Changes in Biomarkers of Cigarette Smoke Exposure after 6 Days of Switching Exclusively or Partially to Use of the JUUL System with Two Nicotine Concentrations: a Randomized Controlled Confinement Study in adult Smokers.

Introduction:
This article is a scientific study examining the effects of using the JUUL electronic nicotine delivery system (ENDS) on biomarkers of exposure (BOEs) to harmful tobacco smoke constituents in adult smokers. The study compares changes in BOEs among smokers who completely switched to JUUL, those who continued to smoke their usual brand cigarettes, those who abstained from all tobacco and nicotine product use, and those who used JUUL and continued smoking but reduced their cigarette consumption by at least 50% (dual users). The study also examines the impact of JUUL nicotine concentration and flavor on BOEs.

Key points:

* The study was a randomized, open-label, parallel-group trial conducted in a residential laboratory setting over six days.
* Participants were healthy adult smokers aged 21-65 years who smoked at least 10 manufactured cigarettes per day for at least 12 months.
* Participants were randomized into 11 study groups, including eight groups exclusively using JUUL in four flavors and two nicotine concentrations, one dual-use group, one usual brand cigarette group, and one abstinence group.
* BOEs assessed included total NNaL, 3-hPMa, MhBMa, S-PMa, COhb, NNN, hMPMa, CEMa, 1-OhP, O-Tol, 2-Na, and 4-aBP.
* The study found that:
+ Median reductions in primary BOEs in JUUL groups were 90%-≥100% of abstinence, and there were no significant differences between JUUL groups and abstinence.
+ all reductions in JUUL groups were substantially and statistically significantly greater than reductions in the UB Cigarette group (ps < 0.025).
+ Median reductions in primary BOEs in the Dual-Use group were 43%-55% of abstinence.
+ Similar results were observed for secondary BOEs.
+ There were minimal differences in exposure to non-nicotine BOEs by flavor (Virginia Tobacco, Menthol, Mint, Mango) or JUUL nicotine concentration (5.0% vs. 3.0%).
* The study was funded by Juul Labs, Inc., the manufacturer of the JUUL System, and the authors declare conflicts of interest.

Main message:
The study suggests that the use of JUUL as a complete or partial substitute for combustible cigarettes can substantially reduce exposure to multiple toxins associated with cigarette smoking. The study adds to the growing body of evidence supporting the utility of ENDS products as potentially reduced-harm alternatives to cigarettes for adult smokers. however, long-term studies are needed to confirm the benefits of JUUL and other ENDS products in reducing tobacco-related harm.

Cohen G, Goldenson NI, Bailey PC, Chan S, Shiffman S. Changes in Biomarkers of Cigarette Smoke Exposure after 6 Days of Switching Exclusively or Partially to Use of the JUUL System with Two Nicotine Concentrations: a Randomized Controlled Confinement Study in adult Smokers. Nicotine & tobacco research : official journal of the Society for Research on Nicotine and Tobacco. 2021;23(12):2153-2161. doi:10.1093/ntr/ntab134