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Nicotine, Carcinogen, and Toxin Exposure in Long-Term E-Cigarette and Nicotine Replacement Therapy Users

February 7, 2017
By Lion Shahab, Maciej L. Goniewicz, Benjamin C. Blount, Jamie Brown, Ann McNeill, K. Udeni Alwis, June Feng, Lanqing Wang, and Robert West

This study examines how toxin levels in the bodies of tobacco smokers compares to toxin levels in e-cigarette and nicotine replacement therapy (NRT) users’ bodies, on a long-term basis.

two tumblers with liquor and a lit cigarrette

This study, conducted by University College London (UCL) senior lecturer in health psychology Lion Shahab and a team of UCL researchers, examines how toxin levels in the bodies of tobacco smokers compares to toxin levels in e-cigarette and nicotine replacement therapy (NRT) users’ bodies, on a long-term basis.

E-cigarette use did not increase carcinogen and toxin levels in users, Shahab writes.

“Former smokers with long-term e-cigarette-only or NRT-only use may obtain roughly similar levels of nicotine compared with smokers of combustible cigarettes only, but results varied,” Shahab writes. “Long-term NRT-only and e-cigarette–only use, but not dual use of NRTs or e-cigarettes with combustible cigarettes, is associated with substantially reduced levels of measured carcinogens and toxins relative to smoking only combustible cigarettes.

E-cigarette and NRT use is less risky than tobacco use, Shahab writes.

The lower levels of carcinogens and toxins associated with NRT-only and e-cigarette-only use in this study confirm the known low risk for complications from long-term NRT use,” Shahab writes. “This finding also underscores the translation of greatly reduced concentrations of some carcinogens and toxins from e-liquids and aerosols to body-level exposure, contrary to worries that long-term e-cigarette use would result in substantial harmful exposure.”