18B.4 Safety and abuse potential

Last updated: October 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

18B4.1 Safety risks

18B4.1.1 Explosions, fires and burns

As the popularity of e-cigarettes has increased, there have been growing reports of fires and burn injuries attributed to e-cigarette battery explosions.1-8 An analysis of e-cigarette explosion and burn injuries presenting to US hospital emergency departments (EDs) between 2015 and 2017 concluded that past reports appear to substantially underestimate the actual number of these events. It estimated that there were 2035 presentations over this period—between 15 and 40 times more than previous estimates. The true number of injuries also likely exceeds these estimates, given that people with less severe injuries are less likely to present to an ED.9  

A 2017 review of burns associated with e-cigarette batteries found that the most frequent sites of injury involved the lower extremities and hands. Nearly half of the reported incidences required surgical management as a result of the depth of injury.1 An analysis of e-cigarette-related burns cases presenting to US emergency departments in 2016 found that most of the burns were thermal and occurred to the upper leg/lower trunk. Many occurred when the device was in users’ pockets.10 There have also been case reports of such explosions causing fractures11 and ocular injuries.12 A man was reportedly killed in late 2014 when a charging e-cigarette exploded and ignited his oxygen equipment.13  

Following several fires, in 2015 the International Civil Aviation Organization prohibited airplane passengers and crew from carrying e-cigarettes and other battery-powered portable electronic smoking devices in checked baggage, and from recharging the devices in aircraft cabins.14  

Although e-cigarette manufacturers have tended to attribute blame for explosions to the user for charging the devices improperly, a 2017 report from the US Fire Administration found that only 25 per cent of explosions occurred during the charging process. Sixty-two per cent of the devices exploded when being carried in a pocket or when they were actively in use. It notes that the shape and construction of e-cigarettes is itself problematic. Unlike other products such as mobile phones and laptops, e-cigarettes include cylindrical lithium-ion batteries installed in a cylindrical tube—one that is weakest at both ends. Battery failures generate increased pressure that “shoots” the batteries out of the tube like “rockets.” The report concludes that:

Lithium-ion batteries should not be used in e-cigarettes. While the number of batteries that explode and catch fire is statistically small, the catastrophic nature of the injuries that can occur warrants the use of another battery technology for e-cigarettes.15

18B4.1.2 Nicotine toxicity and accidental poisoning

The nicotine content of e-cigarettes typically ranges between 0 and 34mg/mL;16 although several studies have reported discrepancies between labelled and measured nicotine content.17, 18 At high enough doses, nicotine has acute toxicity.19 Vaping is unlikely to cause nicotine overdose or intoxication, since the amount consumed and absorbed is quite low and comparable to smoking.20-22 However, some e-liquid cartridges contain nicotine doses that are potentially toxic in adults and children if used in ways other than intended.23 Intentional or accidental exposure to e-liquids can cause adverse health effects such as seizures, anoxic brain injury, vomiting, lactic acidosis, and death.24 In recent years there have been increasing numbers of calls to poison information centres due to unintended ingestion of the e-liquid,25, 26 particularly by children,27-29 with a baby in the US30 and a toddler in Israel31 reportedly dying after drinking from an e-cigarette refill bottle. The implementation of  legislation requiring child-resistant packaging for liquid nicotine containers in the US appears to have reduced exposures to liquid nicotine among young children.32 There have also been limited reports of intentional intoxication by injection and ingestion and a small number of suicide attempts associated with the cartridges.33-35 E-cigarettes may also leak, presenting a hazard as nicotine can be absorbed through the skin.36  

18B4.2 Abuse potential

18B4.2.1 Nicotine addiction

Nicotine is among the most addictive of substances known.37, 38 Although e-cigarette users appear to be less dependent on their product than comparable smokers,39-41 most users still considered themselves to be addicted.40 E-cigarettes may deliver systemic nicotine concentrations in a similar range to,16, 42 or even in excess of,43 those delivered by combustible cigarettes. 

Nicotine absorption and dependency depends on how the e-cigarettes are used; types of puffs and intensity can determine the amounts of nicotine inhaled, in addition to the nicotine concentration of the e-liquid.44 Some policy makers have suggested reducing the nicotine concentration in e-liquid to reduce the addictive potential of the products. For example, in the EU, nicotine content is limited to 20mg/ml. However, research suggests that among experienced vapers, such reductions do not translate to a reduction in nicotine absorption, possibly due to compensatory puffing.45, 46   

Nicotine addiction is discussed further in Chapter 6 - Addiction

18B4.2.2 Vaping of other drugs

Along with nicotine, there are concerns that e-cigarettes are being used to consume cannabis, particularly among young people.47, 48 Estimates of ever using an e-cigarette to use cannabis products in youth and young adult samples across North America range from 8 percent to 29 percent.24 Cannabinoid-enriched e-liquids are available for purchase online, or users can also reportedly download recipes and attempt to make their own cannabis e-liquid.49 With the increasing legalisation of cannabis, the e-cigarette and cannabis industries and customer bases are likely to become increasingly intertwined.24

A review of the health effects of cannabis-vaping reached similar conclusions to the general literature: cannabis-vaping is likely less harmful than smoking traditional joints; cannabis e-liquids are unregulated and lack any toxicological and clinical assessment; both cannabis and nicotine pose risks to the neurodevelopment of young people, and also increase their risk of addiction; data on the potential health consequences of vaping cannabis for users and bystanders is extremely limited, and further research is urgently needed.49 Some have suggested that e-cigarettes show promise for the safe and efficient administration of medicinal cannabis.50  

E-cigarettes can also be used to vape other types of drugs.49 A review of e-cigarettes as an illicit drug delivery system found evidence of current use of e-cigarettes to vape almost all illicit drug types analysed. The authors highlighted that such use (via an easy to administer route and tool) may lead to higher levels and unusual patterns of drug use (continuous versus acute administration), potential increases in young adult use, addiction and toxicity, and paediatric accidental exposure.51 Data on the prevalence of this type of use is limited, although an online survey of UK adults found that of the respondents that had used an electronic vaping device, more than one third (39.5%) had ever used them to vape recreational drugs, and more than one quarter (27.4%) reported current use. The most common drug vaped was cannabis (lifetime use 65.7%). Lifetime use was also high for vaping MDMA/’ecstasy’ (42.8%), cocaine powder (39.8%), mephedrone (30.9%), crack cocaine (30.5%), synthetic cannabinoid receptor agonists (28.4%), fentanyl (26.7%), heroin (25.8%), alpha-PVP (alpha-pyrrolidinopentiophenone)(25.8%), typtamines (25.4%), NBOMe (2, 5-dimethoxy-4-bromophenethylamine) (25%) and ketamine (24.6%).52

18B4.2.3 “Dripping”

E-cigarettes typically deliver e-liquid to the heating coil via saturated wicking material; however, “dripping” involves users putting a few drops of e-liquid directly onto an atomiser’s coil and then immediately inhaling the vapour that is produced.53 Limited evidence suggests that dripping can expose users to high temperatures and toxic chemicals such as aldehydes.54  

One study in Colorado found that among high school students who had ever used e-cigarettes, about one quarter (26.1%) had used the product for dripping.53 However, the study was criticised for inadequately defining and measuring the concept.55 Further research is needed regarding the use and health effects of dripping, both for consumer information and to inform regulations.56    

Relevant news and research

For recent news items and research on this topic, click here. ( Last updated June 2022)



1. Harshman J, Vojvodic M, and Rogers AD. Burns associated with e-cigarette batteries: A case series and literature review. CJEM, 2017:1–9. Available from: http://www.ncbi.nlm.nih.gov/pubmed/28566106

2. Jiwani AZ, Williams JF, Rizzo JA, Chung KK, King BT, et al. Thermal injury patterns associated with electronic cigarettes. Int J Burns Trauma, 2017; 7(1):1–5. Available from: http://www.ncbi.nlm.nih.gov/pubmed/28123861

3. Kumetz EA, Hurst ND, Cudnik RJ, and Rudinsky SL. Electronic cigarette explosion injuries: A case series. American Journal of Emergency Medicine, 2016. Available from: http://www.ncbi.nlm.nih.gov/pubmed/27133537

4. Nicoll KJ, Rose AM, Khan MA, Quaba O, and Lowrie AG. Thigh burns from exploding e-cigarette lithium ion batteries: First case series. Burns, 2016. Available from: http://www.ncbi.nlm.nih.gov/pubmed/27118069

5. Ramirez JI, Ridgway CA, Lee JG, Potenza BM, Sen S, et al. The unrecognized epidemic of electronic cigarette burns. Journal of Burn Care & Research, 2017; 38(4):220–4. Available from: http://www.ncbi.nlm.nih.gov/pubmed/28644205

6. Sheckter C, Chattopadhyay A, Paro J, and Karanas Y. Burns resulting from spontaneous combustion of electronic cigarettes: A case series. Burns Trauma, 2016; 4:35. Available from: http://www.ncbi.nlm.nih.gov/pubmed/27995151

7. Treitl D, Solomon R, Davare DL, Sanchez R, and Kiffin C. Full and partial thickness burns from spontaneous combustion of e-cigarette lithium-ion batteries with review of literature. The Journal of Emergency Medicine, 2017. Available from: http://www.ncbi.nlm.nih.gov/pubmed/28501385

8. U.S. Fire Administration. Electronic cigarette fires and explosions. 2014. Available from: https://www.usfa.fema.gov/downloads/pdf/publications/electronic_cigarettes.pdf

9. Rossheim ME, Livingston MD, Soule EK, Zeraye HA, and Thombs DL. Electronic cigarette explosion and burn injuries, US emergency departments 2015-2017. Tob Control, 2018. Available from: https://www.ncbi.nlm.nih.gov/pubmed/30219795

10. Corey CG, Chang JT, and Rostron BL. Electronic nicotine delivery system (ends) battery-related burns presenting to US emergency departments, 2016. Injury Epidemiology, 2018; 5(1):4. Available from: https://doi.org/10.1186/s40621-018-0135-1

11. Norii T and Plate A. Electronic cigarette explosion resulting in a c1 and c2 fracture: A case report. Journal of Emergency Medicine, 2017; 52(1):86–8. Available from: http://www.ncbi.nlm.nih.gov/pubmed/27712901

12. Paley GL, Echalier E, Eck TW, Hong AR, Farooq AV, et al. Corneoscleral laceration and ocular burns caused by electronic cigarette explosions. Cornea, 2016. Available from: http://www.ncbi.nlm.nih.gov/pubmed/27191672

13. No authors listed. Man killed as e-cigarette 'explodes', merseyside fire service says. BBC News, 2014. Available from: http://www.bbc.com/news/uk-england-merseyside-28701515

14. International Civil Aviation Organization. ICAO confirms new e-cigarette restrictions. 2015. Available from: http://www.icao.int/Newsroom/Pages/ICAO-Confirms-New-E-Cigarette-Restrictions.aspx

15. U.S. Fire Administration. Electronic cigarette fires and explosions in the United States 2009 - 2016. Federal Emergency Management Agency, 2017. Available from: https://www.usfa.fema.gov/downloads/pdf/publications/electronic_cigarettes.pdf

16. Schroeder MJ and Hoffman AC. Electronic cigarettes and nicotine clinical pharmacology. Tobacco Control, 2014; 23 (Suppl 2):ii30–5. Available from: http://www.ncbi.nlm.nih.gov/pubmed/24732160

17. Goniewicz M, Kuma T, Gawron M, Knysak J, and Kosmider L. Nicotine levels in electronic cigarettes. Nicotine & Tobacco Research, 2013; 15:158–66. Available from: http://ntr.oxfordjournals.org/content/early/2012/04/21/ntr.nts103

18. Buettner-Schmidt K, Miller DR, and Balasubramanian N. Electronic cigarette refill liquids: Child-resistant packaging, nicotine content, and sales to minors. Journal of Pediatric Nursing, 2016. Available from: http://www.ncbi.nlm.nih.gov/pubmed/27079973

19. U.S. Department of Health and Human Services. The health consequences of smoking: 50 years of progress. A report of the Surgeon General. Atlanta, GA: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for Chronic Disease Prevention and Health Promotion, Office on Smoking and Health, 2014. Available from: http://www.surgeongeneral.gov/library/reports/50-years-of-progress/full-report.pdf.

20. Farsalinos KE, Romagna G, Tsiapras D, Kyrzopoulos S, and Voudris V. Evaluation of electronic cigarette use (vaping) topography and estimation of liquid consumption: Implications for research protocol standards definition and for public health authorities’ regulation. International Journal of Environmental Research and Public Health, 2013; 10(6):2500–14. Available from: http://www.ncbi.nlm.nih.gov/pubmed/23778060

21. Nides MA, Leischow SJ, Bhatter M, and Simmons M. Nicotine blood levels and short-term smoking reduction with an electronic nicotine delivery system. American Journal of Health Behavior, 2014; 38(2):265–74. Available from: http://www.ncbi.nlm.nih.gov/pubmed/24629555

22. Dawkins L and Corcoran O. Acute electronic cigarette use: Nicotine delivery and subjective effects in regular users. Psychopharmacology, 2014; 231(2):401–7. Available from: http://www.ncbi.nlm.nih.gov/pubmed/23978909

23. Cameron JM, Howell DN, White JR, Andrenyak DM, Layton ME, et al. Variable and potentially fatal amounts of nicotine in e-cigarette nicotine solutions. Tobacco Control, 2014; 23(1):77–8. Available from: http://tobaccocontrol.bmj.com/content/23/1/77.short

24. 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.

25. Centers for Disease Control and Prevention. Press release: ‘New CDC study finds dramatic increase in e-cigarette-related calls to poison centers’. 2014. Available from: http://www.cdc.gov/media/releases/2014/p0403-e-cigarette-poison.html

26. Branley A. Health experts alarmed after rise in accidental poisoning from e-cigarettes. ABC News, 2014. Available from: http://www.abc.net.au/news/2014-08-27/accidental-poisoning-from-ecigarettes-on-the-rise/5699592

27. 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

28. Hagen K. E-cigarettes poisoning Victorian toddlers. The Age, 2014. Available from: http://www.theage.com.au/national/ecigarettes-poisoning-victorian-toddlers-20140606-39ohu.html?skin=text-only

29. Kamboj A, Spiller HA, Casavant MJ, Chounthirath T, and Smith GA. Pediatric exposure to e-cigarettes, nicotine, and tobacco products in the United States. Pediatrics, 2016; 137(6). Available from: http://www.ncbi.nlm.nih.gov/pubmed/27244861

30. Withnall A. First 'e-cigarette child death': New York baby dies after drinking liquid nicotine. The Independent, 2014. Available from: http://www.independent.co.uk/news/world/americas/first-ecigarette-child-death-new-york-baby-dies-after-drinking-liquid-nicotine-9924229.html

31. Winer S. Police investigating toddler’s death from nicotine overdose. The Times of Israel, 2013. Available from: http://www.timesofisrael.com/police-investigating-toddler-death-from-nicotine-overdose/

32. Govindarajan P, Spiller HA, Casavant MJ, Chounthirath T, and Smith GA. E-cigarette and liquid nicotine exposures among young children. Pediatrics, 2018. Available from: https://www.ncbi.nlm.nih.gov/pubmed/29686144

33. Cervellin G, Luci M, Bellini C, and Lippi G. Bad news about an old poison. A case of nicotine poisoning due to both ingestion and injection of the content of an electronic cigarette refill. Emergency Care Journal, 2013; 9(2):18. Available from: http://ftp.oncologyreviews.org/index.php/ecj/article/view/ecj.2013.e18

34. Christensen LB, van’t Veen T, and Bang J. Three cases of attempted suicide by ingestion of nicotine liquid used in e-cigarettes. XXXIII International Congress of the European Association of Poisons Centres and Clinical Toxicologists (EAPCCT), 2013. Available from: http://www.e-cigarette-research.info/doku.php/research:documents:f87h87fv

35. Park EJ and Min YG. The emerging method of suicide by electronic cigarette liquid: A case report. Journal of Korean Medical Science, 2018; 33(11):e52. Available from: https://www.ncbi.nlm.nih.gov/pubmed/29495133

36. National Institure for Health and Care Excellence. Tobacco: Harm-reduction approaches to smoking. NICE public health guidance 45, 2013. Available from: http://www.nice.org.uk/guidance/ph45/resources/guidance-tobacco-harmreduction-approaches-to-smoking-pdf

37. Royal College of Physicians of London. Nicotine addiction in Britain. A report of the tobacco advisory group of the royal college of physicians. London: Royal College of Physicians of London, 2000. Available from: http://www.rcplondon.ac.uk/pubs/books/nicotine/.

38. Benowitz N. Nicotine addiction. New England Journal of Medicine, 2010; 362(24):2295–303. Available from: http://content.nejm.org/cgi/content/full/362/24/2295

39. Etter JF and Eissenberg T. Dependence levels in users of electronic cigarettes, nicotine gums and tobacco cigarettes. Drug and Alcohol Dependence, 2015; 147:68–75. Available from: http://www.ncbi.nlm.nih.gov/pubmed/25561385

40. Liu G, Wasserman E, Kong L, and Foulds J. A comparison of nicotine dependence among exclusive e-cigarette and cigarette users in the path study. Preventive Medicine, 2017. Available from: http://www.ncbi.nlm.nih.gov/pubmed/28389330

41. Rostron BL, Schroeder MJ, and Ambrose BK. Dependence symptoms and cessation intentions among US adult daily cigarette, cigar, and e-cigarette users, 2012-2013. BMC Public Health, 2016; 16(1):814. Available from: http://www.ncbi.nlm.nih.gov/pubmed/27538489

42. Shahab L, Goniewicz ML, Blount BC, Brown J, McNeill A, et al. Nicotine, carcinogen, and toxin exposure in long-term e-cigarette and nicotine replacement therapy users: A cross-sectional study. Annals of Internal Medicine, 2017. Available from: http://www.ncbi.nlm.nih.gov/pubmed/28166548

43. Ramoa CP, Hiler MM, Spindle TR, Lopez AA, Karaoghlanian N, et al. Electronic cigarette nicotine delivery can exceed that of combustible cigarettes: A preliminary report. Tobacco Control, 2016; 25(e1):e6–9. Available from: http://www.ncbi.nlm.nih.gov/pubmed/26324250

44. Byrne S, Brindal E, Williams G, Anastasiou K, Tonkin A, et al. E-cigarettes, smoking and health. A literature review update. CSIRO, Australia, 2018. Available from: https://www.csiro.au/en/Research/BF/Areas/Nutrition-and-health/E-cigarettes-report

45. Soar K, Kimber C, McRobbie H, and Dawkins LE. Nicotine absorption from e-cigarettes over 12 months. Addictive Behaviors, 2018. Available from: https://www.ncbi.nlm.nih.gov/pubmed/30054021

46. Kosmider L, Kimber CF, Kurek J, Corcoran O, and Dawkins LE. Compensatory puffing with lower nicotine concentration e-liquids increases carbonyl exposure in e-cigarette aerosols. Nicotine & Tobacco Research, 2018; 20(8):998–1003. Available from: https://www.ncbi.nlm.nih.gov/pubmed/29065196

47. Morean ME, Kong G, Camenga DR, Cavallo DA, and Krishnan-Sarin S. High school students' use of electronic cigarettes to vaporize cannabis. Pediatrics, 2015; 136(4):611–6. Available from: http://www.ncbi.nlm.nih.gov/pubmed/26347431

48. Cassidy RN, Meisel MK, DiGuiseppi G, Balestrieri S, and Barnett NP. Initiation of vaporizing cannabis: Individual and social network predictors in a longitudinal study of young adults. Drug and Alcohol Dependence, 2018; 188:334–40. Available from: https://www.ncbi.nlm.nih.gov/pubmed/29857317

49. Giroud C, de Cesare M, Berthet A, Varlet V, Concha-Lozano N, et al. E-cigarettes: A review of new trends in cannabis use. International Journal of Environmental Research and Public Health, 2015; 12(8):9988–10008. Available from: http://www.ncbi.nlm.nih.gov/pubmed/26308021

50. Lanz C, Mattsson J, Soydaner U, and Brenneisen R. Medicinal cannabis: In vitro validation of vaporizers for the smoke-free inhalation of cannabis. PLoS ONE, 2016; 11(1):e0147286. Available from: http://www.ncbi.nlm.nih.gov/pubmed/26784441

51. Breitbarth AK, Morgan J, and Jones AL. E-cigarettes-an unintended illicit drug delivery system. Drug Alcohol Depend, 2018; 192:98-111. Available from: https://www.ncbi.nlm.nih.gov/pubmed/30245461

52. Blundell MS, Dargan PI, and Wood DM. A cloud on the horizon - a survey into the use of electronic vaping devices for recreational drug and new psychoactive substance administration. QJM, 2017. Available from: https://www.ncbi.nlm.nih.gov/pubmed/29025078

53. Krishnan-Sarin S, Morean M, Kong G, Bold KW, Camenga DR, et al. E-cigarettes and "dripping" among high-school youth. Pediatrics, 2017; 139(3). Available from: http://www.ncbi.nlm.nih.gov/pubmed/28167512

54. Talih S, Balhas Z, Salman R, Karaoghlanian N, and Shihadeh A. "Direct dripping": A high-temperature, high-formaldehyde emission electronic cigarette use method. Nicotine & Tobacco Research, 2016; 18(4):453–9. Available from: http://www.ncbi.nlm.nih.gov/pubmed/25863521

55. Polosa R. Re: E-cigarettes and “dripping” among high-school youth: Interpretation of the findings flawed by vague definition. Pediatrics, 2017. Available from: http://pediatrics.aappublications.org/content/139/3/e20163224.comments

56. Harrell PT and Eissenberg T. Automated dripping devices for vapers: Rdtas, bottomfeeders, squonk mods and dripboxes. Tobacco Control, 2018; 27(4):480–2. Available from: http://tobaccocontrol.bmj.com/content/tobaccocontrol/27/4/480.full.pdf