Advances in the mechanistic understanding, biological consequences, and measurement of DNA adducts induced by tobacco smoke and e-cigarette aerosol: A review.

Components in tobacco smoke and electronic cigarette (e-cigarette) aerosol form adducts with DNA, which can cause DNA mutations and affect repair of DNA damage. Numerous studies have shown a strong association between inhaled smoke and lung cancer. The presence of DNA adducts can indicate chemical components of smoke. Therefore, DNA adducts are significant biomarkers of tobacco exposure that might predict lung disease status and serve as precursors to lung cancer, since they trigger DNA mutations and impair biological processes such as DNA replication and transcription. To date, no systematic review has compared tobacco smoke and e-cigarette aerosol in terms of the fate of DNA adducts. We reviewed recent studies comparing the formation of DNA adducts on exposure to components from conventional cigarette smoke versus e-cigarette aerosol. The aims of the review were threefold: (1) to summarize components of tobacco smoke and e-cigarette aerosol in relation to mechanisms for the formation of DNA adducts; (2) to highlight the biological consequences of exposure to tobacco smoke and e-cigarette aerosol; and (3) to summarize advances in understanding of the primary detection methods of DNA adducts in tobacco exposure studies. The findings of this review should benefit environmental toxicology studies of tobacco exposure.