Nicotine content in flavored electronic cigarette liquids using three unique samples

Abstract

Background Electronic cigarette (e-cigarette) use is increasing, but consumers may be unaware of the nicotine concentrations in e-cigarettes or discrepancies in product advertised versus measured nicotine in e-cigarette liquids. Levels of nicotine, the addictive and toxic chemical in e-cigarette liquids, can influence consumers' exposure, dependence on the product, and/or success in switching from cigarettes to e-cigarettes. This study quantified the levels of nicotine in three unique samples: national sample of 147 flavored e-cigarette liquids purchased in the USA; 66 samples purchased in the state of Hawaii, USA; and 40 samples purchased in Virginia and Hawaii, USA. Methods Flavored e-cigarette liquid samples were purchased from manufacturers/distributors in 2015 for the Hawaii and Virginia samples and in 2016 for the national sample. For each flavor, staff purchased three or four concentrations of nicotine depending on manufacturer/distributor availability: 0 mg/ml; 3, 6 or 8 mg/ml; 11 or 12 mg/ml; and 18, 24 or 25 mg/ml. We measured nicotine concentration in each sample using liquid chromatography mass spectrometry and calculated the percent or relative difference for each. Results For the national sample of e-cigarette flavored liquids labeled as 0 mg/ml, 100% contained detectable levels of nicotine; 88% of Hawaii samples; and 0% of the combined Hawaii and Virginia samples in the third study. For all three unique samples, we found high levels of discordance between advertised (3 mg/ml or greater) versus measured nicotine. In some samples, levels of nicotine were higher, and in others, lower than that advertised on the labels. Discordance was not associated with flavor type. Conclusions Discrepancies between the manufacturer's labeling and measured nicotine could potentially influence nicotine delivery and toxicity exposure. Studies are needed to determine what standards are needed to ensure accurate labeling and quality controls that protect consumers, including those who are not aware that they are being exposed to nicotine.

Keywords

• WCTOH