Perceptions about levels of harmful chemicals in e‐cigarettes relative to cigarettes, and associations with relative e‐cigarette harm perceptions, e‐cigarette use and interest

Background and aims Exposure to chemicals contributes to harm from nicotine products, and e‐cigarette communications often refer to chemicals. However, while e‐cigarette studies commonly measure perceived harmfulness of e‐cigarettes relative to cigarettes, few have assessed comparative perceptions about chemicals. This study measured perceived levels of harmful chemicals in e‐cigarettes compared with cigarettes and associations with e‐cigarette/cigarette relative harm perceptions, e‐cigarette use and interest. Design, setting and participants This was an on‐line cross‐sectional survey of adults/young adults from a nationally representative research panel in the United States conducted in January 2021. Participants were independent samples of 1018 adults who smoked cigarettes and 1051 young adult non‐smokers (aged 18–29 years). Measurements Participants were asked their perceptions of the level of harmful chemicals in e‐cigarettes versus cigarettes (fewer/about the same/more/do not know), perceived harmfulness of using e‐cigarette versus cigarettes (less/about the same/more/do not know) and their current e‐cigarette use and use interest. Findings Approximately 20% of all participants (18.1% of adult smokers, and 21.0% of young adult non‐smokers) believed e‐cigarettes contain fewer harmful chemicals than cigarettes, while 35.6% of adult smokers and 24.9% of young adult non‐smokers responded ‘do not know’. Participants more frequently reported ‘do not know’ to the chemicals item than the harm item. Approximately half (51.0–55.7%) of those who believed e‐cigarettes contain fewer harmful chemicals also believed e‐cigarettes are less harmful than cigarettes. Both beliefs were associated with higher odds of interest in using e‐cigarettes [less harmful belief, odds ratio (OR) = 5.53, 95% confidence interval (CI = 2.93–10.43); fewer chemicals belief, OR = 2.45, 95% CI = 1.40–4.29] and past 30‐day e‐cigarette use (less harmful belief, OR = 2.53, 95% CI = 1.17–5.44; fewer chemicals belief, OR = 5.09, 95% CI = 2.31–11.19) for adults who smoke, but not young adult non‐smokers. Conclusions In the United States, most adults who smoke cigarettes and young adult non‐smokers do not appear to think that e‐cigarettes have fewer harmful chemicals than cigarettes, and many are uncertain about how these levels compare.