Perceptions and impacts of e-cigarettes

The primary function of e-cigarettes is to deliver nicotine, as with tobacco cigarettes and nicotine replacement products you can buy in a pharmacy.

Smokers are not addicted to tobacco: they are addicted to nicotine. Most smokers continue to smoke despite wanting to quit because nicotine is a remarkably addictive drug. However, smokers don’t die from exposure to nicotine. It’s the cocktail of other chemicals that is produced when tobacco is burnt that does the harm. E-cigarettes and nicotine replacement therapy products, such as gum, lozenges, patches and sprays, offer alternative ways of getting nicotine into your body without having to inhale tobacco smoke.

The following are key differences between tobacco cigarettes and e-cigarettes, in the context of their regulation in the UK:

• Tobacco has been smoked in Britain for over 400 years and the survival of cigarettes and other tobacco products in today’s regulated market is a historical anomaly. It would be impossible to bring a product as toxic as a cigarette to market today. The regulation of tobacco products is not therefore focused on their content – which is unavoidably toxic – but on their advertising, display, packaging and use.
• Nicotine replacement therapy (NRT) products are licensed medicines, designed to help people quit smoking. NRT products deliver nicotine without all the toxic chemicals that are produced when tobacco is burnt. Nicotine itself is relatively safe, though highly addictive. NRT products have to be rigorously tested for safety in order to get a licence as a medicine from the Medicines and Healthcare products Regulatory Agency (MHRA). Smokers who use NRT to quit smoking may in time also stop using NRT; others continue to use NRT to meet their need for nicotine.
• E-cigarettes have similar characteristics to both cigarettes and NRT products. Like tobacco cigarettes, they deliver nicotine via inhalation: they are designed to mimic the experience of smoking. Like NRT products, they deliver nicotine without the tar and toxic chemicals that smokers inhale. However, unlike NRT products, they are not medicines, or at least none of the products currently on the market in Britain have been licensed as medicines.

E-cigarettes are overwhelmingly used by ex-smokers and current smokers. It is estimated that there are over 3.6 million adults in Great Britain using e-cigarettes – 7.1% of the adult population. Of these e-cigarette users , 64.6% of current vapers were ex-smokers, while 30.5% also smoked (dual users). The proportion of adult smokers who have tried e-cigarettes has continued to grow, while those who have never tried continues to decline.

People use e-cigarettes for a variety of reasons. The vast majority for health reasons, to help them quit, prevent relapse or cut down the amount they smoke. Vapers also report using e-cigarettes to save money compared to smoking, to protect others from second-hand smoke and because it gives them pleasure.

E-cigarette users also have diverse attitudes to their vaping. Some perceive their use of e-cigarettes as a way of managing their nicotine addiction and keeping off cigarettes; others think of vaping simply as a pleasure which they intend to enjoy in the long term. A third group, who are likely still to smoke, feel ambivalent about their e-cigarette use and do not think of themselves as ‘vapers’.

Vaping an e-cigarette is much less harmful than smoking a tobacco cigarette because tobacco smoke is not inhaled. Most of the toxins in tobacco smoke are not found in the vapour of e-cigarettes and those that are present are at much lower levels – mostly below 1%.

The active ingredient of e-cigarettes is nicotine. Nicotine, when inhaled in smoke, is a highly addictive drug, which absorbs the time, money and attention of its users. But long-term use of nicotine consumed through NRT has not been found to increase the risk of serious health problems. A review of the efficacy and safety of NRT in pregnancy found that NRT increased smoking cessation rates, measured in late pregnancy, by approximately 40%. The authors found no evidence that NRT used for smoking cessation in pregnancy has either positive or negative impacts on birth outcomes.

There are some health risks associated with the other ingredients of e-cigarettes, but they are low compared to tobacco products. In particular:

• Propylene glycol and glycerine, components of e-liquids, can produce toxic aldehydes if they are overheated. Fortunately overheating also creates a bad taste that puts off the user. At normal vaping temperatures, the quantity of aldehydes produced is only a small fraction of the levels inhaled by smokers.
• Flavourings could pose a risk to health but there is currently no evidence that any flavourings used by e-cigarette manufacturers present a significant risk to their users.
• Metals have been identified in e-cigarette vapour but at concentrations so low that their risk to health is minimal.

E-cigarette users can sometimes generate large clouds of vapour which to bystanders may look as troublesome as a cloud of cigarette smoke. Yet to date no risks have been identified of ‘passive vaping’.

As the risk to vapers of inhaling e-cigarette vapour is low, the risk to those who breathe their exhaled vapour is even lower: concentrations of vaping-related chemicals are simply too low to have any impact. Furthermore, most secondhand tobacco smoke comes from the burning tip of the cigarette, not the smoker, but there is no such ‘sidestream’ vapour produced by e-cigarette users.

Vaping is positively associated with quitting smoking successfully. Findings from a recent report commissioned by Public Health England, (PHE) demonstrated that e-cigarettes are the most popular aid used in quit attempts. 27.2% of people used a vaping product in a quit attempt in the previous 12 months, compared with 15.5% who used NRT over the counter or on prescription (2.7%) and 4.4% who used varenicline. More than half (64%) of the e-cigarette users in Great Britain were ex-smokers. Among all ex-smokers, nearly one in ten (9.5%) regularly used e-cigarettes. It is abundantly clear that e-cigarettes have played, and continue to play, an important role in helping people quit smoking and stay smokefree.

The use of e-cigarettes by smokers who want to quit smoking increases their chance of success. A major UK clinical trial published  found that, when combined with expert face-to-face support, people who used e-cigarettes to quit smoking were twice as likely to succeed as people who used other nicotine replacement products, such as patches or gum. The National Institute for Health and Care Excellence (NICE) has, for the first time, included vaping products, also known as electronic cigarettes, as a recommended stop smoking aid in its newly released tobacco guidelines. The guidelines mean that alongside providing clear and up-to-date information about vaping products, stop smoking services should also make these products accessible to adults who want to use them to quit. The most recent guidance for health professionals from the National Institute for Health and Care Excellence (NICE) is available online.

To date, there is no evidence that significant numbers of non-smokers are experimenting with e-cigarettes and subsequently becoming smokers. E-cigarettes have proved to be an important gateway out of smoking, not into it. The behaviour of young people has been a particular concern. However, analysis of data from the  ASH YouGov Smokefree youth GB survey suggests that while some young people experiment with e-cigarettes, particularly those who have tried smoking, regular use remains low. Furthermore, the prevalence of regular e-cigarette use by young people who had never smoked was negligible (between 0.1% and 0.5%). Overall, there is no evidence that e-cigarettes have driven up smoking prevalence in this age group. In fact, smoking prevalence among young people has declined since e-cigarettes came onto the market. However, continued surveillance is needed.