Summary
Introduction:
This text provides an analysis of a scientific study examining the impact of flavorings on the abuse liability of electronic cigarette (e-cigarette) liquids. The study compares the consumption, preference, and pharmacokinetics of nicotine-containing fruit- and tobacco-flavored e-liquids to nicotine alone in mouse models. The key points of the study design and major findings are summarized below.
Key Points:
* The study used adult male C57BL/6J mice and tested nicotine-containing fruit- and tobacco-flavored e-liquids, as well as nicotine-free versions of these e-liquids.
* The mice were tested in two-bottle choice tests, place conditioning assays (CPP and CPa), and nicotine pharmacokinetics experiments.
* The study found that mice showed higher consumption and preference for the fruit-flavored e-liquid compared with nicotine alone, but not for the tobacco-flavored e-liquid.
* The increased consumption and preference were not due to the flavor itself, as consumption of the nicotine-free fruit-flavored e-liquid was not elevated until the highest concentration tested.
* The place conditioning assays showed no significant differences in the CPP or CPa of the fruit-flavored e-liquid compared with nicotine, suggesting that the increased consumption and preference requires oral experience and was likely not due to altered rewarding or aversive effects of the e-liquid when administered peripherally.
* The nicotine and cotinine pharmacokinetics experiments showed no significant differences between the nicotine-containing fruit-flavored e-liquid and nicotine alone.
* The nicotine-containing tobacco-flavored e-liquid resulted in higher serum nicotine and cotinine levels compared with the nicotine-containing fruit-flavored e-liquid and nicotine alone.
Main Message:
The study suggests that certain flavors, specifically fruit flavor, may enhance nicotine consumption and preference in e-cigarette liquids. This finding has important implications for regulatory steps to limit the abuse of these products, as identifying which flavors produce this effect, the chemical composition of the flavors, and the mechanism underlying the enhancement will be crucial in determining how the abuse liability of flavored e-liquids may differ compared with nicotine alone.
Citation
Wong aL, McElroy SM, Robinson JM, et al. Flavor-specific enhancement of electronic cigarette liquid consumption and preference in mice. Drug and alcohol dependence. 2020;211:107995. doi:10.1016/j.drugalcdep.2020.107995
