Paul McNamara is a GP in Glasgow and Honorary Clinical Lecturer at the University of Glasgow. He is on X: @DocPaulMcNamara
Rachel Spence is a 5th year medical student at the University of Glasgow.
Bladder cancer wasn’t even on my patient’s radar. So when the diagnosis came, he was understandably devastated. He wasn’t a smoker — just a regular vaper, convinced it was the ‘safer’ alternative. When he read about potential links between vaping and bladder cancer, he came to me seeking answers. It was a stark reminder of the evolving risks associated with vaping. In general practice, we’re well-versed in the link between tobacco smoking and malignancy. But what about vaping? As its popularity rises, particularly among younger people, we need to ask: what risks are we potentially missing?
Electronic cigarettes (e-cigarettes) heat nicotine-containing liquids into aerosols for inhalation as a substitute to traditional cigarettes for nicotine consumption.1 They commonly contain nicotine, propylene glycol or glycerol, and a flavouring additive.1 The use of e-cigarettes in the UK population as a whole has increased exponentially in the past 11 years, from 700 000 users in 2012 to 4.7 million in 2023,2 with a specific increase being seen in young people and first-time smokers.2 Most notably, experimentation in those aged under 18 years has increased from 7.7% to 11.6% in just 1 year.2,3
“… experimentation [of e-cigarettes] in those aged under 18 years has increased from 7.7% to 11.6% in just 1 year.”
The risks associated with traditional cigarette smoking are well documented.4 As e-cigarettes deliver nicotine by heating a nicotine-containing liquid rather than through tobacco combustion, a potential two-fold benefit is provided;5 it has been shown to be less harmful than cigarette smoking6,7 and may also be contributing to the reducing rates of traditional cigarette smoking in the population.1 In fact, some studies have suggested this to be an effective strategy for achieving cessation in traditional cigarette smokers and a significant tool for tobacco harm reduction.6
The presence of strong carcinogens, known as ‘tobacco-specific nitrosamines’ (TSNAs), is one of the most well-documented risks associated with traditional cigarette smoking;8 however, e-cigarettes are not entirely free from this risk. Studies have shown the presence of similar TSNAs in e-cigarette replacement liquids8 and in samples from e-cigarette users following consumption.9 Given the increasing prevalence of e-cigarette use among younger populations,2 it is important to consider the potential impacts of this.
Bladder cancer is a commonly diagnosed cancer in the UK, and a significant cause of morbidity and mortality.10,11 It most often affects patients aged over 50 years, peaking around 85 years for female patients and 90 years for male patients.10,11 Tobacco consumption is the main risk factor for developing bladder cancer due to DNA damage caused by the many carcinogens present, including TSNAs.11,12
Recent studies have identified certain TSNAs in urine samples of ‘non-traditional cigarette smoking’ e-cigarette users.9,13,14 Several of these carcinogenic biomarkers identified are strongly linked to the development of bladder cancer.13 Additionally, in a recent animal study, e-cigarette smoke caused DNA damage and inhibited DNA repair in mice when compared with a control group exposed only to air. This resulted in transitional cell hyperplasia within the bladder, a potentially precancerous state.15
“Recent studies have identified certain TSNAs [tobacco-specific nitrosamines] in urine samples of ‘non-traditional cigarette smoking’ e-cigarette users.”
A further study assessing the risk factors present in patients diagnosed with bladder cancer noted not only the increased risk of receiving a diagnosis with e-cigarette use, but also the significant difference in age at diagnosis.16 This study found e-cigarette users had an average age of 57 years at diagnosis, compared to 65 years for those with no history of e-cigarette use. The trend seen in this study reflects that of broader demographic trends, where e-cigarette use is becoming increasingly prevalent in younger populations.
A review of smoking trends in England showed that although traditional cigarette smoking declined in those aged 18–44 years, the proportion of e-cigarette use increased.17 E-cigarette use in the ‘never smoked’ population has also increased over the past few years, suggesting this more available and convenient form of consuming nicotine is attracting those who would not have otherwise used nicotine products.17 These results show an overall increase in inhaled nicotine use where, for many years, this habitual practice had been declining.17
The increasing prevalence of e-cigarettes has clearly contributed to the surge in smoking habits among younger people. There are many factors that have facilitated this, including the perceived safety and affordability compared to traditional smoking methods, as well as the convenience and taste of e-cigarettes.17,18 Additionally, the unregulated advertisement of e-cigarettes through social media sites, commonly used by younger populations, is likely to be of influence.17,19 This is in sharp contrast with the Tobacco Advertising and Promotion Act 2002, which strictly prohibits advertisement of traditional cigarettes.
Historically, research suggested e-cigarette use was an efficient method for traditional smoking cessation, especially when compared to other forms of nicotine replacement therapy (NRT).20 However, there are now trends suggesting the opposite is true.21–23 Many studies have shown that e-cigarette use is associated with progression to traditional cigarette use.21–23 These findings suggest the risks and consequences of e-cigarette use may have been underestimated.
Bridging research and practice
“These findings suggest the risks and consequences of e-cigarette use may have been underestimated.”
Efforts to make meaningful change in health policy are already underway. Recent legislative initiatives, namely the Tobacco and Vapes Bill, aim to reduce e-cigarette use by restricting the advertising capacity of nicotine product manufacturers, particularly those that appeal to younger users. Equally, by taking an approach similar to that used for traditional smoking cessation, clinicians can also help reduce the prevalence and consequences of e-cigarette smoking.24
It has been shown that even minimal intervention from a doctor can encourage cessation, such as signposting, providing strategies for quitting, or explaining the associated risks.24 Intervention in this form can be implemented into almost any patient interaction.25
Counselling and follow-up, and/or NRT have been shown to be effective strategies for cessation of e-cigarette use; however, there is an overall paucity of high-quality research into this area, and therefore a lack of evidence-based interventions.26 For this reason, ongoing research is necessary to ensure clinicians can fully inform patients of the risks associated with e-cigarette use and use evidence-based approaches to achieve cessation.
It is evident that more research is needed into these areas in order to identify the risks associated with e-cigarette use and to clarify the mechanisms contributing to carcinogenicity. This information can then develop proactive guidelines for prevention, enhance clinician understanding to enable accurate public education, and inform effective e-cigarette smoking cessation practices.
References
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2. Action on Smoking and Health (ASH). Use of e-cigarettes (vapes) among adults in Great Britain. 2023. https://ash.org.uk/uploads/Use-of-e-cigarettes-among-adults-in-Great-Britain-2023.pdf (accessed 10 Jun 2025).
3. ASH. Use of vapes (e-cigarettes) among young people in Great Britain. 2024. https://ash.org.uk/uploads/Use-of-vapes-among-young-people-in-Great-Britain-2024.pdf (accessed 13 Jun 2025).
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Featured photo by Andreas Nest on Unsplash.
