This study examined overall changes in nicotine concentrations when using a popular e-cigarette and 18mg/mL nicotine e-Juice, and it further explored effects of sex and flavorings on these concentrations.Methods:
We recruited nontreatment-seeking smokers who were willing to try e-cigarettes for 2 weeks and abstain from cigarette smoking. Subjects were randomized to either menthol tobacco or non-menthol tobacco-flavored e-cigarette use for 7–10 days, and the next week they were crossed over to the other condition. On the last day of e-cigarette use of each flavor, subjects completed a laboratory session in which they used the e-cigarette for 5min ad libitum. Nicotine concentrations were obtained 5min before and 5, 10, 15, 20, and 30min after the onset of e-cigarette use.Results:
Twenty subjects completed at least 1 monitoring session. Nicotine concentrations significantly increased from baseline to 5min by 4ng/mL at the first laboratory session (p < .01) and by 5.1ng/mL at the second laboratory session (p < .01). Combining sessions, there were no main effects of sex or preferred flavor (based on smoking history) on changes in nicotine concentrations. After adding preferred flavor, sex, and visit order to the model, there was a significant preferred flavor by sex interaction (p < .01), such that women who received nonpreferred flavors had lower nicotine concentrations and rated their e-cigarette as less likeable (p < .01).Conclusion:
We found nicotine concentrations significantly increase after e-cigarette use for 5min, and flavor may impact nicotine concentrations with e-cigarette use in women.