Electronic nicotine delivery systems (ENDS) are battery-powered devices that deliver aerosol vapor, known to include propylene glycol, which decomposes into formaldehyde and other carcinogens. The safety of ENDS and their efficacy in smoking cessation programs have not been demonstrated, and scientific evidence exists to the contrary. In the United States, ENDS use has increased among all demographic groups, including young people, vulnerable populations, and minorities. Studies suggest that ENDS use increases use of combustible tobacco, and chemicals are harmful to both users and those exposed to secondhand vapor. In August 2016, the U.S. Food and Drug Administration (FDA) “deeming regulations” established that ENDS could not be sold to anyone under 18 years of age or via vending machines (unless sold within an adult-only facility). On September 12, 2018, the FDA announced that it had issued or levied more than 1,300 warnings and civil penalties to tobacco retailers that illegally sold JUUL (a popular brand of ENDS) and other ENDS to minors. This was the strongest policy enforcement by the FDA since the deeming regulations were enacted. As of July 2018, 13 states, Puerto Rico, the District of Columbia, and more than 100 cities included ENDS in their smoke-free air policies, and several corporations prohibit the use of ENDS in workplaces. APHA supports efforts to regulate ENDS, urges restriction of ENDS advertising and promotion, encourages prohibition of ENDS use in public places and workplaces, calls for evidence-based research regarding ENDS efficacy in smoking cessation, and recommends prohibiting the sale of ENDS to people 21 years and younger.
Relationship to Existing APHA Policy Statements
An update to Policy Statement 20149 (Supporting Regulation of Electronic Cigarettes) was identified as an APHA policy gap for 2018. Relevant policy statements other than 20149 include the following:
- APHA Policy Statement 201710: Protecting Children’s Environmental Health: A Comprehensive Framework
- APHA Policy Statement 20082: Discouraging Smoking in Feature Films to Avoid Influencing Youth to Smoke
- APHA Policy Statement 20076: Tobacco-Free School Environments
- APHA Policy Statement 9514: Reducing Youth Tobacco Use through Increased Excise Taxes
- APHA Policy Statement 9412: Regulation of Tobacco Products by the Food and Drug Administration
- APHA Policy Statement 9302: Tobacco-Free Schools
- APHA Policy Statement 9301: Environmental Tobacco Smoke
- APHA Policy Statement 9213: Advertising and Promotion of Alcohol and Tobacco Products to Youth
- APHA Policy Statement 8710: Smoke-Free Indoor Air
- APHA Policy Statement 8604: Taxation of Tobacco Products
- APHA Policy Statement 8605: Advertising and Promotion of Tobacco Products
- APHA Policy Statement 8507: Health Risks and Advertising of Smokeless Tobacco Products
- APHA Policy Statement 8318: Toward a Smoking-Free Society in the United States by the Year 2000
- APHA Policy Statement 8008: Fire Safe Cigarettes
- APHA Policy Statement 7225: Small Cigars
- APHA Policy Statement 6301: Cigarette Smoking and Health
Electronic nicotine delivery systems (ENDS) include any devices used to deliver aerosolized or vaporized nicotine (e.g., e-cigarettes, e-cigars, e-pipes, vape pens, and hookahs) as well as the components, parts, or accessories of such devices. ENDS do not include drugs, products, or combination products authorized for sale by the U.S. Food and Drug Administration (FDA), which are defined in the federal Food, Drug and Cosmetic Act of 1938. The e-cigarette was invented in China in 2003 and introduced in the United States in the mid-2000s. There is conclusive evidence that e-cigarette use has been increasing in all population subgroups and across geographic areas of the United States.[3–7] An analysis of 2011–2017 National Youth Tobacco Survey (NYTS) data showed that e-cigarettes were the most commonly used tobacco products among high school (11.7%) and middle school (3.3%) students in 2017. According to 2011–2014 NYTS data, 13.5% of middle school students and 37.7% of high school students had used e-cigarettes. Initiation of e-cigarette use increased rapidly between 2013 and 2015, peaking in 2015, when one out of five students reported having used e-cigarettes in the preceding 30 days. Among adults 18 years and older, analyses of 2015 National Health Interview Survey data showed that the prevalence of e-cigarette use in the preceding 30 days was 3.5%; 12.6% reported using e-cigarettes during 2014. In the 2014–2015 Tobacco Use Supplement to the Current Population Survey, the prevalence of current e-cigarette use ranged from 1.3% in Delaware to 4.4% in Wyoming. This initiation of ENDS use in the United States amid uncertainties poses public health challenges.
In 2016, the Food, Drug and Cosmetic Act was amended through the Family Smoking Prevention and Tobacco Control Act to give the FDA the authority to regulate tobacco products, including ENDS. Unlike conventional combustible tobacco, ENDS do not generate side-stream vapor (aerosol between puffs), and there is increasing evidence that ENDS contain fewer toxic elements.[1,12] Simultaneously, there is growing evidence that exposure to exhaled vape has deleterious health effects on non–ENDS users, including children.[1,3,12–14] According to the World Health Organization (WHO); the National Academies of Sciences, Engineering, and Medicine6; and the scientific literature,[15,16] evidence for the safety of ENDS and their efficacy in smoking cessation programs is not conclusive. Studies focusing on the biochemical constituents, physiological and psychological effects, and health risks or benefits of ENDS vary in terms of their methodological rigor, sample sizes, recruitment techniques, and controls for potential confounding variables.
In spite of uncertainties about the efficacy of ENDS in smoking cessation and safety concerns,[12,17] many ENDS manufacturers promote their products as healthier alternatives to conventional combustible tobacco and market them as a method to cease smoking conventional tobacco.[12,18,19] Thus, a harm reduction orientation that considers the net costs and benefits relative to conventional tobacco smoking has been adopted and promoted by the industry. Recognizing the global burden of tobacco-related morbidity and mortality (approximately 7 million deaths annually), some scientists have adopted this harm reduction approach.[21,22] However, to date, the proposed public health value of ENDS is not supported by evidence of their therapeutic benefits in terms of smoking cessation.[3,13] The harm reduction approach does not take into consideration the harmful effects of nicotine, particularly on vulnerable populations (e.g., an unborn fetus or individuals exposed to secondhand[1,23] and thirdhand aerosol vapor). Evidence indicates that prenatal exposure to nicotine can result in developmental abnormalities in the brain and lungs[3,25] and is the most common risk factor for sudden infant death syndrome. Relatedly, some studies show that pregnant women who believe ENDS to be less harmful than conventional cigarettes may be more likely to switch from cigarettes to ENDS during their pregnancy.[3,27] One study reported that, among a sample of pregnant women, 43% believed that using ENDS was less harmful to their fetus than using conventional cigarettes, and three quarters of those who used ENDS claimed this as their reason for switching from cigarettes to ENDS. As such, more behavioral and clinical research is needed to better understand and address this major gap in knowledge about ENDS.
Public health in the United States, however, faces several challenges with this increasing trend of ENDS use. There is a high level of awareness of ENDS among middle and high school students,[29,30] with a systematic review reporting that nearly all adolescents are aware of e-cigarettes. In addition, there is an emerging literature indicating that ENDS use is associated with a greater risk of using conventional tobacco.[3,30] Youths who may otherwise not smoke any combustible tobacco start to use ENDS and progress to regular smoking.[30–34] The increasing trend of ENDS use has the potential to create a new generation of youths addicted to nicotine, which threatens to undermine the public health gains of the past half century by renormalizing smoking[3,13] through social environments that promote cigarette use. Moreover, rates of ENDS use among vulnerable populations, including those living with a mental illness[36,37] and minority populations,[38,39] have increased. A study conducted by Forman-Hoffman et al. revealed that people living with psychiatric disorders are responsible for 56.4% of the cigarettes consumed in the United States. This group has been disproportionately affected by smoking, with approximately 50% of deaths among mental health patients attributed to tobacco-related illnesses. Simultaneously, emerging studies suggest that U.S. adults living with psychological distress are susceptible to using e-cigarettes[42,43]; according to one study, mental health patients who were former smokers were six times more likely to be interested in using e-cigarettes than those without mental illness.
Another study showed that e-cigarette use is significantly higher among Vietnamese and Filipino Americans (classified as Native Hawaiians and Pacific Islanders) than among Chinese Americans (classified as Asian Americans). This study also revealed that e-cigarette use in these populations is higher among men, those with low risk perceptions of ENDS, and those with lower educational attainment. The increasing rates of ENDS use among youths and vulnerable populations extend ethics, social justice, and social relations issues and demand the attention of the public health community.[44–46] Consequently, the parties to the WHO Framework Convention on Tobacco Control, the international tobacco control treaty developed under the auspices of WHO, have been urged to regulate ENDS within the current tobacco control framework, including prohibition or restriction of promotional materials, advertising, and sponsorships. Similarly, several health-related organizations recommend that ENDS be defined and regulated as tobacco products.
Evidence-Based Strategies to Address the Problem
Proposals for addressing the proliferation of ENDS use emanate from policy research conducted by the U.S. Centers for Disease Control and Prevention (CDC), the U.S. surgeon general,[3,13] and WHO, along with research published in the scientific literature.[12,48–50] In their study, Pesko et al. found that raising prices, restricting flavoring, and adding warning labels were associated with reduced ENDS use. Similarly, Huang et al. concluded in their study that increasing e-cigarette retail prices (e.g., by imposing a tax on e-cigarettes) could lead to significant reductions in sales. They also concluded that increased taxes will discourage adult smokers from switching to ENDS. Detailed policies that APHA supports are outlined in the sections to follow.
Prohibit secondhand exposure to ENDS vapor: ENDS vapor contains toxins, and exposure to secondhand aerosol has adverse health effects.[1,3,51,52] Although ENDS do not generate side-stream aerosols between puffs, users do release aerosols upon exhalation. Laboratory smoking chamber studies comparing secondhand exposure to ENDS aerosols with exposure to conventional cigarette smoke have shown that nicotine and probable carcinogens are released in ENDS aerosols but at lower levels than those associated with cigarettes.[1,3,52] However, other studies have documented particle size distributions similar to those of conventional tobacco cigarettes, with some e-cigarettes delivering more particles than conventional cigarettes. One study reported that the flavoring chemical diacetyl (a known cause of “popcorn lung,” a severe respiratory disease) was measured in 39 of 51 e-cigarettes tested. It has been concluded in reviews of research on ENDS that ENDS aerosol is not merely “water vapor” as is often claimed in the marketing of these products.[18,52] As such, ENDS nonusers should be protected from exposure to vapor by expanding coverage of smoke-free policies to include ENDS.
Protect children and youths from exposure to e-liquids: Exposure to nicotine liquids is a public health hazard and is a particular risk for infants and young children because the nicotine solution is sold in bottles and cartridges that can lead to accidental poisoning.[1,12,52] Between January 2012 and April 2017, 8,269 children 6 years and younger were reported by U.S. poison control centers to have been exposed to liquid nicotine; more than 80% of the affected children were less than 3 years of age. Moreover, research suggests that youths are rapidly adopting ENDS that tend to contain candy flavors and that young people who use ENDS are heavier, not lighter, smokers of conventional cigarettes.[1,3,13,30] Thus, companies producing ENDS should be required to use childproof packaging and adhere to design standards that do not appeal to children and youths. In addition, flavoring of e-liquids for ENDS should be prohibited.
Conduct research on ENDS as smoking cessation devices: Studies suggest that ENDS are comparable to, but not more effective than, other means of quitting smoking of conventional tobacco cigarettes.[1,15] A report by the National Academies of Sciences, Engineering, and Medicine concluded that there is insufficient evidence from randomized con¬trolled trials about the effectiveness of ENDS as cessation aids relative to no treatment or FDA-approved smoking cessation treatments, including nicotine replacement therapies; however, results from observation studies have been mixed.[1,56] The National Academies report also indicated that there is moderate evidence from observational studies that more frequent use of ENDS is associated with an increased likelihood of cessation. These mixed results suggest the need for more research on the risks or benefits of ENDS as cessation devices, especially in comparison with conventional nicotine replacement therapies.
Restrict advertising, marketing, and promotion of ENDS: According to WHO, the estimated global ENDS market was more than $10 billion in 2015, with the United States accounting for 56% of this total. ENDS hold a competitive advantage over conventional tobacco cigarettes in terms of advertising and marketing. The reason for this advantage is that the Public Health Cigarette Smoking Act of 1970, the Tobacco Master Settlement Agreement of 1998, and the Family Smoking Prevention and Tobacco Act of 2009 prohibited advertising and marketing of conventional tobacco cigarettes on television and in print media with high youth readership, as well as prohibiting cigarette manufacturers from sponsoring sporting events and music festivals. Research suggests that, as a result of a lack of regulation, advertising, marketing, and promotion of ENDS have been increasing in several venues, including direct sales to consumers and online sales, with youths as one of the target groups.[58,59] An analysis of NYTS data indicated that approximately seven in 10 U.S. middle and high school students were exposed to e-cigarette advertisements in 2014. In a review of 124 publications on ENDS marketing and communications, Collins et al. found that exposure to ENDS advertisements may be related to experimentation with ENDS among youths and young adults. Historically, manufacturers of conventional tobacco cigarettes used advertising and marketing strategies of product differentiation (e.g., offering filter tips and menthol flavors) and market segmentation (e.g., targeting youths and women). Many current ENDS advertising and marketing campaigns resemble those used over the years to promote conventional cigarettes, especially to teenagers. Therefore, restrictions on advertising, marketing, and promotion of tobacco such as those outlined in the Master Settlement Agreement should be extended to ENDS; there is a high level of support on the part of the general public for such regulations.
Investigate the possibility of setting the minimum legal sales age at 21 years: Evidence indicates that up to 90% of regular smokers initiated smoking by 18 years of age and 99% by 26 years of age. Thus, current minimum age of sales laws do not protect many of the people at risk for smoking initiation. Emerging evidence indicates that, similar to the case among youths,[1,3,30] ENDS use could lead to use of conventional tobacco products among young adults[30,62] not covered by existing minimum age of sales and youth access laws. In a study involving Hispanic young adults, Unger et al. found that among past-month cigarette nonsmokers, those who were past-month e-cigarette users in 2014 were more than three times as likely to be past-month cigarette smokers in 2015 as those who did not report past-month e-cigarette use. To address this issue, APHA recommends raising the minimum legal sales age to 21 years to prevent tobacco use initiation among this vulnerable age group. The Institute of Medicine recommended raising the minimum legal sales age of all tobacco products to 21 years based on predictive modeling showing that reductions in tobacco use initiation, particularly among adolescents 15 to 17 years old, improve the health of Americans across their life span and save lives. However, to date, there is no convincing data on the impact of raising the minimum legal sales age for ENDS to 21 years. Nevertheless, existing evidence suggests that there is increasing public support for such policies.[50,65–67] Following policy implementation, New York City saw a decline in retailer compliance with ID checks, indicating a need for ongoing education and enforcement after enactment of minimum legal sales age policies. Moreover, some states have preemption laws, which serve as a barrier to protecting youths from exposure to ENDS. Thus, although more investigation on the impact of setting the minimum legal sales age of ENDS at 21 years is needed, APHA supports protecting youths and young adults from exposure to ENDS in the same manner as for conventional tobacco products.
The scientific evidence to date suggests that current-generation ENDS products are demonstrably less harmful than combustible tobacco products in several key ways, including the fact that they generate lower levels of carcinogens and other toxic compounds than combustible tobacco products.[1,3,51,52] A study conducted for an e-cigarette advocacy group examined e-cigarette users’ exposure to propylene glycol and glycerin and calculated occupational threshold limit values to evaluate potential risks to users. The study did not report any evidence that use of e-cigarettes produces inhalable contaminants exceeding threshold limit values among users. However, according to a comprehensive appraisal of peer-reviewed published research, it is inappropriate to apply threshold limit values to exposures among coworkers and people with medical conditions. Moreover, according to this review, industry claims that e-cigarettes help smokers quit are not wholly supported by the evidence. Nevertheless, ENDS are supported as harm reduction devices by the industry and a segment of the public health community.
The strongest support for ENDS as a harm reduction device came from a group of nicotine scientists.[71,72] In 2014 and 2018, nicotine science and public policy specialists wrote the directors-general of WHO, Dr. Margaret Chan and Tedros Adham Ghebreyeus, respectively, to argue that regulation should exploit the considerable health opportunity to reduce harm from combustible tobacco products. The 2014 letter sent to Dr. Chan argued the following: (1) outcome measures, rather than focusing on nicotine use per se, should focus primarily on reducing smoking in order to decrease the prevalence of disease and premature death; (2) it is counterproductive to ban the advertising of e-cigarettes and other low-risk alternatives to smoking; (3) it is inappropriate to apply legislation designed to protect bystanders or workers from tobacco cigarette smoke to e-cigarette aerosol vapors; and (4) the tax regime for nicotine products should reflect risk and be organized to create incentives for users to switch from smoking to low-risk harm reduction products. A February 2018 report published by Public Health England reached similar conclusions. Although the American Heart Association supports regulation of ENDS and has noted that current evidence does not support use of ENDS as a primary cessation aid, it supports patients’ wish to use these devices to help them quit if (1) they did not succeed with initial cessation treatments, (2) they are warned that ENDS may contain low levels of toxic chemicals, (3) they understand that ENDS have not been proven as cessation devices, and (4) they are advised to consider setting a quit date for using ENDS as a cessation method. Thus, it has been claimed that ENDS can be effective in the fight against tobacco-related morbidity and mortality with expansion of harm reduction strategies.[1,15,72,74,75]
Some evidence exists in support of ENDS as cessation devices. A systematic review88 concluded that there is evidence from two trials that e-cigarettes help smokers stop smoking long term (relative to placebo e-cigarettes). In contrast, other studies have shown that ENDS use is associated with less quitting among smokers and can lead to symptoms of dependence on ENDS.[1,74] Therefore, the efficacy of existing tobacco cessation therapies should be considered in evaluating the therapeutic role of ENDS. Moreover, cessation research suggests that ENDS alone are not any more effective than other strategies.[1,17,76] In addition, there is no proven cessation benefit of ENDS use, and emerging evidence indicates that the link between ENDS use and cessation is not clear cut because the relationship depends on several factors, including frequency of use of ENDS, people’s smoking history and smoking status, ENDS flavoring, compensatory behaviors, and vaping topography. There is growing evidence that ENDS users do not quit at significantly higher rates than users of conventional cigarettes and that ENDS are not commonly used as a quit tool among youths and young adults; rather, they are used as a secondary source of nicotine, most commonly among current smokers. This growing evidence questions the linkage between ENDS and smoking cessation.
The benefits of ENDS as smoking cessation devices also pose ethical dilemmas with respect to product safety, efficacy for smoking cessation and reduction, use among nonsmokers and young people, marketing and advertisements, use in public places, renormalization of a smoking culture, and market ownership. In this regard, youths and young adults who perceive that ENDS are less harmful than conventional cigarettes are more likely to use them, although evidence on the safety of ENDS is inconclusive. Moreover, although some studies have shown that ENDS may facilitate smoking cessation in vulnerable groups such as those with mental illnesses, Gentry et al. concluded in a systematic review that concerns remain about the safety of the devices. In addition, exposing youths to ENDS use through advertising and promotions increases the risk of uptake among nonsmokers and subsequent transition to the use of conventional cigarettes[3,79]; this creates a major ethical problem because youths and young adults do not usually use ENDS as tobacco cessation devices. These ethical concerns (coupled with inconclusive evidence about the safety of ENDS and the fact that efforts to encourage smokers who are unable to quit to switch to a less harmful, “safer” cigarette have not been successful in the past) suggest that ENDS may not be the panacea with respect to smoking cessation, which implies the need for regulation.
Policies and programs designed to address ENDS use in the United States seem to lag behind the problem.[47,80–82] A December 2017 CDC report examined the U.S. e-cigarette policy landscape with a focus on five policies: (1) prohibition of e-cigarette use and conventional tobacco smoking indoors in restaurants, bars, and worksites; (2) requirement of a retail license to sell e-cigarettes; (3) prohibition of e-cigarette self-service displays; (4) establishment of 21 years as the minimum age to purchase all tobacco products, including e-cigarettes; and (5) application of an excise tax to e-cigarettes. This report indicated that 72 laws related to these policies were enacted in 34 states between January 2010 and September 2017; 16 states did not have any legislation related to the policies, while California had legislation in all five areas. The American Nonsmokers’ Rights Foundation reported that, as of July 2018, only 13 states and 752 localities restricted use of ENDS in 100% smoke-free venues. Thus, there is a regulatory vacuum that critically needs to be filled.
ENDS are still a comparatively new phenomenon relative to both combustible and noncombustible tobacco products, for which evidence-based policies have successfully reduced the prevalence of use by more than half over 50 years. Policy proposals from the CDC, the U.S. surgeon general,[3,13] WHO,[14,57] and policy experts[12,48,49] suggest that the following can serve as promising interventions to reduce ENDS use: (1) removing preemption to allow localities to regulate the sale, distribution, and use of ENDS and e-cigarettes; (2) creating specified distances from schools for the sale of ENDS; (3) regulating purchasing and illicit trade in ENDS across states; (4) enforcing existing ENDS regulations; (5) adopting nicotine-free workforce policies; and (6) adopting 100% tobacco-free policies that include ENDS in educational and health facilities. These policy proposals are not included in the subsequent action steps because they are inferences from policies addressing tobacco use and scientific evidence to support their use for ENDS is inadequate. Nonetheless, similar to conventional tobacco use, adopting a comprehensive approach could be the best means of halting the increasing trend of ENDS use in the United States.
Although governments at the federal, state, and local levels have regulatory authority over ENDS, the evidence[12,47,80,81] suggests that such authority is underutilized. Thus, the following action steps should be taken:
- The Consumer Product Safety Commission should add nicotine to its list of substances covered by regulations and should require special packaging, such as childproof packaging and warning labels, on nicotine solution cartridges to prevent childhood poisoning.
- Congress should amend the Prevent All Cigarette Trafficking Act to include ENDS, which would prohibit Internet venders from distributing them through the U.S. Postal Service.
- Federal agencies and voluntary health organizations should fund research on the short- and long-term health effects of ENDS on users and nonusers and the efficacy of ENDS as a harm reduction or smoking cessation strategy.
State and Local Actions
- Laws prohibiting the distribution of free samples and coupons for ENDS should be enacted and enforced, and use of ENDS should be prohibited in all enclosed areas of public access and places of employment. These standards should be incorporated into existing clean indoor air laws.
- A tax on the nicotine liquid used in e-cigarettes should be imposed, as evidence from the existing literature indicates that increased ENDS prices are associated with reduced selection and sales of ENDS.
- Employers should prohibit ENDS use on their premises.
- The ENDS minimum legal sales age should be raised to 21 years.
- Community education programs should be developed to educate youths, parents, and pregnant women regarding the dangers of nicotine exposure.
- Further research on ENDS should be conducted given that evidence on ENDS as harm reduction and smoking cessation devices is still inconclusive.[1,12]
- Illicit sale of ENDS and sales through online vendors should be prohibited because such distribution tactics make it difficult to regulate ENDS[84–86] and avoid the FDA’s deeming law.
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