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E-cigarette and traditional cigarette product waste

While cigarettes still comprise almost 90% of all tobacco sales globally as of 2020 (except for South Asia), other tobacco products, especially electronic cigarettes, also weigh heavily on the environment. Electronic cigarette components (and cigarette butts) can leach contaminants into the soil, water, and air. While there are few studies of the prevalence of e-cigarette waste in the environment, it is probable that the recent increase in e-cigarette usage, as of 2021, has been accompanied by an increase in littering of e-cigarette waste, with an associated chemical contaminant release. Disposed e-cigarettes are also sources of metal contamination to the environment, both directly as the result of the breakdown of electronic components and indirectly via contaminated e-liquids.

Aerosol production during e-cigarette use results in air contamination from exhaled and third-hand pathways. Cigarette combustion results in air contamination from side-stream, exhaled, and third-hand pathways. The chemical by-products of tobacco product use contaminate wastewater effluents, landfill leachates, and urban storm drains. The widespread detection of nicotine and cotinine in the environment illustrates the potential for large-scale environmental impacts of tobacco product waste. To support effective policies to reduce the negative economic externalities of e-cigarette pollution, a more comprehensive picture of direct and indirect environmental costs of e-cigarette use and disposal is needed.

The rise of e-cigarettes in industrialized countries is changing the composition of the environmental harms of tobacco. Because these products are composed of low-value but sophisticated electronics, the environmental costs from manufacturing e-cigarettes may be substantially more severe than cigarettes per unit. E-cigarettes made in different countries are manufactured according to the standards of the manufacturer's country, and do not always conform to laws for exposures to metals and other toxicants in the countries they are used. It does not appear as if any cradle-to-grave industrial ecology has been undertaken to minimize the amount of ecological impact of e-cigarette manufacturing and disposal. E-cigarettes that are thrown away that end up in landfills is a rising public health concern. Quitting vaping and is beneficial for the environment.

Background

Tobacco product use is extensive and continues to grow worldwide, according to a 2021 review. Over six trillion conventional combustible cigarettes are produced and consumed globally each year. In addition, the use of electronic cigarettes has increased dramatically, and sales of e-cigarettes are growing rapidly, as of 2021. In the US, approximately 60 million e-cigarettes and refills are sold annually, and one-third of these are designated single use, as of 2021. E-cigarettes are especially popular among youth and young adults. Other practices that are growing in popularity include waterpipe smoking and the use of heated tobacco products, which are newer forms of nicotine delivery systems approved by the US Food and Drug Administration.

The impacts of cigarette smoking on human health are widely known, with tobacco-attributable deaths of around eight million per year globally, or one in ten deaths annually. A less recognized effect of tobacco product use and disposal is the indirect impact on human welfare from environmental pollution, which may impair the provision of critical ecosystem services such as clean water, clean air, and food production. Smoke, tar (the particulate fraction of tobacco smoke), and waste from cigarettes and e-cigarettes contain numerous toxic compounds, including nicotine, polycyclic aromatic hydrocarbons, and metals. Trillions of pollutant-containing cigarette butts are discarded to the environment annually, making cigarette butts ubiquitous waste items worldwide, especially in coastal regions.

Cigarette butts can leach pollutants into the soil, surface water, and groundwater as they age and break apart, exposing biota to a range of contaminants, some of which may bioaccumulate in food webs. Cigarette butts themselves largely consist of filters made of cellulose acetate, a synthetic polymer that is resistant to biodegradation, making cigarette butts significant sources of fibrous plastic pollution to the environment. Waste associated with e-cigarettes includes replaceable capsules with concentrated nicotine residuals, batteries, and electronic circuitry that can also leach pollutants into water and soil. Areas frequented by adolescents and young adults, including schools, are hot spots for e-cigarette debris, much of which originates from the use of flavored tobacco products.

Contaminants

Nicotine

The alkaloid nicotine (3-(1-methyl-2-pyrrolidinyl)pyridine) is one of the most abundant chemicals in tobacco products. Nicotine contamination pathways to environments exist throughout the tobacco life cycle, and the passage of nicotine and its metabolites, primarily as cotinine and trans-3’-hydroxycotinine, into human wastewater streams.

Due to its historical use as a fumigant and pesticide, the vapor pressure of nicotine has been well-characterized. At ambient temperatures, its volatility is relatively low (~5.6 Pa at 25 °C). This is about 35 times less than the vapor pressure of 1,4-dichlorobenzene (1,4-DCB), a common ecotoxicity benchmark chemical; however, like most compounds, the vapor pressure of nicotine increases appreciably with the increasing temperatures associated with tobacco combustion. Whether nicotine is dispersed in significant quantities as a vapor depends on environmental conditions. The nicotine molecule has two basic nitrogen groups (pKa1 = 3.12, pKa2 = 8.02 at 25 °C) and can exist as a neutral free base, or as monoprotonated and diprotonated salts. The free-base form of nicotine has a greater tendency to partition from the water or solid phase to the air phase. For example, an ammonia addition to cigarette tobacco can elevate the pH during tobacco combustion, resulting in a decrease in nicotine partitioning onto smoke particles as speciation shifts to the more volatile, free-base form.

In aquatic systems, nicotine fate and transport have not been well studied. In most natural waters, the monoprotonated form is dominant and water miscible; however, the fraction of free-base increases under more alkaline conditions. The free-base form is relatively soluble in water, but also retains some hydrophobicity as indicated by its significant octanol–water partitioning coefficient value (log Kow~1.2), that for comparison, is lower than that for the benchmark nonpolar toxicant 1,4-DCB (log Kow~3.4). The partitioning of the nicotine from water to environmental solids, or its bioconcentration potential, is strongly affected by pH. Under acidic to neutral conditions, nicotine is ionized and less prone to partition into organic matter or lipids (log Kow < 0.2). Nicotine tends to adsorb to charged surfaces such as bentonite clays and engineered ion exchange resins. Under basic conditions, significant nonionized, free-base nicotine is present and more prone to partition into organisms. There is limited information regarding the abiotic and biotic transformations of nicotine in the environment. Relatively rapid photocatalytic oxidation has been demonstrated under laboratory conditions. Half-life values estimated in a laboratory study of monoprotonated nicotine (pH 6.5–7.0) ranged from months to a year. A study by the R.J. Reynolds Tobacco Company reported nicotine hemisulfate biodegradation half-lives of ~3 d in aerobic soil slurries and 0.5 d in unacclimated activated sludge incubations, which likely promote higher degradation rates relative to actual, more static environmental conditions.

Tobacco-specific nitrosamines

Nicotine and other tobacco alkaloids produce additional toxic and potentially carcinogenic transformation products, tobacco-specific nitrosamines, that are formed in the post-harvest curing process and during combustion. During the tobacco curing process, tobacco-specific nitrosamines are products of reactions between nicotine and nitric acid. The main tobacco-specific nitrosamines of concern in tobacco are nitrosoanabasine (NAB), nitrosoanatabine (NAT), N’-nitrosonornicotine (NNN), and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). All four have been found in substantial levels in tobacco smoke and in lesser amounts in e-cigarette aerosol. NNN and NNK are the most carcinogenic. Tobacco includes other tobacco-specific nitrosamines, including nitrosamines 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), 4-(methylni-trosamino)-4-(3-pyridyl)-1-butanol (iso-NNAL), and 4-(methylni-trosamino)-4-3-pyridyl) butyric acid (iso-NNAC). Tobacco smoke tar is known to include non-volatile nitrosamines.

Tobacco-specific nitrosamines are also formed in surface-catalyzed reactions on fine particulate matter on indoor surfaces producing third-hand smoke hazards. Third-hand smoke encompasses the pollutants on surfaces and in dust after tobacco has been smoked in a closed environment. Ramírez et al. found tobacco-specific nitrosamines in nonsmokers’ homes in addition to smokers’ homes, indicating that ambient air can act as the common source. Little is known about the transport and fate of tobacco-specific nitrosamines in outdoor air and surfaces, and in aquatic ecosystems.

Polycyclic aromatic hydrocarbons

Polycyclic aromatic hydrocarbons are organic compounds comprised of multiple aromatic rings and are produced by the incomplete combustion of organic matter. Mainstream and second-hand smoke contain numerous polycyclic aromatic hydrocarbons that mainly reside in the particulate tar fraction. Tobacco smoke tar contains around 0.02% polycyclic aromatic hydrocarbons by mass. While many polycyclic aromatic hydrocarbons in tar are carcinogenic, they alone do not account for the toxicity of tobacco smoke tar, pointing to the complex nature of this substance. The three most abundant polycyclic aromatic hydrocarbons in tobacco smoke tar are the low molecular weight two-ring naphthalene, and the three-ring polycyclic aromatic hydrocarbons fluorene and phenanthrene. The high molecular weight prototypic polycyclic aromatic hydrocarbon benzo[a]pyrene, a five-ring polycyclic aromatic hydrocarbon, is classified as a Group 1 carcinogen to humans. Polycyclic aromatic hydrocarbons are nonpolar and hydrophobic, and many polycyclic aromatic hydrocarbons, especially those of lower molecular weight, are reasonably water soluble, volatile and biodegradable by soil and aquatic microorganisms. Polycyclic aromatic hydrocarbons tend to accumulate on particles in environments, such as smoke, dust, soil and sediment that facilitate polycyclic aromatic hydrocarbon transport in the atmosphere and in soils and groundwater. Once in environments, the fate of the polycyclic aromatic hydrocarbons depends on the physical properties of the specific polycyclic aromatic hydrocarbon, temperature and moisture conditions. Polycyclic aromatic hydrocarbons can persist for decades in environments when they are strongly sorbed to soil and less bioavailable, or present at higher concentrations or agglomerated states in contaminated industrial sites.

Laboratory and field studies demonstrate that polycyclic aromatic hydrocarbons are primary tobacco-related contaminants and that cigarette butts release polycyclic aromatic hydrocarbons into environments, presumably from captured tar. Dobaradaran et al. measured 16 polycyclic aromatic hydrocarbons in freshly smoked cigarette butts, week-old cigarette butts from city streets, and aged cigarette butts in urban river areas, and found that concentrations decreased with cigarette butt age. The results also showed that the concentrations of polycyclic aromatic hydrocarbons with fewer rings decreased with time, a finding attributed to the relatively greater water solubility and volatility of these compounds. For example, mean levels of naphthalene (two-ring polycyclic aromatic hydrocarbon) dropped from 5.8 to 2.9 to 0.8 mg/kg in each of the three cigarette butt samples. In contrast, levels of the potent carcinogen benzo[a]pyrene (five-ring polycyclic aromatic hydrocarbon) remained constant at ~1.3 µg/g. Being a by-product of tobacco combustion in cigarettes, the range of polycyclic aromatic hydrocarbon molecules associated with cigarette butts has substantial overlap with that from other sources, such as fuel combustion in urban settings; however, a study of roadside environments, high-density disposal sites for cigarette butts, has identified significant levels of cigarette butt-derived polycyclic aromatic hydrocarbons in these areas, particularly the smaller 3- and 4-ring polycyclic aromatic hydrocarbons along with benzo[a]pyrene. While these studies clarify the general behavior of polycyclic aromatic hydrocarbons in cigarette butts, the release rates of polycyclic aromatic hydrocarbons from cigarette butts and their persistence with aging in environments are not well understood.

Metals and metalloids

The tobacco plant, Nicotiana tabacum, can readily accumulate metals from soil. As a result, manufactured tobacco products such as cigarettes can be enriched in metals, and their subsequent consumption and disposal can be an additional source of metal pollution to the environment. While essentially all elements present in soil can be found in tobacco plant tissue and many of these are of concern regarding human exposure via cigarette smoke, a subset are also of potential concern to the natural environment. These include the metals cadmium, chromium, lead, mercury, nickel, and zinc, and the metalloid arsenic. All these elements occur naturally in soil, but elevated concentrations are attributed to the presence of underlying marine sediments, agronomical applications of municipal or industrial wastes, the presence of mine tailings or smelter residues, excessive use of naturally contaminated phosphorus fertilizers, and atmospheric deposition.

The bioavailability of metals is commonly linked to their dissolved concentrations in soil solutions or aqueous environments. Metals are surface reactive and sorb to organic and inorganic surfaces in soils and sediments. Cadmium, lead, nickel, and zinc are most commonly present in solution as divalent cations, both as free aqueous ions and complexed with organic or inorganic ligands. The aqueous solubility of these solutes increases with a decreasing solution pH. Arsenic and chromium can exist in multiple oxidation states under typical environmental conditions. Lower oxidation state species tend to follow the general pH-dependent trend seen for the divalent cations. Higher oxidation state species typically complex with oxygen to form oxyanions. These negatively charged species routinely exhibit increasing solubility, mobility, and bioavailability with an increasing solution pH in soil, sediment, and aquatic environments.

Upon tobacco combustion, metals can be released in smoke and tar, captured by the cigarette butt filter material, or remain in the resulting ash. The fraction of these elements remaining in the filter is subject to leaching into terrestrial and aquatic environments. Several metallic materials are also used in the construction of e-cigarettes, resulting in the presence of toxic metal ions in e-liquids and in vapors produced by these devices. The inappropriate disposal of e-cigarettes can pose a significant source of toxic metals to both terrestrial and aquatic environments, as do many electronic consumer devices. The association of metals with nanoparticles is notable, as such particles may be more readily transported through soil and sediment than relatively reactive metals that are fully dissolved. The amount of toxic metals released globally to the environment from the leaching of cigarette butts may be significant. Chevalier et al. report that cigarette butts could release millions of tons of chromium and nickel into the environment annually.

Contaminant sources

Electronic cigarettes

E-cigarettes are battery-operated devices that heat a liquid containing nicotine, propylene glycol or glycerin, and flavoring agents into an inhaled aerosol. E-cigarettes have rapidly increased in popularity, particularly among youth and young adults. E-cigarettes range in appearance from small plastic pens or universal serial bus (USB) keys to larger customizable hand-size "tank" devices. Most e-cigarettes share similar components, including: a battery, a heating element and aerosolization chamber called an atomizer, an e-liquid reservoir, and a mouthpiece. Devices range in reusability and may have rechargeable or replaceable batteries, replaceable atomizers, and refillable or single-use disposable reservoirs commonly called “pods.” Non-reusable one-piece disposable e-cigarettes are becoming popular because of their low cost and exemption from flavor restrictions.

While there are few studies of the prevalence of e-cigarette waste in the environment, it is probable that the recent increase in e-cigarette usage, as of 2021, has been accompanied by an increase in littering of e-cigarette waste, with an associated chemical contaminant release. A study at San Francisco Bay Area high schools in the US showed that e-cigarette products comprised 19% of smoking litter found around exterior perimeters, second only to cigarette butts. Littering of e-liquid containers from e-cigarettes poses a particularly serious threat of environmental pollution because they can contain high concentrations of residual nicotine. Besides nicotine, e-liquids contain numerous additives for flavoring, many of which are known to be toxic or have suspected or unknown toxicities. These include various aldehydes, tobacco-specific nitrosamines, benzyl alcohol, glycerol-1,2-diacetate, and dioxolane compounds. While the level of toxicants in e-cigarette vapors may be lower than in combustible tobacco smoke as they do not include tobacco combustion products, vapors from e-cigarettes are potent sources of environmental air pollution, particularly aldehydes and carbon monoxide.

Disposed e-cigarettes are also sources of metal contamination to the environment, both directly as the result of the breakdown of electronic components and indirectly via contaminated e-liquids. Common metals in the components of e-cigarette products include aluminum, barium, cadmium, chromium, copper, iron, lead, nickel, silver, tin, and zinc. In leaching tests of e-cigarette components, lead in the resultant leachate exceeded US regulatory thresholds for hazardous-waste designation by up to ten-fold. Toxic metals have also been detected in e-liquids with levels increasing after use, indicating that metals can seep into e-liquids. Metals and metalloids have been detected in e-cigarette atomizers and components that heat and vaporize e-liquids. The potentially cytotoxic metal, copper, was detected in e-cigarette aerosols at concentrations ~6 times higher than combustible cigarette smoke. Additional toxic or potentially toxic compounds have also been detected in e-cigarette filters, mouthpieces, rubber stoppers, and pod plastic.

Waste management systems

Several studies have measured nicotine metabolites in the influent and effluent at wastewater treatment plants. The primary source of these chemicals is excretion from smokers. Nicotine absorbed into the body from tobacco products is metabolized into a range of compounds in the human liver, mainly cotinine and trans-3’-hydroxycotinine, and released mostly in urine. As a percentage of the absorbed nicotine, urine typically contains ~5–10% nicotine, ~10–30% cotinine, ~35–45% trans-3’-hydroxycotinine, and a range of less common cotinine metabolites. A typical nicotine equivalent excretion rate for a smoker, assuming 1.25 mg nicotine absorption per cigarette and a 12-cigarettes-per-day smoking rate, is around 15 mg/d.

A comprehensive assessment of wastewater treatment plants in Zurich, Switzerland, measured cotinine at 1.5–2.9 µg/L and 3′-hydroxycotinine at 3.0–9.5 µg/L in wastewater influent. Nicotine was measured in a wastewater treatment plant near Barcelona, Spain, at concentrations ranging from 100–3250 µg/L. In many studies, researchers observed substantial removal of nicotine, cotinine, and 3′-hydroxycotinine during the treatment process. Because nicotine in wastewater can originate from other sources (e.g., discarded cigarettes, nicotine patches, and nicotine gum) and is potentially more degradable in the environment, cotinine is considered a better biomarker of cigarette consumption. Some trace metabolites, such as N-formylnornicotine, appear resistant to degradation during wastewater treatment, and therefore could also be used as biomarkers of cigarette pollution. Studies have also tracked nearby receiving waters and discovered nicotine and its metabolites in surface waters. In a comprehensive assessment of surface waters in the US, cotinine was one of the five most commonly detected chemicals, underscoring the ubiquitous nature of tobacco use pollution in the environment.

Several other waste management-related sources have been linked to contamination of groundwater with pollutants such as nicotine and cotinine, which could be related to the use and disposal of cigarettes. Compared to surface waters, groundwater pollution appears less extensive; however, nicotine and cotinine have been observed in groundwater near septic tank discharges. The discharge of reclaimed tertiary-treated wastewater used for irrigation and groundwater recharge can also be a source of cotinine in the environment. Another source of anthropogenic pollutants to groundwater is landfills, especially systems that lack modern leachate containment systems. Two studies of legacy pollution from unlined landfills in the US detected cotinine in the groundwater, but the sources could not be conclusively linked to the disposal of tobacco product waste. Other studies have detected nicotine and cotinine in leachate collected from lined domestic and industrial landfills.

There is a growing acknowledgment that sewers and stormwater collection systems are potential sources of water-based pollutants to shallow groundwater, which in turn can contaminate deeper groundwater resources used for potable supply and hydrologically connected surface waters. In urban settings, discarded cigarette butts appear to be a significant source of nicotine to stormwater collection systems. Assessments of urban stormwater quality in the US consistently measured nicotine and cotinine. A related source, in terms of a high density of cigarette butt litter in urban environments, is roadsides. A handful of studies have shown that roadway cigarette butt litter contributes nicotine, metal, and polycyclic aromatic hydrocarbon pollution.

Environmental impacts

Microorganisms

Microorganisms include prokaryotes (Bacteria including bacteria and cyanobacteria, and Archaea), eukaryotes (Eukarya, such as fungi and protozoans), symbioses (e.g., plant root nodules, or lichens), and viruses. Such organisms respond to ambient chemicals in marine and freshwaters, soils and sediments, and waste treatment systems (i.e., all environmental compartments where cigarette waste can accumulate. As is the case for other agricultural plants, there is a diverse and dynamic microbiome associated with tobacco. This includes a wide range of microbial organisms associated with cigarettes that are known human disease pathogens. Tobacco-associated microbes introduced into the human oral cavity may change microbiomes as occurs with the use of smokeless tobacco, tobacco smoking, and vaping. Studies also point to differences in the gut microbiomes in adult smokers compared to non-smokers, as well as infants and children exposed to third-hand smoke.

Microbial biodegradation of tobacco waste chemicals may influence the fate and environmental risk of such chemicals; however, biodegradation depends on many factors, including if the chemicals undergoing degradation are toxic to microorganisms. Nicotine is known to be toxic to higher organisms and can also be antimicrobial. Oropesa et al. found that nicotine concentrations up to 1000 μg/L were not acutely toxic to the marine bacterium Vibrio fischeri, with a no observed effect concentration (NOEC) of <200 μg/L nicotine; however, many microorganisms, including bacteria and fungi, can metabolize nicotine. For example, in soil contaminated with tobacco waste, inoculation with a nicotine-degrading bacterial strain of Pseudomonas led to these populations proliferating during biodegradation. Such introduced bacteria exploiting the nicotine in soil suggests that, where microbial nicotine metabolic pathways exist either with natural populations or those arriving with tobacco waste, associated genes could be expressed in the environment.

The complex mixture of contaminants found in cigarette butt leachate can be toxic to bacteria. Micevska et al. reported that 30 min EC50 (50% effects concentration measured via bioluminescence) values for the marine bacterium Vibrio fischeri ranged from ~100–200 cigarette butt/L for a range of cigarette brands. This may explain why cigarette butts, the most prevalent form of littered plastic, do not readily biodegrade despite evidence of the microbial metabolism of the pure cellulose acetate that comprises cigarette butts. The leachate from smoked cigarette butts has been shown to exert toxicity inhibiting biodegrading microorganisms in various aquatic microbial populations. Such toxicity may constrain nicotine and cellulose acetate biodegradation under field conditions. This was implied in a composting study of cellulose-only versus plastic (cellulose acetate) cigarette butts. Both types of smoked butts inhibited cigarette filter biodegradation, stemming from the toxic chemical milieu of leached smoke pollutants; however, in a five-year experiment of cigarette butt decomposition in various soils, after an initial phase in which chemical toxicity inhibited biodegradation, a more rapid biodegradation phase was observed. Available nitrogen was a major factor identified as potentially limiting biodegradation rates. This suggests that factors influencing the persistence of cigarette chemical pollution on various landscapes, if better understood, could be managed to accelerate biodegradation.

There is limited literature on how cigarette waste in the environment affects key ecosystem services delivered by microorganisms, such as nutrient cycling. As noted below, environmentally relevant concentrations of nicotine can impair aquatic primary producers and eukaryotic predators. Thus, population dynamics and food web interactions are at risk where environmental nicotine enters aquatic systems. Additionally, the impacts of cigarette butts on the diversity of microbial communities in the environment have recently been reported, as of 2021. Over a 96 hour exposure, marine sediments treated with smoked cigarette butts had altered microbial communities, including decreases in two taxonomic families, Cyanobacteria and Bacteroidetes, involved in photosynthetic (primary production) and organic matter biodegradation activities. Koroleva et al. assessed the effects of leachate from smoked biodegradable cellulose versus cellulose acetate cigarette butts to soil bacterial communities. Bacterial community diversity did not appear to vary significantly when comparing the butt leachate treatments to each other and to the no-treatment control. Longer-term incubations in soil could be useful to determine if differences in communities arise. The implications of microbial community taxa shifts, when they occur and if attributable to toxins released from cigarette butts, are important to understand for a broad environmental risk assessment related to tobacco product waste.

Plants

Research interest in the plant uptake of nicotine from the environment originates, in part, from numerous detections of nicotine in plant tissues in phylogenetically diverse food crops and other plant-derived products, such as spices and teas. These plants are not known for endogenous nicotine synthesis, and elevated nicotine concentrations in their tissues can be found under conditions where nicotine-containing insecticides had not been applied. Elevated nicotine levels in commodity plants are a concern due to the human health risks, which may result in the commodity being pulled from the market, causing economic losses for farmers and distributors. In response to unexpectedly high levels of nicotine contamination, the European Union temporarily increased its maximum nicotine residue level in commodity crops so as to not overly burden the commerce of these products.

Xenobiotics, including herbicides and fungicides, veterinary medicines, and other phytotoxic compounds, are taken up by plant roots from the soil and translocated to the shoots. This suggests that nicotine might also be acquired from the soil by agriculturally important plants. In support of this hypothesis, demonstrated nicotine uptake from soil using peppermint plants (Mentha × piperita), suggesting an uptake from nicotine-contaminated soils due to discarded cigarette butts. Subsequently, this pathway has been supported in additional studies with basil (Ocimum basilicum), parsley (Petroselinum crispum), and coriander (Coriandrum sativum), which all showed a significant accumulation of nicotine applied to soil either as tobacco leaf tissue or cigarette butts. Significant accumulation of nicotine was observed in acceptor plants even when the cigarette butt concentrations were as low as one per square meter.

Nicotine may also cycle through the plant and soil system via horizontal transfer of nicotine from donor plants to acceptor plants. This could occur directly between two living plants, or indirectly via the decomposition of acceptor plant tissues deposited in soil during plant tissue senescence or from discarded nicotine-containing products such as cigarette butts. Transfers of nicotine between living plants is presumed to be primarily from root exudation by the donor plant and subsequent uptake of nicotine by the acceptor plant growing nearby; however, the potential importance of nicotine transfer between plants via shared mycorrhizal networks has not been studied. In addition to the direct effects of nicotine on reducing plant herbivory and pathogenicity on plants, release of nicotine into the soil from root exudation or during plant litter decomposition can improve plant survival and growth of the donor plant. This benefit to donor plants appears to result from nicotine increasing the availability of several plant nutrients in the soil. With regards to aquatic ecosystems, Oropesa et al. reported that nicotine was not acutely toxic to the freshwater unicellular green algae Pseudokirchneriella subcapitata, but it did inhibit growth at concentrations of 100–200 µg/L.

Several studies have documented the effects of cigarette butts in soil and cigarette smoke on plant processes. Montalvão et al. found that the smoked cigarette butt leachate had cytotoxic, genotoxic, and mutagenic effects on onion (Allium cepa) roots at environmental concentrations (1.9 μg/L of nicotine). Discarded cigarette butts reduced the germination success and shoot length after 21 days of both perennial ryegrass (Lolium perenne) and white clover (Trifolium repens). These researchers suggested that their study demonstrates the potential for littered cigarette butts to reduce the net primary productivity of terrestrial plants while da Silveira Fleck et al. reported elevated levels of metals in plants (Eugenia uniflora and Tradescantia pallida) near a designated outdoor smoking area, suggesting that second-hand smoke can result in the contamination of nearby flora. Noble found a universal decrease in the germination rate of radish (Raphanus raphanistrum subsp. Sativus), kale (Brassica oleracea), lettuce (Lactuca sativa L.), amaranth (Amaranthus spp.), wheat (Triticum spp.), rice (Oryza spp.), barley (Hordeum vulgare L.), and rye (Secale cereale L.) seeds when exposed to tobacco smoke. This negative response was not due to the presence of nicotine in the smoke, but rather to other non-volatile components. In contrast, Tileklioğlu et al. reported that tobacco smoke increased the biomass of wheat and duckweed (Lemna minor L.) plants, and Mondal et al. found relatively little effect of tobacco smoke on the germination rate of Bengal gram (Cicer arietinum L.). Metal accumulation in plants is a common phenomenon and can affect humans indirectly by lowering plant nutritional value and directly through consumption of contaminated crops, even at low levels via chronic exposure. We found no studies that conclusively linked tobacco-related pollution with the elevated levels of metals in plants.

Non-mammalian animals

Much of the limited research on the impacts of tobacco-product waste on animals is related to cigarette butts in the environment. A study by Venugopal et al. measured a range of compounds, including nicotine, polycyclic aromatic hydrocarbons, metals, phthalates, and volatile organic compounds known to be very toxic to aquatic organisms, in leachate from field-collected cigarette butts. Another study showed that leachate from field-collected cigarette butts in the marine environment impaired copepod reproduction (Notokra sp) at low butt concentrations. Dobaradaran et al. reviewed the toxicity of cigarette butts to aquatic organisms and showed that cigarette butt leachate is toxic to a wide range of aquatic animals, including freshwater zooplankton, sea snails, frogs, frog embryos, and marine and freshwater fish. In one study, Slaughter et al. assessed the toxicity of cigarette butt leachate to fish. They reported leachate from smoked cigarette butts, which include the smoked filter plus remnants of tobacco, to be acutely toxic to both the saltwater topsmelt (Atherinops affinis) and the freshwater fathead minnow (Pimephales promelas). The lethal concentration at which 50% of the test individuals died (i.e., LC50) of approximately one cigarette butt per liter of water was observed for both species.

Non-lethal but observable negative effects, mainly immobilization, were found at lower leachate cigarette butt concentrations. There is further evidence in the literature of sub-lethal impacts to animals from tobacco-related pollutants, such as developmental, physiological, or chronic changes in behavior, that may result in fitness loss with subsequent impacts to populations. Belzagui et al. showed that microfibers from degraded cigarette butts enhanced the toxicity of cigarette butt leachate to freshwater zooplankton (Daphnia magna) in experimental 48 h toxicity tests, suggesting that the microfibers pose an intrinsic risk to small aquatic animals. In another study, Green et al. compared the toxicity of leachate from conventional plastic cellulose acetate cigarette butts and cellulose cigarette butts, which are being promoted as a biodegradable and environmentally safe alternatives. Both smoked butt types exhibited toxicity to, and decreased activity in, freshwater snails (Bithynia tentaculate). A subsequent study showed that smoked cellulose acetate cigarette butts increased clearance rates in marine blue mussels (Mytilus edulis), while cellulose cigarette butts did not.

Several theses have reported the bioaccumulation of cigarette butt pollutants in aquatic animals and potential chronic impacts on growth and behavior. Yabes found rainbow trout (Oncorhynchus mykiss) exposed to non-lethal cigarette butt leachate at a concentration of 0.5 cigarette butt/L for 28 days bioaccumulated a range of contaminants including nicotine, nicotyrine, myosmine and 2,2’-bipyridine. In addition, Yabes documented a reduced weight of fish exposed to the cigarette butt leachate compared to controls. Metals did not accumulate under similar conditions with the same organism. Filter feeding organisms that process high volumes of water like bivalves are susceptible to the bioaccumulation of pollutants. Wei found 22 compounds in cigarette butt leachate also present in an exposed marine mussel (Mytilus galloprovincialis), some of which are potentially toxic if consumed by humans or wildlife. No research has been reported on the trophic transfer of cigarette butt pollutants, a phenomenon in which the effects of toxins to wildlife are mostly noticeable in top predators as the toxin accumulates through the aquatic food web as the predators consume prey.

In one of the few studies to assess the impacts of cigarette butts in situ, Suárez-Rodríguez et al. found that ectoparasite counts decreased with increasing cellulose fiber weight in the nests of urban house sparrows (Passer domesticus) and house finches (Carpodacus mexicanus). The authors hypothesized that the observation was the result of cigarette butt-associated nicotine, a long-known pesticide. Decreased parasite load is a known fitness advantage to numerous wildlife, and further study revealed that hatching and fledging success increased with nest composition incorporating cigarette butt litter; however, blood samples from nesting birds also showed an increasing risk of genetic mutation and cancer (i.e., genotoxicity), leading to speculation that any fitness advantage from a reduced parasite load may be nullified.

Mammalian animals

Little is known about the environmental toxicity of tobacco in mammalian wildlife; however, tobacco has long been known to be lethal to various mammals, and nicotine has been used in rodenticides. In vivo laboratory studies of nicotine toxicity have been conducted in a variety of mammalian species, particularly rats and mice, and demonstrated a wide range of effects, including acute toxicity, cell mutation, reproductive effects, and behavior changes. Because rodents are an important part of the food chain in many environments, findings from animal models give some indication of the potential effects of exposure in the wild. In rats, the lethal dose of nicotine at which 50% of the test animals die (i.e., LD50) is 50 mg/kg weight, and in mice 3.3 mg/kg. One study showed that nicotine hydrogen tartrate administered ad libitum in drinking water to rats (52 ppm nicotine) and mice (514 ppm nicotine) for four weeks induced increased urinary tract cell proliferation (urothelial hyperplasia). Prenatal exposure of mice to nicotine in vivo induces underdeveloped or involuted thymus (thymic hypoplasia), impairing the immune systems of offspring through adulthood. Cotinine, the major metabolite of nicotine, administered ad libitum in drinking water to rats can induce cell proliferation and hyperplasia in rat urinary bladder and renal tissues, albeit to a lesser degree than nicotine. Mice exposed to e-cigarette aerosol have been shown to develop lung adenocarcinoma and bladder urothelial hyperplasia, lesions that are extremely rare in control mice. Exposure to e-cigarette aerosol also damages mouse DNA and impairs DNA repair activity in mouse lung tissues. Plastic cigarette butts made of minimally degradable cellulose acetate also pose a threat to animals via inadvertent cigarette butt consumption, which may lead to vomiting and neurological toxicity.

Humans

Some studies suggest that environmental contamination from cigarette and e-cigarette use, and disposal may affect human health. One 2015 study measured nicotine and tobacco-specific nitrosamines in urban outdoor air at concentrations exceeding public health standards. Other studies have discovered nicotine and particulate matter derived from tobacco smoke in urban outdoor air as potential human toxins. Passive exposure from e-cigarettes has been detected via tobacco-specific nitrosamines in the urine of non-users, but human health effects of e-cigarette aerosols remain under-evaluated. Accidental ingestion of cigarette butts is most acutely hazardous due to the nicotine poisoning risk, especially among children. E-liquids from e-cigarette devices can also be mistaken for other ingestible items and misused.

Several studies have found tobacco contaminants in key environmental compartments, including water, soil, dust, and plants. There is evidence that drinking water could be a significant exposure route. In a comprehensive study of untreated drinking water sources in the US, Focazio detected cotinine in half of the potable water samples studied. A broad survey of potable tap water samples from cities in Europe, Japan, and Latin American reported mean (maximum) nicotine and cotinine concentrations of 18 ng/L (305 ng/L) and 2 ng/L (14 ng/L), respectively. González Alonso discovered nicotine in bottled spring waters in Spain. As noted earlier, nicotine has also been detected in a variety of food crops and plant-derived commodities, and presents an additional possible source for human exposure. Other contaminants and particles that are leached into the environment from cigarettes and e-cigarette components (e.g., metals, polycyclic aromatic hydrocarbons, tobacco-specific nitrosamines and plastic nanoparticles) may bioaccumulate in plants and animals and pose additional exposure risks to humans consuming them , but there is no definitive health research on this topic.

A limited number of recent studies, as of 2021, using mice and human cell-based assays suggest that tobacco waste pollution is toxic to humans, though the potential pathways of exposure to tested pollutants is not obvious. Bekele and Ashall reported negative developmental effects in mice that ingested cigarette butt leachate, including reduced weight gain and lower organ mass. Begum et al. reported a range of neurotoxicological affects in human embryonic stem cells exposed to aqueous cigarette tar extract derived from cigarette butts. Xu et al. used a battery of in vitro human cell-based assays to assess the toxicity and biological activities of cigarette butt leachate. They noted significant impacts on key biological pathways, such as aryl hydrocarbon receptor (AhR), estrogen receptor (ER), and p53 response pathways, and identified specific compounds, including 2-methylindole, most responsible for the AhR response.

Economic impacts of contamination

While health care costs associated with tobacco use have been estimated, there is a significant gap in the literature regarding the costs related to the environmental impacts of combustible cigarette and e-cigarette use and disposal. Of particular concern is the cellulose acetate cigarette filter in cigarette butts, a form of plastic which, as noted earlier, exhibits limited biodegradability and sheds microplastic into the environment. This economic burden may be significant given the scope of the cigarette butt waste problem, especially given that people generally do not know that cigarette butts are plastic, and that casual disposal of cigarette butts is a normative component of smoking. Many cigarette butts smoked in public are littered to the urban environment rather than disposed of in proper receptacles. Adding to the burden of cigarette butts is the waste associated with the growing use of e-cigarettes. In the US, schools must now manage confiscated e-cigarettes and e-cigarette litter as hazardous waste, likely incurring significant costs associated with their collection, storage, and disposal.

The cleanup and disposal of tobacco product waste, much of it related to cigarette use, is a negative economic externality, which can be defined as a harmful effect to a third party not directly involved in the transaction and for which they are not compensated. This externality is borne by non-smokers, taxpayers, communities, and voluntary groups that conduct cleanups. The tobacco industry has supported a “blame-the-victim approach” by calling mainly for smoker responsibility and enforcement of litter regulation, as opposed to preventive policies such as the elimination of plastic filters from cigarettes. Cities incur significant cleanup and disposal annual costs for public areas, ranging on the order of USD 4 million for Portland and Las Vegas, USD 22 million for San Francisco, and USD 80 million for New York City.

In addition to the direct impacts associated with litter cleanup, there is a range of indirect impacts that need evaluation in more detail. Cigarette waste degrades environmental quality by fouling beach environments, despoiling public lands such as parks, and degrading neighborhoods and public spaces. Such indirect environmental impacts may translate to significant economic consequences due to a reduced delivery of ecosystem services such as food supply, regulating services such as water and waste purification, and cultural and aesthetic services including tourism and recreation. Single-use plastic pollution related to the littering of cellulose acetate cigarette butts, e-cigarettes, or plastic lighters also likely has a significant environmental footprint. Plastic pollution substantially impacts the delivery of ecosystem services, especially those in marine environments. Increased building fire and wildfire risk due to improper cigarette butt disposal causes an estimated 130,000 fires in the US annually, resulting in over USD 2 billion in costs associated with firefighting and USD 6 billion in property damage.

Electronic cigarette environmental concerns

Usage

Puff Bar product waste.

Puff Bar product waste

In addition to environmental harms from production, understanding the potential environmental impact of the use of e-cigarettes is important. Beside the direct harm experienced by users, e-cigarette vapors are potent sources of air pollution such as aldehydes, carbon monoxide, particulate matter, VOCs, heavy metals, and nicotine. Compared to smoke from conventional cigarettes, the amount of particulate matter and heavy metal emissions from e-cigarette vapor were found to be similar or greater.

The use of e-cigarettes has grown in popularity worldwide. E-cigarettes are highly popular among youth and young adults. Consumption and sales of e-cigarettes have risen dramatically worldwide. Sixty million e-cigarettes and refills are sold annually, and one-third of these are designed for single-use in the US. The global market value was estimated to grow from US$ 14.53 billion in 2017 to US$ 48.9 billion by 2025. In the year ending January 2023, there were 543,000 vapers in Scotland - of which 51,000 (9%) were under 16 and 78,000 (14%) were under 18. Most under 18 e-cigarette users in Scotland prefer single-use vapes.

The rise of e-cigarettes in industrialized countries is changing the composition of the environmental harms of tobacco. Because these products are composed of low-value but sophisticated electronics, the environmental costs from manufacturing e-cigarettes may be substantially more severe than cigarettes per unit.

Limited research

Evidence remains limited regarding the environmental impacts of e-cigarettes. Furthermore, no studies have formally evaluated the environmental impacts of the life cycle of e-cigarettes. Although information exists about the direct impact of e-cigarettes on health, very little scientific evidence exists concerning the environmental impact of the life cycle of these products and their potential indirect health harm.

Despite the emphasis on the environmental threat of e-cigarettes, there are limited scientific studies on the environmental impacts of the e-cigarette life cycle (manufacturing, use, and disposal). This life cycle is not studied enough for its impacts on human health associated with environmental pollution. As a result, critical ecosystems providing clean water, air, and food production, can be negatively affected.

Although limited data have been reported about the life cycle of e-cigarettes, they may represent a significant long-term environmental threat due to the toxic nature of their composition. It is also unclear how the environmental impacts of e-cigarettes compare to those of conventional cigarettes. For instance, it could be informative to compare the life cycle pollution from production to disposal between traditional cigarettes and e-cigarettes.

Public health implications

The impact of e-cigarettes on public health includes a range of consequences for the environment, such as air quality effects, energy and materials used, issues related to environmentally responsible disposal and land-use decisions. From their manufacturing, use, and disposal, the environmental impacts of e-cigarettes present a novel public health concern. An example is that e-cigarettes are a growing waste management concern because, despite their small size, they are consumed and discarded much more quickly than typical electronics.

Emerging threat

As of 2017, Ibis World, an industry market research company, predicts that "the [traditional] Cigarette and Tobacco Product Manufacturing industry is in the declining stage of its life cycle". They note, however, that the industry will resist this decline through expansion into e-cigarettes and other electronic nicotine delivery devices.

The tobacco industry is aware of the new scope of environmental harms e-cigarettes pose. PMI in 2016 discussed the "need to manage new areas of impact due to the increasing use of electronics and batteries in our products". As tobacco companies increasingly are selling electronic smoking devices, they acknowledge that "while we embed new processes, the efficiency of our energy and water use may worsen until both knowledge and economies of scale improve". PMI's Lifecycle Analysis performed for e-cigarettes and other so-called reduced-risk products (RRPs) "highlighted the impact that RRPs will have in [their ecological] footprint and plans in product development, manufacturing, distribution and rest of value chain have been implemented to mitigate their impact in our footprint".

Tobacco industry environmental claims

Despite the absence of supporting data or environmental impact studies, eco-friendly claims have been used by manufacturers as a marketing strategy to promote e-cigarettes to consumers.

Since e-cigarettes are mainly owned by the tobacco industry, it is important to question whether vaping is more eco-friendly than smoking, as companies claim. Tobacco companies, including e-cigarette industries, recognize that they need to address novel environmental impacts caused by their growing use of batteries and other electronics in e-cigarettes. Yet, despite recognition of the potential hazards, eco-friendly claims are often used as a marketing strategy by the tobacco industry. If these claims are shown to be false, then 'greenwashing' needs to be called out to avoid misinformation being used as a tool to unethically drive consumer demand.

Contradictory and confusing information exists concerning public health risks and benefits of e-cigarettes. For example, their growing popularity can partly be attributed to e-cigarettes being marketed to the public as 'healthier alternatives' and 'eco-friendly' compared to conventional cigarettes. However, several scientific studies suggest that e-cigarettes may have short- and long-term health effects.

Production

In regard to production, it is worth noting that e-cigarettes contain a battery, a heating element, an atomizer (aerosolization chamber), a cartridge, an e-liquid, and a mouthpiece. Manufacturing the product is an energy-consuming process with associated environmental impacts. For example, extraction and purification of nicotine from the tobacco plant requires a large amount of water and generates non-recyclable halogenated waste and pollution. Also, as a result of e-cigarette marketing, the demand for tobacco crops could potentially increase, which would present a potential alteration in land use.

Greater e-cigarette production demand drives increased pollution (e.g. greenhouse gas emissions), therefore contributing to processes that may lead to climate change. Due to a lack of regulations in countries like the US, data on pollutant contamination of water, land, and air may not be obtained from manufacturing sites11. However, global environmental impacts are important to consider because ingredients and components of e-cigarettes are manufactured and imported from low- and middle-income countries including India.

Manufacturing standards

E-cigarettes made in different countries are manufactured according to the standards of the manufacturer's country, and do not always conform to laws for exposures to metals and other toxicants in the countries they are used. E-cigarette manufacturers across the world have made minimal effort to make their products recyclable and to prevent valuable resources from winding up in landfills.

Components and materials

The chemical content of e-liquids and the construction of e-cigarettes vary widely—from disposable single-use "cig-a-like" products resembling cigarettes, to refillable "vape pens," to "mods" and "tanks." The best-selling device in the US in 2018 was the Juul cartridge-based or "pod" e-cigarette. While the USB stick-shaped device is not single-use, its hard plastic e-juice cartridges are. Because of the overwhelming diversity of products, no blanket assertion on the environmental impact of these products is possible. Introducing new classes of plastics, metals, cartridges, lithium-ion batteries, and concentrated nicotine solutions, however, involves significantly more environmentally intensive manufacturing processes than products that are primarily made of plant material and plastic filters, as combustible cigarettes are.

Each disposal e-cigarette device contains roughly 0.15 grams of lithium within its battery, which is a metal that both the US and EU designate as an essential raw material. Greater than 90 tonnes of lithium were estimated to have been utilized in the manufacturing of disposal e-cigarette devices, which collectively generated $5 billion in global sales in 2022. They also utilized approximately 1,160 tonnes of copper in the same period. In 2022, the e-cigarette devices sold in the UK were made with enough copper to manufacture 370,000 at-home electric vehicle chargers and used enough lithium to create more than 2,500 EV batteries.

Carbon footprint

The environmental impact of single use vapes include their greenhouse gas emissions. Total emissions associated with disposable vapes in 2022 in Scotland were estimated to have been up to 4,292 tonnes CO₂e – the equivalent of around 2,100 cars on Scotland's roads.

Tobacco industry recycling challenges

Fundamentally, the tobacco industry has been aware of "cradle to grave" extended-producer responsibility manufacturing since at least as early as 1991, and has nonetheless refrained from implementing practices that could reduce the waste from their products, both in terms of production and disposal. Conventional cigarette filters, for instance, have been proven to do more harm than good in terms of health, and these unnecessary appendages to cigarettes, originally developed in the 1950's to assuage growing fears over the health harms of cigarettes, directly harm the environment in their material production and disposal. Based on reviewing industry documents, it does not appear as if any cradle-to-grave industrial ecology has been undertaken to minimize the amount of ecological impact of e-cigarette manufacturing and disposal.

Consumer recycling challenges

Increased use of e-cigarettes has led to a rise in the release of e-cigarette waste and related contaminants into the environment. E-cigarette emissions and waste contain measurable amounts of nicotine and other toxic chemicals, thereby serving as significant sources of environmental pollution. E-cigarettes that are thrown away that end up in landfills is a rising public health concern. Up to 26 million disposable vapes were consumed and thrown away in Scotland in the last year leading up to June 2023, of which an estimated 10% were littered and more than half were incorrectly disposed of, according to a 2023 Scottish Government report. Each week, more than 1.3 million disposable vaping devices are thrown away in the UK. According to recent findings by the Green Wings Project, as of 2023, 75% of UK users acknowledge they do not participate in recycling their used e-cigarette devices. Most of these devices are not likely to be recycled.

Some e-cigarettes are designed to be completely disposable, while others are rechargeable. Disposable e-cigarettes and vaping pods, spent e-cigarette capsules or replaceable pods, pose the most significant potential environmental burden5. Vaping pods are an example of plastic waste because they are not biodegradable and are poorly recyclable. Also, they contain similar waste components as reusable e-cigarettes but are used for a shorter time before being discarded.

Components like batteries and replaceable capsules containing concentrated nicotine residues can leach pollutants into water, air, and soil. A particularly serious threat of environmental pollution is the littering of e-liquid containers. They may contain high concentrations of residual nicotine, of known and unknown toxicity, and flavoring additives such as aldehydes.

Therefore, e-cigarettes have different types of waste, including biohazard, plastic, and electronic waste. We contend that the potential waste load from e-cigarettes exceeds that of traditional cigarettes due to the larger amount of components. E-cigarette components like nicotine, lithium-ion batteries, and electronic circuit boards, are considerable forms of biohazard and electronic waste. On the one hand, the biohazard waste (nicotine, lithium-ion batteries) risk arises when e-cigarettes are improperly discarded and when broken components leach heavy metals (e.g. mercury, lead) and release toxic chemicals into the environment, affecting humans and animals. These products can then bioaccumulate in animals and humans, creating health issues. Discarded components like batteries pose a risk of explosion and a risk of fire hazard in waste and recycling facilities.

The Basel, Rotterdam, and Stockholm conventions are science-based, legally binding global treaties aimed at protecting human health and the environment from hazardous chemicals and wastes. However, non-compliance is common as the global transport of waste continues to expand. Most e-waste from Western countries is shipped to developing countries, shifting the dangers and pollution-related risks to settings that are often least able to adequately address and mitigate them. This rich-to-poor country shift transfers risk and harm whilst further exacerbating global health inequities.

Recycling initiatives

The waste management company Veolia has started a vape recycling and collection service in the UK in 2023 for retailers.

Regulatory oversight

In the US, e-cigarettes originally were to be included as drug-delivery devices under the US Food and Drug Administration, which would have required much stricter product regulation. However, a 2010 suit overturned this designation. The 2016 US FDA Deeming Rule aimed to place e-cigarettes under a 2007 regulatory cut-off which would require extensive testing of e-cigarettes if they wished to remain on the market. As the deadline for this requirement has been postponed from 2018 to 2022, e-cigarette manufactures are free to produce and sell devices with minimal oversight by health or environmental regulatory institutions.

In the UK, while e-cigarettes disposal and reclamation must adhere to the Waste Electrical and Electronic Equipment Regulations, requiring companies to receive and process electronic waste, the arduous process of sending these products back to manufactures and having to pack and pay for postage to responsibly return these products likely limits the effectiveness of such consumer-side responsibility to unknown efficacy.

Proposed regulatory initiatives

A 2023 review states that biohazard and electronic waste should not be discarded in regular trash and instead should be disposed of in specific facilities. E-cigarette environmental impacts can be prevented with improved regulation of their production, use, and disposal. For example, the gradual elimination of disposable e-cigarettes in favor of reusable e-cigarettes and proper recycling and waste management could reduce environmental damage.

Positions of professional organizations

Lorna Slater, Minister for Green Skills, Circular Economy and Biodiversity said in 2023: "that single use vapes have become a big problem - for our environment, local communities and young people. I will take action and will engage with those affected, including young people, over the coming months, with a view to setting out a way forward in the Autumn."

Iain Gulland, Chief Executive, Zero Waste Scotland said in 2023: "Any form of littering is unacceptable – it damages the environment, economy, and is a blight on the areas where we live, work, and socialise. Single use vapes are made up of components which, unless disposed of safely and responsibly, can last on our planet for years and years. And the sight of them, discarded on our streets, is becoming far too common."

Proposed ban on disposable e-cigarettes

In 2023, the Royal College of Paediatrics and Child Health in the UK insisted on a ban on non-reusable vape products. They stated they "are not a risk-free product and can be just as addictive, if not more so than traditional cigarettes". They also stated that the "serious environmental impact of disposable e-cigarettes" should not be disregarded.

Councils in England and Wales are pushing for a 2024 ban on single use vapes due to environmental and health risks, as 1.3 million are thrown away weekly. Recycling challenges, waste issues, and fire hazards are cited. Concerns about youth vaping are also raised. The UK Vaping Industry Association defends disposables as quitting aids but warns of potential black market products if banned.

Environmental contamination assessment

Environmental contamination from e-cigarette use and disposal is less well documented and requires more attention, especially given the growing popularity of these products. Pollution sources include discarded e-liquid pods and their contents, other e-cigarette components that include batteries and other metallic components, and entire single-use, e-cigarette systems. The market for these products may grow dramatically given recent actions of the US Food and Drug Administration to approve them as reduced exposure tobacco products and widespread global marketing by tobacco companies, as of 2021.

Because of the ubiquitous disposal of used e-cigarettes (and cigarettes), several waste management systems may be sources of tobacco pollutants to the environment. These include the effluents of treated domestic wastewater, leachate seeping out of landfills, and discharges from urban storm drains and because there may be non-tobacco sources of nicotine, it is sometimes difficult to link nicotine pollution to tobacco use, especially for landfills. Nicotine and the cotinine metabolite have been extensively detected in a variety of surface waters, and to a lesser extent in ground waters. Of particular concern, is the assessment of the continuous releases of low-concentration tobacco pollutants from wastewater and stormwater discharges, which have the potential for chronic toxicological effects on aquatic biota and possibly human health.

To support effective policies to reduce the negative economic externalities of e-cigarette pollution, a more comprehensive picture of direct and indirect environmental costs of e-cigarette use and disposal is needed. The estimation of scientifically defensible environmental costs, coupled with more extensive studies of the sources and impacts of these environmental pollutants, could encourage policy changes that limit environmental damages, while also shifting responsibility for these damages away from the public and upstream to tobacco product producers, suppliers, and retailers.

See also

• Human impact on the environment
• Environmental impact of tobacco

Further reading

• "A toxic, plastic problem: E-cigarette waste and the environment". Truth Initiative. 8 March 2021.
• Ducharme, Jamie (11 July 2023). "The Overlooked Environmental Impact of Vaping". Time.
• Perrone, Matthe (19 October 2023). "Communities can't recycle or trash disposable e-cigarettes. So what happens to them?". AP News.