Electronic cigarettes (e-cigarettes) have been labeled a disruptive technology resulting in much speculation as to whether they are likely to help or hinder efforts to reduce tobacco-related morbidity and mortality. Awareness of e-cigarettes has increased dramatically and public perceptions of their harmfulness vary (HINTS brief no. 28, February 2015). E-cigarette adoption has far outpaced knowledge of the actual harms and benefits, making informed discussion difficult for consumers, clinicians, and scientists alike.
What are E-Cigarettes?
E-cigarettes are a type of non-combustible, electronic nicotine delivery system (ENDS) that delivers aerosolized nicotine often called vapor. The nicotine in e-cigarettes comes in the form of a liquid made of nicotine, water, and a propellant (propylene glycol and/or glycerin) plus other chemical constituents like flavors. With the caveat that these products are currently unregulated and manufacturing varies, e-cigarette vapor contains no known carcinogens and fewer toxicants than cigarette smoke.
Friend or Foe?
E-cigarettes have been touted as a way to make combustible tobacco products obsolete either by helping smokers to quit or by replacing conventional cigarettes. Although far from definitive, the research available to date demonstrates promise for e-cigarettes in harm reduction. One randomized trial compared e-cigarettes to nicotine replacement therapy and found no difference in quitting outcomes. However, the relevance of these early trials and observational research, which studied first- and second-generation devices, is unclear in today’s market which includes third- and fourth-generation e-cigarettes, e-hookahs, and personal tank-style vaporizers which can deliver higher concentrations of nicotine. More research is needed to examine whether e-cigarettes can safely help more smokers than currently available cessation medications. If smokers who are unable to quit switched to e-cigarettes, this could also be a path toward eliminating tobacco-related illness. On the other hand, most e-cigarette users are dual users, meaning that they use both e-cigarettes and traditional cigarettes together. Replacing some but not all cigarettes with e-cigarettes may not yield measurable health benefits. From a public health perspective, opponents of e-cigarettes worry that normalizing smoking behavior could undo the progress achieved by decades of anti-smoking efforts like advertising bans and smoke-free laws. The strongest argument against e-cigarettes comes from concern over uptake among youth. Delivery of nicotine from e-cigarettes may harm the developing brain directly or serve as a gateway to further tobacco use.
Further studies are needed to understand the potential risks and benefits of e-cigarettes. Federal regulation and defining a clear research agenda, such as that recommended jointly by the American Association for Cancer Research and the American Society of Clinical Oncology (Brandon et al. 2015), are key steps toward understanding the promise or peril of e-cigarettes.