18B.6Potential negative impacts

Last updated: November 2018        

Suggested citation: Greenhalgh, EM, & Scollo, MM. InDepth 18B: Electronic cigarettes (e-cigarettes). In Scollo, MM and Winstanley, MH [editors]. Tobacco in Australia: Facts and issues. Melbourne: Cancer Council Victoria; 2018. Available from: http://www.tobaccoinaustralia.org.au/chapter-18-harm-reduction/indepth-18b-e-cigarettes

At the heart of the debate over the utility of e-cigarettes is concern about the extent to which the potential benefits of making a likely-less harmful alternative to tobacco widely available to smokers might be outweighed by several potential risks. Risks identified to date include uptake by non-smokers, gateway effects, dangers associated with dual use, discouragement from cessation, renormalising smoking, and allowing the tobacco industry to influence decision-making in public health.1-3

18B.6.1.Uptake among non-smokers 

Experimentation with e-cigarettes among non-smoking adults appears to be relatively rare.4, 5  Among young people however, use is increasing, in some countries quite rapidly (see Section 18B.3). While initial reports indicated that e-cigarette use occurred predominantly among adolescents who had also experimented with tobacco,6 more recent data shows increasing use among never smokers.7 An analysis of trends from 2011 to 15 in e-cigarette use among US adolescents found that over time, past month e-cigarette users increasingly encompassed those who were not users of other tobacco products.8 During 2017–2018, current e-cigarette use among US high school students increased by 78% (from 11.7% to 20.8%),9 and the FDA has labelled the substantial increase in e-cigarette use among youth an ‘epidemic’.10 Among adults, one study reported that in 2016 in the US, 1.4% of never smokers reported vaping, and of these users, about 60% were aged 18 to 24.11  

Use of e-cigarettes by children and non-smokers—either as a step toward smoking (see Section 18B.6.2, below) or exclusively—is a concern to public health specialists and regulators. Exposure to nicotine during adolescence may have significant and lasting health consequences,12 including long-term addiction to e-cigarette delivered nicotine.13 One of the most popular e-cigarette brands in the US among youth, JUUL, exposes users to high levels of nicotine;14 however one study found that only four in ten (37%) past-month users knew the product always contains nicotine.15 Further, although the adverse health effects of e-cigarette use are likely less than those of cigarettes, the long-term consequences are not well understood. Limited evidence suggests that vaping—particularly when e-liquids include sweet flavourings16, 17 —may increase users’ risks of cardiovascular and respiratory disease (see Section 18B.5). Some adolescents are also using e-cigarettes for vaping of cannabis and other substances which pose additional risks (see Section 18B.4).18  

As with tobacco cigarettes, exposure to e-cigarette marketing and promotion is associated with greater e-cigarette use among young people,19-22 with ads for flavoured e-cigarettes potentially being more appealing to children than those for non-flavoured products23 (see Section 18B.2.3). Along with curiosity, the wide range of fruit, candy, and other sweet flavours is one of the most commonly cited reasons for experimentation among children.24-27 Although such flavours have been banned in conventional cigarettes in Australia28-33 and the US34 largely due to their appeal to children, and despite the high levels of toxic compounds found in flavoured e-cigarettes,35, 36 it has been estimated that there are over 7500 different flavours of e-liquid available.37

Together, these issues have led to calls for strict regulations that would minimise use among young people and non-smokers, including restrictions on advertising and promotion, prohibiting use in smokefree areas, banning flavours that could appeal to youth, raising taxes, implementing health warnings, and prohibiting sales to minors.38, 39 In 2018, the FDA launched a public education campaign to educate teenagers about the risks of e-cigarettes, and proposed having flavoured e-cigarettes (other than tobacco, mint and menthol flavours) only sold in age-restricted, in-person locations and, if sold online, under heightened practices for age verification.10, 40

18B.6.2 A ‘gateway effect’ to tobacco smoking 

Of great concern to public health experts is the growing body of research suggesting a possible relationship between e-cigarette use and the uptake and escalation of smoking among young people.  A 2016 meta-analysis concluded that never-smoking adolescents and young adults who use e-cigarettes are more likely to intend to smoke,41 and a systematic review in the same year concluded that e-cigarette use is associated with an increase in smoking, even among adolescents not susceptible to smoking.42 A major review published in 2018 concluded that there is substantial evidence that e-cigarette use increases risk of ever using combustible tobacco cigarettes among youth and young adults,43 and another concluded that the evidence for a strong positive relationship between use of e-cigarettes and later cigarette smoking among youth continues to accumulate.44 Use of e-cigarettes among youth and young adults may also increase consumption of conventional cigarettes and duration of smoking.43

Such studies cannot establish causation (i.e., vaping could be a marker in young people who would have gone onto use conventional cigarettes regardless; one cannot rule out the possibility that the relationship between e-cigarette use and smoking is explained by another/other variable/s). However several studies have noted conventional cigarette uptake among e-cigarette users who would be considered least at risk of smoking,42, 45, 46 and the best-quality studies and reviews have attempted to control for underlying susceptibility. Several possible mechanisms of how vaping may act as a ‘gateway’ to smoking have been proposed. E-cigarette use could normalise nicotine use and smoking behaviours more generally, leading to the renormalisation of smoking, or it could cause users to develop nicotine addiction.41, 45 The use of e-cigarettes with higher concentrations of nicotine has a stronger association to later cigarette use.44  

Alternatively, some have suggested that, rather than acting as a ‘gateway’, e-cigarettes may be acting as a ‘diversion’ among young people. That is, vaping partially or wholly replaces cigarette smoking, and may therefore accelerate the decline in youth cigarette smoking.47 They note that increases in use of non-cigarette tobacco/nicotine products has increased substantially in the US in recent years, alongside a decline in cigarette smoking.47 However, critics of this theory argue that there was no acceleration in the decline of youth cigarette use after e-cigarettes emerged, and continued declines in smoking can be attributed to comprehensive tobacco control programs.48

18B.6.3 Prolonged dual use 

Dual use refers to the concurrent use of conventional tobacco products and e-cigarettes.  Dual use is actively promoted by some e-cigarette manufacturers, especially those that also manufacture tobacco products, as a way for smokers to by-pass smokefree regulations,37 and this is a commonly cited reason for vaping among smokers.49, 50 Other smokers use both products as a means of cutting down the number of cigarettes they smoke each day, and/or as an intended pathway to complete smoking cessation.51, 52 However, many smokers are unsuccessful in transitioning fully from smoking to vaping, despite initial intentions to quit smoking.49  

While a reduction in risk seems likely for smokers who completely substitute tobacco cigarettes,53, 54 the benefits for those who continue to use some tobacco cigarettes are much less certain. Among those who exclusively smoke tobacco cigarettes, cutting down the number of cigarettes consumed may not reduce toxic exposure if smokers compensate by drawing more deeply on the cigarettes they do smoke. There is some evidence that supplementing reduced cigarette consumption with an alternative source of nicotine might reduce toxicant exposure and hence mortality among smokers who continue to smoke at a reduced rate—see section 18B.7.3 55-57  However, there is no available evidence whether or not long-term e-cigarette use among smokers changes morbidity or mortality compared with those who only smoke tobacco cigarettes.43 Use of e-cigarettes has the potential to introduce independent or additive health risks.44, 58   

18B.6.4 Discouragement from cessation 

Smokers taking up e-cigarettes while still smoking tobacco cigarettes, who might otherwise have quit altogether had they not commenced e-cigarette use, might represent missed opportunities for complete cessation. So far, although many current and former smokers state a preference for e-cigarettes as a cessation aid, the effectiveness of e-cigarettes for prompting or supporting cessation is unknown.44  Evidence to date suggests that smokers who use e-cigarette intensively may be more likely to quit conventional cigarettes,59-62 however intermittent users—who comprise the majority of users—may be less likely to quit.59, 62 (see Section 18B.7). At a population level, several studies have suggested that use of e-cigarettes is unlikely to lead to a meaningful increase in quit rates.63, 64

Smoking poses a very significant risk to health both in the immediate and the longer term, but the most serious diseases emerge only with long-term use. While two of every three long term smokers in Australia will die from smoking, quitting prior to age 45 reduces mortality risk close to that of never smokers.65 Given that complete cessation of use of any nicotine product is the option associated with least harm, it follows that the optimal approach for younger smokers at least in the first instance would be to attempt to quit without continuing use of nicotine. 

18B.6.5 The renormalisation of smoking

Decades of successful public health campaigning have profoundly denormalised smoking. As evidence has accumulated about the hazards of tobacco to smokers and non-smokers alike, stronger public health measures—including restrictions on smoking—have been widely adopted.66 Those advocating caution about e-cigarettes have characterised these new products as having the potential to weaken these tobacco control efforts and help to renormalise smoking.66, 67 E-cigarette use among young people is especially worrying if e-cigarettes promote the normalisation of nicotine use and smoking behaviour, and subsequently lead to long-term use among those who would otherwise never have vaped or smoked.43

It has also been argued that e-cigarettes could revive the behaviour of smoking in public, undermining increasingly stringent restrictions on smoking in both indoor and outdoor areas.1 Dual users of e-cigarettes and cigarettes commonly report using the products to circumvent no-smoking policies,49, 50 and in the face of increasing restrictions on e-cigarette use in smokefree environments, many users report vaping discreetly in places where such use is prohibited.68 However, it is unknown whether the growing acceptance and use of e-cigarettes affects acceptance of cigarette smoking, or regulations to discourage smoking.44 Some have argued that e-cigarettes are easily distinguishable in appearance and smell from tobacco cigarettes, and that widespread use of e-cigarettes is more likely to normalise alternative nicotine devices than smoking, and may benefit and support smokefree environments.6

18B.6.6 Potential to reinvolve the tobacco industry in public health policy 

Although e-cigarettes were originally developed and marketed independently from the tobacco industry, some of the world’s largest tobacco companies have heavily invested in the market—see Section 18B.1.3. Given its history of unethically promoting and defending tobacco cigarettes, the tobacco industry’s involvement in e-cigarettes is of great concern to public health experts. The tobacco industry is said to be pursuing five goals: promoting widespread dual use; hindering smoking cessation; renormalising public smoking; conveying to young people that nicotine is a benign drug; and welcoming back lapsed smokers.1 Concerns have also been raised regarding the quality of research on e-cigarettes, with one systematic review finding many serious methodological shortcomings. In 34% of the papers reviewed, the authors had a conflict of interest. Most studies were funded or otherwise supported/influenced by manufacturers of e-cigarettes (including the tobacco industry), which appeared to influence the conclusions of the papers.69

As well as enjoying commercial gains from investing in e-cigarettes, it has been argued that tobacco companies are likely to be keen to exploit opportunities for advertising and promotion that will promote tobacco and/or e-cigarette use.6 Many e-cigarette advertisements resemble traditional tobacco advertising.70 By becoming involved in alternative nicotine delivery products, companies may be able to evade current restrictions on engagement in policy imposed by Article 5.3 of the Framework Convention on Tobacco Control (FCTC).6 In response to concerns regarding the possibility of e-cigarettes interfering with existing tobacco control efforts, the WHO has invited FCTC Parties to “protect tobacco-control activities from all commercial and other vested interests related to [electronic nicotine delivery systems], including interests of the tobacco industry”.71 


Relevant news and research

For recent news items and research on this topic, click here. ( Last updated September 2019)


1. Chapman S. Should electronic cigarettes be as freely available as tobacco cigarettes? No. British Medical Journal, 2013; 346:f3840. Available from: https://www.ncbi.nlm.nih.gov/pubmed/23771038

2. Etter J. Should electronic cigarettes be as freely available as tobacco? Yes. British Medical Journal, 2013; 346:f3845. Available from: https://www.ncbi.nlm.nih.gov/pubmed/23771039

3. Kalkhoran S and Glantz SA. Modeling the health effects of expanding e-cigarette sales in the United States and United Kingdom: A Monte Carlo analysis. JAMA Internal Medicine, 2015; 175(10):1671–80. Available from: http://www.ncbi.nlm.nih.gov/pubmed/26322924

4. Hajek P, Etter JF, Benowitz N, Eissenberg T, and McRobbie H. Electronic cigarettes: Review of use, content, safety, effects on smokers and potential for harm and benefit. Addiction, 2014; 109(11):1801–10. Available from: http://www.ncbi.nlm.nih.gov/pubmed/25078252

5. Australian Institute of Health and Welfare. National Drug Strategy Household Survey detailed report: 2013. Cat. no. PHE 183 Canberra: AIHW, 2014. Available from: http://www.aihw.gov.au/publication-detail/?id=60129549469&tab=3

6. Britton J and Bogdanovica I. Electronic cigarettes: A report commissioned by public health England.  2014. Available from: https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/311887/Ecigarettes_report.pdf

7. Barrington-Trimis JL, Urman R, Leventhal AM, Gauderman WJ, Cruz TB, et al. E-cigarettes, cigarettes, and the prevalence of adolescent tobacco use. Pediatrics, 2016; 138(2). Available from: http://www.ncbi.nlm.nih.gov/pubmed/27401102

8. Chaffee B, Couch E, and Gansky S. Trends in characteristics and multi-product use among adolescents who use electronic cigarettes, United States 2011-2015. PLoS ONE, 2017; 12(5):e0177073. Available from: http://www.ncbi.nlm.nih.gov/pubmed/28475634

9. Cullen KA, Ambrose BK, Gentzke AS, Apelberg BJ, Jamal A, et al. Notes from the field: Use of electronic cigarettes and any tobacco product among middle and high school students - United States, 2011-2018. Morbidity and Mortality Weekly Report, 2018; 67(45):1276–7. Available from: http://www.ncbi.nlm.nih.gov/pubmed/30439875

10. US Food & Drug Administration. Statement from FDA commissioner scott gottlieb, m.D., on launch of ‘the real cost’ youth e-cigarette prevention campaign amid evidence of sharply rising use among kids.  2018. Available from: https://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm620791.htm

11. Mirbolouk M, Charkhchi P, Orimoloye OA, and et al. E-cigarette use without a history of combustible cigarette smoking among US adults: Behavioral risk factor surveillance system, 2016. Annals of Internal Medicine, 2018. Available from: http://dx.doi.org/10.7326/M18-1826

12. England LJ, Bunnell RE, Pechacek TF, Tong VT, and McAfee TA. Nicotine and the developing human: A neglected element in the electronic cigarette debate. American Journal of Preventive Medicine, 2015; 49(2):286–93. Available from: http://www.ncbi.nlm.nih.gov/pubmed/25794473

13. Klein JD. Electronic cigarettes are another route to nicotine addiction for youth. JAMA Pediatrics, 2015:1–2. Available from: http://www.ncbi.nlm.nih.gov/pubmed/26349006

14. Goniewicz ML, Boykan R, Messina CR, Eliscu A, and Tolentino J. High exposure to nicotine among adolescents who use juul and other vape pod systems ('pods'). Tobacco Control, 2018. Available from: https://www.ncbi.nlm.nih.gov/pubmed/30194085

15. Willett JG, Bennett M, Hair EC, Xiao H, Greenberg MS, et al. Recognition, use and perceptions of juul among youth and young adults. Tobacco Control, 2018. Available from: https://tobaccocontrol.bmj.com/content/tobaccocontrol/early/2018/04/07/tobaccocontrol-2018-054273.full.pdf

16. Leigh NJ, Lawton RI, Hershberger PA, and Goniewicz ML. Flavourings significantly affect inhalation toxicity of aerosol generated from electronic nicotine delivery systems (ends). Tobacco Control, 2016; 25(Suppl 2):ii81–ii7. Available from: http://tobaccocontrol.bmj.com/content/25/Suppl_2/ii81.abstract

17. Tierney P, Karpinski C, Brown J, Luo W, and Pankow J. Flavour chemicals in electronic cigarette fluids. Tobacco Control, 2016; 25(e1):e10–5. Available from: http://tobaccocontrol.bmj.com/content/early/2015/03/27/tobaccocontrol-2014-052175.full

18. Moore G, Hewitt G, Evans J, Littlecott H, Holliday J, et al. Electronic-cigarette use among young people in Wales: Evidence from two cross-sectional surveys. BMJ Open, 2015; 5(4):e007072. Available from: http://bmjopen.bmj.com/content/5/4/e007072.full

19. Singh T, Agaku IT, Arrazola RA, Marynak KL, Neff LJ, et al. Exposure to advertisements and electronic cigarette use among US middle and high school students. Pediatrics, 2016; 137(5). Available from: http://www.ncbi.nlm.nih.gov/pubmed/27244815

20. Mantey DS, Cooper MR, Clendennen SL, Pasch KE, and Perry CL. E-cigarette marketing exposure is associated with e-cigarette use among US youth. The Journal of Adolescent Health, 2016; 58(6):686–90. Available from: http://www.ncbi.nlm.nih.gov/pubmed/27080732

21. Best C, Haseen F, van der Sluijs W, Ozakinci G, Currie D, et al. Relationship between e-cigarette point of sale recall and e-cigarette use in secondary school children: A cross-sectional study. BMC Public Health, 2016; 16(1):310. Available from: http://www.ncbi.nlm.nih.gov/pubmed/27075888

22. Pu J and Zhang X. Exposure to advertising and perception, interest, and use of e-cigarettes among adolescents: Findings from the US national youth tobacco survey. Perspect Public Health, 2017:1757913917703151. Available from: http://www.ncbi.nlm.nih.gov/pubmed/28379069

23. Vasiljevic M, Petrescu DC, and Marteau TM. Impact of advertisements promoting candy-like flavoured e-cigarettes on appeal of tobacco smoking among children: An experimental study. Tobacco Control, 2016. Available from: http://www.ncbi.nlm.nih.gov/pubmed/26781305

24. Measham F, O’Brien K, and Turnbull G. “Skittles & red bull is my favourite flavour”: E-cigarettes, smoking, vaping and the changing landscape of nicotine consumption amongst British teenagers – implications for the normalisation debate. Drugs: Education, Prevention and Policy, 2016; 23(3):224–37. Available from: http://dx.doi.org/10.1080/09687637.2016.1178708

25. Kong G, Morean ME, Cavallo DA, Camenga DR, and Krishnan-Sarin S. Reasons for electronic cigarette experimentation and discontinuation among adolescents and young adults. Nicotine & Tobacco Research, 2015; 17(7):847–54. Available from: http://www.ncbi.nlm.nih.gov/pubmed/25481917

26. Harrell MB, Weaver SR, Loukas A, Creamer M, Marti CN, et al. Flavored e-cigarette use: Characterizing youth, young adult, and adult users. Preventive Medicine Reports, 2017; 5:33–40. Available from: https://www.ncbi.nlm.nih.gov/pubmed/27896041

27. Pepper JK, Ribisl KM, and Brewer NT. Adolescents' interest in trying flavoured e-cigarettes. Tobacco Control, 2016; 25(Suppl 2):ii62–ii6. Available from: http://tobaccocontrol.bmj.com/content/25/Suppl_2/ii62.abstract

28. Public Health (Tobacco) Act 2008 (NSW). s 29. See notice contained in New South Wales Government Gazette dated 15 January 2010, at 136. 

29. Public Health Act 1997 (TAS). s 68A(c)-(e). 

30. Tobacco and Other Smoking Products Act 1927 (ACT). s 21. See notice contained in Tobacco (Prohibited Smoking Products) Declaration 2011 (No 1) (Notifiable instrument NI2011-584). 

31. Tobacco and other Smoking Products Act 1998 (QLD). S 26zt. 

32. Tobacco Products Regulation Act 1997 (SA). s 34A. See notice contained in South Australian Government Gazette dated 10 August 2006, at 2640. 

33. Victorian Government Gazette No S 350. Order under section 15N of the Tobacco Act 1987: Banning the sale of certain products. 21 October 2011. Available from: http://www.gazette.vic.gov.au/gazette/Gazettes2011/GG2011S350.pdf

34. US Food and Drug Administration (FDA). Deeming – extending authorities to additional tobacco products. 2015. Available from: http://www.fda.gov/TobaccoProducts/Labeling/ucm388395.htm

35. Farsalinos KE, Kistler KA, Gillman G, and Voudris V. Evaluation of electronic cigarette liquids and aerosol for the presence of selected inhalation toxins. Nicotine & Tobacco Research, 2014; 17(2):168–74. Available from: http://www.ncbi.nlm.nih.gov/pubmed/25180080

36. Allen JG, Flanigan SS, LeBlanc M, Vallarino J, MacNaughton P, et al. Flavoring chemicals in e-cigarettes: Diacetyl, 2,3-pentanedione, and acetoin in a sample of 51 products, including fruit-, candy-, and cocktail-flavored e-cigarettes. Environmental Health Perspectives, 2016; 124(6):733–9. Available from: http://www.ncbi.nlm.nih.gov/pubmed/26642857

37. Zhu SH, Sun JY, Bonnevie E, Cummins SE, Gamst A, et al. Four hundred and sixty brands of e-cigarettes and counting: Implications for product regulation. Tobacco Control, 2014; 23 Suppl 3:iii3–9. Available from: http://www.ncbi.nlm.nih.gov/pubmed/24935895

38. Lindblom EN. Effectively regulating e-cigarettes and their advertising—and the first amendment. Food & Drug Law Journal, 2015; 70:57–94. Available from: http://www.law.georgetown.edu/oneillinstitute/news/documents/March10-LindblomFDLJ_001.pdf

39. Krawitz M. We didn't start this fireless vapour: E-cigarette legislation in Australia. Journal of Law and Medicine, 2014; 22(2):462–81. Available from: http://www.ncbi.nlm.nih.gov/pubmed/25715544

40. US Food & Drug Administration. Statement from FDA commissioner scott gottlieb, m.D., on proposed new steps to protect youth by preventing access to flavored tobacco products and banning menthol in cigarettes. 2018. Available from: https://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm625884.htm

41. Zhong J, Cao S, Gong W, Fei F, and Wang M. Electronic cigarettes use and intention to cigarette smoking among never-smoking adolescents and young adults: A meta-analysis. International Journal of Environmental Research and Public Health, 2016; 13(5). Available from: http://www.ncbi.nlm.nih.gov/pubmed/27153077

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43. National Academies of Sciences Engineering and Medicine. Public health consequences of e-cigarettes. The National Academies Press, Washington, DC 2018. Available from: http://nationalacademies.org/hmd/Reports/2018/public-health-consequences-of-e-cigarettes.aspx

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