Introduction The Tobacco Control Act requires public disclosure of information about toxic constituents in cigarette smoke. To inform these efforts, we studied public understanding of cigarette smoke constituents. Methods We conducted phone surveys with national probability samples of adolescents (n=1125) and adults (n=5014) and an internet survey with a convenience sample of adults (n=4137), all in the USA. We assessed understanding of cigarette smoke constituents in general and of 24 specific constituents. Results Respondents commonly and incorrectly believed that harmful chemicals in cigarette smoke mostly originate in additives introduced by cigarette manufacturers (43–72%). Almost all participants had heard that nicotine is in cigarette smoke, and many had also heard about carbon monoxide, ammonia, arsenic and formaldehyde. Less than one-quarter had heard of most other listed constituents being in cigarette smoke. Constituents most likely to discourage respondents from wanting to smoke were ammonia, arsenic, formaldehyde, hydrogen cyanide, lead and uranium. Respondents more often reported being discouraged by constituents that they had heard are in cigarette smoke (all p<0.05). Constituents with names that started with a number or ended in ‘ene’ or ‘ine’ were less likely to discourage people from wanting to smoke (all p<0.05). Discussion Many people were unaware that burning the cigarette is the primary source of toxic constituents in cigarette smoke. Constituents that may most discourage cigarette smoking have familiar names, like arsenic and formaldehyde and do not start with a number or end in ene/ine. Our findings may help campaign designers develop constituent messages that discourage smoking.

Background Interventionists commonly identify promising messages for health communication efforts based on audience members’ ratings of perceived message effectiveness (PME). Purpose We sought to validate a new PME measure that improved on existing scales by focusing on the behavior and respondent, being brief, and having strong psychometric properties. Methods Participants were a national convenience sample of 999 adults and national probability samples of 1,692 adults and 869 adolescents recruited in 2015. Smokers and nonsmokers rated up to six brief messages about the chemicals in cigarette smoke on two PME scales. The first was the new three-item University of North Carolina (UNC) PME Scale that assessed effects perceptions. The second was an established six-item PME scale that assessed message perceptions. We examined the UNC PME Scale’s psychometric properties and compared both scales using item factor analysis. Results The UNC PME Scale measured the same construct across multiple chemical messages (all factor loadings ≥ 0.86). It exhibited high reliability (>0.85) over very low to moderate levels of PME (z = −2.5 to 0.2), a range that is useful for identifying more promising messages. Samples of adults and adolescents showed a similar pattern of results. As expected, the UNC PME Scale was strongly positively correlated with message perceptions (r = .84). It also exhibited strong psychometric properties among participants regardless of education, reactance, sex, and smoking status. Discussion The UNC PME Scale reliably and validly measured PME among adults and adolescents from diverse groups. This brief scale may be used to efficiently evaluate candidate antismoking messages and may be suitable for adaptation to other health risk behaviors.

Laws and treaties compel countries to inform the public about harmful chemicals (constituents) in cigarette smoke. To encourage relevant research by behavioral scientists, we provide a primer on cigarette smoke toxicology and summarize research on how the public thinks about cigarette smoke chemicals. We systematically searched PubMed in July 2016 and reviewed citations from included articles. Four central findings emerged across 46 articles that met inclusion criteria. First, people were familiar with very few chemicals in cigarette smoke. Second, people knew little about cigarette additives, assumed harmful chemicals are added during manufacturing, and perceived cigarettes without additives to be less harmful. Third, people wanted more information about constituents. Finally, well-presented chemical information increased knowledge and awareness and may change behavior. This research area is in urgent need of behavioral science. Future research should investigate whether educating the public about these chemicals increases risk perceptions and quitting.

BackgroundA prevailing hypothesis is that health warnings for electronic cigarettes (e-cigarettes) could drive people away from vaping and towards smoking cigarettes. We consider an alternative hypothesis that e-cigarette warnings discourage both vaping and smoking.MethodsParticipants were a national convenience sample of 2218 US adults who used e-cigarettes, cigarettes or both. In August 2018, we randomised participants to one of three warning types (control text about littering, text-only e-cigarette warning or pictorial e-cigarette warning). We further randomised participants viewing e-cigarette warnings to one of three topics (nicotine addiction, health hazards of use, or both health hazards and harms of use). The preregistered primary outcome was intentions to quit vaping among e-cigarette users. Secondary outcomes included interest in smoking and Tobacco Warnings Model constructs: attention, negative affect, anticipated social interactions and cognitive elaboration.ResultsText warnings elicited higher intentions to quit vaping than control among e-cigarette users (d=0.44, p<0.001), and pictorial warnings elicited still higher intentions to quit vaping than text (d=0.12, p<0.05). Text warnings elicited lower interest in smoking compared with control among smokers (p<0.05); warnings had no other effects on interest in smoking among smokers or non-smokers. Text warnings about health hazards elicited higher intentions to quit vaping than nicotine addiction warnings. E-cigarette warnings also increased Tobacco Warnings Model constructs.DiscussionE-cigarette health warnings may motivate users to quit vaping and discourage smoking. The most promising warnings include health hazards (other than nicotine addiction) and imagery. We found no support for the hypothesis that e-cigarette warnings could encourage smoking cigarettes.

ObjectiveUnder US law, tobacco product marketing may claim lower exposure to chemicals, or lower risk of health harms, only if these claims do not mislead the public. We sought to examine the impact of such marketing claims about potential modified risk tobacco products (MRTPs).MethodsParticipants were national samples of 4797 adults and 969 adolescent US smokers and non-smokers. We provided information about a potential MRTP (heated tobacco product, electronic cigarette or snus). Experiment 1 stated that the MRTP was as harmful as cigarettes or less harmful (lower risk claim). Experiment 2 stated that the MRTP exposed users to a similar quantity of harmful chemicals as cigarettes or to fewer chemicals (lower exposure claim).ResultsClaiming lower risk led to lower perceived quantity of chemicals and lower perceived risk among adults and adolescents (all p<0.05, Experiment 1). Among adults, this claim led to higher susceptibility to using the MRTP (p<0.05). Claiming lower exposure led to lower perceived chemical quantity and lower perceived risk (all p<0.05), but had no effect on use susceptibility (Experiment 2). Participants thought that snus exposed users to more chemicals and was less safe to use than heated tobacco products or electronic cigarette MRTPs (Experiments 1 and 2).DiscussionRisk and exposure claims acted similarly on MRTP beliefs. Lower exposure claims misled the public to perceive lower perceived risk even though no lower risk claim was explicitly made, which is impermissible under US law.