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. 2020 Jun 4;15(6):e0234189.
doi: 10.1371/journal.pone.0234189. eCollection 2020.

Electronic nicotine delivery system design and aerosol toxicants: A systematic review

Alexandra M Ward  1 , Rola Yaman  2 , Jon O Ebbert  1
Affiliations

Electronic nicotine delivery system design and aerosol toxicants: A systematic review

Alexandra M Ward et al. PLoS One. .

Abstract

Background: Electronic nicotine delivery systems (ENDS; e-cigarettes), consisting of a battery, heating element and e-liquid, have evolved significantly with wide variation in design, components, operating powers, and chemical constituents. Generated aerosols have been reported to contain potentially toxic substances. We conducted a systematic review to assess what is known about the presence of toxicants in ENDS aerosols in order to inform how system design could mitigate risk.

Methods: Articles reporting on or evaluating design characteristics of ENDS and aerosol constituents were included and summarized.

Results: The search identified 2,305 articles, of which 92 were included after full-text review. Findings were grouped into 6 major categories of potentially harmful chemicals: carbonyls, volatile organic chemicals, trace elements, reactive oxygen species and free radicals, polycyclic aromatic hydrocarbons, and tobacco-specific nitrosamines. In general, higher concentrations of aerosol toxicants are associated with increased power or voltage. Aerosol toxicants are also associated with e-liquid flavoring agents existing as primary ingredients or as products of thermal degradation.

Conclusions: Improved ENDS design can reduce toxicant levels. Additional research is needed to develop a framework for optimizing system characteristics to minimize exposure, especially with respect to heating power and e-liquids. Both manufacturers and regulatory agencies have roles in reducing toxicants and potential health risks from ENDS.

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Conflict of interest statement

This work is made possible by the generosity of HH Sheikh Hamed Bin Zayed Al Nahyan. The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. JOE declares that he has received consulting fees and is a shareholder in Nesmah. The authors have no other conflicts of interest to declare. This does not alter our adherence to PLOS ONE policies on sharing data and materials.

Figures

Fig 1
Fig 1. Methodological approach for systematic review and article selection.
See this image and copyright information in PMC

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