E-Cigarettes: Formaldehyde DNA Adducts, Oxidative Damage, and Potential Toxicity and Carcinogenesis
Principal Investigator: Stephen S. Hecht
Funding Mechanism: National Institutes of Health - Grant
ID number: 1R01CA203851-01A1
Award Date: 2/21/2017
Institution: University of Minnesota
Recent reports indicate that e-cigarettes may generate unacceptable levels of the human carcinogen formaldehyde, and preliminary data indicate that levels of urinary biomarkers of oxidative damage and inflammation are the same in e-cigarette users as in cigarette smokers. The goal of this study is to test whether e-cigarette use leads to formaldehyde-DNA adducts and elevated exposure to other carbonyls, and to similar levels of oxidative damage and inflammation as in smokers; the study will also assess toxicant and carcinogen exposure in e-cigarette users, smokers, and non-smokers. Specific aims are: (1) to quantify formaldehyde-DNA adducts in tissues of rats exposed to vapor generated from e-liquids containing propylene glycol; (2) to analyze samples from a prior study in which smokers stopped smoking for 12 weeks to determine the time course of decreases in formaldehyde-DNA adducts in leukocytes and 8-iso-PGF-2α and prostaglandin E2 metabolite (PGEM) in urine; and (3) to recruit 134 e-cigarette tank system users, 134 smokers, and 134 non-users of any e-cigarette or tobacco product and compare levels of (a) formaldehyde, diacetyl, and other carbonyl compounds in saliva (before and after puffing in the e-cigarette users and smokers), (b) formaldehyde-DNA adducts in oral cells and leukocytes, (c) 8-iso-PGF-2α and PGEM in urine, (d) C-reactive protein, the serum biomarker of inflammation, and (3) a panel of urinary toxicant and carcinogen biomarkers.