Nicotine Exposure by Device Type among adult Electronic Nicotine Delivery System Users in the Population assessment of Tobacco and health Study, 2015-2016.

Introduction:
This text provides an analysis of nicotine exposure among users of open and closed system Electronic Nicotine Delivery Systems (ENDS) devices using data from the Population assessment of Tobacco and health (PaTh) Study. The study compares biomarker and survey data from Wave 3 of the PaTh study collected from October 2015 to October 2016.

Key Points:

* The study identified 277 exclusive ENDS users and 468 dual cigarette and ENDS users.
* Open system users had higher levels of total nicotine exposure (TNE-2) than closed system users among exclusive ENDS users (8.8 mmol/g creatinine vs. 2.0 mmol/g creatinine).
* however, TNE-2 concentrations were similar when open and closed system users were stratified as daily or nondaily ENDS users.
* Dual users generally had higher nicotine exposure than exclusive users, with TNE-2 concentrations of 35.3 and 40.1 mmol/g creatinine for open and closed system dual users.
* Everyday ENDS users had much higher nicotine exposure than some day users overall.
* TNE-2 levels increased with greater quantity of use for daily open system users.
* ENDS users who reported using e-liquids with nicotine had much higher nicotine exposure than users who reported that their e-liquids did not contain nicotine.
* The small number of closed system users who said that they could and did change the voltage tended to have very high TNE-2 levels.

Main Message:
The study suggests that nicotine exposure is higher among exclusive open system ENDS users compared with closed system users, but levels are similar when users are stratified by frequency of use. The results indicate that exclusive ENDS users with similar use patterns receive comparable levels of nicotine, regardless of whether they use open or closed system devices. Further investigation is needed to understand potential benefits and risks of high-nicotine electronic nicotine delivery systems to adult smokers and nicotine-naive youth.

Rostron BL, Coleman B, Cheng YC, et al. Nicotine Exposure by Device Type among adult Electronic Nicotine Delivery System Users in the Population assessment of Tobacco and health Study, 2015-2016. Cancer epidemiology, biomarkers & prevention : a publication of the american association for Cancer Research, cosponsored by the american Society of Preventive Oncology. 2020;29(10):1968-1972. doi:10.1158/1055-9965.EPI-20-0317