA/FTUCA), acrylates and betaines. Finally, novel PFAS (which predominantly encapsulate the ether PFAS sub-group) were considered.

Data availability

Sources of data used to compile the database are provided in Supplementary Table 4 . The data analysed and used to generate the figures and tables in this study are available in the following Zenodo data repository: https://doi.org/10.5281/zenodo.10616840 . Source data are provided with this paper.

Code availability

Python scripts used to summarize data will be provided upon request.

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Acknowledgements

The Australian Government Research Training Program (RTP) Scholarship is acknowledged for the provision of candidature funding for D.A.G. The funders had no role in study design, data collection and analysis, decision to publish or preparation of the manuscript. All other authors received no specific funding for this work.

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Contributions

Conceptualization: conceived by D.M.O. and refined by all authors. Methodology: D.A.G., D.G., A.M.J., T.C.G.K. and D.M.O. Data collection: D.A.G., D.G. and J.H. Data analysis: D.A.G., D.G., A.M.J., T.C.G.K. and D.M.O. Validation: D.A.G., D.G. and A.M.J. Supervision: A.M.J., M.J.L. and D.M.O. Writing: D.A.G., A.M.J. and D.M.O. with input from all authors.

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Extended data

Extended data fig. 1 cumulative distribution of surface water samples from an unknown source that exceed a given pfas concentration..

Circles indicate relevant PFAS drinking water guidance values. For samples where PFAS concentrations were below detection limits a PFAS concentration was randomly assigned between zero the detection limit.

Extended Data Fig. 2 Cumulative distribution of surface water samples from a known non AFFF source that exceed a given PFAS concentration.

Extended data fig. 3 cumulative distribution of surface water samples from a known afff source that exceed a given pfas concentration., extended data fig. 4 cumulative distribution of groundwater samples from an unknown source that exceed a given pfas concentration., extended data fig. 5 cumulative distribution of groundwater samples from a known non afff source that exceed a given pfas concentration., extended data fig. 6 cumulative distribution of groundwater samples from a known afff source that exceed a given pfas concentration., supplementary information, supplementary information.

Supplementary Tables 1–4 and Figs. 1–9.

Supplementary Data 1

Source data for Supplementary Figs. 1–9.

Source Data

Statistical source data for Figs. 1–4.

Source Data Extended Data

Statistical source data for Extended Data Figs. 1–6.

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Ackerman Grunfeld, D., Gilbert, D., Hou, J. et al. Underestimated burden of per- and polyfluoroalkyl substances in global surface waters and groundwaters. Nat. Geosci. 17 , 340–346 (2024). https://doi.org/10.1038/s41561-024-01402-8

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Issue Date : April 2024

DOI : https://doi.org/10.1038/s41561-024-01402-8

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April 10, 2024

The U.S. Environmental Protection Agency announced on April 10 the final National Primary Drinking Water Regulation (NPDWR) for six PFAS.

NGWA supported this drinking water PFAS standard in comments submitted to the EPA. While the drinking water standard doesn't pertain to residential water wells, NGWA recommends the millions of Americans using water wells as their daily source of water to test and treat their water well systems for PFAS.

The Association has published a position paper, PFAS: The Truth About Private Water Wells and also has “ PFAS and Private Well Owners: What You Need to Know ,” a two-page fact sheet that groundwater professionals can distribute to customers and others in their community concerned about PFAS.

“I applaud the passing of our nation’s first standard for PFAS as it will bring protection to our nation’s groundwater resources,” said NGWA CEO Terry S. Morse, CAE, CIC. “PFAS contamination affects all communities and impacts our environment and our health. This is an important day. Millions of people rely on water wells every day, and NGWA and its members will help ensure these groundwater sources are safe for years to come.”

The EPA is making unprecedented funding available to help ensure that all people have clean and safe water. In addition to the final rule, $1 billion in newly available finding through the Bipartisan Infrastructure Law will help states and territories implement PFAS testing and treatment at public water systems and to help owners of private wells address PFAS contamination.

“At these extremely low levels, the financial and technical support provided by the EPA and other governmental agencies will be critical to the ability of the nation’s more than 40 million private well owners to test, and as needed, effectively treat their water supply,” said NGWA Director of Science and Technology Bill Alley, Ph.D.

The EPA finalized a National Primary Drinking Water Regulation (NPDWR) establishing legally enforceable levels, Maximum Contaminant Levels (MCLs), for six PFAS in drinking water. PFOA, PFOS, PFHxS, PFNA, and HFPO-DA as contaminants with individual MCLs, and PFAS mixtures containing at least two or more of PFHxS, PFNA, HFPO-DA, and PFBS using a Hazard Index MCL to account for the combined and co-occurring levels of these PFAS in drinking water. The EPA also finalized health-based, non-enforceable Maximum Contaminant Level Goals (MCLGs) for these PFAS.

For PFOA and PFOS, the EPA is setting MCLG, a non-enforceable health-based goal, at zero. This reflects the latest science showing that there is no level of exposure to these contaminants without risk of health impacts, including certain cancers.
The EPA is setting enforceable MCLs at 4.0 parts per trillion for PFOA and PFOS individually. This standard will reduce exposure from these PFAS in drinking water to the lowest levels that are feasible for effective implementation.
For PFNA, PFHxS, and “GenX Chemicals,” the EPA is setting the MCLGs and MCLs at 10 parts per trillion.
Because PFAS can often be found together in mixtures, and research shows these mixtures may have combined health impacts, the EPA is also setting a limit for any mixture of two or more of the following PFAS: PFNA, PFHxS, PFBS, and “GenX Chemicals.”

The final rule requires:

Public water systems must monitor for these PFAS and have three years to complete initial monitoring (by 2027), followed by ongoing compliance monitoring. Water systems must also provide the public with information on the levels of these PFAS in their drinking water beginning in 2027.
Public water systems have five years (by 2029) to implement solutions that reduce these PFAS if monitoring shows that drinking water levels exceed these MCLs.
Beginning in five years (2029), public water systems that have PFAS in drinking water which violates one or more of these MCLs must take action to reduce levels of these PFAS in their drinking water and must provide notification to the public of the violation.

Click here to read more .

NGWA has long been an industry leader in providing PFAS research, education, and resources to the public and scientific communities. Learn more by visiting NGWA.org/PFAS , which is a complete resource center about the groundwater contaminants featuring a recently updated top-10 facts sheet, a position paper, and more.

The Association is hosting, Groundwater in the PFAS Era: Stressors, Protection, and Compliance Conference , April 16-17 in Tucson, Arizona. Click here to learn more .

“NGWA and its membership have spent a tremendous amount of time and resources advocating for a national PFAS standard in Washington, D.C.,” Morse said. “Today, we finally see the results of those efforts and are one step closer to a level playing field for our industry and more importantly, cleaner and safer water for all Americans. There is still a lot of work to do, but I applaud all of those who worked so hard over the years to make this new national standard a reality.”

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PFAS ‘Forever Chemicals’ Are Pervasive in Water Worldwide, Study Finds

A global survey found harmful levels even in water samples taken far any obvious source of contamination.

A person wearing purple protective gloves and a lab coat pours water into a brown vial.

By Delger Erdenesanaa

They’re in makeup, dental floss and menstrual products. They’re in nonstick pans and takeout food wrappers . Same with rain jackets and firefighting equipment, as well as pesticides and artificial turf on sports fields.

They’re PFAS: a class of man-made chemicals called per- and polyfluoroalkyl substances. They are also called “forever chemicals” because the bonds in their chemical compounds are so strong they don’t break down for hundreds to thousands of years, if at all.

They’re also in our water.

A new study of more than 45,000 water samples around the world found that about 31 percent of groundwater samples tested that weren’t near any obvious source of contamination had PFAS levels considered harmful to human health by the Environmental Protection Agency.

About 16 percent of surface water samples tested, which were also not near any known source, had similarly hazardous PFAS levels.

This finding “sets off alarm bells,” said Denis O’Carroll, a professor of civil and environmental engineering at the University of New South Wales and one of the authors of the study, which was published on Monday in Nature Geoscience . “Not just for PFAS, but also for all the other chemicals that we put out into the environment. We don’t necessarily know their long-term impacts to us or the ecosystem.”

High levels of exposure to some PFAS chemicals have been linked to higher cholesterol, liver and immune system damage, hypertension and pre-eclampsia during pregnancy, as well as kidney and testicular cancer.

The E.P.A. has proposed strict new drinking water limits for six types of PFAS and could announce its final rule as early as this week.

For their research, Dr. O’Carroll and his colleagues gathered nearly 300 previously published studies on PFAS in the environment. Together, these studies included 12,000 samples from surface water — streams, rivers, ponds and lakes — and 33,900 samples from groundwater wells, collected over the past 20 years. These samples don’t cover the whole planet: they are concentrated in places with more environmental researchers, like the United States, Canada, Europe, Australia and the Pacific Coast of Asia.

The samples are probably also concentrated in places where people were already concerned about PFAS contamination, Dr. O’Carroll said. He cautioned that, as a result, the findings of this new study might be skewed to show higher levels of contamination than a true global average would. There’s reason to believe, however, that there’s some level of PFAS contamination nearly everywhere on the planet, he said.

Of the countries where studies had been done, the United States and Australia had particularly high concentrations of PFAS in their water samples.

Among the available samples, the highest levels of contamination were generally found near places like airports and military bases, which routinely use PFAS-containing foam to practice fighting fires. About 60 to 70 percent of both groundwater and surface water samples near these types of facilities had PFAS levels exceeding the E.P.A. Hazard Index , which measures how hazardous mixtures of certain chemicals might be to human health, and also exceeded limits in the E.P.A.’s proposed new drinking water regulations.

This research does an admirable job of collecting the available data and highlighting the extent of global contamination from PFAS chemicals, said David Andrews, a senior scientist at the Environmental Working Group, a research and advocacy organization, who was not involved in this study.

Scientific research on the health effects of PFAS has evolved significantly in the past 10 to 20 years, he said, and what are considered safe exposure levels now are a tiny fraction of what they were a few decades ago.

The proposed E.P.A. drinking water rules, depending on their final language, will be a big step forward, he said.

Michael Regan, the E.P.A. administrator, has said his agency intends to require utilities to treat their water so that levels of some PFAS are near zero . This requirement would make the United States one of the strictest countries in terms of regulating PFAS in water.

Dr. Andrews added, however, that while treating drinking water is important, it doesn’t solve the whole problem. His own research has shown that PFAS chemicals are pervasive in wildlife , too.

“Once they’re released into the environment, it’s incredibly difficult to clean them up, if not impossible in many cases,” he said. “They can be removed from drinking water, but the ultimate solution is to not use them in the first place, especially in places where there are clear alternatives.”

For example, some outdoor clothing brands are moving away from PFAS for waterproofing their products and toward alternatives like silicones. Fast food restaurants can wrap their burgers in paper that’s been treated with heat to make it grease-resistant, or coated in a PFAS-free plastic instead. The Department of Defense is beginning to replace traditional firefighting foam with an alternative called fluorine-free foam, or F3.

In the meantime, Dr. O’Carroll said, “I’m not in any way trying to say that we should not be drinking water.” He added, “It’s more that I’m trying to say, from a societal point of view, we need to be careful what we put into the environment.”

Delger Erdenesanaa is a reporter covering climate and the environment and a member of the 2023-24 Times Fellowship class, a program for journalists early in their careers. More about Delger Erdenesanaa

The Proliferation of ‘Forever Chemicals’

Pfas, or per- and polyfluoroalkyl substances, are hazardous compounds that pose a global threat to human health..

For the first time, the U.S. government is requiring municipal water systems to detect and remove PFAS from drinking water .

A global study found harmful levels of PFAS in water samples taken far from any obvious source of contamination.

Virtually indestructible, PFAS are used in fast-food packaging and countless household items .

PFAS lurk in much of what we eat, drink and use, but scientists are only beginning to understand how they affect our health .

Though no one can avoid forever chemicals entirely, Wirecutter offers tips on how to limit your exposure .

Scientists have spent years searching for ways to destroy forever chemicals. In 2022, a team of chemists found a cheap, effective method to break them down .

‘Forever chemicals’ are found in water sources around New Mexico, studies find

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So-called forever chemicals have been found in water sources across New Mexico, according to recent studies by the U.S. Geological Survey and state environment officials.

The federal agency detailed the findings Wednesday, the same day the U.S. Environmental Protection Agency announced its first-ever limits for several common types of PFAS, or perfluoroalkyl and polyfluoroalkyl substances.

Used in everyday products from nonstick pans and firefighting foam to waterproof clothing, PFAS have been linked to cancer and other health problems in humans. They are known as forever chemicals because they don’t degrade in the environment and remain in the bloodstream.

The research in New Mexico detected PFAS in all major rivers in the arid state, with the highest concentrations downstream of urban areas.

USGS researchers looked more closely at water quality in the Rio Grande as it flows through Albuquerque, New Mexico’s largest city, and found PFAS levels downstream that were about 10 times higher than at upstream locations.

Dozens of samples also were taken from groundwater wells and surface water sites as part of an initial statewide survey between August 2020 and October 2021, with officials saying the majority of wells sampled did not turn up PFAS. The work began after contamination was discovered at military installations.

Andy Jochems of the Environment Department’s water protection team said the latest findings will be helpful as regulators make decisions about protecting drinking water resources in the future.

Kimberly Beisner, a USGS hydrologist and lead author of the studies, said the work highlights the complex nature of chemicals in urban areas and their effects on river systems. She noted that concentrations near cities are constantly changing due to wastewater discharges and stormwater runoff, for example.

The utility that serves the Albuquerque area has not seen any PFAS concentrations in the drinking water system approaching the EPA limits, so officials said Wednesday they aren’t anticipating that the new regulations will require any action other than continued monitoring and reporting.

As for contaminants from Albuquerque going into the Rio Grande, utility spokesman David Morris said it’s possible that at some point there may need to be enhancements at the city’s sewage treatment plant.

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Groundwater: Origin, Sources and Other Details (with diagram)
Origin of Groundwater: Total water existing on earth is 13, 84,12,0000 cubic kms, out of which 8,00,0042 cubic kms is groundwater. Apart from this, 61,234 cubic kms is in form of soil moisture. Groundwater and soil moisture together constitute the sub-surface quantity of water.
Groundwater: Making the invisible visible in 2022 and beyond
Groundwater provides almost half of all drinking water worldwide, around 40% of the water used in irrigation and about one third of the supply required for industry. Not only does groundwater sustain ecosystems, it is also an important factor in climate change adaption. With the rise in water scarcity and the decrease in the availability of surface water (due to human activity and climate ...
The Importance of Groundwater
Groundwater and Humanity. Groundwater is a vital water supply for humanity. Groundwater provides drinking water entirely or in part for as much as 50% of the global population and accounts for 43% of all of water used for irrigation. Worldwide, 2.5 billion people depend solely on groundwater resources to satisfy their basic daily water needs.
Groundwater Basics
This Ground Water Atlas of the United States is a series of USGS publications that describe the location, the extent, and the geologic and hydrologic characteristics of the important aquifers of the Nation. The series consists of 13 chapters that describe the regional groundwater resources that collectively cover 50 States, Puerto Rico, and the ...
Groundwater
Groundwater Use in the United States. Groundwater is one of our most valuable resource—even though you probably never see it or even realize it is there. Groundwater is essential for irrigation and human use in many parts of the country. The use of groundwater in the United States in 2015 is described below. June 11, 2018.
(PDF) Groundwater
Groundwater consists. both of water that remains in the unsaturated or. vadose zone (also often termed "soil water") and. of water that reaches the saturated zone (aquifer) where pore spaces ...
Water Q&A: How important is groundwater? Completed
View Media Details. Groundwater, which is in aquifers below the surface of the Earth, is one of the Nation's most important natural resources. Groundwater is the source of about 33 percent of the water that county and city water departments supply to households and businesses (public supply). It provides drinking water for more than 90 percent ...
Groundwater and climate change: threats and opportunities
Climate change, and global change as a whole, underscores the urgency of looking forward and anticipating the role and importance of groundwater in climate adaptation. This essay shows that despite the many threats that need to be addressed, there are also clear opportunities to promote, by increasing aquifer recharge and storage, preserving ...
Global water resources and the role of groundwater in a ...
Water is a critical resource, but ensuring its availability faces challenges from climate extremes and human intervention. In this Review, we evaluate the current and historical evolution of water ...
Essay on Importance Of Groundwater
250 Words Essay on Importance Of Groundwater What is Groundwater? Groundwater is the water that soaks into the ground and collects in spaces between rocks and soil. It is a hidden treasure that helps keep our rivers, lakes, and wells filled with water. Imagine it as a giant underground lake that we can't see. Drinking and Cooking
Ground Water: Essay on Ground Water
Essay # 1. Introduction to Ground Water: Most of the water that infiltrates into the soil travels down to recharge the vast ground water stored at a depth within the earth. In fact, the ground water reserve is actually a huge source of fresh water and is many times that of surface water.
Groundwater quality: Global threats, opportunities and realising the
1. Introduction. Groundwater is the largest freshwater store on earth, its use underpins a huge range of human activities as well as important ecosystems (Margat and Van der Gun, 2013; Rohde et al., 2017).Historically, groundwater quantity has often been the focus of groundwater resource assessments, and there is a real need to now focus more attention towards groundwater quality.
Groundwater Salinity—Impacts and Possible Remedial Measures and
Continuous monitoring of the saline water interface is required to calculate the most effective management technique. The following possible remedial measures of saline water are suggested: 1. Maintaining a high basin water level. 2. Creating a freshwater bubble in a saline aquifer. 3.
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Dr. Richey is a postdoctoral associate at Washington State University in Pullman working on groundwater sustainability. In 2015 she published papers on annual change in groundwater storage from 2003 to 2013 in the 37 largest aquifer systems in the world.
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Groundwater® is the leading international journal focused exclusively on groundwater.Since 1963, Groundwater has published a dynamic mix of papers on topics related to groundwater including groundwater flow and well hydraulics, hydrogeochemistry and contaminant hydrogeology, application of geophysics, groundwater management and policy, and history of groundwater hydrology.
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Groundwater Recharge. Groundwater recharge is also known as deep percolation or deep drainage. It undergoes the hydrologic process, which moves surface water to groundwater. It is a primary method where water enters an aquifer. The recharge occurs at plant roots and is often known as a flux to the water table surface.
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Groundwater is the leading international journal focused exclusively on groundwater.Founded in 1963, it publishes a dynamic mix of papers on topics including groundwater flow and well hydraulics, hydrogeochemistry and contaminant hydrogeology, application of geophysics, groundwater management and policy, and history of groundwater hydrology.
Surface Water And Groundwater
The water on the Earth's surface - surface water - occurs as streams, lakes, rivers as well as bays and wetlands. The water below the surface of the Earth primarily is ground water, but it also includes soil water (Sphocleous, 2000). Interactions between groundwater and surface water play a critical role in the functioning of riparian ...
Protecting Our Groundwater: A Priority for a Sustainable Future
Groundwater depletion in India is a major concern because it is the primary source of drinking water. Some of the main causes of groundwater depletion in India include over-extraction of groundwater for irrigation, urbanisation, and climate change.. According to the Central Ground Water Board (CGWB) of India, approximately 70% of the total water used in India is from groundwater sources.
America Is Using Up Its Groundwater Like There's No Tomorrow
Overuse is draining and damaging aquifers nationwide, a New York Times data investigation revealed. A wealth of underground water helped create America, its vast cities and bountiful farmland. Now ...
Five Takeaways From Our Investigation Into America's Groundwater Crisis
Aug. 29, 2023. A New York Times investigation has found that America is depleting its invaluable reserves of groundwater at a dangerous rate. The practice of overpumping water from vast aquifers ...
Groundwater
Always submit the image at its final size. For Groundwater, that is 8.25 cm wide for one-column art and 17.15 cm wide for two-column art. Generate the image at line screens of 85 lines per inch (lpi) or lower. When applying multiple shades of gray, differentiate the gray levels by at least 20 percent.
Underestimated burden of per- and polyfluoroalkyl substances ...
This study reviewed and collated 48,985 samples from 367 published papers and government websites to build a comprehensive database to determine PFAS global distribution in surface and groundwater ...
EPA finalizes first drinking water standard for PFAS
The U.S. Environmental Protection Agency announced on April 10 the final National Primary Drinking Water Regulation (NPDWR) for six PFAS.. NGWA supported this drinking water PFAS standard in comments submitted to the EPA. While the drinking water standard doesn't pertain to residential water wells, NGWA recommends the millions of Americans using water wells as their daily source of water to ...
PFAS 'Forever Chemicals' Are Pervasive in Water Worldwide, Study Finds
Together, these studies included 12,000 samples from surface water — streams, rivers, ponds and lakes — and 33,900 samples from groundwater wells, collected over the past 20 years.
'Forever chemicals' are found in water sources around New Mexico
ALBUQUERQUE, N.M. — So-called forever chemicals have been found in water sources across New Mexico, according to recent studies by the U.S. Geological Survey and state environment officials.