dissertation on vaping

• Open access
• Published: 18 May 2021

An updated overview of e-cigarette impact on human health

• Patrice Marques   ORCID: orcid.org/0000-0003-0465-1727 1 , 2 ,
• Laura Piqueras   ORCID: orcid.org/0000-0001-8010-5168 1 , 2 , 3 &
• Maria-Jesus Sanz   ORCID: orcid.org/0000-0002-8885-294X 1 , 2 , 3  

Respiratory Research volume  22 , Article number:  151 ( 2021 ) Cite this article

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The electronic cigarette ( e-cigarette ), for many considered as a safe alternative to conventional cigarettes, has revolutionised the tobacco industry in the last decades. In e-cigarettes , tobacco combustion is replaced by e-liquid heating, leading some manufacturers to propose that e-cigarettes have less harmful respiratory effects than tobacco consumption. Other innovative features such as the adjustment of nicotine content and the choice of pleasant flavours have won over many users. Nevertheless, the safety of e-cigarette consumption and its potential as a smoking cessation method remain controversial due to limited evidence. Moreover, it has been reported that the heating process itself can lead to the formation of new decomposition compounds of questionable toxicity. Numerous in vivo and in vitro studies have been performed to better understand the impact of these new inhalable compounds on human health. Results of toxicological analyses suggest that e-cigarettes can be safer than conventional cigarettes, although harmful effects from short-term e-cigarette use have been described. Worryingly, the potential long-term effects of e-cigarette consumption have been scarcely investigated. In this review, we take stock of the main findings in this field and their consequences for human health including coronavirus disease 2019 (COVID-19).

Electronic nicotine dispensing systems (ENDS), commonly known as electronic cigarettes or e-cigarettes , have been popularly considered a less harmful alternative to conventional cigarette smoking since they first appeared on the market more than a decade ago. E-cigarettes are electronic devices, essentially consisting of a cartridge, filled with an e-liquid, a heating element/atomiser necessary to heat the e-liquid to create a vapour that can be inhaled through a mouthpiece, and a rechargeable battery (Fig.  1 ) [ 1 , 2 ]. Both the electronic devices and the different e-liquids are easily available in shops or online stores.

Effect of the heating process on aerosol composition. Main harmful effects documented. Several compounds detected in e-cigarette aerosols are not present in e-liquid s and the device material also seems to contribute to the presence of metal and silicate particles in the aerosols. The heating conditions especially on humectants, flavourings and the low-quality material used have been identified as the generator of the new compounds in aerosols. Some compounds generated from humectants (propylene glycol and glycerol) and flavourings, have been associated with clear airways impact, inflammation, impairment of cardiovascular function and toxicity. In addition, some of them are carcinogens or potential carcinogens

The e-liquid typically contains humectants and flavourings, with or without nicotine; once vapourised by the atomiser, the aerosol (vapour) provides a sensation similar to tobacco smoking, but purportedly without harmful effects [ 3 ]. However, it has been reported that the heating process can lead to the generation of new decomposition compounds that may be hazardous [ 4 , 5 ]. The levels of nicotine, which is the key addictive component of tobacco, can also vary between the commercially available e-liquids, and even nicotine-free options are available. For this particular reason, e-cigarettes are often viewed as a smoking cessation tool, given that those with nicotine can prevent smoking craving, yet this idea has not been fully demonstrated [ 2 , 6 , 7 ].

Because e-cigarettes are combustion-free, and because most of the damaging and well-known effects of tobacco are derived from this reaction, there is a common and widely spread assumption that e-cigarette consumption or “vaping” is safer than conventional cigarette smoking. However, are they risk-free? Is there sufficient toxicological data on all the components employed in e-liquids ? Do we really know the composition of the inhaled vapour during the heating process and its impact on health? Can e-cigarettes be used to curb tobacco use? Do their consumption impact on coronavirus disease 2019 (COVID-19)? In the present review, we have attempted to clarify these questions based on the existing scientific literature, and we have compiled new insights related with the toxicity derived from the use of these devices.

Effect of e-cigarette vapour versus conventional cigarette exposure: in vivo and in vitro effects

Numerous studies have been performed to evaluate the safety/toxicity of e-cigarette use both in vivo and in in vitro cell culture.

One of the first studies in humans involved the analysis of 9 volunteers that consumed e-cigarettes , with or without nicotine, in a ventilated room for 2 h [ 8 ]. Pollutants in indoor air, exhaled nitric oxide (NO) and urinary metabolite profiles were analysed. The results of this acute experiment revealed that e-cigarettes are not emission-free, and ultrafine particles formed from propylene glycol (PG) could be detected in the lungs. The study also suggested that the presence of nicotine in e-cigarettes increased the levels of NO exhaled from consumers and provoked marked airway inflammation; however, no differences were found in the levels of exhaled carbon monoxide (CO), an oxidative stress marker, before and after e-cigarette consumption [ 8 ]. A more recent human study detected significantly higher levels of metabolites of hazardous compounds including benzene, ethylene oxide, acrylonitrile, acrolein and acrylamide in the urine of adolescent dual users ( e-cigarettes and conventional tobacco consumers) than in adolescent e-cigarette -only users (Table 1 ) [ 9 ]. Moreover, the urine levels of metabolites of acrylonitrile, acrolein, propylene oxide, acrylamide and crotonaldehyde, all of which are detrimental for human health, were significantly higher in e-cigarette -only users than in non-smoker controls, reaching up to twice the registered values of those from non-smoker subjects (Table 1 ) [ 9 ]. In line with these observations, dysregulation of lung homeostasis has been documented in non-smokers subjected to acute inhalation of e-cigarette aerosols [ 10 ].

Little is known about the effect of vaping on the immune system. Interestingly, both traditional and e-cigarette consumption by non-smokers was found to provoke short-term effects on platelet function, increasing platelet activation (levels of soluble CD40 ligand and the adhesion molecule P-selectin) and platelet aggregation, although to a lesser extent with e-cigarettes [ 11 ]. As found with platelets, the exposure of neutrophils to e-cigarette aerosol resulted in increased CD11b and CD66b expression being both markers of neutrophil activation [ 12 ]. Additionally, increased oxidative stress, vascular endothelial damage, impaired endothelial function, and changes in vascular tone have all been reported in different human studies on vaping [ 13 , 14 , 15 , 16 , 17 ]. In this context, it is widely accepted that platelet and leukocyte activation as well as endothelial dysfunction are associated with atherogenesis and cardiovascular morbidity [ 18 , 19 ]. In line with these observations the potential association of daily e-cigarettes consumption and the increased risk of myocardial infarction remains controversial but benefits may occur when switching from tobacco to chronic e-cigarette use in blood pressure regulation, endothelial function and vascular stiffness (reviewed in [ 20 ]). Nevertheless, whether or not e-cigarette vaping has cardiovascular consequences requires further investigation.

More recently, in August 2019, the US Centers for Disease Control and Prevention (CDC) declared an outbreak of the e-cigarette or vaping product use-associated lung injury (EVALI) which caused several deaths in young population (reviewed in [ 20 ]). Indeed, computed tomography (CT scan) revealed local inflammation that impaired gas exchange caused by aerosolised oils from e-cigarettes [ 21 ]. However, most of the reported cases of lung injury were associated with use of e-cigarettes for tetrahydrocannabinol (THC) consumption as well as vitamin E additives [ 20 ] and not necessarily attributable to other e-cigarette components.

On the other hand, in a comparative study of mice subjected to either lab air, e-cigarette aerosol or cigarette smoke (CS) for 3 days (6 h-exposure per day), those exposed to e-cigarette aerosols showed significant increases in interleukin (IL)-6 but normal lung parenchyma with no evidence of apoptotic activity or elevations in IL-1β or tumour necrosis factor-α (TNFα) [ 22 ]. By contrast, animals exposed to CS showed lung inflammatory cell infiltration and elevations in inflammatory marker expression such as IL-6, IL-1β and TNFα [ 22 ]. Beyond airway disease, exposure to aerosols from e-liquids with or without nicotine has also been also associated with neurotoxicity in an early-life murine model [ 23 ].

Results from in vitro studies are in general agreement with the limited number of in vivo studies. For example, in an analysis using primary human umbilical vein endothelial cells (HUVEC) exposed to 11 commercially-available vapours, 5 were found to be acutely cytotoxic, and only 3 of those contained nicotine [ 24 ]. In addition, 5 of the 11 vapours tested (including 4 that were cytotoxic) reduced HUVEC proliferation and one of them increased the production of intracellular reactive oxygen species (ROS) [ 24 ]. Three of the most cytotoxic vapours—with effects similar to those of conventional high-nicotine CS extracts—also caused comparable morphological changes [ 24 ]. Endothelial cell migration is an important mechanism of vascular repair than can be disrupted in smokers due to endothelial dysfunction [ 25 , 26 ]. In a comparative study of CS and e-cigarette aerosols, Taylor et al . found that exposure of HUVEC to e-cigarette aqueous extracts for 20 h did not affect migration in a scratch wound assay [ 27 ], whereas equivalent cells exposed to CS extract showed a significant inhibition in migration that was concentration dependent [ 27 ].

In cultured human airway epithelial cells, both e-cigarette aerosol and CS extract induced IL-8/CXCL8 (neutrophil chemoattractant) release [ 28 ]. In contrast, while CS extract reduced epithelial barrier integrity (determined by the translocation of dextran from the apical to the basolateral side of the cell layer), e-cigarette aerosol did not, suggesting that only CS extract negatively affected host defence [ 28 ]. Moreover, Higham et al . also found that e-cigarette aerosol caused IL-8/CXCL8 and matrix metallopeptidase 9 (MMP-9) release together with enhanced activity of elastase from neutrophils [ 12 ] which might facilitate neutrophil migration to the site of inflammation [ 12 ].

In a comparative study, repeated exposure of human gingival fibroblasts to CS condensate or to nicotine-rich or nicotine-free e-vapour condensates led to alterations in morphology, suppression of proliferation and induction of apoptosis, with changes in all three parameters greater in cells exposed to CS condensate [ 29 ]. Likewise, both e-cigarette aerosol and CS extract increased cell death in adenocarcinomic human alveolar basal epithelial cells (A549 cells), and again the effect was more damaging with CS extract than with e-cigarette aerosol (detrimental effects found at 2 mg/mL of CS extract vs. 64 mg/mL of e-cigarette extract) [ 22 ], which is in agreement with another study examining battery output voltage and cytotoxicity [ 30 ].

All this evidence would suggest that e-cigarettes are potentially less harmful than conventional cigarettes (Fig.  2 ) [ 11 , 14 , 22 , 24 , 27 , 28 , 29 ]. Importantly, however, most of these studies have investigated only short-term effects [ 10 , 14 , 15 , 22 , 27 , 28 , 29 , 31 , 32 ], and the long-term effects of e-cigarette consumption on human health are still unclear and require further study.

Comparison of the degree of harmful effects documented from e-cigarette and conventional cigarette consumption. Human studies, in vivo mice exposure and in vitro studies. All of these effects from e-cigarettes were documented to be lower than those exerted by conventional cigarettes, which may suggest that e-cigarette consumption could be a safer option than conventional tobacco smoking but not a clear safe choice

Consequences of nicotine content

Beyond flavour, one of the major issues in the e-liquid market is the range of nicotine content available. Depending on the manufacturer, the concentration of this alkaloid can be presented as low , medium or high , or expressed as mg/mL or as a percentage (% v/v). The concentrations range from 0 (0%, nicotine-free option) to 20 mg/mL (2.0%)—the maximum nicotine threshold according to directive 2014/40/EU of the European Parliament and the European Union Council [ 33 , 34 ]. Despite this normative, however, some commercial e-liquids have nicotine concentrations close to 54 mg/mL [ 35 ], much higher than the limits established by the European Union.

The mislabelling of nicotine content in e-liquids has been previously addressed [ 8 , 34 ]. For instance, gas chromatography with a flame ionisation detector (GC-FID) revealed inconsistencies in the nicotine content with respect to the manufacturer´s declaration (average of 22 ± 0.8 mg/mL vs. 18 mg/mL) [ 8 ], which equates to a content ~ 22% higher than that indicated in the product label. Of note, several studies have detected nicotine in those e-liquids labelled as nicotine-free [ 5 , 35 , 36 ]. One study detected the presence of nicotine (0.11–6.90 mg/mL) in 5 of 23 nicotine-free labelled e-liquids by nuclear magnetic resonance spectroscopy [ 35 ], and another study found nicotine (average 8.9 mg/mL) in 13.6% (17/125) of the nicotine-free e-liquids as analysed by high performance liquid chromatography (HPLC) [ 36 ]. Among the 17 samples tested in this latter study 14 were identified to be counterfeit or suspected counterfeit. A third study detected nicotine in 7 of 10 nicotine-free refills, although the concentrations were lower than those identified in the previous analyses (0.1–15 µg/mL) [ 5 ]. Not only is there evidence of mislabelling of nicotine content among refills labelled as nicotine-free, but there also seems to be a history of poor labelling accuracy in nicotine-containing e-liquids [ 37 , 38 ].

A comparison of the serum levels of nicotine from e-cigarette or conventional cigarette consumption has been recently reported [ 39 ]. Participants took one vape from an e-cigarette , with at least 12 mg/mL of nicotine, or inhaled a conventional cigarette, every 20 s for 10 min. Blood samples were collected 1, 2, 4, 6, 8, 10, 12 and 15 min after the first puff, and nicotine serum levels were measured by liquid chromatography-mass spectrometry (LC–MS). The results revealed higher serum levels of nicotine in the conventional CS group than in the e-cigarette group (25.9 ± 16.7 ng/mL vs. 11.5 ± 9.8 ng/mL). However, e-cigarettes containing 20 mg/mL of nicotine are more equivalent to normal cigarettes, based on the delivery of approximately 1 mg of nicotine every 5 min [ 40 ].

In this line, a study compared the acute impact of CS vs. e-cigarette vaping with equivalent nicotine content in healthy smokers and non-smokers. Both increased markers of oxidative stress and decreased NO bioavailability, flow-mediated dilation, and vitamin E levels showing no significant differences between tobacco and e-cigarette exposure (reviewed in [ 20 ]). Inasmuch, short-term e-cigarette use in healthy smokers resulted in marked impairment of endothelial function and an increase in arterial stiffness (reviewed in [ 20 ]). Similar effects on endothelial dysfunction and arterial stiffness were found in animals when they were exposed to e-cigarette vapor either for several days or chronically (reviewed in [ 20 ]). In contrast, other studies found acute microvascular endothelial dysfunction, increased oxidative stress and arterial stiffness in smokers after exposure to e-cigarettes with nicotine, but not after e-cigarettes without nicotine (reviewed in [ 20 ]). In women smokers, a study found a significant difference in stiffness after smoking just one tobacco cigarette, but not after use of e-cigarettes (reviewed in [ 20 ]).

It is well known that nicotine is extremely addictive and has a multitude of harmful effects. Nicotine has significant biologic activity and adversely affects several physiological systems including the cardiovascular, respiratory, immunological and reproductive systems, and can also compromise lung and kidney function [ 41 ]. Recently, a sub-chronic whole-body exposure of e-liquid (2 h/day, 5 days/week, 30 days) containing PG alone or PG with nicotine (25 mg/mL) to wild type (WT) animals or knockout (KO) mice in α7 nicotinic acetylcholine receptor (nAChRα7-KO) revealed a partly nAChRα7-dependent lung inflammation [ 42 ]. While sub-chronic exposure to PG/nicotine promote nAChRα7-dependent increased levels of different cytokines and chemokines in the bronchoalveolar lavage fluid (BALF) such as IL-1α, IL-2, IL-9, interferon γ (IFNγ), granulocyte-macrophage colony-stimulating factor (GM-CSF), monocyte chemoattractant protein-1 (MCP-1/CCL2) and regulated on activation, normal T cell expressed and secreted (RANTES/CCL5), the enhanced levels of IL-1β, IL-5 and TNFα were nAChRα7 independent. In general, most of the cytokines detected in BALF were significantly increased in WT mice exposed to PG with nicotine compared to PG alone or air control [ 42 ]. Some of these effects were found to be through nicotine activation of NF-κB signalling albeit in females but not in males. In addition, PG with nicotine caused increased macrophage and CD4 + /CD8 + T-lymphocytes cell counts in BALF compared to air control, but these effects were ameliorated when animals were sub-chronically exposed to PG alone [ 42 ].

Of note, another study indicated that although RANTES/CCL5 and CCR1 mRNA were upregulated in flavour/nicotine-containing e-cigarette users, vaping flavour and nicotine-less e-cigarettes did not significantly dysregulate cytokine and inflammasome activation [ 43 ].

In addition to its toxicological effects on foetus development, nicotine can disrupt brain development in adolescents and young adults [ 44 , 45 , 46 ]. Several studies have also suggested that nicotine is potentially carcinogenic (reviewed in [ 41 ]), but more work is needed to prove its carcinogenicity independently of the combustion products of tobacco [ 47 ]. In this latter regard, no differences were encountered in the frequency of tumour appearance in rats subjected to long-term (2 years) inhalation of nicotine when compared with control rats [ 48 ]. Despite the lack of carcinogenicity evidence, it has been reported that nicotine promotes tumour cell survival by decreasing apoptosis and increasing proliferation [ 49 ], indicating that it may work as a “tumour enhancer”. In a very recent study, chronic administration of nicotine to mice (1 mg/kg every 3 days for a 60-day period) enhanced brain metastasis by skewing the polarity of M2 microglia, which increases metastatic tumour growth [ 50 ]. Assuming that a conventional cigarette contains 0.172–1.702 mg of nicotine [ 51 ], the daily nicotine dose administered to these animals corresponds to 40–400 cigarettes for a 70 kg-adult, which is a dose of an extremely heavy smoker. We would argue that further studies with chronic administration of low doses of nicotine are required to clearly evaluate its impact on carcinogenicity.

In the aforementioned study exposing human gingival fibroblasts to CS condensate or to nicotine-rich or nicotine-free e-vapour condensates [ 29 ], the detrimental effects were greater in cells exposed to nicotine-rich condensate than to nicotine-free condensate, suggesting that the possible injurious effects of nicotine should be considered when purchasing e-refills . It is also noteworthy that among the 3 most cytotoxic vapours for HUVEC evaluated in the Putzhammer et al . study, 2 were nicotine-free, which suggests that nicotine is not the only hazardous component in e-cigarettes [ 24 ] .

The lethal dose of nicotine for an adult is estimated at 30–60 mg [ 52 ]. Given that nicotine easily diffuses from the dermis to the bloodstream, acute nicotine exposure by e-liquid spilling (5 mL of a 20 mg/mL nicotine-containing refill is equivalent to 100 mg of nicotine) can easily be toxic or even deadly [ 8 ]. Thus, devices with rechargeable refills are another issue of concern with e-cigarettes , especially when e-liquids are not sold in child-safe containers, increasing the risk of spilling, swallowing or breathing.

These data overall indicate that the harmful effects of nicotine should not be underestimated. Despite the established regulations, some inaccuracies in nicotine content labelling remain in different brands of e-liquids . Consequently, stricter regulation and a higher quality control in the e-liquid industry are required.

Effect of humectants and their heating-related products

In this particular aspect, again the composition of the e-liquid varies significantly among different commercial brands [ 4 , 35 ]. The most common and major components of e-liquids are PG or 1,2-propanediol, and glycerol or glycerine (propane-1,2,3-triol). Both types of compounds are used as humectants to prevent the e-liquid from drying out [ 2 , 53 ] and are classified by the Food and Drug Administration (FDA) as “Generally Recognised as Safe” [ 54 ]. In fact, they are widely used as alimentary and pharmaceutical products [ 2 ]. In an analysis of 54 commercially available e-liquids , PG and glycerol were detected in almost all samples at concentrations ranging from 0.4% to 98% (average 57%) and from 0.3% to 95% (average 37%), respectively [ 35 ].

With regards to toxicity, little is known about the effects of humectants when they are heated and chronically inhaled. Studies have indicated that PG can induce respiratory irritation and increase the probability of asthma development [ 55 , 56 ], and both PG and glycerol from e-cigarettes might reach concentrations sufficiently high to potentially cause irritation of the airways [ 57 ]. Indeed, the latter study established that one e-cigarette puff results in a PG exposure of 430–603 mg/m 3 , which is higher than the levels reported to cause airway irritation (average 309 mg/m 3 ) based on a human study [ 55 ]. The same study established that one e-cigarette puff results in a glycerol exposure of 348–495 mg/m 3 [ 57 ], which is close to the levels reported to cause airway irritation in rats (662 mg/m 3 ) [ 58 ].

Airway epithelial injury induced by acute vaping of PG and glycerol aerosols (50:50 vol/vol), with or without nicotine, has been reported in two randomised clinical trials in young tobacco smokers [ 32 ]. In vitro, aerosols from glycerol only-containing refills showed cytotoxicity in A549 and human embryonic stem cells, even at a low battery output voltage [ 59 ]. PG was also found to affect early neurodevelopment in a zebrafish model [ 60 ]. Another important issue is that, under heating conditions PG can produce acetaldehyde or formaldehyde (119.2 or 143.7 ng/puff at 20 W, respectively, on average), while glycerol can also generate acrolein (53.0, 1000.0 or 5.9 ng/puff at 20 W, respectively, on average), all carbonyls with a well-documented toxicity [ 61 ]. Although, assuming 15 puffs per e-cigarette unit, carbonyls produced by PG or glycerol heating would be below the maximum levels found in a conventional cigarette combustion (Table 2 ) [ 51 , 62 ]. Nevertheless, further studies are required to properly test the deleterious effects of all these compounds at physiological doses resembling those to which individuals are chronically exposed.

Although PG and glycerol are the major components of e-liquids other components have been detected. When the aerosols of 4 commercially available e-liquids chosen from a top 10 list of “ Best E-Cigarettes of 2014” , were analysed by gas chromatography-mass spectrometry (GC–MS) after heating, numerous compounds were detected, with nearly half of them not previously identified [ 4 ], thus suggesting that the heating process per se generates new compounds of unknown consequence. Of note, the analysis identified formaldehyde, acetaldehyde and acrolein [ 4 ], 3 carbonyl compounds with known high toxicity [ 63 , 64 , 65 , 66 , 67 ]. While no information was given regarding formaldehyde and acetaldehyde concentrations, the authors calculated that one puff could result in an acrolein exposure of 0.003–0.015 μg/mL [ 4 ]. Assuming 40 mL per puff and 15 puffs per e-cigarette unit (according to several manufacturers) [ 4 ], each e-cigarette unit would generate approximately 1.8–9 μg of acrolein, which is less than the levels of acrolein emitted by a conventional tobacco cigarette (18.3–98.2 μg) [ 51 ]. However, given that e-cigarette units of vaping are not well established, users may puff intermittently throughout the whole day. Thus, assuming 400 to 500 puffs per cartridge, users could be exposed to up to 300 μg of acrolein.

In a similar study, acrolein was found in 11 of 12 aerosols tested, with a similar content range (approximately 0.07–4.19 μg per e-cigarette unit) [ 68 ]. In the same study, both formaldehyde and acetaldehyde were detected in all of the aerosols tested, with contents of 0.2–5.61 μg and 0.11–1.36 μg, respectively, per e-cigarette unit [ 68 ]. It is important to point out that the levels of these toxic products in e-cigarette aerosols are significantly lower than those found in CS: 9 times lower for formaldehyde, 450 times lower for acetaldehyde and 15 times lower for acrolein (Table 2 ) [ 62 , 68 ].

Other compounds that have been detected in aerosols include acetamide, a potential human carcinogen [ 5 ], and some aldehydes [ 69 ], although their levels were minimal. Interestingly, the existence of harmful concentrations of diethylene glycol, a known cytotoxic agent, in e-liquid aerosols is contentious with some studies detecting its presence [ 4 , 68 , 70 , 71 , 72 ], and others finding low subtoxic concentrations [ 73 , 74 ]. Similar observations were reported for the content ethylene glycol. In this regard, either it was detected at concentrations that did not exceed the authorised limit [ 73 ], or it was absent from the aerosols produced [ 4 , 71 , 72 ]. Only one study revealed its presence at high concentration in a very low number of samples [ 5 ]. Nevertheless, its presence above 1 mg/g is not allowed by the FDA [ 73 ]. Figure  1 lists the main compounds detected in aerosols derived from humectant heating and their potential damaging effects. It would seem that future studies should analyse the possible toxic effects of humectants and related products at concentrations similar to those that e-cigarette vapers are exposed to reach conclusive results.

Impact of flavouring compounds

The range of e-liquid flavours available to consumers is extensive and is used to attract both current smokers and new e-cigarette users, which is a growing public health concern [ 6 ]. In fact, over 5 million middle- and high-school students were current users of e-cigarettes in 2019 [ 75 ], and appealing flavours have been identified as the primary reason for e-cigarette consumption in 81% of young users [ 76 ]. Since 2016, the FDA regulates the flavours used in the e-cigarette market and has recently published an enforcement policy on unauthorised flavours, including fruit and mint flavours, which are more appealing to young users [ 77 ]. However, the long-term effects of all flavour chemicals used by this industry (which are more than 15,000) remain unknown and they are not usually included in the product label [ 78 ]. Furthermore, there is no safety guarantee since they may harbour potential toxic or irritating properties [ 5 ].

With regards to the multitude of available flavours, some have demonstrated cytotoxicity [ 59 , 79 ]. Bahl et al. evaluated the toxicity of 36 different e-liquids and 29 different flavours on human embryonic stem cells, mouse neural stem cells and human pulmonary fibroblasts using a metabolic activity assay. In general, those e-liquids that were bubblegum-, butterscotch- and caramel-flavoured did not show any overt cytotoxicity even at the highest dose tested. By contrast, those e-liquids with Freedom Smoke Menthol Arctic and Global Smoke Caramel flavours had marked cytotoxic effects on pulmonary fibroblasts and those with Cinnamon Ceylon flavour were the most cytotoxic in all cell lines [ 79 ]. A further study from the same group [ 80 ] revealed that high cytotoxicity is a recurrent feature of cinnamon-flavoured e-liquids. In this line, results from GC–MS and HPLC analyses indicated that cinnamaldehyde (CAD) and 2-methoxycinnamaldehyde, but not dipropylene glycol or vanillin, were mainly responsible for the high cytotoxicity of cinnamon-flavoured e-liquids [ 80 ]. Other flavouring-related compounds that are associated with respiratory complications [ 81 , 82 , 83 ], such as diacetyl, 2,3-pentanedione or acetoin, were found in 47 out of 51 aerosols of flavoured e-liquids tested [ 84 ] . Allen et al . calculated an average of 239 μg of diacetyl per cartridge [ 84 ]. Assuming again 400 puffs per cartridge and 40 mL per puff, is it is possible to estimate an average of 0.015 ppm of diacetyl per puff, which could compromise normal lung function in the long-term [ 85 ].

The cytotoxic and pro-inflammatory effects of different e-cigarette flavouring chemicals were also tested on two human monocytic cell lines—mono mac 6 (MM6) and U937 [ 86 ]. Among the flavouring chemicals tested, CAD was found to be the most toxic and O-vanillin and pentanedione also showed significant cytotoxicity; by contrast, acetoin, diacetyl, maltol, and coumarin did not show any toxicity at the concentrations assayed (10–1000 µM). Of interest, a higher toxicity was evident when combinations of different flavours or mixed equal proportions of e-liquids from 10 differently flavoured e-liquids were tested, suggesting that vaping a single flavour is less toxic than inhaling mixed flavours [ 86 ]. Also, all the tested flavours produced significant levels of ROS in a cell-free ROS production assay. Finally, diacetyl, pentanedione, O-vanillin, maltol, coumarin, and CAD induced significant IL-8 secretion from MM6 and U937 monocytes [ 86 ]. It should be borne in mind, however, that the concentrations assayed were in the supra-physiological range and it is likely that, once inhaled, these concentrations are not reached in the airway space. Indeed, one of the limitations of the study was that human cells are not exposed to e-liquids per se, but rather to the aerosols where the concentrations are lower [ 86 ]. In this line, the maximum concentration tested (1000 µM) would correspond to approximately 80 to 150 ppm, which is far higher than the levels found in aerosols of some of these compounds [ 84 ]. Moreover, on a day-to-day basis, lungs of e-cigarette users are not constantly exposed to these chemicals for 24 h at these concentrations. Similar limitations were found when five of seven flavourings were found to cause cytotoxicity in human bronchial epithelial cells [ 87 ].

Recently, a commonly commercialized crème brûlée -flavoured aerosol was found to contain high concentrations of benzoic acid (86.9 μg/puff), a well-established respiratory irritant [ 88 ]. When human lung epithelial cells (BEAS-2B and H292) were exposed to this aerosol for 1 h, a marked cytotoxicity was observed in BEAS-2B but not in H292 cells, 24 h later. However, increased ROS production was registered in H292 cells [ 88 ].

Therefore, to fully understand the effects of these compounds, it is relevant the cell cultures selected for performing these assays, as well as the use of in vivo models that mimic the real-life situation of chronic e-cigarette vapers to clarify their impact on human health.

The e-cigarette device

While the bulk of studies related to the impact of e-cigarette use on human health has focused on the e-liquid components and the resulting aerosols produced after heating, a few studies have addressed the material of the electronic device and its potential consequences—specifically, the potential presence of metals such as copper, nickel or silver particles in e-liquids and aerosols originating from the filaments and wires and the atomiser [ 89 , 90 , 91 ].

Other important components in the aerosols include silicate particles from the fiberglass wicks or silicone [ 89 , 90 , 91 ]. Many of these products are known to cause abnormalities in respiratory function and respiratory diseases [ 89 , 90 , 91 ], but more in-depth studies are required. Interestingly, the battery output voltage also seems to have an impact on the cytotoxicity of the aerosol vapours, with e-liquids from a higher battery output voltage showing more toxicity to A549 cells [ 30 ].

A recent study compared the acute effects of e-cigarette vapor (with PG/vegetable glycerine plus tobacco flavouring but without nicotine) generated from stainless‐steel atomizer (SS) heating element or from a nickel‐chromium alloy (NC) [ 92 ]. Some rats received a single e-cigarette exposure for 2 h from a NC heating element (60 or 70 W); other rats received a similar exposure of e-cigarette vapor using a SS heating element for the same period of time (60 or 70 W) and, a final group of animals were exposed for 2 h to air. Neither the air‐exposed rats nor those exposed to e-cigarette vapor using SS heating elements developed respiratory distress. In contrast, 80% of the rats exposed to e-cigarette vapor using NC heating units developed clinical acute respiratory distress when a 70‐W power setting was employed. Thus, suggesting that operating units at higher than recommended settings can cause adverse effects. Nevertheless, there is no doubt that the deleterious effects of battery output voltage are not comparable to those exerted by CS extracts [ 30 ] (Figs.  1 and 2 ).

E-cigarettes as a smoking cessation tool

CS contains a large number of substances—about 7000 different constituents in total, with sizes ranging from atoms to particulate matter, and with many hundreds likely responsible for the harmful effects of this habit [ 93 ]. Given that tobacco is being substituted in great part by e-cigarettes with different chemical compositions, manufacturers claim that e -cigarette will not cause lung diseases such as lung cancer, chronic obstructive pulmonary disease, or cardiovascular disorders often associated with conventional cigarette consumption [ 3 , 94 ]. However, the World Health Organisation suggests that e-cigarettes cannot be considered as a viable method to quit smoking, due to a lack of evidence [ 7 , 95 ]. Indeed, the results of studies addressing the use of e-cigarettes as a smoking cessation tool remain controversial [ 96 , 97 , 98 , 99 , 100 ]. Moreover, both FDA and CDC are actively investigating the incidence of severe respiratory symptoms associated with the use of vaping products [ 77 ]. Because many e-liquids contain nicotine, which is well known for its powerful addictive properties [ 41 ], e-cigarette users can easily switch to conventional cigarette smoking, avoiding smoking cessation. Nevertheless, the possibility of vaping nicotine-free e-cigarettes has led to the branding of these devices as smoking cessation tools [ 2 , 6 , 7 ].

In a recently published randomised trial of 886 subjects who were willing to quit smoking [ 100 ], the abstinence rate was found to be twice as high in the e-cigarette group than in the nicotine-replacement group (18.0% vs. 9.9%) after 1 year. Of note, the abstinence rate found in the nicotine-replacement group was lower than what is usually expected with this therapy. Nevertheless, the incidence of throat and mouth irritation was higher in the e-cigarette group than in the nicotine-replacement group (65.3% vs. 51.2%, respectively). Also, the participant adherence to the treatment after 1-year abstinence was significantly higher in the e-cigarette group (80%) than in nicotine-replacement products group (9%) [ 100 ].

On the other hand, it is estimated that COPD could become the third leading cause of death in 2030 [ 101 ]. Given that COPD is generally associated with smoking habits (approximately 15 to 20% of smokers develop COPD) [ 101 ], smoking cessation is imperative among COPD smokers. Published data revealed a clear reduction of conventional cigarette consumption in COPD smokers that switched to e-cigarettes [ 101 ]. Indeed, a significant reduction in exacerbations was observed and, consequently, the ability to perform physical activities was improved when data was compared with those non-vapers COPD smokers. Nevertheless, a longer follow-up of these COPD patients is required to find out whether they have quitted conventional smoking or even vaping, since the final goal under these circumstances is to quit both habits.

Based on the current literature, it seems that several factors have led to the success of e-cigarette use as a smoking cessation tool. First, some e-cigarette flavours positively affect smoking cessation outcomes among smokers [ 102 ]. Second, e-cigarettes have been described to improve smoking cessation rate only among highly-dependent smokers and not among conventional smokers, suggesting that the individual degree of nicotine dependence plays an important role in this process [ 97 ]. Third, the general belief of their relative harmfulness to consumers' health compared with conventional combustible tobacco [ 103 ]. And finally, the exposure to point-of-sale marketing of e-cigarette has also been identified to affect the smoking cessation success [ 96 ].

Implication of e-cigarette consumption in COVID-19 time

Different reports have pointed out that smokers and vapers are more vulnerable to SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2) infections or more prone to adverse outcomes if they suffer COVID-19 [ 104 ]. However, while a systematic review indicated that cigarette smoking is probably associated with enhanced damage from COVID-19, a meta-analysis did not, yet the latter had several limitations due to the small sample sizes [ 105 ].

Interestingly, most of these reports linking COVID-19 harmful effects with smoking or vaping, are based on their capability of increasing the expression of angiotensin-converting enzyme 2 (ACE2) in the lung. It is well known that ACE2 is the gate for SARS-CoV-2 entrance to the airways [ 106 ] and it is mainly expressed in type 2 alveolar epithelial cells and alveolar macrophages [ 107 ]. To date, most of the studies in this field indicate that current smokers have higher expression of ACE2 in the airways (reviewed by [ 108 ]) than healthy non-smokers [ 109 , 110 ]. However, while a recent report indicated that e-cigarette vaping also caused nicotine-dependent ACE2 up-regulation [ 42 ], others have revealed that neither acute inhalation of e-cigarette vapour nor e-cigarette users had increased lung ACE2 expression regardless nicotine presence in the e-liquid [ 43 , 110 ].

In regard to these contentions, current knowledge suggests that increased ACE2 expression is not necessarily linked to enhanced susceptibility to SARS-CoV-2 infection and adverse outcome. Indeed, elderly population express lower levels of ACE2 than young people and SARS-CoV-2/ACE2 interaction further decreases ACE2 expression. In fact, most of the deaths provoked by COVID-19 took place in people over 60 years old of age [ 111 ]. Therefore, it is plausible that the increased susceptibility to disease progression and the subsequent fatal outcome in this population is related to poor angiotensin 1-7 (Ang-1-7) generation, the main peptide generated by ACE2, and probably to their inaccessibility to its anti-inflammatory effects. Furthermore, it seems that all the efforts towards increasing ACE2 expression may result in a better resolution of the pneumonic process associated to this pandemic disease.

Nevertheless, additional complications associated to COVID-19 are increased thrombotic events and cytokine storm. In the lungs, e-cigarette consumption has been correlated to toxicity, oxidative stress, and inflammatory response [ 32 , 112 ]. More recently, a study revealed that while the use of nicotine/flavour-containing e-cigarettes led to significant cytokine dysregulation and potential inflammasome activation, none of these effects were detected in non-flavoured and non-nicotine-containing e-cigarettes [ 43 ]. Therefore, taken together these observations, e-cigarette use may still be a potent risk factor for severe COVID-19 development depending on the flavour and nicotine content.

In summary, it seems that either smoking or nicotine vaping may adversely impact on COVID-19 outcome. However, additional follow up studies are required in COVID-19 pandemic to clarify the effect of e-cigarette use on lung and cardiovascular complications derived from SARS-CoV-2 infection.

Conclusions

The harmful effects of CS and their deleterious consequences are both well recognised and widely investigated. However, and based on the studies carried out so far, it seems that e-cigarette consumption is less toxic than tobacco smoking. This does not necessarily mean, however, that e-cigarettes are free from hazardous effects. Indeed, studies investigating their long-term effects on human health are urgently required. In this regard, the main additional studies needed in this field are summarized in Table 3 .

The composition of e-liquids requires stricter regulation, as they can be easily bought online and many incidences of mislabelling have been detected, which can seriously affect consumers’ health. Beyond their unknown long-term effects on human health, the extended list of appealing flavours available seems to attract new “never-smokers”, which is especially worrying among young users. Additionally, there is still a lack of evidence of e-cigarette consumption as a smoking cessation method. Indeed, e-cigarettes containing nicotine may relieve the craving for smoking, but not the conventional cigarette smoking habit.

Interestingly, there is a strong difference of opinion on e-cigarettes between countries. Whereas countries such as Brazil, Uruguay and India have banned the sale of e-cigarettes , others such as the United Kingdom support this device to quit smoking. The increasing number of adolescent users and reported deaths in the United States prompted the government to ban the sale of flavoured e-cigarettes in 2020. The difference in opinion worldwide may be due to different restrictions imposed. For example, while no more than 20 ng/mL of nicotine is allowed in the EU, e-liquids with 59 mg/dL are currently available in the United States. Nevertheless, despite the national restrictions, users can easily access foreign or even counterfeit products online.

In regard to COVID-19 pandemic, the actual literature suggests that nicotine vaping may display adverse outcomes. Therefore, follow up studies are necessary to clarify the impact of e-cigarette consumption on human health in SARS-CoV-2 infection.

In conclusion, e-cigarettes could be a good alternative to conventional tobacco cigarettes, with less side effects; however, a stricter sale control, a proper regulation of the industry including flavour restriction, as well as further toxicological studies, including their chronic effects, are warranted.

Availability of data and materials

Not applicable.

Abbreviations

Angiotensin-converting enzyme 2

Angiotensin 1-7

Bronchoalveolar lavage fluid

Cinnamaldehyde

US Centers for Disease Control and Prevention

Carbon monoxide

Chronic obstructive pulmonary disease

Coronavirus disease 2019

Cigarette smoke

Electronic nicotine dispensing systems

e-cigarette or vaping product use-associated lung injury

Food and Drug Administration

Gas chromatography with a flame ionisation detector

Gas chromatography-mass spectrometry

Granulocyte–macrophage colony-stimulating factor

High performance liquid chromatography

Human umbilical vein endothelial cells

Interleukin

Interferon γ

Liquid chromatography-mass spectrometry

Monocyte chemoattractant protein-1

Matrix metallopeptidase 9

α7 Nicotinic acetylcholine receptor

Nickel‐chromium alloy

Nitric oxide

Propylene glycol

Regulated on activation, normal T cell expressed and secreted

Reactive oxygen species

Severe acute respiratory syndrome coronavirus 2

Stainless‐steel atomizer

Tetrahydrocannabinol

Tumour necrosis factor-α

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Acknowledgements

The authors gratefully acknowledge Dr. Cruz González, Pulmonologist at University Clinic Hospital of Valencia (Valencia, Spain) for her thoughtful suggestions and support.

This work was supported by the Spanish Ministry of Science and Innovation [Grant Number SAF2017-89714-R]; Carlos III Health Institute [Grant Numbers PIE15/00013, PI18/00209]; Generalitat Valenciana [Grant Number PROMETEO/2019/032, Gent T CDEI-04/20-A and AICO/2019/250], and the European Regional Development Fund.

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Marques, P., Piqueras, L. & Sanz, MJ. An updated overview of e-cigarette impact on human health. Respir Res 22 , 151 (2021). https://doi.org/10.1186/s12931-021-01737-5

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Impact of vaping on respiratory health

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Protecting children from harms of vaping

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• Andrea Jonas , clinical assistant professor
• Division of Pulmonary, Allergy, and Critical Care, Department of Medicine, Stanford University, Stanford, CA, USA
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Widespread uptake of vaping has signaled a sea change in the future of nicotine consumption. Vaping has grown in popularity over the past decade, in part propelled by innovations in vape pen design and nicotine flavoring. Teens and young adults have seen the biggest uptake in use of vape pens, which have superseded conventional cigarettes as the preferred modality of nicotine consumption. Relatively little is known, however, about the potential effects of chronic vaping on the respiratory system. Further, the role of vaping as a tool of smoking cessation and tobacco harm reduction remains controversial. The 2019 E-cigarette or Vaping Use-Associated Lung Injury (EVALI) outbreak highlighted the potential harms of vaping, and the consequences of long term use remain unknown. Here, we review the growing body of literature investigating the impacts of vaping on respiratory health. We review the clinical manifestations of vaping related lung injury, including the EVALI outbreak, as well as the effects of chronic vaping on respiratory health and covid-19 outcomes. We conclude that vaping is not without risk, and that further investigation is required to establish clear public policy guidance and regulation.

Abbreviations

BAL bronchoalveolar lavage

CBD cannabidiol

CDC Centers for Disease Control and Prevention

DLCO diffusing capacity of the lung for carbon monoxide

EMR electronic medical record

END electronic nicotine delivery systems

EVALI E-cigarette or Vaping product Use-Associated Lung Injury

LLM lipid laden macrophages

THC tetrahydrocannabinol

V/Q ventilation perfusion

Introduction

The introduction of vape pens to international markets in the mid 2000s signaled a sea change in the future of nicotine consumption. Long the mainstay of nicotine use, conventional cigarette smoking was on the decline for decades in the US, 1 2 largely owing to generational shifts in attitudes toward smoking. 3 With the advent of vape pens, trends in nicotine use have reversed, and the past two decades have seen a steady uptake of vaping among young, never smokers. 4 5 6 Vaping is now the preferred modality of nicotine consumption among young people, 7 and 2020 surveys indicate that one in five US high school students currently vape. 8 These trends are reflected internationally, where the prevalence of vape products has grown in both China and the UK. 9 Relatively little is known, however, regarding the health consequences of chronic vape pen use. 10 11 Although vaping was initially heralded as a safer alternative to cigarette smoking, 12 13 the toxic substances found in vape aerosols have raised new questions about the long term safety of vaping. 14 15 16 17 The 2019 E-cigarette or Vaping product Use-Associated Lung Injury (EVALI) outbreak, ultimately linked to vitamin E acetate in THC vapes, raised further concerns about the health effects of vaping, 18 19 20 and has led to increased scientific interest in the health consequences of chronic vaping. This review summarizes the history and epidemiology of vaping, and the clinical manifestations and proposed pathophysiology of lung injury caused by vaping. The public health consequences of widespread vaping remain to be seen and are compounded by young users of vape pens later transitioning to combustible cigarettes. 4 21 22 Deepened scientific understanding and public awareness of the potential harms of vaping are imperative to confront the challenges posed by a new generation of nicotine users.

Sources and selection criteria

We searched PubMed and Ovid Medline databases for the terms “vape”, “vaping”, “e-cigarette”, “electronic cigarette”, “electronic nicotine delivery”, “electronic nicotine device”, “END”, “EVALI”, “lung injury, diagnosis, management, and treatment” to find articles published between January 2000 and December 2021. We also identified references from the Centers for Disease Control and Prevention (CDC) website, as well as relevant review articles and public policy resources. Prioritization was given to peer reviewed articles written in English in moderate-to-high impact journals, consensus statements, guidelines, and included randomized controlled trials, systematic reviews, meta-analyses, and case series. We excluded publications that had a qualitative research design, or for which a conflict of interest in funding could be identified, as defined by any funding source or consulting fee from nicotine manufacturers or distributors. Search terms were chosen to generate a broad selection of literature that reflected historic and current understanding of the effects of vaping on respiratory health.

The origins of vaping

Vaping achieved widespread popularity over the past decade, but its origins date back almost a century and are summarized in figure 1 . The first known patent for an “electric vaporizer” was granted in 1930, intended for aerosolizing medicinal compounds. 23 Subsequent patents and prototypes never made it to market, 24 and it wasn’t until 1979 that the first vape pen was commercialized. Dubbed the “Favor” cigarette, the device was heralded as a smokeless alternative to cigarettes and led to the term “vaping” being coined to differentiate the “new age” method of nicotine consumption from conventional, combustible cigarettes. 25 “Favor” cigarettes did not achieve widespread appeal, in part because of the bitter taste of the aerosolized freebase nicotine; however, the term vaping persisted and would go on to be used by the myriad products that have since been developed.

Timeline of vape pen invention to widespread use (1970s-2020)

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The forerunner of the modern vape pen was developed in Beijing in 2003 and later introduced to US markets around 2006. 26 27 Around this time, the future Juul Laboratories founders developed the precursor of the current Juul vape pen while they were students at the Stanford Byers-Center for Biodesign. 28 Their model included disposable cartridges of flavored nicotine solution (pods) that could be inserted into the vape pen, which itself resembled a USB flash drive. Key to their work was the chemical alteration of freebase nicotine to a benzoate nicotine salt. 29 The lower pH of the nicotine salt resulted in an aerosolized nicotine product that lacked a bitter taste, 30 and enabled manufacturers to expand the range of flavored vape products. 31 Juul Laboratories was founded a decade later and quickly rose to dominate the US market, 32 accounting for an estimated 13-59% of the vape products used among teens by 2020. 6 8 Part of the Juul vape pen’s appeal stems from its discreet design, as well as its ability to deliver nicotine with an efficiency matching that of conventional cigarettes. 33 34 Subsequent generations of vape pens have included innovations such as the tank system, which allowed users to select from the wide range of different vape solutions on the market, rather than the relatively limited selection available in traditional pod based systems. Further customizations include the ability to select different vape pen components such as atomizers, heating coils, and fluid wicks, allowing users to calibrate the way in which the vape aerosol is produced. Tobacco companies have taken note of the shifting demographics of nicotine users, as evidenced in 2018 by Altria’s $12.8bn investment in Juul Laboratories. 35

Vaping terminology

At present, vaping serves as an umbrella term that describes multiple modalities of aerosolized nicotine consumption. Vape pens are alternatively called e-cigarettes, electronic nicotine delivery systems (END), e-cigars, and e-hookahs. Additional vernacular terms have emerged to describe both the various vape pen devices (eg, tank, mod, dab pen), vape solution (eg, e-liquid, vape juice), as well as the act of vaping (eg, ripping, juuling, puffing, hitting). 36 A conventional vape pen is a battery operated handheld device that contains a storage chamber for the vape solution and an internal element for generating the characteristic vape aerosol. Multiple generations of vape pens have entered the market, including single use, disposable varieties, as well as reusable models that have either a refillable fluid reservoir or a disposable cartridge for the vape solution. Aerosol generation entails a heating coil that atomizes the vape solution, and it is increasingly popular for devices to include advanced settings that allow users to adjust features of the aerosolized nicotine delivery. 37 38 Various devices allow for coil temperatures ranging from 110 °C to over 1000 °C, creating a wide range of conditions for thermal degradation of the vape solution itself. 39 40

The sheer number of vape solutions on the market poses a challenge in understanding the impact of vaping on respiratory health. The spectrum of vape solutions available encompasses thousands of varieties of flavors, additives, and nicotine concentrations. 41 Most vape solutions contain an active ingredient, commonly nicotine 42 ; however, alternative agents include tetrahydrocannabinol (THC) or cannabidiol (CBD). Vape solutions are typically composed of a combination of a flavorant, nicotine, and a carrier, commonly propylene glycol or vegetable glycerin, that generates the characteristic smoke appearance of vape aerosols. Some 450 brands of vape now offer more than 8000 flavors, 41 a figure that nearly doubled over a three year period. 43 Such tremendous variety does not account for third party sellers who offer users the option to customize a vape solution blend. Addition of marijuana based products such as THC or CBD requires the use of an oil based vape solution carrier to allow for extraction of the psychoactive elements. Despite THC vaping use in nearly 9% of high schoolers, 44 THC vape solutions are subject to minimal market regulation. Finally, a related modality of THC consumption is termed dabbing, and describes the process of inhaling aerosolized THC wax concentrate.

Epidemiology of vaping

Since the early 2000s, vaping has grown in popularity in the US and elsewhere. 8 45 Most of the 68 million vape pen users are concentrated in China, the US, and Europe. 46 Uptake among young people has been particularly pronounced, and in the US vaping has overtaken cigarettes as the most common modality of nicotine consumption among adolescents and young adults. 47 Studies estimate that 20% of US high school students are regular vape pen users, 6 48 in contrast to the 5% of adults who use vape products. 2 Teen uptake of vaping has been driven in part by a perception of vaping as a safer alternative to cigarettes, 49 50 as well as marketing strategies that target adolescents. 33 Teen use of vape pens is further driven by the low financial cost of initiation, with “starter kits” costing less than $25, 51 as well as easy access through peer sales and inconsistent age verification at in-person and online retailers. 52 After sustained growth in use over the 2010s, recent survey data from 2020 suggest that the number of vape pen users has leveled off among teens, perhaps in part owing to increased perceived risk of vaping after the EVALI outbreak. 8 53 The public health implications of teen vaping are compounded by the prevalence of vaping among never smokers (defined as having smoked fewer than 100 lifetime cigarettes), 54 and subsequent uptake of cigarette smoking among vaping teens. 4 55 Similarly, half of adults who currently vape have never used cigarettes, 2 and concern remains that vaping serves as a gateway to conventional cigarette use, 56 57 although these results have been disputed. 58 59 Despite regulation limiting the sale of flavored vape products, 60 a 2020 survey found that high school students were still predominantly using fruit, mint, menthol, and dessert flavored vape solutions. 48 While most data available surround the use of nicotine-containing vape products, a recent meta-analysis showed growing prevalence of adolescents using cannabis-containing products as well. 61

Vaping as harm reduction

Despite facing ongoing questions about safety, vaping has emerged as a potential tool for harm reduction among cigarette smokers. 12 27 An NHS report determined that vaping nicotine is “around 95% less harmful than cigarettes,” 62 leading to the development of programs that promote vaping as a tool of risk reduction among current smokers. A 2020 Cochrane review found that vaping nicotine assisted with smoking cessation over placebo 63 and recent work found increased rates of cigarette abstinence (18% v 9.9%) among those switching to vaping compared with conventional nicotine replacement (eg, gum, patch, lozenge). 64 US CDC guidance suggests that vaping nicotine may benefit current adult smokers who are able to achieve complete cigarette cessation by switching to vaping. 65 66

The public health benefit of vaping for smoking cessation is counterbalanced by vaping uptake among never smokers, 2 54 and questions surrounding the safety of chronic vaping. 10 11 Controversy surrounding the NHS claim of vaping as 95% safer than cigarettes has emerged, 67 68 and multiple leading health organizations have concluded that vaping is harmful. 42 69 Studies have demonstrated airborne particulate matter in the proximity of active vapers, 70 and concern remains that secondhand exposure to vaped aerosols may cause adverse effects, complicating the notion of vaping as a net gain for public health. 71 72 Uncertainty about the potential chronic consequences of vaping combined with vaping uptake among never smokers has complicated attempts to generate clear policy guidance. 73 74 Further, many smokers may exhibit “dual use” of conventional cigarettes and vape pens simultaneously, further complicating efforts to understand the impact of vape exposure on respiratory health, and the role vape use may play in smoking cessation. 12 We are unable to know with certainty the extent of nicotine uptake among young people that would have been seen in the absence of vaping availability, and it remains possible that some young vape pen users may have started on conventional cigarettes regardless. That said, declining nicotine use over the past several decades would argue that many young vape pen users would have never had nicotine uptake had vape pens not been introduced. 1 2 It remains an open question whether public health measures encouraging vaping for nicotine cessation will benefit current smokers enough to offset the impact of vaping uptake among young, never smokers. 75

Vaping lung injury—clinical presentations

Vaping related lung injury: 2012-19.

The potential health effects of vape pen use are varied and centered on injury to the airways and lung parenchyma. Before the 2019 EVALI outbreak, the medical literature detailed case reports of sporadic vaping related acute lung injury. The first known case was reported in 2012, when a patient presented with cough, diffuse ground glass opacities, and lipid laden macrophages (LLM) on bronchoalveolar lavage (BAL) return in the context of vape pen use. 76 Over the following seven years, an additional 15 cases of vaping related acute lung injury were reported in the literature. These cases included a wide range of diffuse parenchymal lung disease without any clear unifying features, and included cases of eosinophilic pneumonia, 77 78 79 hypersensitivity pneumonitis, 80 organizing pneumonia, 81 82 diffuse alveolar hemorrhage, 83 84 and giant cell foreign body reaction. 85 Although parenchymal lung injury predominated the cases reported, additional cases detailed episodes of status asthmaticus 86 and pneumothoraces 87 attributed to vaping. Non-respiratory vape pen injury has also been described, including cases of nicotine toxicity from vape solution ingestion, 88 89 and injuries sustained owing to vape pen device explosions. 90

The 2019 EVALI outbreak

In the summer of 2019 the EVALI outbreak led to 2807 cases of idiopathic acute lung injury in predominantly young, healthy individuals, which resulted in 68 deaths. 19 91 Epidemiological work to uncover the cause of the outbreak identified an association with vaping, particularly the use of THC-containing products, among affected individuals. CDC criteria for EVALI ( box 1 ) included individuals presenting with respiratory symptoms who had pulmonary infiltrates on imaging in the context of having vaped or dabbed within 90 days of symptom onset, without an alternative identifiable cause. 92 93 After peaking in September 2019, EVALI case numbers steadily declined, 91 likely owing to identification of a link with vaping, and subsequent removal of offending agents from circulation. Regardless, sporadic cases continue to be reported, and a high index of suspicion is required to differentiate EVALI from covid-19 pneumonia. 94 95 A strong association emerged between EVALI cases and the presence of vitamin E acetate in the BAL return of affected individuals 96 ; however, no definitive causal link has been established. Interestingly, the EVALI outbreak was nearly entirely contained within the US with the exception of several dozen cases, at least one of which was caused by an imported US product. 97 98 99 The pattern of cases and lung injury is most suggestive of a vape solution contaminant that was introduced into the distribution pipeline in US markets, leading to a geographically contained pattern of lung injury among users. CDC case criteria for EVALI may have obscured a potential link between viral pneumonia and EVALI, and cases may have been under-recognized following the onset of the covid-19 pandemic.

CDC criteria for establishing EVALI diagnosis

Cdc lung injury surveillance, primary case definitions, confirmed case.

Vape use* in 90 days prior to symptom onset; and

Pulmonary infiltrate on chest radiograph or ground glass opacities on chest computed tomography (CT) scan; and

Absence of pulmonary infection on initial investigation†; and

Absence of alternative plausible diagnosis (eg, cardiac, rheumatological, or neoplastic process).

Probable case

Pulmonary infiltrate on chest radiograph or ground glass opacities on chest CT; and

Infection has been identified; however is not thought to represent the sole cause of lung injury OR minimum criteria** to exclude infection have not been performed but infection is not thought to be the sole cause of lung injury

*Use of e-cigarette, vape pen, or dabbing.

†Minimum criteria for absence of pulmonary infection: negative respiratory viral panel, negative influenza testing (if supported by local epidemiological data), and all other clinically indicated infectious respiratory disease testing is negative.

EVALI—clinical, radiographic, and pathologic features

In the right clinical context, diagnosis of EVALI includes identification of characteristic radiographic and pathologic features. EVALI patients largely fit a pattern of diffuse, acute lung injury in the context of vape pen exposure. A systematic review of 200 reported cases of EVALI showed that those affected were predominantly men in their teens to early 30s, and most (80%) had been using THC-containing products. 100 Presentations included predominantly respiratory (95%), constitutional (87%), and gastrointestinal symptoms (73%). Radiological studies mostly featured diffuse ground glass opacities bilaterally. Of 92 cases that underwent BAL, alveolar fluid samples were most commonly neutrophil predominant, and 81% were additionally positive for LLM on Oil Red O staining. Lung biopsy was not required to achieve the diagnosis; however, of 33 cases that underwent tissue biopsy, common features included organizing pneumonia, inflammation, foamy macrophages, and fibrinous exudates.

EVALI—outcomes

Most patients with EVALI recovered, and prognosis was generally favorable. A systematic review of identified cases found that most patients with confirmed disease required admission to hospital (94%), and a quarter were intubated. 100 Mortality among EVALI patients was low, with estimates around 2-3% across multiple studies. 101 102 103 Mortality was associated with age over 35 and underlying asthma, cardiac disease, or mental health conditions. 103 Notably, the cohorts studied only included patients who presented for medical care, and the samples are likely biased toward a more symptomatic population. It is likely that many individuals experiencing mild symptoms of EVALI did not present for medical care, and would have self-discontinued vaping following extensive media coverage of the outbreak at that time. Although most EVALI survivors recovered well, case series of some individuals show persistent radiographic abnormalities 101 and sustained reductions in DLCO. 104 105 Pulmonary function evaluation of EVALI survivors showed normalization in FEV 1 /FVC on spirometry in some, 106 while others had more variable outcomes. 105 107 108

Vaping induced lung injury—pathophysiology

The causes underlying vaping related acute lung injury remain interesting to clinicians, scientists, and public health officials; multiple mechanisms of injury have been proposed and are summarized in figure 2 . 31 109 110 Despite increased scientific interest in vaping related lung injury following the EVALI outbreak, the pool of data from which to draw meaningful conclusions is limited because of small scale human studies and ongoing conflicts due to tobacco industry funding. 111 Further, insufficient time has elapsed since widespread vaping uptake, and available studies reflect the effects of vaping on lung health over a maximum 10-15 year timespan. The longitudinal effects of vaping may take decades to fully manifest and ongoing prospective work is required to better understand the impacts of vaping on respiratory health.

Schematic illustrating pathophysiology of vaping lung injury

Pro-inflammatory vape aerosol effects

While multiple pathophysiological pathways have been proposed for vaping related lung injury, they all center on the vape aerosol itself as the conduit of lung inflammation. Vape aerosols have been found to harbor a number of toxic substances, including thermal degradation products of the various vape solution components. 112 Mass spectrometry analysis of vape aerosols has identified a variety of oxidative and pro-inflammatory substances including benzene, acrolein, volatile organic compounds, and propylene oxide. 16 17 Vaping additionally leads to airway deposition of ultrafine particles, 14 113 as well as the heavy metals manganese and zinc which are emitted from the vaping coils. 15 114 Fourth generation vape pens allow for high wattage aerosol generation, which can cause airway epithelial injury and tissue hypoxia, 115 116 as well as formaldehyde exposure similar to that of cigarette smoke. 117 Common carrier solutions such as propylene glycol have been associated with increased airway hyper-reactivity among vape pen users, 31 118 119 and have been associated with chronic respiratory conditions among theater workers exposed to aerosolized propylene glycol used in the generation of artificial fog. 120 Nicotine salts used in pod based vape pen solutions, including Juul, have been found to penetrate the cell membrane and have cytotoxic effects. 121

The myriad available vape pen flavors correlate with an expansive list of chemical compounds with potential adverse respiratory effects. Flavorants have come under increased scrutiny in recent years and have been found to contribute to the majority of aldehyde production during vape aerosol production. 122 Compounds such as cinnamaldehyde, 123 124 2,5-dimethylpyrazine (chocolate flavoring), 125 and 2,3-pentanedione 126 are common flavor additives and have been found to contribute to airway inflammation and altered immunological responses. The flavorant diacetyl garnered particular attention after it was identified on mass spectrometry in most vape solutions tested. 127 Diacetyl is most widely associated with an outbreak of diacetyl associated bronchiolitis obliterans (“popcorn lung”) among workers at a microwave popcorn plant in 2002. 128 Identification of diacetyl in vape solutions raises the possibility of development of a similar pattern of bronchiolitis obliterans among individuals who have chronic vape aerosol exposure to diacetyl-containing vape solutions. 129

Studies of vape aerosols have suggested multiple pro-inflammatory effects on the respiratory system. This includes increased airway resistance, 130 impaired response to infection, 131 and impaired mucociliary clearance. 132 Vape aerosols have further been found to induce oxidative stress in lung epithelial cells, 133 and to both induce DNA damage and impair DNA repair, consistent with a potential carcinogenic effect. 134 Mice chronically exposed to vape aerosols developed increased airway hyper-reactivity and parenchymal changes consistent with chronic obstructive pulmonary disease. 135 Human studies have been more limited, but reveal increased airway edema and friability among vape pen users, as well as altered gene transcription and decreased innate immunity. 136 137 138 Upregulation of neutrophil elastase and matrix metalloproteases among vape users suggests increased proteolysis, potentially putting those patients at risk of chronic respiratory conditions. 139

THC-containing products

Of particular interest during the 2019 EVALI outbreak was the high prevalence of THC use among EVALI cases, 19 raising questions about a novel mechanism of lung injury specific to THC-containing vape solutions. These solutions differ from conventional nicotine based products because of the need for a carrier capable of emulsifying the lipid based THC component. In this context, additional vape solution ingredients rose to attention as potential culprits—namely, THC itself, which has been found to degrade to methacrolein and benzene, 140 as well as vitamin E acetate which was found to be a common oil based diluent. 141

Vitamin E acetate has garnered increasing attention as a potential culprit in the pathophysiology of the EVALI outbreak. Vitamin E acetate was found in 94% of BAL samples collected from EVALI patients, compared with none identified in unaffected vape pen users. 96 Thermal degradation of vitamin E acetate under conditions similar to those in THC vape pens has shown production of ketene, alkene, and benzene, which may mediate epithelial lung injury when inhaled. 39 Previous work had found that vitamin E acetate impairs pulmonary surfactant function, 142 and subsequent studies have shown a dose dependent adverse effect on lung parenchyma by vitamin E acetate, including toxicity to type II pneumocytes, and increased inflammatory cytokines. 143 Mice exposed to aerosols containing vitamin E acetate developed LLM and increased alveolar protein content, suggesting epithelial injury. 140 143

The pathophysiological insult underlying vaping related lung injury may be multitudinous, including potentially compound effects from multiple ingredients comprising a vape aerosol. The heterogeneity of available vape solutions on the market further complicates efforts to pinpoint particular elements of the vape aerosol that may be pathogenic, as no two users are likely to be exposed to the same combination of vape solution products. Further, vape users may be exposed to vape solutions containing terpenes, medium chain triglycerides, or coconut oil, the effects of which on respiratory epithelium remain under investigation. 144

Lipid laden macrophages

Lipid laden alveolar macrophages have risen to prominence as potential markers of vaping related lung injury. Alveolar macrophages describe a scavenger white blood cell responsible for clearing alveolar spaces of particulate matter and modulating the inflammatory response in the lung parenchyma. 145 LLM describe alveolar macrophages that have phagocytosed fat containing deposits, as seen on Oil Red O staining, and have been described in a wide variety of pulmonary conditions, including aspiration, lipoid pneumonia, organizing pneumonia, and medication induced pneumonitis. 146 147 During the EVALI outbreak, LLM were identified in the alveolar spaces of affected patients, both in the BAL fluid and on both transbronchial and surgical lung biopsies. 148 149 Of 52 EVALI cases reported in the literature who underwent BAL, LLM were identified in over 80%. 19 100 101 148 149 150 151 152 153 Accordingly, attention turned to LLM as not only a potential marker of lung injury in EVALI, but as a possible contributor to lung inflammation itself. This concern was compounded by the frequent reported use of oil based THC vape products among EVALI patients, raising the possibility of lipid deposits in the alveolus resulting from inhalation of THC-containing vape aerosols. 154 The combination of LLM, acute lung injury, and inhalational exposure to an oil based substance raised the concern for exogenous lipoid pneumonia. 152 153 However, further evaluation of the radiographic and histopathologic findings failed to identify cardinal features that would support a diagnosis of exogenous lipoid pneumonia—namely, low attenuation areas on CT imaging and foreign body giant cells on histopathology. 155 156 However, differences in the particle size and distribution between vape aerosol exposure and traditional causes of lipoid pneumonia (ie, aspiration of a large volume of an oil-containing substance), could reasonably lead to differences in radiographic appearance, although this would not account for the lack of characteristic histopathologic features on biopsy that would support a diagnosis of lipoid pneumonia.

Recent work suggests that LLM reflect a non-specific marker of vaping, rather than a marker of lung injury. One study found that LLM were not unique to EVALI and could be identified in healthy vape pen users, as well as conventional cigarette smokers, but not in never smokers. 157 Interestingly, this work showed increased cytokines IL-4 and IL-10 among healthy vape users, suggesting that cigarette and vape pen use are associated with a pro-inflammatory state in the lung. 157 An alternative theory supports LLM presence reflecting macrophage clearance of intra-alveolar cell debris rather than exogenous lipid exposure. 149 150 Such a pattern would be in keeping with the role of alveolar macrophages as modulating the inflammatory response in the lung parenchyma. 158 Taken together, available data would support LLM serving as a non-specific marker of vape product use, rather than playing a direct role in vaping related lung injury pathogenesis. 102

Clinical aspects

A high index of suspicion is required in establishing a diagnosis of vaping related lung injury, and a general approach is summarized in figure 3 . Clinicians may consider the diagnosis when faced with a patient with new respiratory symptoms in the context of vape pen use, without an alternative cause to account for their symptoms. Suspicion should be especially high if respiratory complaints are coupled with constitutional and gastrointestinal symptoms. Patients may present with non-specific markers indicative of an ongoing inflammatory process: fevers, leukocytosis, elevated C reactive protein, or elevated erythrocyte sedimentation rate. 19

Flowchart outlining the procedure for diagnosing a vaping related lung injury

Vaping related lung injury is a diagnosis of exclusion. Chest imaging via radiograph or CT may identify a variety of patterns, although diffuse ground glass opacities remain the most common radiographic finding. Generally, patients with an abnormal chest radiograph should undergo a chest CT for further evaluation of possible vaping related lung injury.

Exclusion of infectious causes is recommended. Testing should include evaluation for bacterial and viral causes of pneumonia, as deemed appropriate by clinical judgment and epidemiological data. Exclusion of common viral causes of pneumonia is imperative, particularly influenza and SARS-CoV-2. Bronchoscopy with BAL should be considered on a case-by-case basis for those with more severe disease and may be helpful to identify patients with vaping mediated eosinophilic lung injury. Further, lung biopsy may be beneficial to exclude alternative causes of lung injury in severe cases. 92

No definitive therapy has been identified for the treatment of vaping related lung injury, and data are limited to case reports and public health guidance on the topic. Management includes supportive care and strong consideration for systemic corticosteroids for severe cases of vaping related lung injury. CDC guidance encourages consideration of systemic corticosteroids for patients requiring admission to hospital, or those with higher risk factors for adverse outcomes, including age over 50, immunosuppressed status, or underlying cardiopulmonary disease. 100 Further, given case reports of vaping mediated acute eosinophilic pneumonia, steroids should be implemented in those patients who have undergone a confirmatory BAL. 77 79

Additional therapeutic options include empiric antibiotics and/or antivirals, depending on the clinical scenario. For patients requiring admission to hospital, prompt subspecialty consultation with a pulmonologist can help guide management. Outpatient follow-up with chest imaging and spirometry is recommended, as well as referral to a pulmonologist. Counseling regarding vaping cessation is also a core component in the post-discharge care for this patient population. Interventions specific to vaping cessation remain under investigation; however, literature supports the use of behavioral counseling and/or pharmacotherapy to support nicotine cessation efforts. 66

Health outcomes among vape pen users

Health outcomes among chronic vape pen users remains an open question. To date, no large scale prospective cohort studies exist that can establish a causal link between vape use and adverse respiratory outcomes. One small scale prospective cohort study did not identify any spirometric or radiographic changes among vape pen users over a 3.5 year period. 159 Given that vaping remains a relatively novel phenomenon, many users will have a less than 10 “pack year” history of vape pen use, arguably too brief an exposure period to reflect the potential harmful nature of chronic vaping. Studies encompassing a longer period of observation of vape pen users have not yet taken place, although advances in electronic medical record (EMR) data collection on vaping habits make such work within reach.

Current understanding of the health effects of vaping is largely limited to case reports of acute lung injury, and health surveys drawing associations between vaping exposure and patient reported outcomes. Within these limitations, however, early work suggests a correlation between vape pen use and poorer cardiopulmonary outcomes. Survey studies of teens who regularly vape found increased frequencies of respiratory symptoms, including productive cough, that were independent of smoking status. 160 161 These findings were corroborated in a survey series identifying more severe asthma symptoms and more days of school missed owing to asthma among vape pen users, regardless of cigarette smoking status. 162 163 164 Studies among adults have shown a similar pattern, with increased prevalence of chronic respiratory conditions (ie, asthma or chronic obstructive pulmonary disease) among vape pen users, 165 166 and higher risk of myocardial infarction and stroke, but lower risk of diabetes. 167

The effects of vaping on lung function as determined by spirometric studies are more varied. Reported studies have assessed lung function after a brief exposure to vape aerosols, varying from 5-60 minutes in duration, and no longer term observational cohort studies exist. While some studies have shown increased airway resistance after vaping exposure, 130 168 169 others have shown no change in lung function. 137 170 171 The cumulative exposure of habitual vape pen users to vape aerosols is much longer than the period evaluated in these studies, and the impact of vaping on longer term respiratory heath remains to be seen. Recent work evaluating ventilation-perfusion matching among chronic vapers compared with healthy controls found increased ventilation-perfusion mismatch, despite normal spirometry in both groups. 172 Such work reinforces the notion that changes in spirometry are a feature of more advanced airways disease, and early studies, although inconsistent, may foreshadow future respiratory impairment in chronic vapers.

Covid-19 and vaping

The covid-19 pandemic brought renewed attention to the potential health impacts of vaping. Studies investigating the role of vaping in covid-19 prevalence and outcomes have been limited by the small size of the populations studied and results have been inconsistent. Early work noted a geographic association in the US between vaping prevalence and covid-19 cases, 173 and a subsequent survey study found that a covid-19 diagnosis was five times more likely among teens who had ever vaped. 174 In contrast, a UK survey study found no association between vaping status and covid-19 infection rates, although captured a much smaller population of vape pen users. 175 Reports of nicotine use upregulating the angiotensin converting enzyme 2 (ACE-2) receptor, 176 which serves as the binding site for SARS-CoV-2 entry, raised the possibility of increased susceptibility to covid-19 among chronic nicotine vape pen users. 177 178 Further, vape use associated with sharing devices and frequent touching of the mouth and face were posited as potential confounders contributing to increased prevalence of covid-19 in this population. 179

Covid-19 outcomes among chronic vape pen users remain an open question. While smoking has been associated with progression to more severe infections, 180 181 no investigation has been performed to date among vaping cohorts. The young average age of chronic vape pen users may prove a protective factor, as risk of severe covid-19 infection has been shown to increase with age. 182 Regardless, a prudent recommendation remains to abstain from vaping to mitigate risk of progression to severe covid-19 infection. 183

Increased awareness of respiratory health brought about by covid-19 and EVALI is galvanizing the changing patterns in vape pen use. 184 Survey studies have consistently shown trends toward decreasing use among adolescents and young adults. 174 185 186 In one study, up to two thirds of participants endorsed decreasing or quitting vaping owing to a combination of factors including difficulty purchasing vape products during the pandemic, concerns about vaping effects on lung health, and difficulty concealing vape use while living with family. 174 Such results are reflected in nationwide trends that show halting growth in vaping use among high school students. 8 These trends are encouraging in that public health interventions countering nicotine use among teens may be meeting some measure of success.

Clinical impact—collecting and recording a vaping history

Vaping history in electronic medical records.

Efforts to prevent, diagnose, and treat vaping related lung injury begin with the ability of our healthcare system to identify vape users. Since vaping related lung injury remains a diagnosis of exclusion, clinicians must have a high index of suspicion when confronted with idiopathic lung injury in a patient with vaping exposure. Unlike cigarette use, vape pen use is not built into most EMR systems, and is not included in meaningful use criteria for EMRs. 187 Retrospective analysis of outpatient visits showed that a vaping history was collected in less than 0.1% of patients in 2015, 188 although this number has been increasing. 189 190 In part augmented by EMR frameworks that prompt collection of data on vaping history, more recent estimates indicate that a vaping history is being collected in up to 6% of patients. 191 Compared with the widespread use of vaping, particularly among adolescent and young adult populations, this number remains low. Considering generational trends in nicotine use, vaping will likely eventually overcome cigarettes as the most common mode of nicotine use, raising the importance of collecting a vaping related history. Further, EMR integration of vaping history is imperative to allow for retrospective, large scale analyses of vape exposure on longitudinal health outcomes at a population level.

Practical considerations—gathering a vaping history

As vaping becomes more common, the clinician’s ability to accurately collect a vaping history and identify patients who may benefit from nicotine cessation programs becomes more important. Reassuringly, gathering a vaping history is not dissimilar to asking about smoking and use of other tobacco products, and is summarized in box 2 . Collecting a vaping history is of particular importance for providers caring for adolescents and young adults who are among the highest risk demographics for vape pen use. Adolescents and young adults may be reluctant to share their vaping history, particularly if they are using THC-containing or CBD-containing vape solutions. Familiarity with vernacular terms to describe vaping, assuming a non-judgmental approach, and asking parents or guardians to step away during history taking will help to break down these barriers. 192

Practical guide to collecting a vaping history

Ask with empathy.

Young adults may be reluctant to share history of vaping use. Familiarity with vaping terminology, asking in a non-judgmental manner, and asking in a confidential space may help.

Ask what they are vaping

Vape products— vape pens commonly contain nicotine or an alternative active ingredient, such as THC or CBD. Providers may also inquire about flavorants, or other vape solution additives, that their patient is consuming, particularly if vaping related lung injury is suspected.

Source— ask where they source their product from. Sources may include commercially available products, third party distributors, or friends or local contacts.

Ask how they are vaping

Device— What style of device are they using?

Frequency— How many times a day do they use their vape pen (with frequent use considered >5 times a day)? Alternatively, providers may inquire how long it takes to deplete a vape solution cartridge (with use of one or more pods a day considered heavy use).

Nicotine concentration— For individuals consuming nicotine-containing products, clinicians may inquire about concentration and frequency of use, as this may allow for development of a nicotine replacement therapy plan.

Ask about other inhaled products

Clinicians should ask patients who vape about use of other inhaled products, particularly cigarettes. Further, clinicians may ask about use of water pipes, heat-not-burn devices, THC-containing products, or dabbing.

The following provides a practical guide on considerations when collecting a vaping history. Of note, collecting a partial history is preferable to no history at all, and simply recording whether a patient is vaping or not adds valuable information to the medical record.

Vape use— age at time of vaping onset and frequency of vape pen use. Vape pen use >5 times a day would be considered frequent. Alternatively, clinicians may inquire how long it takes to deplete a vape solution pod (use of one or more pods a day would be considered heavy use), or how frequently users are refilling their vape pens for refillable models.

Vape products— given significant variation in vape solutions available on the market, and variable risk profiles of the multitude of additives, inquiring as to which products a patient is using may add useful information. Further, clinicians may inquire about use of nicotine versus THC-containing vape solutions, and whether said products are commercially available or are customized by third party sellers.

Concurrent smoking— simultaneous use of multiple inhaled products is common among vape users, including concurrent use of conventional cigarettes, water pipes, heat-not-burn devices, and THC-containing or CBD-containing products. Among those using marijuana products, gathering a history regarding the type of product use, the device, and the modality of aerosol generation may be warranted. Gathering such detailed information may be challenging in the face of rapidly evolving product availability and changing popular terminology. Lastly, clinicians may wish to inquire about “dabbing”—the practice of inhaling heated butane hash oil, a concentrated THC wax—which may also be associated with lung injury. 193

Future directions

Our understanding of the effects of vaping on respiratory health is in its early stages and multiple trials are under way. Future work requires enhanced understanding of the effects of vape aerosols on lung biology, such as ongoing investigations into biomarkers of oxidative stress and inflammation among vape users (clinicaltrials.gov NCT03823885 ). Additional studies seek to elucidate the relation between vape aerosol exposure and cardiopulmonary outcomes among vape pen users ( NCT03863509 , NCT05199480 ), while an ongoing prospective cohort study will allow for longitudinal assessment of airway reactivity and spirometric changes among chronic vape pen users ( NCT04395274 ).

Public health and policy interventions are vital in supporting both our understanding of vaping on respiratory health and curbing the vaping epidemic among teens. Ongoing, large scale randomized controlled studies seek to assess the impact of the FDA’s “The Real Cost” advertisement campaign for vaping prevention ( NCT04836455 ) and another trial is assessing the impact of a vaping prevention curriculum among adolescents ( NCT04843501 ). Current trials are seeking to understand the potential for various therapies as tools for vaping cessation, including nicotine patches ( NCT04974580 ), varenicline ( NCT04602494 ), and text message intervention ( NCT04919590 ).

Finally, evaluation of vaping as a potential tool for harm reduction among current cigarette smokers is undergoing further evaluation ( NCT03235505 ), which will add to the body of work and eventually lead to clear policy guidance.

Several guidelines on the management of vaping related lung injury have been published and are summarized in table 1 . 194 195 196 Given the relatively small number of cases, the fact that vaping related lung injury remains a newer clinical entity, and the lack of clinical trials on the topic, guideline recommendations reflect best practices and expert opinion. Further, published guidelines focus on the diagnosis and management of EVALI, and no guidelines exist to date for the management of vaping related lung injury more generally.

Summary of clinical guidelines

• View inline

Conclusions

Vaping has grown in popularity internationally over the past decade, in part propelled by innovations in vape pen design and nicotine flavoring. Teens and young adults have seen the biggest uptake in use of vape pens, which have superseded conventional cigarettes as the preferred modality of nicotine consumption. Despite their widespread popularity, relatively little is known about the potential effects of chronic vaping on the respiratory system, and a growing body of literature supports the notion that vaping is not without risk. The 2019 EVALI outbreak highlighted the potential harms of vaping, and the consequences of long term use remain unknown.

Discussions regarding the potential harms of vaping are reminiscent of scientific debates about the health effects of cigarette use in the 1940s. Interesting parallels persist, including the fact that only a minority of conventional cigarette users develop acute lung injury, yet the health impact of sustained, longitudinal cigarette use is unquestioned. The true impact of vaping on respiratory health will manifest over the coming decades, but in the interval a prudent and time tested recommendation remains to abstain from consumption of inhaled nicotine and other products.

Questions for future research

How does chronic vape aerosol exposure affect respiratory health?

Does use of vape pens affect respiratory physiology (airway resistance, V/Q matching, etc) in those with underlying lung disease?

What is the role for vape pen use in promoting smoking cessation?

What is the significance of pulmonary alveolar macrophages in the pathophysiology of vaping related lung injury?

Are particular populations more susceptible to vaping related lung injury (ie, by sex, demographic, underlying comorbidity, or age)?

Series explanation: State of the Art Reviews are commissioned on the basis of their relevance to academics and specialists in the US and internationally. For this reason they are written predominantly by US authors

Contributors: AJ conceived of, researched, and wrote the piece. She is the guarantor.

Competing interests: I have read and understood the BMJ policy on declaration of interests and declare the following interests: AJ receives consulting fees from DawnLight, Inc for work unrelated to this piece.

Patient involvement: No patients were directly involved in the creation of this article.

Provenance and peer review: Commissioned; externally peer reviewed.

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Perceptions and Experiences of Vaping Among Youth and Young Adult E-Cigarette Users: Considering Age, Gender, and Tobacco Use

Affiliations.

• 1 Department of Psychology, Saint Mary's University, Nova Scotia, Canada; The Lung Association of Nova Scotia, Nova Scotia, Canada. Electronic address: [email protected].
• 2 Department of Community Health and Epidemiology, Dalhousie University, Nova Scotia, Canada; The Lung Association of Nova Scotia, Nova Scotia, Canada.
• 3 The Lung Association of Nova Scotia, Nova Scotia, Canada.
• 4 Department of Criminology, Saint Mary's University, Nova Scotia, Canada; The Lung Association of Nova Scotia, Nova Scotia, Canada.
• PMID: 32943292
• DOI: 10.1016/j.jadohealth.2020.08.004

Purpose: This study examined differences in the topics of vaping perceptions (positive and negative aspects) and experiences (social media content) among e-cigarette users segmented by age and gender (male and female youth and young adults) and tobacco use (never, former, or current user).

Method: E-cigarette users (N = 558, 53.6% male, mean age: 18.6 years [SD = 2.2], mean use: 5.3 days/week [SD = 2.3]) residing in Nova Scotia, Canada, responded to three open-ended topic questions concerning vaping in an online survey. Responses to each topic (e.g., positive aspects) were coded and grouped into categories (e.g., flavors). Chi-square tests were used to examine whether groups differed by topic, and Bonferroni correction tests were used to determine specific group differences in each coded category.

Results: Age and gender groups differed in their positive perceptions of a nicotine rush, tricks, and positive social aspects of vaping and in their negative perceptions of respiratory effects, nicotine effects, product malfunction and cost, and negative social aspects of vaping. Age and gender groups also differed in exposure to tricks and branding on social media. Tobacco use groups differed in their positive perceptions of flavor, nicotine rush, tricks, low cost, enhancement, and smoking cessation and in their negative perceptions of negative social aspects and exposure to tricks on social media.

Conclusions: There are notable similarities and differences among youth and young adult e-cigarette users by age, gender, and tobacco use. Policies and interventions should incorporate these distinctions to effectively address the increasing use of e-cigarettes among young users.

Keywords: Electronic cigarette; Gender; Nicotine; Tobacco use; Young adults; Youth.

Copyright © 2020 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Publication types

• Research Support, Non-U.S. Gov't
• Electronic Nicotine Delivery Systems*
• Tobacco Products*
• Tobacco Use
• Young Adult

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Article Contents

Introduction, conclusions, supplementary material, declaration of interests.

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Systematic Review of Electronic Cigarette Use (Vaping) and Mental Health Comorbidity Among Adolescents and Young Adults

• Article contents
• Figures & tables
• Supplementary Data

Timothy D Becker, Melanie K Arnold, Vicky Ro, Lily Martin, Timothy R Rice, Systematic Review of Electronic Cigarette Use (Vaping) and Mental Health Comorbidity Among Adolescents and Young Adults, Nicotine & Tobacco Research , Volume 23, Issue 3, March 2021, Pages 415–425, https://doi.org/10.1093/ntr/ntaa171

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The prevalence of electronic cigarette (EC) use has risen dramatically among adolescents and young adults (AYA, ages 12–26) over the past decade. Despite extensive established relationships between combustible cigarette use and mental health problems, the mental health comorbidities of EC use remain unclear.

To provide a systematic review of existing literature on mental health comorbidities of EC use among AYA. Database searches using search terms related to EC, AYA, and mental health identified 1168 unique articles, 87 of which prompted full-text screening. Multiple authors extracted data, applied the Effective Public Health Practice Project Quality Assessment Tool to evaluate the evidence, and synthesized findings.

Forty articles met eligibility criteria ( n = 24 predominantly adolescent and 16 predominantly young adult). Analyses yielded three main categories of focus: internalizing disorders (including depression, anxiety, suicidality, eating disorders, post-traumatic stress disorder), externalizing disorders (attention-deficit/hyperactivity disorder and conduct disorder), and transdiagnostic concepts (impulsivity and perceived stress). Significant methodological limitations were noted.

Youth EC use is associated with greater mental health problems (compared with nonuse) across several domains, particularly among adolescents. Because many existing studies are cross-sectional, directionality remains uncertain. Well-designed longitudinal studies to investigate long-term mental health sequelae of EC use remain needed.

Forty recent studies demonstrate a variety of mental health comorbidities with AYA EC use, particularly among adolescents. Mental health comorbidities of EC use generally parallel those of combustible cigarette use, with a few exceptions. Future EC prevention and treatment strategies may be enhanced by addressing mental health.

The use of electronic cigarette (EC) has risen dramatically among adolescents and young adults (AYA, youth aged 12–26) over the past decade in countries around the world. 1 A nationwide survey of US high school students found that current use of EC increased from 1.5% in 2011 to 20.8% in 2018, despite a decrease in combustible cigarette (CC) use during this period. 2 In 2019, lifetime EC use among high school age youth exceeded 40% in the United States and Canada. 3

ECs are battery-powered devices that heat a liquid to produce an inhalable aerosol that creates sensations mimicking CC smoking. 4 The devices are alternatively referred to as vaporizers, vape-pens, vape pod systems, JUULs (a popular North American brand), and electronic nicotine delivery systems; inhalation may be described as vaping or blowing smoke. 5 The increasing popularity of ECs among youth has been attributed to aggressive marketing, 6 enticing flavors, 7 perceptions of lower harm, 8 , 9 social media influences, 10 and discreet designs that enable furtive use. 9

EC liquids can contain mixtures of solvents (eg, propylene glycol), nicotine, tetrahydrocannabinol or hash oil, hundreds of flavoring compounds, and trace heavy metals. 11–13 Some ECs (eg, JUUL) use nicotine salts, enabling consumption of very high doses of nicotine 14 , 15 that have been associated with high rates of continued use. 5 EC are a vehicle for nicotine use, but do not always contain nicotine. In a national survey of US high school students, a majority reported vaping only flavoring (59%–63%), followed by nicotine (13%–20%), and cannabis compounds (6%) 12 ; however, actual nicotine use may be higher than reported because subsequent studies have indicated that youth misperceive nicotine content of products they use. 5

Leading health organizations initially supported ECs as a possible smoking cessation aid for adults. 4 , 16 Though initially presumed less toxic than CC, EC use can cause carcinogen exposure, 17 respiratory toxicity, 18 declining oral health, 19 and other adverse effects. 11 Among AYA, EC use may act as a gateway to use of CCs 20 , 21 and to alcohol and illicit substances. 22 , 23 Some youth may be more susceptible to harmful effects than others.

AYA with mental illness are a population of specific concern. Adults with mental illness use tobacco products at high rates and die prematurely from tobacco-related illnesses, 24 a disparity attracting calls for further study. 25 Adolescence is a vulnerable developmental period for the onset of nicotine use and mental illness, 26 warranting special attention. Yet, to date, no article has yet to systematically review the evidence base concerning EC use and mental illness in youth.

CC use among adolescents is associated with externalizing (eg, attention-deficit/hyperactivity disorder [ADHD], oppositional defiant disorder, conduct disorder), internalizing (eg, depression, anxiety), and substance use disorders. 26–28 AYA with mental illness use nicotine at higher rates than peers without mental illness. 29 This may occur due to (1) attempts to self-medicate symptoms, such as cognitive deficits in ADHD or low mood, 30 (2) efforts to counteract sedating side effects of psychotropic medications, 30 (3) common underlying genetic or environmental risk factors for smoking and mental illness, 31 , 32 or (4) neurotoxic impacts of nicotine on mental health. 33 A combination of individual-specific factors likely contributes.

Nicotine adversely affects adolescent neurodevelopment 34 and increases the risk of cognitive and psychiatric disorders. 35 Although much of the available evidence derives from animal and preclinical research, we can nonetheless mobilize this knowledge while awaiting further clinical youth studies. During adolescence, brain regions that underlie executive functions undergo significant reorganization, 36 , 37 regulated in part by nicotinic acetylcholine receptors. 33 Evidence from animal models suggests that prolonged nicotine exposure may also induce epigenetic changes 33 and increase vulnerability to stress sensitivity. 38 , 39 These biological changes may, in part, underlie associations between adolescent nicotine use and subsequent development of mood disorders, 39 , 40 schizophrenia, 41 and substance use disorders. 33 Furthermore, reliance on nicotine to overcome challenges interferes with the development of adaptive coping skills. 42

Although nicotine remains the most commonly vaped substance, a substantial proportion of youth EC users vape cannabis 12 and nicotine vaping is highly comorbid with cannabis use among adolescents. 43 Vaped cannabis often comes in high-potency concentrates, leading to greater amounts consumed by vaping than other modes. 44 Like nicotine, cannabis use is associated with adverse mental health outcomes, including psychotic disorders, depression, worse symptoms of mania/hypomania in individuals with bipolar disorder, and suicidality. 45

We aim to assess the current evidence describing mental health comorbidities of EC use among AYA. Although prior reviews have assessed the mental health correlates of EC use among adults, 46 the evidence concerning relationships between EC use and AYA with mental illness remains unreviewed. As 99% of tobacco users initiate use before age 26, effective prevention and treatment efforts depend on understanding risks for use among AYA. 47

The research protocol was developed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines 48 and registered with the International Prospective Register of Systematic Reviews (PROSPERO) (Registration ID CRD42020177159).

Data Sources and Searches

A search of studies that evaluated psychiatric comorbidities associated with EC use among adolescents and young adults was conducted on March 23, 2020, within MEDLINE, EMBASE, PsycINFO, Web of Science Core Collection, and Scopus. The search strategy included appropriate controlled vocabulary and keywords for (1) mental illness, (2) AYA (ages 12–26), and (3) EC use (see Supplementary Appendix A ). Publication date was limited from January 2011 to present, and no language or article-type restrictions were included in the search strategy. Reference lists of included studies were reviewed by hand to identify any additional studies.

Study Selection

Search results were uploaded into Covidence, 49 a systematic review software package. Two authors independently assessed articles based on title and abstract using screening criteria, with a third author resolving eligibility disagreements. We chose wide eligibility criteria ( Table 1 ), since research on mental health among EC users is just emerging. Full texts of selected articles were screened to finalize decisions on eligibility ( Figure 1 ).

Inclusion and Exclusion Criteria

AYA = adolescents and young adults; EC = electronic cigarette.

a The authors agreed to add this criterion during full-text screening because the analyses presented in these papers did not contribute significantly to answering the main research question of this review.

Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) flow diagram.

Data Extraction

The authors developed and piloted a standardized data extraction tool including first author and year of publication, study aim, participants and setting, study design, response and follow-up rates, EC measurements, mental health measures, prevalence of EC use, findings related to mental health, and covariates adjusted for in analyses. The aspects pertaining to the methods were extracted by a single author and reviewed by a second author. Results were extracted independently by two authors, who discussed each article, including additional team members as needed.

Following extraction of key data, two authors independently rated the quality of each article using the Effective Public Health Practice Project Quality Assessment Tool, a valid and reliable method for assessing a diversity of research designs. 50 Studies were rated across five domains, including selection bias, study design, confounders, data collection methods, and withdrawals and dropouts ( Table 2 , Supplementary Table 1 ). Last, a global quality rating inclusive of data in all domains was assigned.

Quality Rating of Included Studies ( n = 40)

Following data extraction and discussion of included studies, findings were qualitatively synthesized by mental illness categories. Substantial methodological heterogeneity precluded quantitative meta-analysis. Key statistics are reported.

Searches identified 1706 articles, of which 1167 were unique, and 1 article was identified by hand search. Of the 1168 articles screened, 87 met eligibility by title and abstract, of which 40 were ultimately included for qualitative synthesis ( Figure 1 ).

The included articles were published from 2015 through 2020 and pertained to 29 unique cohorts ( Supplementary Table 1 ). Most articles report on data collected between 2013 and 2017. Six cohorts were described by 17 articles, whereas the remaining 23 cohorts were described by single articles. More articles studied predominantly adolescents ( n = 24 studies, representing 16 cohorts) than young adults ( n = 16 studies, representing 13 cohorts).

Most studies were conducted in the United States ( n = 23 cohorts); others included South Korea ( n = 3 cohorts), the United Kingdom ( n = 2 cohorts), and Taiwan ( n = 1 cohort). A minority of cohorts were nationally representative ( n = 7/16, 44% of adolescent cohorts, n = 2/13, 15% of YA cohorts), two were clinical samples, 51 , 52 two focused on youth at high-risk for substance use, 53 , 54 and most others were school- or university-based samples.

More than half utilized cross-sectional designs ( n = 23 articles), although a substantial number were longitudinal ( n = 16 articles, representing 11 unique cohorts), and one reported a case series. 52 All studies used self-report measures of EC use, none of which were reported to have been established as reliable and valid. EC measures varied in assessing lifetime use, current use, age of use onset, and frequency of use. Most studies ( n = 37) referred to nicotine use in EC, whereas three explicitly investigated vaporizing other substances. 51 , 55 , 56

Mental health outcomes were subgrouped by syndrome (eg, depression, anxiety, ADHD) and age under three main categories: internalizing disorders, externalizing disorders, transdiagnostic concepts. Several additional findings that did not fit the main categories are briefly presented in Table 3 . 51 , 52 , 55–59

Additional Findings

Internalizing Disorders

Internalizing symptoms (composite), adolescents:.

Composite measures of internalizing symptoms were associated with EC use among adolescents in both the Population Assessment of Tobacco and Health (PATH) study 60–64 and a study of at-risk US high school students. 54 Quality of evidence was weak to moderate, with a mix of cross-sectional and longitudinal designs.

Cross-sectional analysis of baseline PATH data revealed that high-severity lifetime internalizing problems were similarly associated with both lifetime EC (adjusted odds ratio [aOR] = 1.6, 95% confidence interval [CI]: 1.3–1.8, p < .05) and CC use (aOR = 1.7, 95% CI: 1.5–2.0, p < .05). 61 In a 1-year follow-up longitudinal analysis of baseline nicotine-naive adolescents, high past-year internalizing problems were significantly associated with initiation of EC use (adjusted relative risk ratio [aRRR] = 1.61, 95% CI: 1.12–2.33, p < .05), but not initiation of CC-only or dual EC and CC use. 60 In a cross-sectional study of students in alternative high schools (ie, schools providing nontraditional learning experiences for youth with prior educational and/or behavioral difficulties) internalizing symptoms related significantly to EC use ( B = 0.100, standard error [SE] = 0.041, OR = 1.105, p < .05) and use frequency ( B = 0.204, SE = 0.095, β = 0.0128). 54

Young Adults:

Two articles examined and found relationships between internalizing symptoms and EC use among YA respondents in the PATH study. 62 , 65 Evidence quality was similarly weak to moderate. Similar to the adolescent PATH findings, high-severity past-year internalizing problems (compared with low severity) significantly related to current EC use (aOR = 1.97, 95% CI: 1.46–2.65, p < .001) and CC use (aOR = 1.92, 95% CI: 1.64–2.24, p < .001) in cross-sectional analysis of baseline data, 65 and high-severity lifetime internalizing problems predicted onset of EC (aOR = 1.4, 95% CI: 1.1–1.8, p < .05) and CC use (aOR = 2.2, 95% CI: 1.5–3.3, p < .05) among nonusers in a 1-year longitudinal analysis. 62

Seven studies, including four distinct national cohorts (United States, Taiwan, and Korea) 66–69 and one California-based cohort 70–72 examined associations between EC use and depression among adolescents. Most found positive associations 66–69 , 71 ,72 and one suggested a bidirectional relationship. 70 Evidence quality was weak to moderate due to cross-sectional designs, single-item measures, and minimal adjustment for confounders.

In a 1-year longitudinal analysis of a California cohort, sustained EC use was associated with the escalation of depressive symptoms over time ( b = 1.272, SE = 0.513, p = .01), and past-month use frequency was positively associated with depressive symptoms ( b = 1.611, SE = 0.782, p = .04) among sustained users. 70 The remaining studies were cross-sectional. Three national studies found EC use associated with depressive symptoms, 66 , 68 , 69 although the Taiwanese study found no relationship for exclusive EC use. 67 In the Taiwan study, depression was associated with exclusive CC use (aOR = 2.2, 95% CI: 1.1–5.0) but not EC use 67 ; however, in the Korean study depression was associated with both current EC use (current use: aOR = 2.21, 95% CI: 1.67–2.93) and CC use (current use: aOR = 2.04, 95% CI: 1.86–2.24). 69

Eight studies, among six cohorts, investigated relationships between depression and EC use, with mixed results. 21 , 53 , 59 , 73–76 Most studies were weak, due to cross-sectional designs and risk of selection bias.

A Texas-based cohort provides the strongest evidence (moderate). 59 , 75 , 76 Over 2.5 years of biannual longitudinal follow-up, depressive symptoms were significantly but modestly associated with frequency of past-month use for both EC (adjusted rate ratio [aRR] = 1.01, 95% CI: 1.00–1.03, p = .02) and CC (aRR = 1.03, 95% CI: 1.02–1.04, p < .001). 75 A cross-lagged path analysis of three waves found significant paths from Wave 1 depression to Wave 2 EC use ( B = 0.06, p < .01) and Wave 2 depression to Wave 3 EC use ( B = 0.08, p < .01), but no paths from EC use to subsequent depressive symptoms. 76

Two cross-sectional studies, among college students 58 and homeless youth smokers 53 found depressive symptoms associated with current EC use (college: aOR = 1.04, 95% CI: 1.01–1.08, p = .022 58 ; homeless: aOR = 3.06, 95% CI: 1.68–5.57, p < .05 53 ). In these studies, depression was also associated with CC use in the student cohort (aOR = 1.03, 95% CI: 1.01–1.06, p = .015), but not the homeless cohort.

Finally, two longitudinal 21 , 73 and one cross-sectional study 74 found no relationships between EC use and depression. In a 2-year follow-up of Georgia college students, depressive symptoms predicted subsequent CC use (aOR = 1.05, 95% CI: 1.02–1.09, p = .001) but not EC use. 73 In study of Virginia college students, baseline depression did not predict EC initiation during 1-year of follow-up. 21

One cross-sectional study, with weak quality evidence, assessed anxiety among adolescents, using scales for several anxiety subtypes, finding EC-only use less strongly related with anxiety than CC-only use. 71 Lifetime EC-only users had higher levels of panic disorder than lifetime nicotine abstainers, but lower levels of generalized anxiety, panic, social phobia, OCD, and anxiety sensitivity than CC-only users. 71

Four studies among three cohorts have examined anxiety among YA, yielding mostly negative results. 21 , 73 , 74 , 77 Quality of evidence was weak to moderate with risks of selection bias across studies. Studies of two longitudinal cohorts of college students, in Georgia and Virginia, followed over 1–2 years found no relationship between anxiety and subsequent EC use. 21 , 73 Among the Georgia 73 but not the Virginia cohort, 21 anxiety predicted CC use (aOR = 1.02, 95% CI: 1.00–1.04, p = .02). On a smaller scale, an ecological momentary analysis among a currently smoking subset of the Georgia cohort found no relationship between anxiety and EC use. 77 A cross-sectional study found EC use associated with generalized anxiety (likelihood ratio χ   2 = 14.0, p = .001, Cramer’s V = 0.066) in a primary unadjusted analysis that resolved with secondary analysis controlling for covariates. 74

Suicidality

Four national cross-sectional studies in the United States 66 and Korea 68 , 69 , 78 investigated suicidality, consistently finding current EC use associated with suicidal ideation, plans, and attempts. Evidence quality is again weak and is limited by cross-sectional designs, possible confounding, and single-item measures.

In an analysis of the US Youth Risk Behavior Survey (2015–2017), current EC-only use associated with past-year suicidal ideation (aOR = 1.23, 95% CI: 1.03–1.47). 66 Analyses across 3 years (2015–2017) of the Korean Youth Risk Behavior Survey found similar associations. 68 , 69 , 78 The 2016 Korean survey found significant associations between current EC use (vs. nonuse) and past-year suicidal ideation (aOR = 1.58, 95% CI: 1.31–1.89, p < .05), plans (aOR = 2.44, 95% CI: 1.94–3.08, p < .05), attempts (aOR = 2.44, 95% CI: 1.85–3.22, p < .05), and serious attempts (aOR = 3.09, 95% CI: 1.51–6.32, p < .05). 78 In the 2017 Korean survey, lifetime and current CC use, EC use, and dual CC and EC use (vs. never use) were all associated with suicidal ideation, planning, and attempts, although the magnitude of associations for CC-only users seemed consistently lower than those for EC and dual users—with greater OR, but wide CIs, limiting some comparisons between groups. Furthermore, associations between suicidality and EC use were consistently stronger among women than men. 69

No studies identified.

Eating Disorders

One South Korean study examined the comorbidity between EC use and past-month report of unhealthy weight control behaviors, including one-food dieting, fasting, diet pill use, and purging, and found significant relationships among both young men and women. 79 Although the study included a large nationally representative sample, overall quality was weak, due to a cross-sectional design, possible confounding, and single-item measures. Female lifetime and current EC adolescent users (compared with lifetime EC abstainers) had significantly higher rates of all unhealthy weight control behaviors (lifetime EC use: aORs = 1.87–2.40, current EC use: aORs = 2.32–3.76), whereas male current EC users, but not lifetime users had significantly higher rates of all unhealthy weight control behaviors (aORs = 2.05–3.18). Similar associations were found for CC use.

In one weak-quality US university-based sample, EC use was not associated with binge-eating disorder. 74

Post-traumatic Stress Disorder

Two studies were found examining relationships between aspects of post-traumatic stress disorder and EC use. 74 , 80 Findings were mixed and quality of evidence was weak, both studies used cross-sectional designs, and there was risk of sampling bias and potential confounding. Among college students, EC use significantly related to post-traumatic stress disorder (likelihood ratio χ   2 = 13.0, p = .002, Cramer’s V = 0.064) in the primary unadjusted analysis, but not after controlling for covariates. 74 In a small sample of YA, self-reported history of childhood mistreatment directly related to lifetime EC use (β = 0.19, p = .02), but not current use, a relationship that subsequent analysis found fully mediated by negative urgency, a dimension of impulsivity reflecting the tendency to act rashly while distressed (β = 0.11, p = .04). 80

Externalizing Disorders

Externalizing disorders (composite).

Analyses of adolescents in the PATH study found externalizing symptoms significantly associated with EC use. 60–64 Evidence quality was weak to moderate. In cross-sectional analysis of baseline data, high-severity lifetime externalizing problems were similarly associated with lifetime EC (aOR = 1.5, 95% CI: 1.3–1.7, p < .05) and CC use (aOR = 1.5, 95% CI: 1.3–1.7, p < .05). 61 In a 1-year longitudinal analysis of baseline nicotine-naive adolescents, high past-year externalizing problems were significantly associated with initiation of EC use (aRRR = 2.78, 95% CI: 1.76–4.40, p < .05), with relative risk ratios not significantly different from initiation of dual use (aRRR = 2.23, 95% CI: 1.15–4.31, p < .05) and CC use (aRRR = 5.59, 95% CI: 2.63–11.90, p < .05). 60

One longitudinal analysis of baseline nicotine-naive YA participants in the PATH study (moderate-quality evidence) similarly found that high-severity lifetime externalizing symptoms predicted EC onset (aOR = 1.4, 95% CI: 1.1–1.7, p < .05) at 1-year follow-up. 62 The relationship between externalizing symptoms and CC onset was not significant among these YAs.

Attention-Deficit/Hyperactivity Disorder

Two studies examined longitudinal relationships between ADHD symptoms and EC use among US high school students. 72 , 81 Both were moderate in quality, utilizing longitudinal designs with minimal attrition over 12–18 months while adjusting for covariates. Both studies found that ADHD symptoms predicted subsequent EC use, but not CC use. In a California-based cohort, overall ADHD symptoms (aOR = 1.22, 95% CI: 1.04–1.42) and hyperactivity–impulsivity subscale symptoms (aOR = 1.26, 95% CI: 1.09–1.47), but not inattentive subscale symptoms predicted initiation of EC over 18-month follow-up. 72 Similarly, in a small study of college-bound seniors, using a cross-lagged path model, ADHD symptoms at Time 1 (T1) predicted EC use at Time 2 (β = 0.206, p < .001) and ADHD symptoms at Time 2 predicted EC use at Time 3 (β = 0.350, p < .001), but EC use frequency was not associated with subsequent ADHD symptoms. 81

In contrast to the findings of adolescent samples, two studies examined ADHD symptoms and EC use among college students, both finding no associations when controlling for covariates. 73 , 74 The quality of evidence was weak-moderate in strength, due to only one longitudinal design and self-report measures. In a cross-sectional study, ADHD symptoms were significantly associated with EC use status (likelihood ratio χ   2 = 16.778, p < .001, Cramer’s V = 0.073) in the primary unadjusted analysis, but there was no significant association when controlling for covariates. 74 In a 2-year longitudinal study, neither ADHD nor any other psychological factors measured predicted EC use after controlling for covariates. 73

Conduct Disorder and Delinquency

Three articles examined conduct disorder symptoms and found significant relationships with subsequent EC use. 64 , 72 , 82 All were moderate-quality longitudinal studies, and two were nationally representative (United States, United Kingdom). An analysis of baseline nicotine-naive adolescents in the PATH study found that baseline rule-breaking tendency independently predicted EC use in the subsequent year (aOR = 1.93, 95% CI: 1.58–2.34). 64 Similarly, past 6-month delinquent behavior was associated with later EC use (aOR = 1.32, p < .001) and CC use (aOR = 1.41, p < .05) among a cohort of nicotine-naive US high school students. 72 Reports of various delinquent behaviors (eg, theft, vandalism, graffiti) were significantly higher for lifetime EC-only users (vs. never users) (aORs range 3.9–6.0, p < .001) but to less extent than among CC users and dual-EC and CC users (aORs range 5.7–11.9, p < .001). 82

Transdiagnostic Constructs

Impulsivity and executive function.

Impulsivity describes a predisposition toward rapid, unplanned actions without regard for long-term consequences and has been implicated in ADHD, conduct disorder, bipolar disorder, and personality disorders. 83 Executive function describes closely related capacities for planning, working memory, self-control, and attention shifting.

Adolescent:

Three studies examined impulsivity and EC use 71 , 84 , 85 and two studies among one cohort examined executive function. 86 , 87 These studies consistently found EC use related to impulsivity and executive function deficits. Overall, quality of evidence was weak, with nonprobability samples and cross-sectional designs.

In a cross-sectional analysis of California high school students, impulsivity was elevated similarly among EC and CC users. 71 In longitudinal analysis of British high school students, baseline impulsivity predicted onset of EC use (aOR = 1.263, 95% CI: 1.183–1.349) and CC use (aOR = 1.452, 95% CI: 1.286–1.638) at 24-month follow-up. 84 In a cross-sectional study using a mediation model, impulsivity was associated with more frequent EC use through an early age of EC initiation. 85

In a cross-sectional study of 12-year-old children in California, lifetime EC use was strongly associated with executive function deficits (aOR = 4.99, 95% CI: 1.80–13.96, p < .01), 86 with subsequent analysis finding the relationship between low inhibitory control and EC use most applicable among low-socioeconomic status respondents. 87

Four studies, also weak in overall quality, investigating EC use and various subcomponents of impulsivity (eg, sensation seeking, negative urgency, lack of premeditation, and perseverance) have had mixed results, with studies most consistently supporting a relationship between sensation seeking and EC use. 21 , 80 , 88 , 89 Two longitudinal studies 88 , 89 found relationships between sensation seeking and subsequent EC use (eg, ever JUUL use: aOR = 1.76, 95% CI: 1.52–2.05, p < .01; current use: aOR = 2.16, 95% CI: 1.81–2.58, p < .01), 89 and one cross-sectional study 80 found a correlation between sensation seeking and EC use, although relationships with other subcomponents of impulsivity were generally not significant (one small study found significance for negative urgency 80 ). One study found lack of perseverance predicted CC use (aOR = 1.52, 95% CI: 1.11–2.07, p < .05), but not EC use at 1-year follow-up. 21 In addition, in a cross-sectional study assessing impulse control disorders, EC use was related to gambling disorder (likelihood ratio χ   2 = 37.2, p = .000, Cramer’s V = 0.081), but not other impulse control disorders. 74

Perceived Stress

Perceived stress describes a heritable tendency to deem negative events as unpredictable and uncontrollable and has been implicated in anhedonic depression, anxious dysthymia, psychosis, post-traumatic stress, and various personality disorders. 90

One moderate-quality study assessed perceived stress in adolescents. 90 In a 4-year longitudinal follow-up of California teenagers, baseline (age 13) perceived stress was associated with lifetime and past-month EC use (aOR = 1.25, 95% CI: 1.07–1.47, p < .01) at age 17 as well as lifetime and past-month CC use (aOR = 1.32, 95% CI = 1.08–1.61, p < .01).

One study, weak, limited by cross-sectional design, assessed past-week perceived stress among college students, finding perceived stress associated with past 30-day EC use (aOR = 1.03, 95% CI: 1.00–1.05, p = .03) and CC use (aOR = 1.02, 95% CI: 1.00–1.04, p = .04).

Forty existing studies assess mental health comorbidities of EC use among AYA. This review of the current evidence, the first on this topic, summarizes our current knowledge base and facilitates future investigation.

Among adolescent studies, EC use is associated with internalizing problems, depression, suicidality, disordered eating, externalizing problems, ADHD, conduct disorder, impulsivity, and perceived stress, with additional limited evidence for an association with anxiety. These findings largely align with prior findings regarding mental health and CC use. 26 , 27 , 91–93 Among YA specifically, EC use has been associated with internalizing problems, externalizing problems, depression, sensation seeking, and perceived stress, whereas existing evidence does not support relationships with ADHD or anxiety.

The finding that ADHD was associated with EC use among adolescents but not YA may reflect methodological differences. Alternatively, ADHD may represent a risk factor for EC initiation among adolescents that becomes attenuated by young adulthood, due to neurobiological and psychosocial factors. Given well-established risks for substance use among AYA with untreated ADHD, 94 adolescents may gravitate toward ECs, influenced by social media 95 and availability, 96 whereas YA tend toward other substances (eg, alcohol). Brain maturation and resulting improvements in self-regulation, may also contribute to the observed difference.

Most adolescent cohorts (6/7), but only half of YA cohorts (3/6) found relationships between EC use and depression. Most of the adolescent studies were national cohorts, versus university-based samples in YA studies, and some adolescent studies used single-item measures for past-year depressive episodes. 66 , 69 These methodological differences may underly the difference in findings. Alternatively, the clear association in adults between depression and alcohol and substance use 97 again supports the hypothesis that depressed adolescents may turn to ECs whereas YAs access other substances.

Findings were similar for both EC and CC with a few notable exceptions. ADHD predicted onset of EC use but not CC use among adolescents. 72 , 81 This difference may reflect the role of sensation seeking in EC use, as youth with ADHD may be particularly attracted to their novel flavors. Although minimal associations were found between EC use and anxiety, associations were somewhat stronger for CC use and anxiety among adolescents and YA. 71 , 73 Externalizing symptoms were more strongly associated with onset of CC use than EC use among adolescents, 60 but not YA. 65 Adolescents with conduct problems may view CC use as a greater act of rebellion and risk-taking, given longstanding regulations against CC use, which have only recently begun for EC. Among YA, many high externalizing respondents were probably excluded for prior nicotine use, 62 so the negative finding may reflect that high externalizing youth had an earlier age of onset.

Implications for Practice

Clinicians should have a low threshold for providing mental health screening and referrals when treating youth using EC, as EC use may be an indicator of behavioral health risk. At this time, it seems reasonable to counsel AYA with depression and other mental health problems against vaping, warning that vaping and other substance use may exacerbate their mental illness. Although the longitudinal evidence linking vaping to subsequent psychopathology remains limited, there is some evidence of a relationship, 70 which would be consistent with relationships between CC use and mental illness, 98 and with existing models of nicotine and neurodevelopment (as described in the introduction). In addition, it is important to emphasize vaping cessation in AYA with mental illness to prevent potential progression to CC and other substance use 20–23 and associated long-term health sequelae, 24 which disproportionately affect adults with mental illness.

Further research is needed to better understand how comorbid mental illness influences uptake, use patterns, and cessation among AYA with mental illness to appropriately counsel and treat this population. There are no known effective treatments for youth EC cessation. Although EC manufacturers have created “curricula” to reduce underage abuse, these have many limitations. 99 Parents and school administrators struggle in implementing restrictions to curb use. 100 , 101 Although there exists a need for additional studies to enlarge the evidence base for adolescent CC smoking cessation, existing evidence best supports group-based behavioral interventions. 102 Adapting these programs to EC use may be effective alongside policies targeting specific problematic practices in EC marketing. 103 However, in developing interventions to mitigate EC use, it will also be important to monitor for the possible unintended consequence of diverting youth toward other, potentially riskier, substances. The results of this review highlight the importance of interventions to take into account AYA with mental illness as a special vulnerable population, which may benefit from tailored practices on both the intervention and public health policy levels.

Limitations of Evidence and Directions for Further Research

The quality of evidence among included studies varied, with several consistent limitations. The young adult studies were largely among college-based samples, raising the risk of selection bias. Given high prevalence of EC use among other groups of YA, 53 further study of high-risk YAs remains warranted. In addition, few studies have adjusted for use of other substances (see Supplementary Table 1 ), despite high comorbidity between vaping and other substance use 43 and the potential impacts of other substance use on mental health. Most studies that included substance use as a covariate still found significant relationships between EC use and mental health comorbidities. 57 , 60 , 70 , 78 , 82

Most studies were cross-sectional, or longitudinal studies with short-term follow-up. As a result, important questions about the impact of EC use on the trajectory of mental health symptoms remain unanswered. One study presented data to support a bidirectional relationship, 70 whereas two found no evidence for EC affecting subsequent mental health. 76 , 81 Given that EC use may alter cognitive and emotional health through multiple pathways, 13 further longitudinal studies remain important.

Future studies should develop more nuanced measures of EC use and establish their validity and reliability. Most studies measured either lifetime use or current use by self-report. Factors such as frequency and patterns of use, dose of nicotine (which varies considerably among products), and nicotine dependence remain relatively uninvestigated and will be important to identifying factors of youth most at risk of adverse outcomes. In addition, most studies relied on mental health screening measures, which were not designed to be diagnostic.

We expect EC use to remain an active area of investigation, given evolving legal restrictions on EC use and changing youth behavioral trends. Although youth vape numerous substances, we only found a few studies assessing vaping of cannabis and illicit drugs. In the United States, the rise of ECs over the past decade has coincided with loosening of restrictions on cannabis use. 104 Although studies indicate nicotine remains the main psychoactive substance inhaled by AYA EC users, use of cannabis in ECs is not inconsequential. 12 Like nicotine, cannabis use during adolescence influences development of depression and psychosis. 105 , 106

Although we found studies examining EC use across a range of psychopathology, we found no studies assessing psychosis. Given high rates of nicotine-associated long-term mortality and the potential etiologic role of nicotine in development of psychosis, 41 this subgroup may be most at risk of long-term adverse outcomes from EC addiction, and thus most in need of early intervention.

Limitations of Review

We acknowledge several limitations of this review. We defined inclusion criteria broadly to permit a wider view of the existing literature, but one which precluded quantitative meta-analysis, since each subcategory of results ultimately includes only a few studies, using a variety of mental health measures and covariates (see Supplementary Table 1 ). We anticipate this review will provide a horizon to permit future systematic studies to evaluate narrower questions. We excluded studies focused only on substance use disorder comorbidities, an important topic needing a dedicated review. Although we included all internalizing and externalizing mental health conditions and transdiagnostic concepts reported in this literature, we did not include search terms for transdiagnostic concepts. Our review yielded mostly US-based studies, which may in part reflect our exclusion of non-English studies; thus, it is not clear to what extent results generalize to other settings.

We identified 40 recent articles investigating the relationship between mental health and EC use among AYA. EC use correlates with several domains of AYA mental health problems. Much remains unknown about the particular use patterns of high-risk youth and the long-term neuropsychiatric sequelae of EC use during AYA development. Given the elevated rates of EC use among AYA with mental health problems, further research remains warranted.

A Contributorship Form detailing each author’s specific involvement with this content, as well as any supplementary data, are available online at https://academic.oup.com/ntr .

This research was not supported by external funding.

None declared.

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• comorbidity
• mental health
• young adult
• electronic cigarettes

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• Research article
• Open access
• Published: 15 October 2020

Motivations for use, identity and the vaper subculture: a qualitative study of the experiences of Western Australian vapers

• Kahlia McCausland   ORCID: orcid.org/0000-0001-7071-6491 1 ,
• Jonine Jancey 1 ,
• Tama Leaver 2 ,
• Katharina Wolf 3 ,
• Becky Freeman 4 &
• Bruce Maycock 1 , 5  

BMC Public Health volume  20 , Article number:  1552 ( 2020 ) Cite this article

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Vaping is a relatively new practice, and therefore its symbolic meanings and social practices are yet to be fully understood, especially within Australia where the practice is strictly regulated. This study aimed to examine vapers motivations for use, reinforcing influences, and association with the vaper subculture.

Working from a constructivist epistemology and a symbolic interaction framework, in-depth interviews were conducted with a purposive sample of 37 current (89%) and former (11%) adult vapers, 70% male, mean age of 32.5. Data was analysed via thematic analysis.

Vapers largely started vaping to quit smoking and underwent common experiences during their initiation phase. Subsequently, vapers tended to adopt one of two dominant identities, that of the ‘cloud chaser’ or the ‘substitute’, which some users moved between during different stages of their vaping career. The social and symbolic meaning of e-cigarettes and vaping varied and involved concepts of harm reduction, addiction, pleasure, stigma and community, and for some, connection to the vaper subculture.

Conclusions

Understanding the complexities of vaping, and the nuanced differences of ‘cloud chasers’ and ‘substitute’ vapers may have important implications for health communication, research and policy. E-cigarette users within this sample were not a homogeneous group and differed in their motivations for use, association with the vaper subculture and relationship with the vape community. These findings provide new insights into the socialisation process and subsequent identity adoption of vapers within the unique regulatory environment of Western Australia.

Peer Review reports

Since entering the American market in 2007 [ 1 ], e-cigarettes have undergone a rapid evolution, with three broad classifications of vaping devices now recognised i) disposable (cig-a-like), ii) closed reusable (vape pen, pod-based), and iii) open reusable (mod) [ 2 ]. Cig-a-likes closely resemble a cigarette with a glowing tip that lights up upon inhalation and is disposed of once the e-liquid is consumed. Closed reusable systems use replaceable pre-filled cartridges which tend to be limited in functionality (i.e. inability to adjust the temperature) and were originally designed to resemble cigarettes. However, the most recent generation of closed reusable vaping devices, pod-based systems, have diverged from cigarettes and now resemble USB sticks [ 2 ]. Finally, open reusable systems comprise a refillable liquid reservoir or ‘tank’, which users fill with their preferred choice of e-liquid.

E-cigarettes were originally developed as an alternative form of nicotine delivery and potential smoking cessation device [ 3 ]. However, over the short period since their inception, they have transformed into high-tech nicotine delivery devices appealing to both non-smokers and youth [ 4 ], an outcome largely stemming from increased investment by the tobacco industry [ 5 ]. This investment has contributed to their use moving beyond their touted role as a nicotine replacement and tobacco cessation device, to a social, recreational and sensory delivery device [ 6 ] associated with new rituals and social practices [ 7 ].

Smokers cite numerous reasons for starting vaping, these include: to ease nicotine cravings and withdrawal symptoms; to quit smoking or avoid relapse; to use e-cigarettes where smoking is prohibited; reduce cost; and the belief that e-cigarettes are less harmful than tobacco [ 8 , 9 , 10 , 11 ]. However, recently, research has investigated the rise in ‘alternative’ e-cigarette use behaviours such as dripping (i.e. applying e-liquid directly on the atomiser) [ 12 ] and vape tricks (i.e. creating shapes from exhaled aerosol) [ 12 , 13 ] which may contribute to the perception that e-cigarettes are ‘cool’ or to be used for recreation [ 13 ].

Research from Europe has explored e-cigarette user’s motivations, self-identity as vapers and involvement in vaping subcultures. Farrimond [ 14 ] identified differing motivations for use of, and varying political engagement in, vaping regimes among a sample of vapers in the United Kingdom (UK) and constructed three main typologies to describe these users: vaping for pleasure, vaping as medical treatment and ambivalent e-cigarette use, suggesting that the motives of vaping may be linked to different social identities. Similarly, a study of Norwegian vapers identified two dominant vaper identities, who Tokle and Pedersen [ 15 ] labelled ‘cloud chasers’ and ‘substitutes’. Cloud chasers were dedicated vapers who identified with symbols and values in the subculture, many of whom were politically engaged in improving e-cigarette regulation, describing a sense of belonging to the vape community. Whereas substitute vapers were former daily smokers who used e-cigarettes for smoking cessation, to improve their health, escape the stigma of smoking and manage nicotine addiction. These studies echo other international research pointing to the symbolic and identity aspects of vaping [ 16 , 17 , 18 , 19 ].

Vaping is a relatively new practice, and therefore its symbolic meanings and social practices are yet to be fully understood. However, it appears that through the uptake of vaping, personal and collective identities have been established and a vaping subculture has emerged [ 14 , 15 , 20 ]. Considering the limited extant research investigating e-cigarette use within Australia, this study aimed to examine vapers motivations for use, reinforcing influences, and association with the vaper subculture within Western Australia.

In Australia, liquid nicotine is classified as a ‘Schedule 7-Dangerous Poison’ under the Federal Poisons Standard [ 21 ]. Hence, the only legal avenue for obtaining it is through a personal importation scheme [ 21 ], which states the user must have a prescription from a physician. E-cigarettes that do not contain nicotine can be sold in some Australian jurisdictions, provided manufacturers do not make therapeutic claims. However, in Western Australia, the context of this study, it is currently an offence under the Tobacco Products Control Act 2006 [ 22 ] to sell products that resemble tobacco products, regardless of whether they contain nicotine or not.

Since the early 1990s, Governments in Australia have enacted progressive comprehensive legislation to reduce the impact of tobacco [ 23 ], and as a result, smoking rates have steadily declined. The 2019 National Drug Strategy Household Survey (NDSHS) [ 24 ] reports daily tobacco smoking rates in Australia have more than halved (11.0%) since 1991 (24.3%), and the daily use of tobacco products is most common among people aged 40–59 years (31.7%). Conversely, e-cigarette use has increased and current use is most common among those aged 18–29 (32.4%). During the time this study was undertaken the number of vape retail stores within the Greater Capital City Statistical Area (GCCSA) of Perth, Western Australia, had multiplied exponentially [ 25 ], which has resulted in increased exposure and access to these products, and perhaps reflects an increase in demand.

Vaping devices are referred to by users and scholars by a multitude of terms, including e-cigarette, ENDS (electronic nicotine delivery device), vape and mod. In this paper, the term e-cigarette is used to represent all of the various consumer products available.

Theoretical framework

Symbolic interactionism is a micro-level sociological theory providing the theoretical framework underpinning this study [ 26 ]. Symbolic interactionism is situated in a constructivist epistemology, focussing on the interactions between individuals rather than large scale social structures, examining how people navigate their interactions with others and allocate meanings based on their interpretation of those interactions [ 26 , 27 ]. Symbolic interactionism has a history of being used to investigate drug use, the creation of deviance, and the exploration of meaning associated with new phenomena [ 28 , 29 , 30 ]. The symbolic interaction framework, therefore, assists in understanding a society (e-cigarette users) which is created through the repeated interactions between vapers [ 26 , 27 ].

Participants were purposively sampled for maximum variation in demographic characteristics (i.e. sex, age, Index of Relative Socio-Economic Advantage and Disadvantage (IRSAD) - a ranking derived from the economic and social conditions of people and households within an area [ 31 ]) within the sampling frame. Data collection and analysis occurred simultaneously (March – November 2018), facilitating appropriate and targeted recruitment. Eligible participants were current and former (vaped within the last 12 months) vapers, aged over 18 years residing within the GCCSA of Perth, Western Australia [ 32 ]. Eligibility criteria were stipulated on all recruitment material.

Recruitment

A multipronged approach to recruit participants was utilised. Recruitment flyers and posts were placed on four online vaping forums (AussieVapers, Vaping in Australia, Vaper Café Australia and E-Cigarette Forum); seven subreddits on Reddit; and 30 closed vaping Facebook groups. The lead author created personal accounts on each of the forums and social media. Facebook groups were accessed by requesting permission to enter the group as a researcher to recruit study participants. Vape retail stores, online and bricks and mortar, within the GCCSA of Perth were contacted via email, social media and webpage submission forms. Snowball sampling was also utilised.

Interested individuals were invited to contact the lead author via email or telephone to express their interest in participating and receive further details about the project and what their participation entailed. After reading the participant information statement and providing informed consent, interviews were arranged at convenient safe public locations (e.g. local café, university campus). Interviews were conducted in English by the lead author who has experience in qualitative data collection. Interviews lasted on average 49 min (range 25–86 min) and were audio-recorded with participant consent. Participants were provided with an AUD$25 gift voucher at completion of the interview as an honorarium for their time.

Data collection

A semi-structured interview guide was developed to allow flexibly and adaptability within each interview [ 33 ], and pilot tested with two participants. The interview guide addressed the following topic areas: reasons for vaping; pathway to using; knowledge, attitudes, and beliefs associated with e-cigarette use; devices and products used; means of accessing products; attitudes of friends, family and society towards vaping and their use; and emergent subculture (see Additional file  1 ). As new ideas and concepts were identified within the data these data-driven concepts were fed back into the data collection process and further guided sampling and adaption of the interview guide [ 34 ]. Sampling was terminated when thematic saturation was reached [ 35 ], which was determined through the constant comparison of data with preceding data until few new themes were generated.

Analysis and interpretation

All interviews except one (file corrupt) were transcribed verbatim by an independent professional transcription service and checked for accuracy by the lead author. The detailed notes taken by the lead author during and after interviews were sent via email to the participant the following day to review for accuracy and validation. Amendments from the participant were returned via email. Transcripts and interpretations were not provided to participants for respondent validation. Interview transcripts and detailed notes were anonymised and imported into NVivo (v12) to facilitate data organisation and linkage. The lead author conducted all coding, allowing for a single researcher to be immersed in both the data collection and analysis, thereby ensuring that the coding frame adequately described the intentions and content of the interviews [ 36 ].

The analytical process followed the steps proposed by Braun and Clarke [ 37 ] for thematic analysis and drew upon the initial and axial coding process of grounded theory [ 38 ]. The lead author played an active role in the analysis by searching for and identifying themes “to theorize the sociocultural contexts, and structural conditions, that enable the individual accounts that are provided” [ 37 ] (p. 85). Line-by-line analysis was undertaken to look for patterns of meaning and issues of interest important to the research objective and to generate a range of initial codes [ 38 ]. Codes were developed based on theoretical interest and emergent concepts that arose during interaction with and interpretation of the data. Axial coding examined the initial codes at a conceptual level to combine and connect codes to form overarching ‘candidate’ themes and subthemes in a meaningful way for the phenomenon under investigation [ 38 ]. Revision of the candidate themes then occurred at two levels. Level one involved reviewing all the data collated under each candidate theme to consider whether the data formed an intelligible pattern [ 37 ]. Some themes and sub-themes were refined during this process to create new themes/subthemes and to separate and combine others [ 37 ]. Level two involved a similar process, whereby the data were reviewed and further refined. This process, however, concerned the validity of the individual themes in relation to the data set ensuring participants meanings and voices were accurately reflected [ 37 ]. A detailed analysis was then written for each theme to report the content and meaning of patterns [ 37 ]. Working theme titles were reviewed to ensure they accurately reflected the respective analysis and the most vivid quotes were selected that best illustrated the essence of the point being described [ 37 ].

Strategies to enhance the rigour of the research included the use of a codebook to provide structure and agreement about code definitions, constructs, and themes; in-depth rich description of the research methods through field notes, personal reflections and analytic memos [ 39 ]; and discussions with team members about meaning and interpretation of findings and conceptual maps [ 40 ].

Demographic and behavioural data were analysed using descriptive statistics (SPSS v26). The reporting of this study is guided by the consolidated criteria for reporting qualitative research (COREQ) checklist [ 41 ] (see Additional file  2 ).

Participants

Thirty-seven interviews were conducted with current ( n  = 33, 89%) and former vapers ( n  = 4, 11%) (Table  1 ), with a mean of age of 32.5 ( SD  = 7.411, range 20–45 years). Thirty-two participants (87%) were current or former cigarette smokers and five (13%) were vaping despite having never been a regular smoker. Five participants were dual users of tobacco and e-cigarettes. Former ( n  = 24, 65%) and current ( n  = 8, 22%) smokers had been using tobacco on average for 14 years ( SD  = 8.268, range 3–38 years). In comparison, participants had been vaping on average for 2.4 years ( SD  = 2.011, range 1 month – 7 years).

Two identities and approaches to vaping emerged from the data, which we labelled ‘substitute’ vapers and ‘cloud chasers’ after the dominant vaper identities constructed by Tokle and Pedersen [ 15 ]. Cloud chasing is the act of expelling large amounts of vapour using an e-cigarette, we use the term in a broader, more symbolic sense. As such, the ‘cloud chaser’ identity is formed by the experiences articulated by 19 dedicated vapers who connect with at least some aspect of the vaper subculture, whether that be engaging with hobbyist activities, the trick culture or technological aspects of vaping. Whereas the experiences of the ‘substitute’ vaper are derived from 18 vapers who primarily viewed vaping as a means to manage their nicotine addiction and quit smoking. The identity prescribed to each user was not ‘fixed’ as some participants described their movement between the two identities over time as the meaning they attributed to vaping changed (i.e. hobby to primarily smoking cessation).

The narrative summary describes the commonalities experienced by vapers and then the experiences unique to the ‘substitute’ and ‘cloud chaser’ identity. Quotes from participants are provided in italics, followed by their pseudonym, attributed identity and age.

The common experience

“can i have a go of that”: an introduction to vaping.

Participants were predominantly introduced to e-cigarettes through work colleagues, friends, and during their time abroad in locations where e-cigarettes were more readily available (e.g. the UK). For the majority of participants, this introduction marked the first occasion they had seen or heard about e-cigarettes. Subsequently, participants asked if they could “have a go on that” or the e-cigarette user suggested they try their vape. No one spoke of being pressured into trying their first e-cigarette with experimentation occurring spontaneously, either alone with the user or in the company of friends. Rarely did participants report communal experimentation where the vape was passed around to multiple people, rather it was most commonly a discrete encounter. Participants were mostly curious to try this device which in most instances functioned like a cigarette, however, were told it was not. Participants regularly reported coughing upon trying their first vape which could be attributed to several factors including the type of device (e.g. first/second versus third/fourth-generation device), device functionality (e.g. variable temperature, wattage, airflow or resistance), nicotine concentration, and the users smoking history, if any. Those who were smokers described this experience as being similar to that of their first drag of a cigarette, whereas non-smokers had difficulty articulating their experience as they had nothing to compare it to.

“As a non-smoker, it was really hard for me to grasp the concept. Everyone was trying to explain it to me like it's either like a cigarette or a bong. I was like, ‘I don't know what you're talking about.’ They were like, ‘mouth-to-lung, or direct-to-lung’ and I still can't even understand the concept. If I had to explain to you what I do, I don't know what I do. I press the trigger, I breathe it in, it comes out.” Karis, cloud chaser [ 33 ]

The inhalation of vapour reportedly took some time to get used to as the vapour from the e-cigarette was “moist” compared to the “dry heat” of a cigarette. Participants went on to purchase an e-cigarette for themselves after enjoying their first experience, or after disliking the encounter chose not to pursue it until another opportunity arose, years later in some instances.

“I was a silly teenager”: motivations for vaping

Thirty-two users were tobacco smokers for many years and described themselves as being “very addicted” which had resulted in several failed quit attempts. Participants had tried multiple methods to quit smoking, including going ‘cold turkey’, hypnotherapy, and nicotine replacement and drug therapies. The increasing cost of tobacco, real and feared deterioration of their health, and encouragement from loved ones to quit smoking were other significant drivers to commence and subsequently maintain vaping. For those users who had never been committed smokers, their motivations for initiating vaping were varied and included socialisation with other vapers, to appease food cravings, and as a diversion from alcohol or illicit drugs.

“On their way to their vaping journey”: starting off

Most participants opted to start their “vaping journey” with a disposable (cig-a-like) or pen-style closed-system device which introduced them to vaping at a rudimentary level, as explained by River [ 42 ] “… something basic, where you push the button, you suck on it…” . Most, however, described these devices as unsatisfying (e.g. mute flavour, inadequate throat hit), poorly fabricated and not producing enough vapour. Subsequently, most participants progressed to an open-system device which provided functionalities to enhance and personalise their flavour profile, adjust temperature, voltage, resistance, airflow and nicotine concentration, and comprised a refillable tank and rechargeable batteries. These features were particularly important for tobacco smoking participants, and were conducive to replicating the “throat hit” they were accustomed to.

“It [e-liquid] had no nicotine in it, as is Australian rules. I ended up actually putting my own [nicotine] in it because it was just, too smooth basically, you could taste it, but you couldn't feel it which is what I want, I want to feel it [throat hit].” Brody, substitute [ 34 ]

Transitioning to vaping from “analogue cigarettes” was a daunting process for some, and more so for those who had never been committed smokers. Participants explained that other vapers had tried to describe to them how they were required to inhale to achieve the desired throat hit and experience the best flavour.

“My friends were kind of just like, ‘Just pull it in. You'll cough if you do it hesitantly.’ I was super scared of just going-- [inhales], on this thing that's firing. The first few times that I did it, I don't think I was doing it properly because I was firing it for a really short amount of time, taking like really small puffs. Then when I did do it properly, I was like, oh this is what it's meant to feel like and taste like." Karina, substitute [ 24 ]

For those who were smokers, they described the inherent challenges, actions and processes of transitioning from cigarettes to e-cigarettes which took perseverance, including no longer lighting a cigarette, maintaining a charged device, importing, mixing and storing liquid nicotine, and accepting the physicality of the device compared to the slender profile of a cigarette.

“Filling it up, charging it up, carrying it around, because it f***ing weighs a ton, as well. It just became too hard filling it up. It was always leaking, and it's not as simple as clicking a button and smoking it. You have to set it to what you want and all that.” Jonathan, substitute [ 27 ]

“A bit of a learning curve”: gaining knowledge and understanding

The majority of users reported being proactive in conducting intensive ‘self-learning’ through the internet and social networking platforms, other vapers, and to a lesser extent, retail stores, to acquire relevant skills (i.e. nicotine strength, mixing and safety; steeping; inhalation style “direct-to-lung” or “mouth-to-lung” ; building and changing coils), information on health and safety, the meaning of vaping specific language and jargon, and troubleshooting techniques. Vape forums, social media (i.e. Facebook) and content sharing platforms (i.e. YouTube) were usually the first resources accessed to acquire knowledge and support. Participants reported simultaneous active (i.e., contributing content) and passive (i.e., viewing content posted) engagement in multiple local and international vaping groups and forums to discuss personal experiences, exchange information, and obtain new knowledge. Passive engagement provided newcomers with an opportunity to observe the online community and its rules, whereas more established vapers kept their “finger on the pulse” by monitoring the rise of new products. Conversely, active contribution to these fora provided opportunities for learning among ‘newbies’ and mentorship for more experienced vapers.

“Well, that's where I got most of my knowledge from [online vaping groups]. It's hard to explain, it's a little family sort of thing, like whether it's starting off fresh or you know plenty of s**t you can always go there, get the advice that you need. That's definitely a helpful thing as well. … You've got people in those groups that have been vaping for 10 or so years, like starting off when it was just a tiny industry, a fresh industry. Then you've got people that are trying to get off the smokes and they ask for advice from there.” Timothy, cloud chaser [ 20 ]

“There is something for everyone”: finding the right product

During the transition phase from cigarettes to vaping, some respondents reportedly struggled to quit smoking, relapsing on occasion, and/or dual using with cigarettes until they found the right combination of flavour, nicotine concentration and device. Finding the right combination was the moment many sensed they could quit smoking, citing the sophisticated features of the second (closed reusable) and third-generation (open reusable) devices most effective for smoking cessation.

“For me, it was getting used to the action but also … finding the right flavours and then it was getting the nicotine level right, then it was finding the right device that was going to satisfy my intake, my draw in and my exhale… I’d buy one and go, ‘Oh it’s a bit crap. I still want a cigarette. Why do I still want a cigarette?’ Then eventually I found another device which was a bit more powerful and I found flavours that I actually liked and so when I found that flavour I can tell you it was 48 hours between finding this particular flavour blend to when I had my last cigarette.” Ursula, cloud chaser [ 43 ]

“I haven’t quit I’ve upgraded”: from one addiction to another

Smoking cessation was viewed very differently to nicotine cessation, with the majority of users opting to continue using nicotine in their vapouriser to keep them from relapsing to cigarettes. Three of the five users who had never been committed smokers chose to use nicotine in their vapouriser after being introduced to it by a romantic partner or friend. All three users described themselves as not being addicted and that they could easily give it up if they tried. The end goal for many participants was not to be reliant on nicotine at all, and they explained how they were, or had, implemented strategies to reduce the concentration of nicotine they were using, such as alternating between nicotine and nicotine-free vapourisers and gradually tapering down the nicotine concentration. Four users had successfully quit smoking and were continuing to vape nicotine-free. Those users who were happy to continue to use nicotine in a “cleaner” and “healthier” form (e-cigarettes), or felt they were not ready to “wean” themselves off for fear of relapsing to smoking, recognised that they had completely transferred the behavioural and sensorimotor aspects of smoking to vaping. However, they believed because they were no longer smoking any potential ill-health inferred by vaping seemed inconsequential.

“As it stands, I have no intention of stopping [vaping] because whilst I'm using that [vapoursier] I have no intention to have a cigarette. That's how passionately I don't want to smoke again, but I'm not prepared to risk it at this time, but who knows? … Do you know what, I often think I probably do need to cut back a little bit and I think, well I'm not smoking?” Ursula, cloud chaser [ 43 ]

Previous cigarette users observed that vaping fit nicely into their routine, which was once occupied by cigarettes (i.e. driving, coffee). Vaping allowed them to continue to enjoy the social aspects of smoking (i.e. drinking alcohol) and to placate feelings of stress or anxiety.

“Yeah, I still make a point of, especially when I first quit, of keeping that routine of going outside to smoke, or vape, just so it felt a little bit more like I was having a cigarette. It wasn't such a drastic change. You know like straight after a meal or things like that, my trigger moments. I would still get up, keep it to that little bit of a routine. Get up, go outside, have my vape, go back inside.” Ella, substitute [ 41 ]

Socialising with other vapers and smokers was said to reinforce and maintain their use of e-cigarettes. Even amongst those who were never committed smokers and those who were now vaping nicotine-free.

“I’m not a smoker. I’m a vaper”: breaking free of tobacco

In general, users referred to their device as a vape, themselves as a vaper, and the practice as vaping. Some felt the term ‘e-cigarette’ too closely aligned with smoking discourse and supported associations with negative connotations of death and disease. Vape products were generally not considered to be tobacco products, especially with the evolution of vaping devices and how they no longer resembled a cigarette, as earlier generations had.

“They need to stop calling them e-cigarettes because they're not cigarettes. That s**ts me up the wall, they're not cigarettes.” Ian, cloud chaser [ 29 ]

Several users documented how they had experienced the “ignorance” of both smokers and non-vapers, and many seized the opportunity to “educate” these people. They highlighted the features which distinguished vaping from smoking, such as not containing tobacco and the production of vapour, not smoke, and the perceived positive changes to their health they had experienced since starting vaping, in the hope of reducing the stigma and the estrangement they felt.

“… people will say, ‘why don't you just smoke cigarettes?’ which I think is a strange thing to say. People just misunderstanding the health risks.” Julia, substitute [ 26 ]

For some, they could not escape their internalised feelings of smoking-related stigma, and as a result, avoided vaping in public.

“I generally try not to vape in public because it is not stealthy unless you're using a little stealthy device … People can see you a mile away, and I get really embarrassed. But I used to hide when I was a smoker as well. At least when I was a smoker I could hide in my car. Even with my vape, I get in my car and there's big clouds coming out.” Ursula, cloud chaser [ 43 ]

The substitute vaper

“a means to an end”: vaping to quit smoking.

For those ‘substitute’ vapers who were former smokers, they viewed their vaping experience as a practical means to quit smoking and valued the positive effect vaping had on their health and wallet. They were aware of the existence of more enthusiastic vapers, however, at the time did not associate with the vaper subculture as ‘cloud chasers’ did.

“I see people, and it's kind of a sport for them, they make big clouds … I don’t really buy into that. … It's not where my mindset is. For me, yeah it [vaping] really is a means to an end [nicotine/smoking cessation].” Ella, substitute [ 41 ]

“It’s just a revolving circle”: stigma

Although many acknowledged the stigma they had endured as a smoker in Western Australia, some vapers holding the ‘substitute’ identity now projected these same negative feelings to fellow vapers associated with the ‘cloud chasers’ subculture, perpetuating the circle of stigma.

“People think that people smoking vapes think they’re ‘cool’. Sitting in their car and they've got big clouds coming out of the car. Even I do it. When I see clouds like that I think, ‘You d***head. You think you’re cool vaping like that?’ … Like I’ve seen the way people blow out their clouds I’m like, ‘You’re one of these d***heads who’s overclocking the battery’ … .” Milo, substitute [ 36 ]

“It is not stealthy”: managing vaping in public

Vaping is notorious for producing large vapour clouds (although some products such as JUUL are very discrete), and as such some ‘substitute’ vapers spoke of how they disliked the attention vaping brought them from bystanders, and spent energy devising strategies to manage their e-cigarette use in discreet ways, such as vaping alone. This was especially pertinent for some young women:

“It is a bit showy because like there's a lot more vapour. I guess the only place in public that I do it and feel kind of safe is like just at the park when I'm taking a walk or something.” Karina, substitute [ 24 ]

The cloud chasers

“i’ve gone full enthusiast”: the vaper subculture.

This group of respondents shared the view that e-cigarettes are a healthier alternative to smoking, however, more importantly, vaping also offered social and symbolic functions not provided by “analogue cigarettes” .

Vaping was differentiated from smoking, with some describing it as a hobby, which at times could be all-consuming and expensive. Nevertheless, many genuinely enjoyed customising their experience through the collection of various flavoured liquids and coloured devices, experimenting with the creation of their own juices, engaging in the technological aspects of vaping and building accessories, such as coils.

“I play around with them [making coils], I do all my own, I build all the things, I use all the rebuildable stuff. So yeah, it has become a bit of a hobby, which is why I think it appeals to certain people, because it has that sort of community aspect where it becomes like a hobby … they all sort of get together…” Wade, cloud chaser [ 28 ]

A minority of vapers reported attending “build days” and “vape meets” where users got together to learn about Ohm’s law and battery safety, how to build coils, and to meet new people and socialise, as the Western Australian vape community was reportedly not as established as others in the Eastern States of Australia.

Participants commented on the various ‘types’ of vapers (i.e. hobbyist, flavourist) and ‘levels’ (i.e. novice, advanced user, expert, veteran) one could progress to. Participants categorised themselves by comparing their preferences and level of experience with others, which was influenced by various factors including vaping duration, type of device they were capable of safely using (regulated vs unregulated (no circuit board and runs directly off a battery)), possessing an online profile or presence, and experience in the retail industry.

“[I’m] close to the expert stage. An advanced user, I'd say. When you start using mechanical mods, that's when you're an advanced user.” Zadie, cloud chaser [ 27 ]

“I've gone full enthusiast … I want to have the experience. I'm also hoping to get a job in one of the vape shops in Perth because I'm really enthusiastic about health or being able to help people.” Quade, cloud chaser [ 24 ]

A small proportion of ‘cloud chasers’ were highly immersed in the vaping subculture and were actively involved in, or managed specialised vape groups, provided product reviews to YouTube, Instagram and Facebook, and some were even ‘sponsored’ by local or international e-cigarette brands to promote their products on social media. Relationships between these vapers and their sponsors were established by one of them contacting the other, usually through social media.

“I'm part of this group called Cloud Kings Australia. Cloud Kings are basically all over the world. There's a group of them in Sweden, Mexico, Germany, France, Amsterdam, mostly in Europe. We get sponsored by companies, get free product from those companies, and then we rep[resent] those companies.” Zadie, cloud chaser [ 27 ]

Few were also deeply entrenched in the vape trick culture:

“Absolutely, there's an absolute technique [to vape tricks]. We've got it down to a really fine art. There's names of [tor]nados that you can do like specialised ones and stuff like the DNA, the double, oh it’s crazy. So we go all out. Like you've got to wet the table, make it stick, and you've got to layer it. So we do layer upon layer upon layer of smoke. No one’s allowed to breathe. If you breathe, you're dead.” Clara, cloud chaser [ 33 ]

“Vaping brings people together”: for the cause and the community

The vape community, especially the online community, was described as “free of judgement” and provided for many a sense of connection and belonging. Participants described how their communication with like-minded vapers gave them the forum and permission to “nerd out” and voice their struggles and triumphs with a group who they felt would listen and be responsive, which some users did not feel they were able to do with their non-vaping friends and family. For those who were more experienced vapers, they felt it was important to give back to the community and chose to mentor new vapers through the initiation process.

“I'm in a lot of Australia-wide groups ... and it’s community-minded. … It's a way to quit smoking, sure, it's a health choice, but it's also a hobby for a lot of people, so I think these groups are both support networks and hobbyists. … I think it is important because there's nowhere else to get that support to quit smoking. For me that's what vaping is all about, it's about quitting smoking and staying off the cigarettes. … For people like myself who have tried everything … It is important for me to give back, so I give a lot of advice to people that say ‘Hey I don't know what to do.’ I try and give people the advice that I didn't get but also just making friends Australia-wide, getting to know people. It's awesome. It's a pretty cool community, yeah.” Ursula, cloud chaser [ 43 ]

Further, some participants had turned vaping into a business; were currently working, or aspiring to work in the retail industry; or were creating a social media presence (i.e. reviewing products, seeking sponsorship) for themselves. Some of these participants who were heavily involved in the online community and/or retail industry expressed frustration with the “childish” and “bitchy” behaviour displayed by some of the vape community online, especially among local and inter-state retailers. Instances of online users “dobbing” on people to the authorities who were selling nicotine and/or devices were described, as well as general unsocial behaviour as illustrated by one local business owner:

“They're [vape retailers] just very childish, … and because it's still quite a small community, everything's a personal attack against someone else. Like, if so and so were to have a sale and then he'd think that it was a direct attack on him. It is very clicky and very immature a lot of the time, I don't know why. I don't really bother doing much with Facebook groups because that’s just where it all is. When it's in-store and stuff and it's all very professional, everyone's very eager to help, it’s just everyone seems to become a keyboard warrior online.” Wade, cloud chaser [ 28 ]

Users who heavily invested in the culture or hobbyist ethos were inclined to perceive their device as an accessory, or a status symbol which was dependent on having the very latest and greatest device. For these vapers, vaping not only encompassed their passion and desire to help others quit smoking but their livelihood, which now strongly aligned with their core values.

“All my life I've had trouble [working] in retail because I have an ethical code where I can't sell something that I don't believe in and I believe 100% in the industry of vaping and what their motives are. I think it's good. It is entirely good and all the people that I've met who also promote it and stand behind it have good intentions, and their sole drive is to see people get well and stop smoking. We want to make smoking history just as much as the non-smokers. That's the thing … almost all vapers are reformed smokers…” Quade, cloud chaser [ 24 ]

The Australian NDSHS has been regularly conducted since 1985, and first provided limited data about e-cigarette use in 2013. Data from the most NDSHS [ 24 ] reports the most prevalent e-cigarette users are male current and former smokers, which is reflective of our sample population. Data does not distinguish whether users use nicotine in their vapourisers, nor what type of device they use. Enhanced surveillance and reporting of e-cigarette use within Australia would contribute to a deeper understanding of the population using e-cigarettes, the reasons for using and devices used among this cohort, and would assist policymakers to determine where public health efforts should be focussed.

Thirty-two vapers in this sample were committed smokers for several years and five participants were dual users of tobacco and e-cigarettes. The primary reason for initiating vaping was to quit smoking, citing less than optimal successes with other TGA (Therapeutics Goods Administration Footnote 1 ) approved smoking cessations aids, as also described by a sample of American vapers [ 44 ]. Vaping was considered more satisfying and therefore more supportive of successfully quitting smoking compared to other methods due to its similarity with conventional smoking, namely the inhale and exhale of vapour, nicotine hit, and the hand-to-mouth action, as also documented in other international research [ 16 , 18 , 43 ]. Furthermore, vaping does not expect one to relinquish the rituals and habits connected to smoking [ 45 ]. The conclusions surrounding the effectiveness of e-cigarettes as a smoking cessation aid and their harm reduction potential, however, are varied and depend on several factors, such as whether the smoker switches completely to e-cigarettes, becomes a dual user with cigarettes, and whether the user becomes a sustained and persistent vaper [ 42 ].

The majority of vapers in this sample were former smokers, however, several respondents had taken up the practice despite having never smoked. Understanding how vapers ‘make sense’ of their health practices [ 46 ] is required to understand the processes by which vapers make health behaviour choices, such as choosing to vape, so that appropriate tailored communication on the risks and benefits of e-cigarette use can be developed [ 47 ]. Limiting vaping uptake by non-smokers is essential and the supportive role Australia’s strict regulation plays in limiting this uptake and exposure to marketing is discernibly apparent when compared with vaping prevalence within countries with more liberal regulation (i.e. United States (US) [ 48 , 49 ] and UK [ 50 , 51 ]).

Participants within this study generally exhibited limited knowledge of the potential health effects of e-cigarettes. However, as reported by vapers abroad [ 52 , 53 ], they expressed many positive attitudes towards e-cigarettes, held very strong opinions that vaping offered them an alternative means to consume nicotine, and based their decision to use e-cigarettes on perceived harm reduction compared to cigarettes. For them, the individual health benefits experienced and the tangible sense of satisfaction since ceasing smoking outweighed the potential health risks of maintaining vaping. Furthermore, continued nicotine addiction was largely perceived as unproblematic so long as it helped maintain a cigarette-free lifestyle, also documented by others [ 43 , 54 ]. This concept has been studied by Oakes and Chapman [ 55 ] who explored the rationalisations smokers use to explain their justification of continued smoking and suggest a series of self-exempting beliefs may provide smokers with a false sense of security and ultimately block them from exploring the importance of quitting. Given the complexity of nicotine and addiction, and the assortment of information presented on e-cigarettes, it is not unexpected that users in this study and overseas [ 56 ] rely on their own experiences, and that of others, to inform their behaviour and decision-making processes [ 18 ]. This highlights the need for accessible, clear and impartial information about e-cigarette use which communicates the benefits, risks and current uncertainties to health professionals and the public about e-cigarettes [ 43 ] and continued support for nicotine cessation through approved cessation methods.

Participants mostly described positive reactions from friends and family to their e-cigarette use, particularly when their goal was to abstain from smoking. In this sample of vapers, few had close friends who vaped and therefore sought camaraderie through online fora and vape retail stores. As found in other qualitative inquires [ 16 ], the notion of a vaping community was recurrent. However, participating in a community that accepts the practice may make it difficult for individuals to quit and therefore contribute to sustained use [ 57 ]. These findings suggest that social norms surrounding e-cigarette use have a potentially powerful influence on initiation and maintenance and that understanding social networks is integral to prevention efforts.

Although tobacco smoking is legal in Australia, the decline in prevalence combined with the denormalisation of smoking and societal aversion has fated the behaviour to be predominantly relocated to the fringes of society and viewed as a deviant and marginalised behaviour [ 58 ]. For some smokers in this study, feeling stigmatised for being a tobacco smoker was the catalyst for them to redefine themselves as ‘vapers’, as supported by findings from Barbeau and Burda [ 16 ], making the language used (i.e. not referring to vaporises as e-cigarettes) incredibly important in an attempt to escape the stigma attached to cigarette smoking [ 44 ]. This redefinition and transition from smoker to non-smoker has been argued to play a key role in supporting successful smoking cessation [ 59 ]. However, through the quest to obtain the socially desirable non-smoker status, smokers have adopted another behaviour that maintains addiction and deviates from current societal norms, an unapproved and unconventional means to quit smoking.

Two approaches to vaping emerged from our data, that of the ‘cloud chaser’ and the ‘substitute’. Vapers within this sample displayed similar subcultural elements and practices to those reported in the international literature examining the motivations of e-cigarette users, identity formation and involvement in the vaping subculture [ 14 , 15 ] which could be diffused via global structures such as social media. However, some subcultural elements are localised to Australian vapers due to the unique social conditions under which the behaviour has evolved. For example, the vaping subculture which has emerged in the US is more encompassing than in Australia, which may be attributed to differences in the countries regulatory contexts [ 60 ], access to nicotine products, and exposure to mass marketing [ 61 ] and subcultural practices (e.g. vaping conventions [ 62 ] and abundant vape stores [ 63 ]).

Supported by Farrimond [ 14 ] and McQueen and Tower [ 64 ], ‘cloud chasers’ perceived their affiliation and connection with the vape community in the online and offline milieu as a positive source of support and reinforcement. Moreover, vaping was regarded as an integral part of their social identity, influencing how they behaved and the social and political activities they engaged in. Given the loss of identity and social engagement reported by individuals who quit smoking, the social opportunities, and group and community experience of vaping may be a particularly appealing aspect of the endeavour [ 6 , 16 , 53 ]. Furthermore, vaping was explicitly differentiated from cigarette smoking and referred to by many ‘cloud chasers’ as a hobby. Several dimensions of ‘pleasure’ were identified, including the sensory experience (i.e. flavours) and electronic and technological aspects of vaping [ 6 , 65 ]. Such descriptions of enjoyment are not usual in the substance-use discourse [ 66 ] due to the dominance of the ‘pathology paradigm’ which marginalises the idea of pleasure concerning drug use [ 67 ].

The assessment that e-cigarettes are a tool to manage nicotine addiction among ‘substitute’ vapers may explain why these users did not strongly identify with, or actively rejected connection with the social identity of vaping, and enjoyment did not play a substantive role in their use and maintenance [ 14 ]. Research suggests that cessation goal-oriented vapers may be less likely to become persistent e-cigarette users compared with vapers who do not stipulate future intentions to quit [ 68 , 69 ]. The nuanced differences in experiences of ‘cloud chasers’ and ‘substitute’ vapers may, therefore, contribute important insights for health communication. Australia has implemented a suite of effective strategies [ 23 ] to combat tobacco smoking that could be applied to e-cigarettes, such as supplementing health communications with legislation (e.g. health warnings, plain packaging, smoke-free laws that include e-cigarette use), until there is scientific evidence regarding their safety and efficacy as a tobacco cessation therapy [ 70 ].

E-cigarettes are both technically complex devices, which novice users may find difficult to spontaneously start, and a non-medical consumer product, which has resulted in the need for many aspiring users to look to other vapers as their experts, building a vast and international social network of shared knowledge and identity [ 14 ]. A common experience among this cohort of vapers was their use of e-cigarette forums and social media groups to discuss personal experiences, exchange information, and obtain new knowledge, similarily reported by vapers in New Zealand [ 18 ]. Seasoned vapers and newcomers disclosed periods of both active and passive engagement (also known as ‘lurking’ [ 71 ]). Lurking served newcomers with an opportunity to observe the community and its rules [ 72 ], whilst it provided more established vapers with the opportunity to monitor changes in the industry and the development of new products. Conversely, active contribution to these fora provided opportunities for learning among ‘newbies’ and mentorship for more experienced vapers. Some research suggests that joining and actively participating in e-cigarette-related social media communities [ 13 , 73 , 74 ] may play an important role in the development of ones vaping identity [ 14 , 18 ] and can exert a significant influence on attitudes and behavioural intentions toward e-cigarettes [ 75 ]. The investigation of dedicated vaping fora, therefore, may be valuable to study interactions among users and how these interactions shape e-cigarette knowledge, attitudes and behaviours.

These findings were gathered from a small purposive sample within a specific geographical context and time, and therefore may not be generalisable to the broader vaping community or e-cigarette users abroad due to Australia’s regulatory environment, absence of mass media advertising and lack of Government endorsement as a smoking cessation aid [ 76 ]. However, the consistency with other research suggests our findings are not atypical. All participants in this study were adults, therefore these results may not be generalisable to younger vapers.

Few studies have explored vapers motivations for use, reinforcing influences, and association with the vaper subculture, especially within the unique regulatory context of Australia. We found that our sample of vapers largely started vaping to quit smoking and underwent common experiences during their initiation phase. Subsequently, vapers tended to adopt one of two vaper identities, that of the ‘cloud chaser’ or the ‘substitute’, which some users moved between during different stages of their vaping career. The social and symbolic meaning of e-cigarettes and vaping were diverse. ‘Cloud chasers’ connected with the vaper subculture in varying degrees and involved concepts of pleasure, community and performance. However, the aesthetic and performance part of the subculture, in particular, had little appeal to ‘substitute’ vapers who largely viewed their use of e-cigarettes as a means to quit smoking, and enjoyment did not play a substantive role in their use. Understanding the complexities of vaping, and the nuanced differences of ‘cloud chasers’ and ‘substitute’ vapers may have important implications for health communication, research and policy. Our findings add to the understanding of the varying motives for use and provide new insights into the socialisation process and subsequent identity adoption of Western Australian vapers.

Availability of data and materials

The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.

The Therapeutic Goods Administration is the regulatory body for therapeutic goods in Australia and is responsible for conducting assessment and monitoring activities to ensure that therapeutic goods available in Australia are of an acceptable standard and that access to therapeutic advances is in a timely manner.

Abbreviations

Electronic cigarette

Electronic Nicotine Delivery Device

COnsolidated criteria for REporting Qualitative research

Greater Capital City Statistical Area

Index of Relative Socio-Economic Advantage and Disadvantage

National Drug Strategy Household Survey

Therapeutic Goods Administration

United States

United Kingdom

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Acknowledgements

We wish to thank the people who participated in this study and willingly provided their time and insights.

This research was supported by a Healthway Exploratory Research Grant [grant number 32803] and an Australian Government Research Training Program Scholarship. The Scholarship is provided by the Commonwealth of Australia to support the general living costs for students undertaking Doctoral Research studies. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, and in the decision to publish the results.

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Conception and design of the work: JJ, BM, KM, TL, KW; Data acquisition and analysis: KM; Data interpretation: KM, BM; Writing – original draft: KM; Writing - review and editing: JJ, BM, BF, KW, TL. All authors read and approved the final manuscript.

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Participants gave written (at the time of the interview, or via email), and in one case verbal consent before participating in a face-to-face ( n  = 35) or telephone ( n  = 2) interview. All procedures were performed in compliance with relevant laws and institutional guidelines and the study protocol was approved by the Human Research Ethics Committee of Curtin University (HRE2017–0144).

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BF is a member of the NHMRC Electronic Cigarettes Working Committee (May 2020). She has received consulting payment for e-cigarette policy review for the NSW National Heart Foundation (December 2019). She had travel expenses (flight and registration) reimbursed to attend Oceania Tobacco Control Conference 2017 to present on e-cigarette and cessation. She provided her opinion (unpaid) at Australian Parliament’s Standing Committee on Health, Aged Care and Sport public hearing into the Use and Marketing of Electronic Cigarettes and Personal Vaporisers (September 8, 2017). She led a contract on e-cigarette regulation in Australia for the Commonwealth Department of Health (2016). She had travel expenses reimbursed by National Taiwan University for presenting on e-cigarette regulation (2016). The other authors have no conflicts to declare.

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Data collection guide. The data collection guide includes the information recorded about the interview, participant’s demographic and behavioural information and the interview guide.

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COREQ checklist. A checklist of items that should be included in reports of qualitative research.

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McCausland, K., Jancey, J., Leaver, T. et al. Motivations for use, identity and the vaper subculture: a qualitative study of the experiences of Western Australian vapers. BMC Public Health 20 , 1552 (2020). https://doi.org/10.1186/s12889-020-09651-z

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National Center for Chronic Disease Prevention and Health Promotion (US) Office on Smoking and Health. E-Cigarette Use Among Youth and Young Adults: A Report of the Surgeon General [Internet]. Atlanta (GA): Centers for Disease Control and Prevention (US); 2016.

E-Cigarette Use Among Youth and Young Adults: A Report of the Surgeon General [Internet].

Chapter 1 introduction, conclusions, and historical background relative to e-cigarettes.

• Introduction

Although conventional cigarette smoking has declined markedly over the past several decades among youth and young adults in the United States ( U.S. Department of Health and Human Services [USDHHS] 2012 ), there have been substantial increases in the use of emerging tobacco products among these populations in recent years ( Centers for Disease Control and Prevention [CDC] 2015c ). Among these increases has been a dramatic rise in electronic cigarette (e-cigarette) use among youth and young adults. It is crucial that the progress made in reducing cigarette smoking among youth and young adults not be compromised by the initiation and use of e-cigarettes. This Surgeon General’s report focuses on the history, epidemiology, and health effects of e-cigarette use among youth and young adults; the companies involved with marketing and promoting these products; and existing and proposed public health policies regarding the use of these products by youth and young adults.

E-cigarettes include a diverse group of devices that allow users to inhale an aerosol, which typically contains nicotine, flavorings, and other additives. E-cigarettes vary widely in design and appearance, but generally operate in a similar manner and are composed of similar components ( Figure 1.1 ). A key challenge for surveillance of the products and understanding their patterns of use is the diverse and nonstandard nomenclature for the devices ( Alexander et al. 2016 ). These devices are referred to, by the companies themselves, and by consumers, as “e-cigarettes,” “e-cigs,” “cigalikes,” “e-hookahs,” “mods,” “vape pens,” “vapes,” and “tank systems.” In this report, the term “e-cigarette” is used to represent all of the various products in this rapidly diversifying product category. The terms may differ by geographic region or simply by the prevailing preferences among young users. For example, some refer to all cigarette-shaped products as “e-cigarettes” or as “cigalikes,” and some may refer to the pen-style e-cigarettes as “hookah pens” or “vape pens” ( Richtel 2014 ; Lempert et al. 2016 ).

Diversity of e-cigarette products. Source: Photo by Mandie Mills, CDC.

This report focuses on research conducted among youth and young adults because of the implications of e-cigarette use in this population, particularly the potential for future public health problems. Understanding e-cigarette use among young persons is critical because previous research suggests that about 9 in 10 adult smokers first try conventional cigarettes during adolescence ( USDHHS 2012 ). Similarly, youth e-cigarette experimentation and use could also extend into adulthood; however, e-cigarette use in this population has not been examined in previous reports of the Surgeon General. The first Surgeon General’s report on the health consequences of smoking was published in 1964; of the subsequent reports, those published in 1994 and 2012 focused solely on youth and young adults ( USDHHS 1994 , 2012 ). More recently, the 2012 report documented the evidence regarding tobacco use among youth and young adults, concluding that declines in cigarette smoking had slowed and that decreases in the use of smokeless tobacco had stalled. That report also found that the tobacco industry’s advertising and promotional activities are causal to the onset of smoking in youth and young adults and the continuation of such use as adults ( USDHHS 2012 ). However, the 2012 report was prepared before e-cigarettes were as widely promoted and used in the United States as they are now. Therefore, this 2016 report documents the scientific literature on these new products and their marketing, within the context of youth and young adults. This report also looks to the future by examining the potential impact of e-cigarette use among youth and young adults, while also summarizing the research on current use, health consequences, and marketing as it applies to youth and young adults.

Evidence for this report was gathered from studies that included one or more of three age groups. We defined these age groups to be young adolescents (11–13 years of age), adolescents (14–17 years of age), and young adults (18–24 years of age). Some studies refer to the younger groups more generally as youth. Despite important issues related to e-cigarette use in adult populations, clinical and otherwise (e. g ., their potential for use in conventional smoking cessation), that literature will generally not be included in this report unless it also discusses youth and young adults ( Farsalinos and Polosa 2014 ; Franck et al. 2014 ; Grana et al. 2014 ).

Given the recency of the research that pertains to e-cigarettes, compared with the decades of research on cigarette smoking, the “precautionary principle” is used to guide actions to address e-cigarette use among youth and young adults. This principle supports intervention to avoid possible health risks when the potential risks remain uncertain and have been as yet partially undefined ( Bialous and Sarma 2014 ; Saitta et al. 2014 ; Hagopian et al. 2015 ). Still, the report underscores and draws its conclusions from the known health risks of e-cigarette use in this age group.

Organization of the Report

This chapter presents a brief introduction to this report and includes its major conclusions followed by the conclusions of the chapters, the historical background of e-cigarettes, descriptions of the products, a review of the marketing and promotional activities of e-cigarette companies, and the current status of regulations from the U.S. Food and Drug Administration ( FDA ). Chapter 2 (“Patterns of E-Cigarette Use Among U.S. Youth and Young Adults”) describes the epidemiology of e-cigarette use, including current use (i.e., past 30 day); ever use; co-occurrence of using e-cigarettes with other tobacco products, like cigarettes; and psychosocial factors associated with using e-cigarettes, relying on data from the most recent nationally representative studies available at the time this report was prepared. Chapter 3 (“Health Effects of E-Cigarette Use Among U.S. Youth and Young Adults”) documents the evidence related to the health effects of e-cigarette use, including those that are associated with direct aerosol inhalation by users, the indirect health effects of e-cigarette use, other non-aerosol health effects of e-cigarette use, and secondhand exposure to constituents of the aerosol. Chapter 4 (“Activities of the E-Cigarette Companies”) describes e-cigarette companies’ influences on e-cigarette use and considers manufacturing and price; the impact of price on sales and use; the rapid changes in the industry, particularly the e-cigarette companies; and the marketing and promotion of e-cigarettes. Chapter 5 (“E-Cigarette Policy and Practice Implications”) discusses the implications for policy and practice at the national, state, and local levels. The report ends with a Call to Action to stakeholders—including policymakers, public health practitioners and clinicians, researchers, and the public—to work to prevent harms from e-cigarette use and secondhand aerosol exposure among youth and young adults.

Preparation of this Report

This Surgeon General’s report was prepared by the Office on Smoking and Health, National Center for Chronic Disease Prevention and Health Promotion, CDC , which is part of USDHHS . The initial drafts of the chapters were written by 27 experts who were selected for their knowledge of the topics addressed. These contributions are summarized in five chapters that were evaluated by approximately 30 peer reviewers. After peer review, the entire manuscript was sent to more than 20 scientists and other experts, who examined it for its scientific integrity. After each review cycle, the drafts were revised by the report’s scientific editors on the basis of reviewers’ comments. Subsequently, the report was reviewed by various institutes and agencies within USDHHS.

Scientific Basis of the Report

The statements and conclusions throughout this report are documented by the citation of studies published in the scientific literature. Publication lags have prevented an up-to-the-minute inclusion of all recently published articles and data. This overall report primarily cites peer-reviewed journal articles, including reviews that integrate findings from numerous studies and books that were published through December 2015. However, selected studies from 2016 have been added during the review process that provide further support for the conclusions in this report. When a cited study has been accepted for publication, but the publication has not yet occurred because of the delay between acceptance and final publication, the study is referred to as “in press.” This report also refers, on occasion, to unpublished research, such as presentations at a professional meeting, personal communications from a researcher, or information available in various media. These references are employed when acknowledged by the editors and reviewers as being from reliable sources, which add to the emerging literature on a topic.

• Major Conclusions
• E-cigarettes are a rapidly emerging and diversified product class. These devices typically deliver nicotine, flavorings, and other additives to users via an inhaled aerosol. These devices are referred to by a variety of names, including “e-cigs,” “e-hookahs,” “mods,” “vape pens,” “vapes,” and “tank systems.”
• E-cigarette use among youth and young adults has become a public health concern. In 2014, current use of e-cigarettes by young adults 18–24 years of age surpassed that of adults 25 years of age and older.
• E-cigarettes are now the most commonly used tobacco product among youth, surpassing conventional cigarettes in 2014. E-cigarette use is strongly associated with the use of other tobacco products among youth and young adults, including combustible tobacco products.
• The use of products containing nicotine poses dangers to youth, pregnant women, and fetuses. The use of products containing nicotine in any form among youth, including in e-cigarettes, is unsafe.
• E-cigarette aerosol is not harmless. It can contain harmful and potentially harmful constituents, including nicotine. Nicotine exposure during adolescence can cause addiction and can harm the developing adolescent brain.
• E-cigarettes are marketed by promoting flavors and using a wide variety of media channels and approaches that have been used in the past for marketing conventional tobacco products to youth and young adults.
• Action can be taken at the national, state, local, tribal, and territorial levels to address e-cigarette use among youth and young adults. Actions could include incorporating e-cigarettes into smokefree policies, preventing access to e-cigarettes by youth, price and tax policies, retail licensure, regulation of e-cigarette marketing likely to attract youth, and educational initiatives targeting youth and young adults.
• Chapter Conclusions

Chapter 1. Introduction, Conclusions, and Historical Background Relative to E-Cigarettes

• E-cigarettes are devices that typically deliver nicotine, flavorings, and other additives to users via an inhaled aerosol. These devices are referred to by a variety of names, including “e-cigs,” “e-hookahs,” “mods,” “vape pens,” “vapes,” and “tank systems.”
• E-cigarettes represent an evolution in a long history of tobacco products in the United States, including conventional cigarettes.
• In May 2016, the Food and Drug Administration issued the deeming rule, exercising its regulatory authority over e-cigarettes as a tobacco product.

Chapter 2. Patterns of E-Cigarette Use Among U.S. Youth and Young Adults

• Among middle and high school students, both ever and past-30-day e-cigarette use have more than tripled since 2011. Among young adults 18–24 years of age, ever e-cigarette use more than doubled from 2013 to 2014 following a period of relative stability from 2011 to 2013.
• The most recent data available show that the prevalence of past-30-day use of e-cigarettes is similar among high school students (16% in 2015, 13.4% in 2014) and young adults 18–24 years of age (13.6% in 2013–2014) compared to middle school students (5.3% in 2015, 3.9% in 2014) and adults 25 years of age and older (5.7% in 2013–2014).
• Exclusive, past-30-day use of e-cigarettes among 8th-, 10th-, and 12th-grade students (6.8%, 10.4%, and 10.4%, respectively) exceeded exclusive, past-30-day use of conventional cigarettes in 2015 (1.4%, 2.2%, and 5.3%, respectively). In contrast—in 2013–2014 among young adults 18–24 years of age—exclusive, past-30-day use of conventional cigarettes (9.6%) exceeded exclusive, past-30-day use of e-cigarettes (6.1%). For both age groups, dual use of these products is common.
• E-cigarette use is strongly associated with the use of other tobacco products among youth and young adults, particularly the use of combustible tobacco products. For example, in 2015, 58.8% of high school students who were current users of combustible tobacco products were also current users of e-cigarettes.
• Among youth—older students, Hispanics, and Whites are more likely to use e-cigarettes than younger students and Blacks. Among young adults—males, Hispanics, Whites, and those with lower levels of education are more likely to use e-cigarettes than females, Blacks, and those with higher levels of education.
• The most commonly cited reasons for using e-cigarettes among both youth and young adults are curiosity, flavoring/taste, and low perceived harm compared to other tobacco products. The use of e-cigarettes as an aid to quit conventional cigarettes is not reported as a primary reason for use among youth and young adults.
• Flavored e-cigarette use among young adult current users (18–24 years of age) exceeds that of older adult current users (25 years of age and older). Moreover, among youth who have ever tried an e-cigarette, a majority used a flavored product the first time they tried an e-cigarette.
• E-cigarette products can be used as a delivery system for cannabinoids and potentially for other illicit drugs. More specific surveillance measures are needed to assess the use of drugs other than nicotine in e-cigarettes.

Chapter 3. Health Effects of E-Cigarette Use Among U.S. Youth and Young Adults

• Nicotine exposure during adolescence can cause addiction and can harm the developing adolescent brain.
• Nicotine can cross the placenta and has known effects on fetal and postnatal development. Therefore, nicotine delivered by e-cigarettes during pregnancy can result in multiple adverse consequences, including sudden infant death syndrome, and could result in altered corpus callosum, deficits in auditory processing, and obesity.
• E-cigarettes can expose users to several chemicals, including nicotine, carbonyl compounds, and volatile organic compounds, known to have adverse health effects. The health effects and potentially harmful doses of heated and aerosolized constituents of e-cigarette liquids, including solvents, flavorants, and toxicants, are not completely understood.
• E-cigarette aerosol is not harmless “water vapor,” although it generally contains fewer toxicants than combustible tobacco products.
• Ingestion of e-cigarette liquids containing nicotine can cause acute toxicity and possibly death if the contents of refill cartridges or bottles containing nicotine are consumed.

Chapter 4. Activities of the E-Cigarette Companies

• The e-cigarette market has grown and changed rapidly, with notable increases in total sales of e-cigarette products, types of products, consolidation of companies, marketing expenses, and sales channels.
• Prices of e-cigarette products are inversely related to sales volume: as prices have declined, sales have sharply increased.
• E-cigarette products are marketed in a wide variety of channels that have broad reach among youth and young adults, including television, point-of-sale, magazines, promotional activities, radio, and the Internet.
• Themes in e-cigarette marketing, including sexual content and customer satisfaction, are parallel to themes and techniques that have been found to be appealing to youth and young adults in conventional cigarette advertising and promotion.

Chapter 5. E-Cigarette Policy and Practice Implications

• The dynamic nature of the e-cigarette landscape calls for expansion and enhancement of tobacco-related surveillance to include (a) tracking patterns of use in priority populations; (b) monitoring the characteristics of the retail market; (c) examining policies at the national, state, local, tribal, and territorial levels; (d) examining the channels and messaging for marketing e-cigarettes in order to more fully understand the impact future regulations could have; and (e) searching for sentinel health events in youth and young adult e-cigarette users, while longer-term health consequences are tracked.
• Strategic, comprehensive research is critical to identify and characterize the potential health risks from e-cigarette use, particularly among youth and young adults.
• The adoption of public health strategies that are precautionary to protect youth and young adults from adverse effects related to e-cigarettes is justified.
• A broad program of behavioral, communications, and educational research is crucial to assess how youth perceive e-cigarettes and associated marketing messages, and to determine what kinds of tobacco control communication strategies and channels are most effective.
• Health professionals represent an important channel for education about e-cigarettes, particularly for youth and young adults.
• Diverse actions, modeled after evidence-based tobacco control strategies, can be taken at the state, local, tribal, and territorial levels to address e-cigarette use among youth and young adults, including incorporating e-cigarettes into smoke-free policies; preventing the access of youth to e-cigarettes; price and tax policies; retail licensure; regulation of e-cigarette marketing that is likely to attract youth and young adults, to the extent feasible under the law; and educational initiatives targeting youth and young adults. Among others, research focused on policy, economics, and the e-cigarette industry will aid in the development and implementation of evidence-based strategies and best practices.
• Historical Background

Understanding the role of e-cigarettes requires understanding the long history of tobacco use in the United States, including the role of nicotine delivery, the multiple examples of “reduced-harm” products and associated health claims, and the impact of using tobacco products on the public’s health. Since the late nineteenth century, when the “modern” cigarette came into use, scientists and public health officials have linked cigarette smoking to a remarkable number of adverse effects, and it is now recognized as the primary cause of premature death in the United States ( USDHHS 2014 ). Correspondingly, for a century, manufacturers, scientists, entrepreneurs, and public health leaders have promoted or recommended product changes that might remove some of the harmful elements in cigarette smoke. E-cigarettes are among the latest products.

E-cigarettes are designed for users to inhale nicotine, flavorings, and other additives through an aerosol. The claims and marketing strategies employed by the e-cigarette companies, and the efforts made by others to develop scientific and regulatory tools to deal with these new products, both contribute to the current discourse on e-cigarettes. Many lessons for assessing the potential (and future) consequences of these products can be learned from examining the relevant experiences of the past century, especially the introduction of novel products (including e-cigarettes as well as other tobacco and nicotine products) and the claims of reduced exposure to toxins made by the industry and elsewhere.

Early Efforts to Modify Cigarettes

In the 1880s and 1890s, entrepreneurs promoted novel products that allegedly blocked nicotine and other constituents of conventional cigarettes believed to be poisonous. Dr. Scott’s Electric Cigarettes, advertised in Harper’s Weekly, claimed not only to light without matches but also to contain a cotton filter that “strains and eliminates the injurious qualities from the smoke,” including nicotine ( Harper’s Weekly 1887 ). Nicotine delivery was essential to the development of the modern cigarette in the twentieth century; early on, this substance was thought to be addicting and thus vital to retaining customers. In 1913, the Camel brand was a new kind of cigarette that introduced high-nicotine content by using burley tobacco, which was generally too harsh to inhale into the lungs, but was made more inhalable through the addition of casings (e. g ., sugars, licorice) ( Tindall 1992 ; Proctor 2011 ). In 1916, American Tobacco introduced its Lucky Strike blended cigarette, and in 1918 Liggett & Myers ( L &M) reformulated its Chesterfield brand to make it more palatable to users. As the market grew, advertisements for major brands routinely included health-related statements and testimonials from physicians. During the 1930s and 1940s, prominent advertising campaigns included claims like “Not a cough in a carload” (Old Gold) ( Federal Trade Commission [FTC] 1964 , p. LBA-5); “We removed from the tobacco harmful corrosive ACRIDS (pungent irritants) present in cigarettes manufactured in the old-fashioned way” (Lucky Strike) ( FTC 1964 , p. LBA-2); and “Smoking Camels stimulates the natural flow of digestive fluids … increases alkalinity” (Camel) ( FTC 1964 , p. LBA-1a). Thus, early modifications to the cigarette were made so that it was more palatable, had a higher nicotine delivery and uptake, and could be marketed as “safe” ( FTC 1964 ; Calfee 1985 ).

Filters, Tar Reduction, and Light and Low-Tar Cigarettes

The landmark 1964 Surgeon General’s report on smoking and health concluded that cigarette smoking contributed substantially to mortality from certain specific diseases, including lung cancer ( U.S. Department of Health, Education, and Welfare 1964 ). Although the 1964 report considered the topic, it found the evidence insufficient to assess the potential health benefits of cigarette filters. Cigarettes with filters became the norm by the 1960s, and marketing them with an overt message about harm reduction became the standard ( National Cancer Institute [NCI] 1996 ). However, the Surgeon General convened another group of experts on June 1, 1966, to review the evidence on the role played by the tar and nicotine content in health. The group concluded that “[t]he preponderance of scientific evidence strongly suggests that the lower the ‘tar’ and nicotine content of cigarette smoke, the less harmful are the effects” ( Horn 1966 , p. 16,168). Subsequent studies have repeatedly failed to demonstrate health benefits of smoking light and low-tar cigarettes versus full-flavor cigarettes ( Herning et al. 1981 ; Russell et al. 1982 ; Benowitz et al. 1983 , NCI 2001 ).

Over the years, the tobacco industry used multiple methods to reduce the machine-tested yields of tar and nicotine in cigarettes as a way to claim “healthier” cigarettes. Beginning in the 1970s, tobacco companies advertised the tar and nicotine levels for their cigarettes, which encouraged smokers to believe, without substantiation, they could reduce their risk of exposure to these constituents ( Cummings et al. 2002 ; Pollay and Dewhirst 2002 ). In 1996, the FTC issued a statement that it would allow cigarette companies to include statements about tar and nicotine content in their advertising as long as they used a standardized machine-testing method ( Peeler 1996 ).

The Role of Nicotine and Nicotine Delivery

Although the public health community understood early on that nicotine was the primary psycho-active ingredient in cigarette smoke, before the 1980s, little was known about the importance of nicotine in the addiction process beyond what the cigarette manufacturers had learned from their own research. Some scientists warned that due to nicotine addiction, a reduction in nicotine yields, along with decreases in tar, could lead smokers to change their smoking behavior, such as by smoking a greater number of cigarettes to maintain their nicotine intake or changing their behavior in more subtle ways, such as varying the depth of inhalation or smoking more of the cigarette ( Jarvis et al. 2001 ; National Cancer Institute 2001 ; Thun and Burns 2001 ). Not until the 1970s and 1980s, as researchers studying other forms of drug abuse began to apply their research methods to cigarette smoking, did it become apparent that nicotine was similar in its addictive capability to other drugs of abuse, such as heroin and cocaine ( USDHHS 1981 , 1988 ). As described in the 1988 Surgeon General’s report and in subsequent research, symptoms associated with nicotine addiction include craving, withdrawal, and unconscious behaviors to ensure consistent intake of nicotine ( USDHHS 1988 ; al’Absi et al. 2002 ; Hughes 2007 ).

Although the tobacco industry has long understood the importance of nicotine to maintain long-term cigarette smokers through addiction, public health officials did not fully appreciate this in a broad sense until the 1988 Surgeon General’s report, The Health Consequences of Smoking: Nicotine Addiction ( USDHHS 1988 ).

FDA and Nicotine Regulation

In 1988 (and again in 1994), the Coalition on Smoking OR Health and other public-interest organizations petitioned FDA to classify low-tar and nicotine products as drugs and to classify Premier, the short-lived “smokeless cigarette product” from R.J. Reynolds, as an alternative nicotine-delivery system ( Stratton et al. 2001 ). The Coalition on Smoking OR Health cited indirect claims made through advertising and marketing as evidence of R. J. Reynolds’s intent to have the product used for the mitigation or prevention of disease ( Slade and Ballin 1993 ). Meanwhile, FDA launched an investigation into the practices of the tobacco industry, including the manipulation of nicotine delivery. FDA asserted its jurisdiction over cigarettes and smokeless tobacco and issued certain rules governing access to and promotion of these products ( Federal Register 1996 ). On March 21, 2000, the U.S. Supreme Court ruled 5-4 that Congress had not yet given FDA the necessary statutory authority to issue any rules pertaining to tobacco products ( Gottleib 2000 ; FDA v. Brown & Williamson Tobacco Corp. 2000 ). The subsequent debate over control of nicotine products, including their potential impact on youth, ultimately led to the passage of the 2009 Family Smoking Prevention and Tobacco Control Act, which gave FDA authority to regulate tobacco products. Thus, discussions about the introduction of novel nicotine-containing tobacco products in the market during the 1980s and 1990s helped shape the current regulation of tobacco and nicotine products.

New products introduced in the 1990s or later included modified tobacco cigarettes (e. g ., Advance, Omni); cigarette-like products, also called cigalikes (e.g., Eclipse, Accord); and smokeless tobacco products (e.g., Ariva, Exalt, Revel, snus). Advance, made by Brown and Williamson, was test-marketed with the slogan “All of the taste … Less of the toxins.” Vector launched a national advertising campaign for its Omni cigarette with the slogan “Reduced carcinogens. Premium taste.” In addition to the question of whether the claims were supported by sufficient evidence, scientists and tobacco control leaders raised concerns about the potential for adverse consequences associated with novel nicotine and tobacco products marketed for harm reduction, such as a reduction in cessation rates or increased experimentation by children ( Warner and Martin 2003 ; Joseph et al. 2004 ; Caraballo et al. 2006 ). Studies have shown that smokers are interested in trying novel “reduced-exposure” products and perceive them to have lower health risks, even when advertising messages do not make explicit health claims ( Hamilton et al. 2004 ; O’Connor et al. 2005 ; Caraballo et al. 2006 ; Choi et al. 2012 ; Pearson et al. 2012 ).

At FDA ’s request, the Institute of Medicine ( IOM [now the National Academy of Medicine]) convened a committee of experts to formulate scientific methods and standards by which potentially reduced-exposure products (PREPs), whether the purported reduction was pharmaceutical or tobacco related, could be assessed. The committee concluded that “[f]or many diseases attributable to tobacco use, reducing risk of disease by reducing exposure to tobacco toxicants is feasible” ( Stratton et al. 2001 , p. 232). However, it also cautioned that “PREPs have not yet been evaluated comprehensively enough (including for a sufficient time) to provide a scientific basis for concluding that they are associated with a reduced risk of dis ease compared to conventional tobacco use” ( Stratton et al. 2001 , p. 232). The committee added that “the major concern for public health is that tobacco users who might otherwise quit will use PREPs instead, or others may initiate smoking, feeling that PREPs are safe. That will lead to less harm reduction for a population (as well as less risk reduction for that individual) than would occur without the PREP , and possibly to an adverse effect on the population” ( Stratton et al. 2001 , p. 235). Subsequently, in 2006, Judge Kessler cited these findings in her decision which demanded the removal of light and low-tar labeling due to the misleading nature of these claims ( United States v. Philip Morris 2006 ).

• The E-Cigarette

Invention of the E-Cigarette

An early approximation of the current e-cigarette appeared in a U.S. patent application submitted in 1963 by Herbert A. Gilbert and was patented in August 1965 (U.S. Patent No. 3,200,819) ( Gilbert 1965 ). The application was for a “smokeless nontobacco cigarette,” with the aim of providing “a safe and harmless means for and method of smoking” by replacing burning tobacco and paper with heated, moist, flavored air. A battery-powered heating element would heat the flavor elements without combustion ( Gilbert 1965 ). The Favor cigarette, introduced in 1986, was another early noncombustible product promoted as an alternative nicotine-containing tobacco product ( United Press International 1986 ; Ling and Glantz 2005 ).

The first device in the recent innovation in e-cigarettes was developed in 2003 by the Chinese pharmacist Hon Lik, a former deputy director of the Institute of Chinese Medicine in Liaoning Province. Lik’s patent application described a kind of electronic atomizing cigarette ( Hon 2013 ). With support from Chinese investors, in 2004 the product was introduced on the Chinese market under the company name Ruyan ( Sanford and Goebel 2014 ). The product gained some attention among Chinese smokers early on as a potential cessation device or an alternative cigarette product.

The e-cigarette was part of the U.S. market by the mid-2000s, and by 2010 additional brands started to appear in the nation’s marketplace, including Ruyan and Janty ( Regan et al. 2013 ). Ruyan gained a U.S. patent for its product with the application stating that the product is “an electronic atomization cigarette that functions as substitutes (sic) for quitting smoking and cigarette substitutes.” (U.S. Patent No. 8,490,628 B2, 2013). In August 2013, Imperial Tobacco Group purchased the intellectual property behind the Ruyan e-cigarette for $75 million. As of 2014 an estimated 90% of the world’s production of e-cigarette technology and products came from mainland China, mainly Guangdong Province and Zhejiang Province ( Barboza 2014 ).

Sales of e-cigarettes in the United States have risen rapidly since 2007. Widespread advertising via television commercials and through print advertisements for popular brands, often featuring celebrities, has contributed to a large increase in e-cigarette use by both adults and youth since 2010 ( Felberbaum 2013 ; King et al. 2013 ; Regan et al. 2013 ). Additionally, marketing through social media, as well as other forms of Internet marketing, has been employed to market these devices ( Huang et al. 2014 ; Kim et al. 2014 ).

In 2013, an estimated 13.1 million middle school and high school students were aware of e-cigarettes ( Wang et al. 2014 ). According to data from the National Youth Tobacco Survey, in 2011 the prevalence of current e-cigarette use (defined as use during at least 1 day in the past 30 days) among high school students was 1.5%; prevalence increased dramatically, however, to 16% by 2015, surpassing the rate of conventional-cigarette use among high school students ( CDC 2016b ; see Chapter 2 ). This equates to 2.4 million high school students and 620,000 middle school students having used an e-cigarette at least one time in the past 30 days in 2015 ( CDC 2016b ).

These trends have led to substantial concern and discussion within public health communities, including state and national public health agencies, professional organizations, and school administrators and teachers. A primary concern is the potential for nicotine addiction among nonsmokers, especially youth and young adults, and that this exposure to nicotine among youth and young adults is harmful. The diversity and novelty of e-cigarette products on the market and ongoing product innovations make assessments of the biological effects of current e-cigarettes under actual conditions of use—such as their long-term harmfulness—difficult to measure. Unanswered questions remain about the risk profile of these devices, their potential use by young people as a first step to other nicotine products, and their total impact on public health. There are diverging opinions about the potential public health impact of these new products. Some public health scientists have highlighted the potential for alternative nicotine products to serve as a substitute for conventional cigarettes and thus a harm reduction tool ( Henningfield et al. 2003 ; Abrams 2014 ). Others have cautioned that the use of alternative nicotine products might become a bridge that may lead to greater tobacco product use—including dual- or multiple-product use—or initiate nicotine addiction among nonsmokers, especially youth ( Cobb et al. 2010 ; Wagener et al. 2012 ; Benowitz and Goniewicz 2013 ; Britton 2013 ; Chapman 2013 ; Etter 2013 ; USDHHS 2014 ). Current evidence is insufficient to reject either of these hypotheses.

E-Cigarette Products

Components and devices.

E-cigarette devices are composed of a battery, a reservoir for holding a solution that typically contains nicotine, a heating element or an atomizer, and a mouthpiece through which the user puffs ( Figure 1.2 ). The device heats a liquid solution (often called e-liquid or e-juice) into an aerosol that is inhaled by the user. E-liquid typically uses propylene glycol and/or glycerin as a solvent for the nicotine and flavoring chemicals

Parts of an e-cigarette device. Source: Photo by Mandie Mills, CDC.

Flavors and E-Cigarettes

The e-liquids in e-cigarettes are most often flavored; a study estimated that 7,700 unique flavors exist ( Zhu et al. 2014 ) and that most of them are fruit or candy flavors ( Figure 1.3 ). A content analysis of the products available via online retail websites documented that tobacco, mint, coffee, and fruit flavors were most common, followed by candy (e. g ., bubble gum), unique flavors (e.g., Belgian waffle), and alcoholic drink flavors (e.g., strawberry daiquiri) ( Grana and Ling 2014 ). Some retail stores are also manufacturers that create custom flavors, which increases the variety of flavors available.

Examples of e-liquid flavors. Source: Photo by Mandie Mills, CDC.

The widespread availability and popularity of flavored e-cigarettes is a key concern regarding the potential public health implications of the products. The concern, among youth, is that the availability of e-cigarettes with sweet flavors will facilitate nicotine addiction and simulated smoking behavior—which will lead to the use of conventional tobacco products ( Kong et al. 2015 ; Krishnan-Sarin et al. 2015 ). Flavors have been used for decades to attract youth to tobacco products and to mask the flavor and harshness of tobacco ( USDHHS 2012 ). Industry documents show that tobacco companies marketed flavored little cigars and cigarillos to youth and to African Americans to facilitate their uptake of cigarettes ( Kostygina et al. 2014 ). Companies also intended flavored smokeless tobacco products to facilitate “graduation” to unflavored products that more easily deliver more nicotine to the user ( USDHHS 2012 ). Various studies have shown that youth are more likely than adults to choose flavored cigarettes and cigars ( CDC 2015b ). Concern over these findings led Congress to include a ban on characterizing flavors for cigarettes, other than tobacco or menthol, in the Tobacco Control Act. A similar concern exists about e-cigarettes, and this concern is supported by studies indicating that youth and young adults who have ever used e-cigarettes begin their use with sweet flavors rather than tobacco flavors ( Kong et al. 2015 ; Krishnan-Sarin et al. 2015 ). Notably, 81.5% of current youth e-cigarette users said they used e-cigarettes “because they come in flavors I like” ( Ambrose et al. 2015 ).

E-Cigarette Devices

First-generation e-cigarettes were often similar in size and shape to conventional cigarettes, with a design that also simulated a traditional cigarette in terms of the colors used (e. g ., a white body with tan mouthpiece). These devices were often called cigalikes, but there were other products designed to simulate a cigar or pipe. Other cigalikes were slightly longer or narrower than a cigarette; they may combine white with tan or may be black or colored brightly. These newer models use a cartridge design for the part of the device that holds the e-liquid, which is either prefilled with the liquid or empty and ready to be filled. The user then squeezes drops of the e-liquid onto a wick (or bit of cotton or polyfil) connected to the heating element and atomizer ( Figure 1.4 ). As e-cigarettes have become more popular, their designs have become more diverse, as have the types of venues where they are sold ( Noel et al. 2011 ; Zhu et al. 2014 ).

E-liquids being poured into an e-cigarette device. Source: Photo by Mandie Mills, CDC.

Second-generation devices include products that are shaped like pens, are comparatively larger and cylindrical, and are often referred to as “tank systems” in a nod to the transparent reservoir that holds larger amounts of e-liquid than previous cartridge-containing models. Third- and fourth-generation devices represent a diverse set of products and, aesthetically, constitute the greatest departure from the traditional cigarette shape, as many are square or rectangular and feature customizable and rebuildable atomizers and batteries. In addition, since the beginning of the availability of e-cigarettes and their component parts, users have been modifying the devices or building their own devices, which are often referred to as “mods.” The differences in design and engineering of the products are key factors in the size, distribution, and amount of aerosol particles and the variability in levels of chemicals and nicotine present in the e-liquid/aerosol and delivered to the user ( Brown and Cheng 2014 ).

E-Cigarette Product Components and Risks

One of the primary features of the more recent generation of devices is that they contain larger batteries and are capable of heating the liquid to a higher temperature, potentially releasing more nicotine, forming additional toxicants, and creating larger clouds of particulate matter ( Bhatnagar et al. 2014 ; Kosmider et al. 2014 ). For instance, one study demonstrated that, at high temperatures (150°C), exceedingly high levels of formaldehyde—a carcinogen (found to be 10 times higher than at ambient temperatures)—are present that are formed through the heating of the e-liquid solvents (propylene glycol and glycerin), although the level of tolerance of actual users to the taste of the aerosol heated to this temperature is debated ( Kosmider et al. 2014 ; CDC 2015a ; Flavor and Extract Manufacturers Association of the United States 2015 ; Pankow et al. 2015 ). There is also concern regarding the safety of inhaling e-cigarette flavorings. Although some manufacturers have claimed their flavorants are generally recognized as safe for food additives (i.e., to be used in preparing foods for eating), little is known about the long-term health effects of inhaling these substances into the lungs ( CDC 2015a ).

Many devices can be readily customized by their users, which is also leading to the concern that these devices are often being used to deliver drugs other than nicotine ( Brown and Cheng 2014 ). Most commonly reported in the news media, on blogs, and by user anecdote is the use of certain types of e-cigarette-related products for delivering different forms of marijuana ( Morean et al. 2015 ; Schauer et al. 2016 ). The tank systems, for example, have been used with liquid tetrahydrocannabinol ( THC ) or hash oil. Some personal vaporizer devices can be used with marijuana plant material or a concentrated resin form of marijuana called “wax.” One study describes the use, in Europe, of e-cigarette devices to smoke marijuana ( Etter 2015 ).

The various e-cigarette products, viewed as a group, lack standardization in terms of design, capacity for safely holding e-liquid, packaging of the e-liquid, and features designed to minimize hazards with use ( Yang et al. 2014 ). All of these design features may have implications for the health impact of e-cigarette use. Notably, from 2010 to 2014, calls to poison control centers in the United States about exposures related to e-cigarettes increased dramatically. According to the American Association of Poison Control Centers (2015) , 271 cases were reported in 2011, but 3,783 calls were reported in 2014. Among all calls, 51% involved exposure among children younger than 5 years of age ( CDC 2014 ). Most poisonings appear to have been caused by exposure to nicotine-containing liquid ( CDC 2014 ). The lack of a requirement for child-resistant packaging for e-liquid containers may have contributed to these poisonings. Since these data were released, one death in the United States has been confirmed in a child who drank e-liquid containing nicotine ( Mohney 2014 ). Additionally, serious adverse reactions, including at least two deaths, have been reported to FDA in cases that could be attributed to the use of e-cigarettes ( FDA 2013 ). This increase in poisonings prompted the Child Nicotine Poisoning Prevention Act of 2015 (2016) , which was enacted in January 2016. This law requires any container of liquid nicotine that is sold, manufactured, distributed, or imported into the United States to be placed in packaging that is difficult to open by children under 5 years of age.

Secondary risks are also of concern regarding e-cigarettes, including passive exposure to nicotine and other chemicals, and adverse events due to device malfunction. Nicotine is a neuroteratogen, and its use by pregnant women exposes a developing fetus to risks that are well documented in the 50th-anniversary Surgeon General’s report on smoking ( USDHHS 2014 ) and include impaired brain development ( England et al. 2015 ) and other serious consequences. Finally, another consequence of the lack of device regulation is the occurrence of battery failures and subsequent explosions. Explosions have typically occurred during charging, resulting in house and car fires, and sometimes causing injuries to those involved. From 2009 to late 2014, 25 incidents of explosions and fires involving e-cigarettes occurred in the United States ( Chen 2013 ; U.S. Fire Administration 2014 ; FDA 2013 ).

• E-Cigarette Companies

E-cigarette companies include manufacturers, wholesalers, importers, retailers, distributors, and some other groups that overlap with these entities ( Barboza 2014 ; Whelan 2015 ). Currently, most of the products are manufactured in Shenzhen, Guangdong Province, China ( Cobb et al. 2010 ; Grana et al. 2014 ; Zhu et al. 2014 ). One study placed the number of brands at 466 in January 2014 and found a net increase of 10.5 brands per month ( Zhu et al. 2014 ). All the major tobacco companies (e. g ., Reynolds American, Altria; Table 1.1 ) and many smaller, independent companies are now in the business. When e-cigarettes first entered the U.S. market, they were sold primarily by independent companies via the Internet and in shopping malls at kiosks where those interested could sample the products. A unique feature of the e-cigarette industry, compared to other tobacco and nicotine products, is the recruitment of visitors to their websites as “affiliates” or distributors to help market the products and, in turn, receive commissions on sales ( Grana and Ling 2014 ; Cobb et al. 2015 ). For example, some companies offer a way for users to earn a commission by advertising the products (e.g., a banner ad is placed on one’s website, and when someone clicks on the link and subsequently purchases a product, the website owner gets a percentage commission). Some companies also offer rewards programs for recruiting new customers or for brand loyalty, with web-site users earning points for free or reduced-price products ( Richardson et al. 2015 ).

Multinational tobacco companies with e-cigarette brands.

E-cigarettes are now in widespread national distribution through convenience stores, tobacco stores, pharmacies, “big box” retail chains such as Costco, online retailers, and shops devoted to e-cigarette products (often called “vape shops”) ( Giovenco et al. 2015 ; Public Health Law Center 2015 ). The “vape shops” offer a place to buy customizable devices and e-liquid solutions in many flavors and sometimes include a café or other elements that promote socializing, essentially making such places like a lounge. With the rapid increase in distribution and marketing in the industry, sales have increased rapidly and were projected to reach $2.5 billion in 2014 and $3.5 billion in 2015, including projections for retail and online channels, as well as “vape shops” ( Wells Fargo Securities 2015 ).

The advertising and marketing of e-cigarette products has engendered skepticism among public health professionals and legislators, who have noted many similarities to the advertising claims and promotional tactics used for decades by the tobacco industry to sell conventional tobacco products ( Campaign for Tobacco-Free Kids 2013 ; CDC 2016a ). Indeed, several of the e-cigarette marketing themes have been reprised from the most memorable cigarette advertising, including those focused on freedom, rebellion, and glamor ( Grana and Ling 2014 ). E-cigarette products are marketed with a variety of unsubstantiated health and cessation messages, with some websites featuring videos of endorsements by physicians (another reprisal of old tobacco industry advertising) ( Grana and Ling 2014 ; Zhu et al. 2014 ). Unlike conventional cigarettes, for which advertising has been prohibited from radio and television since 1971, e-cigarette products are advertised on both radio and television, with many ads featuring celebrities. E-cigarettes also are promoted through sports and music festival sponsorships, in contrast to conventional cigarettes and smokeless tobacco products, which have been prohibited from such sponsorships since the Master Settlement Agreement in 1998. E-cigarettes also appear as product placements in television shows and movies ( Grana et al. 2011 ; Grana and Ling 2014 ).

Another key avenue for e-cigarette promotion is social media, such as Twitter, Facebook, YouTube, and Instagram. As is true in the tobacco industry, the e-cigarette industry organizes users through advocacy groups ( Noel et al. 2011 ; Harris et al. 2014 ; Saitta et al. 2014 ; Caponnetto et al. 2015 ). The extensive marketing and advocacy through various channels broadens exposure to e-cigarette marketing messages and products; such activity may encourage nonsmokers, particularly youth and young adults, to perceive e-cigarette use as socially normative. The plethora of unregulated advertising is of particular concern, as exposure to advertising for tobacco products among youth is associated with cigarette smoking in a dose-response fashion ( USDHHS 2012 ).

• Federal Regulation of E-Cigarettes

A “Two-Pronged” Approach to Comprehensive Tobacco Control

Since the passage of the Tobacco Control Act in 2009, FDA has had the authority to regulate the manufacturing, distribution, and marketing of tobacco products sold in the United States. FDA had immediate jurisdiction over cigarettes, roll-your-own cigarette tobacco, and smokeless tobacco. In May 2016, FDA asserted jurisdiction over products that meet the statutory definition of a tobacco product, including e-cigarettes, except accessories of these products ( Federal Register 2016 ). That regulation is currently under litigation.

The IOM ’s 2007 report, Ending the Tobacco Problem: A Blueprint for the Nation, established a “two-pronged” strategy for comprehensive tobacco control: (1) full implementation of proven, traditional tobacco control measures such as clean indoor air laws, taxation, and countermarketing campaigns; and (2) “strong federal regulation of tobacco products and their marketing and distribution” ( Bonnie et al. 2007 , p. 1).

Included in FDA ’s broad authority are the restriction of marketing and sales to youth, requiring disclosure of ingredients and harmful and potentially harmful constituents, setting product standards (e. g ., requiring the reduction or elimination of ingredients or constituents), requiring premarket approval of new tobacco products and review of modified-risk tobacco products, and requiring health warnings. The standard for FDA to use many of its regulatory authorities is whether such an action is appropriate for the protection of public health ( Federal Food, Drug, and Cosmetic Act , § 907(a)(3)(A)). The public health standard in the Tobacco Control Act also requires FDA to consider the health impact of certain regulatory actions at both the individual and population levels, including their impact on nonusers, and on initiation and cessation ( Federal Food, Drug, and Cosmetic Act , § 907(a)(3)(B)).

Importantly, the Tobacco Control Act preserves the authority of state, local, tribal, and territorial governments to enact any policy “in addition to, or more stringent than” requirements established under the Tobacco Control Act “relating to or prohibiting the sale, distribution, possession, exposure to, access to, advertising and promotion of, or use of tobacco products by individuals of any age” ( Federal Food, Drug, and Cosmetic Act , § 916(a)(1)). This preservation of state and local authority ensures the continuation of more local-level, comprehensive tobacco control. However, the statute expressly preempts states and localities from establishing or continuing requirements that are different from or in addition to FDA requirements regarding standards for tobacco products, premarket review, adulteration, misbranding, labeling, registration, good manufacturing practices, or modified-risk tobacco products ( Federal Food, Drug, and Cosmetic Act , § 916(a)(2)(A)). But this express preemption provision does not apply to state and local authority to impose requirements relating to the “sale, distribution, possession, information reporting to the State, exposure to, access to, the advertising and promotion of, or use of, tobacco products by individuals of any age …” ( Federal Food, Drug, and Cosmetic Act , § 916(a)(2)(b)). The interaction of these complex provisions related to federal preemption of state law has been the subject of challenges by the tobacco industry to state and local laws. Thus far, courts have upheld certain local ordinances restricting the sale of flavored tobacco products ( National Association of Tobacco Outlets, Inc. v. City of Providence 2013 ; U.S. Smokeless Tobacco Manufacturing Co. v. City of New York 2013 ).

Legal Basis for Regulating E-Cigarettes as Tobacco Products

In the United States, e-cigarettes can be regulated either as products marketed for therapeutic purposes or as tobacco products. Since the advent of e-cigarettes in the United States around 2007, manufacturers have had the option to apply to FDA ’s Center for Drug Evaluation and Research ( CDER ) or Center for Devices and Radiological Health (CDRH) for approval to market e-cigarettes for therapeutic purposes; as of August 2016, no e-cigarette manufacturers have received approval through this avenue.

In 2008 and early 2009, FDA detained multiple shipments of e-cigarettes from overseas manufacturers and denied them entry into the United States on the grounds that e-cigarettes were unapproved drug-device combination products ( FDA 2011 ). Sottera, Inc., which now does business as NJOY, challenged that determination ( Smoking Everywhere, Inc. and Sottera, Inc., d/b/a NJOY v. U.S. Food and Drug Administration, et al. 2010 ; Bloomberg Business 2015 ). Between the filing of the lawsuit and a decision on the motion for preliminary injunction, Congress passed the Tobacco Control Act and the President signed it into law. The Tobacco Control Act defines the term “tobacco product,” in part, as any product, including component parts or accessories, “made or derived from tobacco” that is not a “drug,” “device,” or “combination product” as defined by the Federal Food, Drug, and Cosmetic Act (21 U.S.C. 321(rr)) ( Family Smoking Prevention and Tobacco Control Act 2009 , § 101(a)). The District Court subsequently granted a preliminary injunction relying on the Supreme Court’s decision in Brown and Williamson (1996) and the recently enacted Tobacco Control Act. FDA appealed the decision and the U.S. Court of Appeals for the D.C. Circuit held that e-cigarettes and, therefore, other products “made or derived from tobacco” are not drug/device combinations unless they are marketed for therapeutic purposes, but can be regulated by FDA as tobacco products under the Tobacco Control Act ( Sottera, Inc. v. Food & Drug Administration 2010 ).

On September 25, 2015, FDA proposed regulations to describe the circumstances in which a product made or derived from tobacco that is intended for human consumption will be subject to regulation as a drug, device, or a combination product. The comment period for this proposed regulation closed on November 24, 2015.

Most e-cigarettes marketed and sold in the United States today contain nicotine made or derived from tobacco. Although some e-cigarettes claim that they contain nicotine not derived from tobacco, or that they contain no nicotine at all ( Lempert et al. 2016 ), there may be reason to doubt some of these claims. Currently, synthetic nicotine and nicotine derived from genetically modified, nontobacco plants are cost-prohibitive for e-cigarette manufacturers, although technological advances could eventually increase the cost-effectiveness of using nicotine that was not derived from tobacco ( Lempert et al. 2016 ). The health effects of passive exposure to e-cigarettes with no nicotine, as well as their actual use and the extent of exposure to these products, have just begun to be studied ( Hall et al. 2014 ; Marini et al. 2014 ; Schweitzer et al. 2015 ) and some states and localities are taking steps to regulate e-cigarettes that do not contain nicotine or tobacco ( Lempert et al. 2016 ).

Deeming Rule

The Tobacco Control Act added a new chapter to the Federal Food, Drug, and Cosmetic Act , which provides FDA with authority over tobacco products. The new chapter applied immediately to all cigarettes, cigarette tobacco, roll-your-own tobacco, and smokeless tobacco; and the law included “any other tobacco products that the Secretary of Health and Human Services by regulation deems to be subject to this chapter” ( Federal Food, Drug, and Cosmetic Act , §901 (b)). Therefore, to regulate e-cigarettes as tobacco products, FDA was required to undertake a rulemaking process to extend its regulatory authority to include e-cigarettes.

• Prohibitions on adulterated and misbranded products;
• Required disclosure of existing health information, including lists of ingredients and documents on health effects;
• Required registration of manufacturers;
• Required disclosure of a list of all tobacco products, including information related to labeling and advertising;
• Premarket review of new tobacco products (i.e., those not on the market on February 15, 2007);
• Restrictions on products marketed with claims about modified risk.
• Minimum age restrictions to prevent sales to minors;
• Requirements to include a nicotine warning; and
• Prohibitions on vending machine sales, unless in a facility that never admits youth.

Future Regulatory Options

• Product standards, including restrictions on flavors;
• Restrictions on promotion, marketing, and advertising, and prohibitions on brand-name sponsorship of events;
• Minimum package sizes;
• Prohibitions on self-service displays;
• Child-resistant packaging and the inclusion of health warnings; and
• Regulation of nicotine levels in products.

Despite this broad authority, FDA is prohibited from certain regulatory actions, even if those actions may be appropriate for the protection of public health. Specifically, FDA generally cannot restrict tobacco use in public places, levy taxes on tobacco products, prohibit sales by a specific category of retail outlet (e. g ., pharmacies), completely eliminate nicotine in tobacco products, require prescriptions for tobacco products unless it is marketed for therapeutic purposes, or establish a federal minimum age of sale for tobacco products above 18 years of age. Thus, even if FDA fully exercises all of its existing authority over e-cigarettes, regulation will still need to be complemented at the state and local levels, including efforts previously shown to be effective for conventional tobacco products, such as comprehensive smokefree laws at the state and local levels, pricing strategies, raising the minimum age of sales to minors to 21, and high-impact countermarketing campaigns. In the current context of rising rates of use by youth, localities and states can also implement policies and programs that minimize the individual- and population-level harms of e-cigarettes (see Chapter 5 ).

This chapter presents the major conclusions of this Surgeon General’s report and the conclusions of each chapter. E-cigarettes are presented within their historical context, with an overview of the components of these devices and the types of products. In 2016, FDA announced its final rule to regulate e-cigarettes under the Family Smoking Prevention and Tobacco Control Act. The chapter outlines options for the regulation of e-cigarettes, particularly as they relate to youth and young adults, based on successful smoking policies. The need to protect youth and young adults from initiating or continuing the use of nicotine-containing products forms a strong basis for the need to regulate e-cigarettes at the local, state, and national levels in the future.

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Vaping now more common than smoking among young people – and the risks go beyond lung and brain damage

Associate Professor of Pharmacy, Swansea University

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Amira Guirguis does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

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Vaping is now more common than cigarette smoking among young people, according to a new report coordinated by the University of Glasgow and commissioned by the World Health Organization.

This echoes research that has found the popularity of vaping among young people in the UK has surged in recent years. The number of children experimenting with vapes increased from 7.7% in 2022 to 11.6% in 2023, according to a survey conducted by anti-smoking charity, Ash.

Most of these children wanted to try vaping “out of curiosity” and were aware of the promotion of vapes in shops and online. Other motivations for using vapes included the ease of obtaining them, the flavours (young people are particularly attracted to fruity or dessert flavours) and help connecting with peers.

But vaping comes with many risks to young people, including harm to the lungs and brain.

Adolescence is a delicate period for the development of the brain. During this time, the brain grows, changes and forms new connections. The parts that control emotions and reward develop faster than those that help with planning and self-control. This can lead to teens taking more risks , such as vaping.

Nicotine, which is contained within vapes, affects teens differently to adults, as their brains are more sensitive to it. Brain receptors affected by nicotine are important for learning and addiction . Even low levels of nicotine exposure can make teens more likely to get addicted to other substances, experiment with risky behaviour , or develop mental health problems .

Nicotine can have long-lasting effects on the adolescent brain. Nicotine exposure can harm a young person’s ability to learn and focus, and make them more likely to act impulsively when they reach adulthood.

Even a small amount of nicotine can be risky for teens who are predisposed to conditions such as asthma, making them more sensitive to stress and possibly leading to mood problems later in life.

Young people who vape may be more likely to start smoking and find it harder to quit any nicotine use at all. And using vaping products alongside other products containing nicotine, like cigarettes, for example, may be even worse for their health.

Hidden risks

There are many less obvious risks to vaping too. The chemicals in vape liquids – including various toxins, heavy metals and possibly even radioactive polonium – may be harmful. The ingredients, how much of each is used and the temperature to which they’re heated can also affect what ends up in the vapour.

Some vapes may also deliver more nicotine than the user expects. This could be because of the specific mix of ingredients different brands put in the vape liquid.

The variety of flavourings in vapes is concerning, especially for teens. With over 7,000 flavours on the market such as fruit, candy floss, mint and chocolate, vapes are designed to be appealing to young people. A 2023 US study found teens are especially drawn to the more fruity flavours.

But these flavourings might also damage the lungs, potentially causing a serious condition called “popcorn lung” or bronchiolitis obliterans . This is a condition that affects the smallest airways of the lungs and can lead to coughing and shortness of breath.

There’s also some evidence that these flavourings, which are often highly concentrated in the vape aerosol, can harm cells in the body.

The Flavor and Extract Manufacturers Association is the national body representing the flavour industry in the US. It has raised concerns about how well vape flavourings are tested for safety, particularly for inhalation purposes.

This is important because some flavourings, like diacetyl , which can be used to give a butter-like flavour to food, seem harmless when you eat them but can cause serious lung problems if inhaled. This is a chemical linked with popcorn lung, which has been seen in workers exposed to high levels of diacetyl in food factories. As a result, major popcorn manufacturers have removed diacetyl from their products. But it is still available in vapes.

The process of extracting nicotine from tobacco can leave behind other chemicals like nornicotine and residues such as cotinine . And improper handling or storage of these substances can create impurities that are harmful to health.

Even if a vape liquid is advertised as being nicotine-free, it might still contain chemicals called nitrosamines , which are known to cause cancer.

Is a ban on disposable vapes enough?

The forthcoming ban on disposable vapes in England, Scotland and Wales may not be enough to deal with the problem. With more than 400 vape brands already on the market, a more comprehensive approach is needed.

This should include a crackdown on adults buying vapes for young people and prominent health warnings displayed both online and in stores that are as clear as those on cigarette packs.

Read more: To stop teenagers vaping they need to see it as cringe, not cool

We also need restrictions on flavours that target young people, stricter age verification for all vape sales and regulations that cover not just the nicotine content but also the ingredients and packaging of nicotine-free vapes.

The continued monitoring of the safety of these products is also vital, particularly in light of the loopholes exploited by “rogue firms” providing children with complimentary samples of nicotine-free vapes.

Anyone considering vaping as a way to quit smoking should aim to eventually stop vaping altogether, not just switch one habit for another. Vaping isn’t risk free for non-smokers and can have harmful health effects, especially on young people.

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Young adults who started vaping as teens still can't shake the habit.

John Daley - Colorado Public Radio

Many young people who started vaping nicotine as teens several years ago haven't quit the habit, data show. Daisy-Daisy/Getty Images hide caption

Many young people who started vaping nicotine as teens several years ago haven't quit the habit, data show.

G Kumar's vaping addiction peaked in college at the University of Colorado, when flavored, disposable vapes were taking off.

The disposables would have more than a thousand puffs in them. "I'd go through, let's say, 1,200 puffs in a week," said Kumar, who uses they/them pronouns.

Vaping became a crutch. Like losing a cell phone, losing a vape pen would set off a mad scramble. "It needs to be right next to my head when I fall asleep at night and then in the morning I have to thrash through the sheets and pick it up and find it," Kumar recalled.

They got sick often, including catching COVID — and vaping through all of it.

Kumar, now 24, did end up quitting. But many of their generation can't shake the habit.

"Everyone knows it's not good for you and everyone wants to stop," said CU senior Jacob Garza who works to raise awareness about substance use as part of the school's Health Promotion program.

"But at this point, doing it all these years ... it's just second nature now," he said. "They're hooked on it."

Shots - Health News

They're illegal. so why is it so easy to buy the disposable vapes favored by teens.

For years, slick marketing by e-cigarette companies, and the allure of sweet, fruity or even candy-like flavors and names, led teens to try vaping. As more high schoolers and even younger kids picked up the behavior, doctors and researchers warned it could lead to widespread addiction, creating a 'Generation Vape.'

Now, new data about substance use among young adults suggests that many of those former teen vapers haven't quit.

Vaping use drops among teens, rises among young adults

In Colorado, the share of those aged 18 to 24 who regularly vaped rose by about 61% from 2020 to 2022 – to nearly a quarter of that age group.

"That's an astounding increase in just two years," says Dr. Delaney Ruston , a primary care physician and documentary filmmaker.

Nationally, vaping rates for young adults increased from 7.6% in 2018 to 11% in 2021 .

Disposable electronic cigarette devices displayed for sale on June 26, 2023. While most flavored disposables are officially banned in the U.S., they continue to be sold. Rebecca Blackwell/AP hide caption

Disposable electronic cigarette devices displayed for sale on June 26, 2023. While most flavored disposables are officially banned in the U.S., they continue to be sold.

Research has shown nicotine is highly rewarding to the brains of young people.

"It's not surprising that many of them start in high school for social reasons, for all sorts of reasons," says Ruston, whose latest film is Screenagers Under the Influence: Addressing Vaping, Drugs, and Alcohol in the Digital Ag e . "And many of them now — we're seeing this — have continued to college and beyond."

Meanwhile, vape rates have actually dropped among Colorado high schoolers, said Tiffany Schommer, the tobacco cessation supervisor with Colorado's state health department.

At one point, before the pandemic, Colorado led the nation in youth vaping, topping 37 states surveyed for use of electronic cigarettes among high school students.

Vaping peaked among minors in Colorado in 2017 with 27% of Colorado youth reporting they had vaped in the past month, according to the Healthy Kids Colorado Survey . But by 2021, the most recent year for which there's data, that dropped to 16%.

Nationally vaping rates among high schoolers dropped from 28% in 2019 to 12.6% in 2023 , according to the Annual National Youth Tobacco Survey.

But for many young people who started vaping at the height of the trend, a habit was set.

"E-cigarette use has increased, particularly among people who have never smoked [traditional cigarettes,]" said Schommer. "So these are folks who started with vapes, continue with vapes."

Preliminary data indicates that almost half of those vaping 18- to 24-year-olds started vaping before they turned 18, according to the Colorado 2022 Tobacco Attitudes and Behaviors Survey.

'They weren't able to stop.'

At Children's Hospital Colorado, pediatric pulmonologist Dr. Heather De Keyser pulls up on her screen a clouded X-ray of the lung of a young adult damaged by vaping.

"This is a patient with vaping-related lung injury," she says.

For years, doctors like her and public health experts wondered about the potential harmful impact of vaping on pre-adult bodies and brains — especially the big risk of addiction

Dr. Heather De Keyser, pediatric pulmonologist at Children's Hospital Colorado, points to the X-ray of a lung of a young adult damaged by vaping. John Daley/CPR News hide caption

Dr. Heather De Keyser, pediatric pulmonologist at Children's Hospital Colorado, points to the X-ray of a lung of a young adult damaged by vaping.

"I think, unfortunately those lessons that we were worried we were going to be learning, we're learning. The data is bearing out in that," said De Keyser, an associate professor of pediatrics in the Breathing Institute at Children's Hospital Colorado . "We're seeing increases in those young adults. They weren't able to stop."

It's no coincidence the vaping rates soared during the pandemic, according to several public health experts.

For the past couple of years, undergraduates have talked about the challenges of isolation and using more substances, said Alyssa Wright, Early Intervention program manager at Health Promotion at CU Boulder .

"Just being home, being bored, being a little bit anxious, not knowing what's happening in the world," Wright said. "We don't have that social connection, and it feels like people are still even trying to catch up from that experience."

Other factors driving addiction are the high nicotine levels in vaping devices, and "stealth culture," says Chris Lord, CU Boulder's associate director of the Collegiate Recovery Center .

"The products they were using had five times more nicotine than previous vapes had," he says. "So getting hooked on that was ... almost impossible to avoid."

As far as "stealth culture," Lord means that vaping is exciting, something forbidden and secret. "I think as an adolescent, our brains are kind of wired that way, a lot of us," Lord said.

The Juul effect

Wind the clock back half a decade and one could see the seeds of these current vaping rates.

In 2019, if you typed the word "Juul" into the search bar on YouTube, you could find an endless stream of videos of young people showing off how cool it was to use the company's sleek, high-tech-looking vaping device.

Juul packages are seen on a shop shelf on December 07, 2022. Michael M. Santiago/Getty Images hide caption

Juul packages are seen on a shop shelf on December 07, 2022.

In one video Colorado Public Radio found in 2019, two young women show how they "make parties more fun."

"We just chillin',' one says, laughing. "We vapin' and we Juul-in'."

Many of those videos are no longer available, pulled off the platform once the trend took off. Searching for Juul now brings up many videos warning of the dangers and how to talk to kids .

All over the U.S., state and local governments, including Colorado, filed suit, alleging Juul Labs misrepresented the health risks of its products.

Juul agreed to pay hundreds of millions in settlements , including a nearly $32 million settlement last year with Colorado.

Juul had become No. 1, the top e-cigarette company, the lawsuits argued, by first aggressively marketing directly to kids, who then spread the word themselves by posting to social media sites like YouTube, Instagram and TikTok.

"What vaping has done, getting high schoolers, in some cases even middle schoolers, hooked on vaping, is now playing out," says Colorado attorney general Phil Weiser , a parent of two teens himself. He said vape companies followed the tobacco industry playbook — with a similar impact on young consumers. "They're still hooked. This is a very addictive product."

Juul did not respond to requests for comment.

R.J. Reynolds, which makes another popular brand , Vuse, sent NPR this statement: "We steer clear of youth enticing flavors, such as bubble gum and cotton candy, providing a stark juxtaposition to illicit disposable vapor products."

Other big vape companies , like Esco Bar, Elf Bar, Breeze Smoke and Puff Bar didn't respond to requests for comment.

"If we lived in an ideal world, adults would reach the age of 24 without ever having experimented with adult substances. In reality, young adults experiment," said Greg Conley, director of legislative & external affairs with American Vapor Manufacturers. "This predates the advent of nicotine vaping."

The FDA banned flavored vape cartridges in 2020 in an effort to crack down on marketing to minors, but the products are still easy to find .

Debate over vaping's role in smoking cessation

One claim often made in defense of vaping is that it can help users quit cigarette smoking.

Joe Miklosi, a consultant to the Rocky Mountain Smoke-Free Alliance, a trade group for vape shops contends the shops are not driving vaping rates among young adults in Colorado.

"We keep demographic data in our 125 stores. Our average age (of customers) is 42," he says.

Vape shops sell products to help adult smokers quit, Miklosi says, with lower levels of nicotine than big companies like Juul. Miklosi claims he's talked to thousands of consumers who claimed vaping helped them quit smoking cigarettes.

But the Colorado data belies that, according to longtime tobacco researcher Stanton Glantz.

The 18-24 age group leads all age groups in regular use, and use gradually dropped with each age cohort, up to the 65+ demographic, of which just 1% use e-cigarettes.

The data are "completely inconsistent with the argument that most e-cigarette use is adult smokers trying to use them to quit," said Glantz, the now-retired director of the Center for Tobacco Control Research and Education at the University of California San Francisco.

Glantz says because of the onslaught of sleek technology, flavors, and marketing used by Juul and other companies "the kids are getting addicted younger and faster," compared to earlier decades when traditional cigarettes dominated the tobacco market.

Finding the will to quit

For recent college graduate G Kumar, now a rock climber, the impetus to quit vaping was more ecological than health-related. It was "knowing the amount of trash [from used up vape devices] that I was accumulating and the amount of money I was spending," they said.

Kumar got some help from a package of cessation literature and quitting aids from CU's Health Promotion program. It included two boxes of eucalyptus-flavored toothpicks, which tasted awful to Kumar, but provided a distraction and helped with oral cravings.

"The fact that I could just gnaw on toothpicks for weeks on end was, I think, what kept me sane," Kumar said.

It took a while and a lot of willpower to overcome the intense psychological craving, something many others in that generation know all too well.

This story was produced in partnership with CPR News and KFF Health News.

• nicotine addiction
• youth vaping
• young adults

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The UK’s smoking ban is government meddling at its worst and most pointless

Tobacco is already on its way out. The state should not deny adults the right to make personal decisions for themselves

J ust because Liz Truss and Boris Johnson – both opposed to the government’s proposed new smoking ban – hold a belief does not make it wrong. Smoking is unpleasant, but in this week’s parliamentary debate, the word nicotine could have been replaced by cannabis, alcohol, ultra-processed foods, base jumping or mobile phones for children. All have their dangers. But in each case those in favour of restrictions rely on the same argument; if something produces a burden on the state it should be banned. Personal liberty can go hang.

Rishi Sunak’s anti-smoking bill carried the same smudgy fingerprints as his bill on Rwanda. It suggested a late-night Downing Street cabal desperate for somethingeye-catching to inject into the election campaign. It does not ban anyone from smoking, despite appearances. It bans shops from selling cigarettes to an ever-expanding age cohort, currently anyone under 18, with the legal cutoff increasing by one year each year. People born in or after 2009, in other words, will never be able to legally buy a cigarette in Britain. The bill’s target is shopkeepers, charged with juggling the ID cards of hordes of adult purchasers and presumably proxy buyers. The smugglers must be cheering.

So far Britain’s efforts to curb smoking – built on the nudge principle – have been remarkably effective. This has been achieved, as many economists would advise, by working on demand rather than supply. Cigarette use has fallen over the past half-century from about 45% of the population in 1974 to about 12% today and it continues to fall. The method has been to stop smoking indoors, in public enclosed spaces and around children. Advertising has been banned, vending machines abolished and children cannot buy cigarettes. The introduction of vaping, though controversial when it’s young people doing it, is understood to have helped accelerate the fall in smoking, as per the drug policy charity Transform. That vaping can reduce smoking is backed up by data from Australia, where vapes were effectively banned in 2021 and the result has been no cut in smoking – indeed, there’s been a small rise.

For all that, more than 6 million Britons still smoke, their burden on the NHS relieved only by their paying £10bn in tobacco taxes and dying – on average – younger. Despite the comfort smoking has long brought to many people – not everyone is a nicotine addict – there must be a public interest in discouraging its consumption. In its lengthy study of this debate, Transform comes down firmly in favour of simply extending what has worked. When in 2007 Britain raised the age from 16 to 18 it led to an estimated 30% fall in smoking by that age group, a remarkable achievement. In the US, raising the age to 21 in 2019 led to an even greater fall of 39%. A similar raise to 21 is surely what the British government should now do. Unlike Sunak’s staggered ban, which may take five years to take effect, this change could be introduced at once. The only other country to propose his “ID-card ban” has been New Zealand. Its unpopularity and a change of government have seen it abandoned .

We also see the heavy hand of the state in Britain’s failed drugs policies. The global “war on drugs” has been an unmitigated disaster, built as it was on the thesis that demand would end if supply was stamped out. The only regime to prove remotely effective in curbing supply is the Taliban in Afghanistan – and that may not last. Politicians everywhere have preferred to see gangsters triumph, crime soar, jails become crammed and their children ruined, rather than show the guts to decriminalise , regulate and control the hugely lucrative and dynamic drugs industry.

Governments across Europe – most recently in Germany – are testing how to handle recreational and other sorts of drug. They are experimenting with licensing, taxation, product regulation, publicity and public education. Some approaches work, some do not. The British government has adopted a workable policy on the smoking of tobacco by young people. Its record on nicotine control is widely regarded as a success – as its record on other narcotics is a raging failure. As Transform points out, “Tobacco control … is one key aspect of drug policy where the UK has not been shockingly poor by global standards.” The reason appears to be that it has treated “smoking as a public health challenge, led by health agencies, rather than an enforcement challenge led by the Home Office”. Sunak’s smoking ban would have the same defects as the cannabis ban. Complicated government is always bad government.

Tobacco control offers an intriguing testing ground for what is now the fast-liberalising market for drugs across Europe. Realistic and fair regulation will be hard but it must come in if millions are not to die prematurely. The misuse of opioids is now approaching pandemic status across the US.

At every turn, the state is inviting itself to delve ever deeper into the lives and ethics of its citizens – accusations that are constantly thrown at authoritarian governments. It seeks to relieve us of responsibility for personal decisions and deny us freedom of choice. It rules on the food we eat and the drinks we drink, on the right to criticise and on how we discipline or indulge our children. Britain does not need gimmicks such as cigarette passports. Tobacco is a menace but one that’s on the way out. Other addictions should now claim our attention.

Simon Jenkins is a Guardian columnist

• Tobacco industry
• Young people

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Vaping and Its Negative Aspects Essay

Introduction, attention-arousing and orienting material.

Vaping has become a curse of the recent decade. Vapes are better than nicotine-containing cigarettes. Vapes do not harm the health of a smoker. Vapes are about vaping, not smoking. As one popular vape-producing company puts it, “live long and vape strong”. It seems that vapes create a new reality in which smoking could be safe. Well, what if I say that, in the US, in one week 12 people died because of vaping and 805 people were diagnosed with the breathing illness related to vaping (Pesce par. 1). If these statistics are not enough to give up vaping, the goal of the current speaker is to persuade that vapes are not as warm and fuzzy as companies want us to believe.

Credibility

Vaping is regarded as an escape for smokers who try to give up their addiction since the latter could substitute the former. Still, there are numerous sources that vaping is a decent and safe habit. The argument against vaping is backed by the results of the researches, the viewpoints of medical experts, and the experience of vapers. The importance of this topic is undeniable since even underaged people become addicted to vapes.

Thesis Statement

Vaping has numerous devastating effects and did not worth doing.

Preview of main points

There are two major reasons to give up a habitude of vape. Firstly, vaping is addictive and undermines the ability to self-control. Secondly, usage of a vape, even if it is nicotine-free, poses a health hazard and leads to diseases of the respiratory system.

Vaping is addictive

It is a well-known fact that there are numerous kinds of vaping liquids. They have various chemical compositions, tastes, and smells. Some of them might contain nicotine, while others are free of it. The problem is that vaping causes addiction in any case.

One of the reasons for this is that vapes are regarded as tools to socialize and make new acquaintances (Levin par. 21).

In essence, new friends and a higher circle of socialization is positive outcome of vaping.

However, the issue lies in the fact that young people that are shy to make friends, for instance, during classes, start vaping to fit in with the team.

• Vice versa, if an individual intends to give up vaping, he or she might postpone this idea because of the fear to distance herself from the friends who use vapes.
• In the interview with the 21-years old man, Levin illustrates how strong the addiction might be (par. 16). Josh Evans avows that he inhales the vapors even though sometimes it makes him feel physically bad and fail to fight against vaping (Levin par.16).
• The final point worth being mentioned is that addiction to vaping leads to more serious addictions in the long-term perspective.

In two years, the number of young adults using vaping cartridges with the flavor of cannabis or nicotine increased more than twice (Pesce para.2).

According to the President of the Campaign for Tobacco-Free Kids, Matthew Myers, people that become addicted to vapes or e-cigarettes at a young age, grow into heavily smoking adults (Lemons 17).

(Transition: The fact that vapes triggers addiction would not be that important if it were not for the health hazard.)

Vaping is dangerous for health

Blaha informs that all lung fluid samples of people ill with “e-cigarette, or vaping, product use associated lung injury (EVALI)” show the presence of vitamin E acetate (par 6.).

From this, it could be inferred that vaping liquids contain chemicals that cause diseases of the respiratory system. Thus, even nicotine-free vapes could have a devastating effect on health.

Another point of concern about vaping is that hitherto remains a lot of doubts about how certain chemicals in liquids affect health (Blaha par. 9). Nevertheless, some studies confirm that vaping leads not only to asthma but also to cardiovascular disease (Blaha par.9).

Therefore, it could be argued that vaping remains an insufficiently studied phenomenon. The absence of a clear understanding of the consequences of vaping, as well as PR campaigns of brands that produce vapes and liquids, give a reason to think that vaping does not affect health. At the same time, the growing number of young people with breathing diseases makes them think that vaping is not as good as it might seem at the first sight.

(Transition: As you can notice, vaping has a significant number of disadvantages that should motivate people either not to try it or give up the habit.)

Summary statement

Vaping is not only addictive but also challenges the well-being of a vaper. In the scientific community, there is no common opinion on the effect of the chemicals that are included in the composition of vaping liquids. Notwithstanding this fact, the example of people diagnosed with EVALI proves that vaping represents a threat and that life would be better without this addiction.

Concluding remarks

Still, it is important to remember that our health and quality of life depend on our own choices. Vapes were not created by nature and human beings survived for centuries without smoking and vaping. I will leave you with the question: if the necessity to vape was not put in our bodies and minds by nature, do we need it?

Works Cited

Blaha, Michael Joseph. “5 Vaping Facts You Need to Know.” Health Conditions and Diseases , 2020. Web.

Lemons, Jane Fullerton. E-Cigarette Dilemma . CQ Press, 2019. Web.

Levin, Dan. “Vaping on Campus: No Parents, No Principals, a Big Problem.” The New York Times , 2019. Web.

Pesce, Nicole Lyn. “These Charts Show the Shocking Number of High School and College Students Who Vape.” Market Watch , 2019. Web.

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IvyPanda. (2023, October 31). Vaping and Its Negative Aspects. https://ivypanda.com/essays/vaping-and-its-negative-aspects/

"Vaping and Its Negative Aspects." IvyPanda , 31 Oct. 2023, ivypanda.com/essays/vaping-and-its-negative-aspects/.

IvyPanda . (2023) 'Vaping and Its Negative Aspects'. 31 October.

IvyPanda . 2023. "Vaping and Its Negative Aspects." October 31, 2023. https://ivypanda.com/essays/vaping-and-its-negative-aspects/.

1. IvyPanda . "Vaping and Its Negative Aspects." October 31, 2023. https://ivypanda.com/essays/vaping-and-its-negative-aspects/.

Bibliography

IvyPanda . "Vaping and Its Negative Aspects." October 31, 2023. https://ivypanda.com/essays/vaping-and-its-negative-aspects/.

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