E-cigarettes – revisited

Since our last update about nicotine-containing e-cigarettes, there has been an explosion of research published and a variety of steps taken by governments. Today’s brief provides a quick summary of a few of those findings and activities.

In the past 18 months, several hundred research papers have been published, with some interesting work focused on use of e-cigarettes as smoking cessation aids. One report of particular interest was a cross-sectional population study of 5,863 adult smokers who had the intention to quit, which revealed that e-cigarette users were more likely to report continued abstinence than the users of either nicotine replacement therapies or other smoking cessation aids.¹ Another prospective controlled randomized clinical trial in a sample of smokers who were not intending to quit, indicated levels of smoking reduction and abstinence resulting from the replacement of cigarettes with e-cigarettes.² These findings can be contrasted with the results of the 2011–2013 US National Youth Tobacco Survey of students in grades 6–12 who had never smoked, the latter survey showing that the intention to use traditional cigarettes was higher among e-cigarette users than among those who never used e-cigarettes;³ another recent population-based study from California cautions that smokers who used e-cigarettes might be at higher risk of not quitting smoking.⁴ Clearly, more work is required to understand these complex relationships. More information on e-cigarette consumption in Canada has also become available through the 2013 Canadian Tobacco, Alcohol and Drugs Survey (CTADS). These data show that 2.5 million Canadians aged 15 and older (9%) have tried an e-cigarette, while 20% of youth aged 15-19 and 20-24 have tried them.⁵

There have also been a number of research studies that looked at the possible toxic effects of e-cigarette liquids and aerosols. One of these studies has shown very low in vitro cytotoxicity,⁶ while another has shown adverse physiological effects after short-term in vivo exposure.⁷ This work is still in its infancy; as such, it is too early to develop conclusions regarding possible long-term effects. In order to achieve a balanced perspective, these data should also be compared to data on the effects of cigarette smoking.

Some of the most interesting changes have come on the political landscape. In an effort to respond to the increasing popularity of e-cigarettes in Canada, provincial health authorities in Ontario, British Columbia, Nova Scotia and Quebec have established restrictions on e-cigarettes.^8-10 Their legislations place e-cigarettes under provincial Tobacco Acts, subjecting them to prohibitions on use in public places and placing limitations on the age requirement for sales and marketing.^9-12

Two interesting reports from federal governments in different countries have been published. The first is the House of Commons’ Standing Committee on Health, Environment and Social Affairs (HESA) report on their review of e-cigarettes in Canada.¹³ It summarized the findings from a series of hearings that sought the opinion of a cross-section of stakeholders, including CPHA. This report, released in March, called for a new legislative framework for nicotine- and non-nicotine-containing e-cigarettes that would prohibit their use in federally regulated public spaces; restrict promotional and marketing activities; disclose information related to ingredients; place an age limit on purchasers; and ensure that the products are visually distinct.¹³ The second is a recent report by Public Health England (PHE) endorsing the potential of e-cigarettes as a smoking cessation aid.¹⁴ That report emphasized that the adult and youth smoking rates in England have steadily declined over the years, while e-cigarettes became the most popular cessation aid: their use has risen sharply over the last 5 years in England and they are now used by approximately 35% of those trying to quit. PHE’s prediction, therefore, is that nicotine-containing e-cigarettes will significantly contribute to achieving the department of health’s goal of a tobacco-free generation by 2025.¹⁴

E-cigarettes continue to be a challenging public health issue. Effective policy and legislation continue to be hindered by a lack of integrated evidence to support decision-making, as well as a tendency to equate e-cigarettes with cigarettes. Moreover, novel control strategies, including the notion of differential taxation on all nicotine-containing products, based on their relative harmfulness, should be considered as an approach to better regulating nicotine-containing e-cigarettes.¹⁵