Abstract
Background: E-cigarette designs, materials, and ingredients are continually evolving, with cotton wicks and diverse coil materials emerging as the popular components of atomisers. Another recent development is the use of nicotine salts in e-liquids to replicate the form of nicotine found in cigarette smoke, which may help cigarette smokers to transition to e-cigarettes. However, scientific understanding of the impact of such innovations on e-cigarette aerosol chemistry is limited.Methods: To address these knowledge gaps, we have conducted a comparative study analyzing relevant toxicant emissions from five e-cigarettes varying in wick, atomiser coil, and benzoic acid content and two tobacco cigarettes, quantifying 97 aerosol constituents and 84 smoke compounds, respectively. Our focus was the potential for benzoic acid in e-liquids and cotton wicks to form aerosol toxicants through thermal degradation reactions, and the potential for nickel–iron alloy coils to catalyze degradation of aerosol formers. In addition, we analyzed e-cigarette emissions for 19 flavor compounds, thermal decomposition products, and e-liquid contaminants that the FDA has recently proposed adding to the established list of Harmful and Potentially Harmful Constituents (HPHCs) in tobacco products.Results: Analyses for benzene and phenol showed no evidence of the thermal decomposition of benzoic acid in the e-cigarettes tested. Measurements of cotton decomposition products, such as carbonyls, hydrocarbons, aromatics, and PAHs, further indicated that cotton wicks can be used without thermal degradation in suitable e-cigarette designs. No evidence was found for enhanced thermal decomposition of propylene glycol or glycerol by the nickel–iron coil. Sixteen of the 19 FDA-proposed compounds were not detected in the e-cigarettes. Comparing toxicant emissions from e-cigarettes and tobacco cigarettes showed that levels of the nine WHO TobReg priority cigarette smoke toxicants were more than 99% lower in the aerosols from each of five e-cigarettes as compared with the commercial and reference cigarettes.Conclusions: Despite continuing evolution in design, components and ingredients, e-cigarettes continue to offer significantly lower toxicant exposure alternatives to cigarette smoking.
Highlights
Over the past 15 years, e-cigarettes have emerged into widespread use as credible alternatives to tobacco cigarettes
Other reviews have concluded that the absolute risks of vaping cannot yet be determined unambiguously, noting evidence for DNA damage and mutagenesis from some aerosol components (Stratton et al, 2018), adverse events in the pulmonary, oral, gastrointestinal, and other bodily systems (Seiler-Ramadas et al, 2020), dependence arising from e-cigarette use, as well as hazards from battery explosions and incidence of fatalities associated with ingestion of e-liquids
The purpose of the present study was to understand whether recent developments in e-cigarette product design influence aerosol emissions, those that may arise from use of two thermally sensitive materials: cotton and Benzoic acid (BA), and a relatively new coil material, NiFe
Summary
Over the past 15 years, e-cigarettes have emerged into widespread use as credible alternatives to tobacco cigarettes. Other reviews have concluded that the absolute risks of vaping cannot yet be determined unambiguously, noting evidence for DNA damage and mutagenesis from some aerosol components (Stratton et al, 2018), adverse events in the pulmonary, oral, gastrointestinal, and other bodily systems (Seiler-Ramadas et al, 2020), dependence arising from e-cigarette use, as well as hazards from battery explosions and incidence of fatalities associated with ingestion of e-liquids. E-cigarette designs, materials, and ingredients are continually evolving, with cotton wicks and diverse coil materials emerging as the popular components of atomisers. Another recent development is the use of nicotine salts in e-liquids to replicate the form of nicotine found in cigarette smoke, which may help cigarette smokers to transition to e-cigarettes. Scientific understanding of the impact of such innovations on e-cigarette aerosol chemistry is limited
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
