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Impact of vaping introduction on cigarette smoking in six jurisdictions with varied regulatory approaches to vaping: an interrupted time series analysis
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  • Published on:
    Incorrect classification of vaping regulations

    The potential impact of e-cigarette use on smoking prevalence is an important public health question. The Wu et al. paper examines this question by comparing changes in smoking prevalence across three jurisdictions with different e-cigarette regulations: Canada, the UK, and Australia.

    The paper concludes that cigarette consumption and smoking prevalence decreased to a greater extent in jurisdictions with less restrictive e-cigarette regulations. This would be a noteworthy finding; however, the paper suffers from a fundamental flaw in terms of how jurisdictions have been categorized. Canada is coded as the ‘least restrictive’ regulatory environment, the UK as ‘more restrictive’, and Australia as ‘most restrictive’, on the basis that no nicotine-containing e-cigarettes were legal for sale in Australia. The authors appear to be unaware that, prior to a legislative change in 2018, nicotine-containing e-cigarettes were not legal for sale in Canada.1,2 Thus, during the period examined in the study (2012 to 2018), Canada had the most restrictive vaping regulations possible, which were materially no different than Australia. In contrast, the UK is widely regarded as having one of the least restrictive markets for e-cigarettes in the world: while nicotine-containing e-cigarettes were prohibited in Canada and Australia, in the UK e-cigarettes were legally sold and marketed in a wide variety of retail locations, and government agencies officially endorsed the harm reduction p...

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    Conflict of Interest:
    None declared.
  • Published on:
    A bewildering study with a head-scratching analysis

    This paper attempts to assess the impact of vaping regulations on tobacco use, using the natural experiment of differing regulatory approaches in Canadian provinces and in other countries. The regulatory distinctions explored are maximum nicotine concentration (characterized as maximum permissible nicotine), minimum age for purchase and sales, and restrictions on marketing, and advertisement.

    What makes the study design bewildering is the choice of a time period for analysis (2012-2018) that predates the legal sale of e-cigarettes in Canada. Nicotine vaping products were not legal for sale in Canada until the Tobacco and Vaping Products Act (TVPA) came into force in May 2018. Prior to this time, inhalable nicotine was regulated under the Food and Drugs Act, which required manufacturers to demonstrate safety, quality and efficacy before being authorized to sell their products. (1) Because no manufacturers had done so, e-cigarettes were illegal for sale in Canada for 6 of the 7 years of this study.

    The paper states that during the study period the maximum nicotine in Canada was 66 mg/ml. There was no maximum level on nicotine concentration until July 2020, when the level was set at 66 mg/ml (2), before being reduced to 20 mg/ml a year later (3). That is, for almost all of the period of the study (until May 2018), the maximum nicotine concentration was 0 mg/ml, and during the last 7 months of the study period (May to December 2018) there was no maximum limit...

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    Conflict of Interest:
    None declared.