Levels of saliva cotinine in electronic cigarette users: Cotinine in vapers

Introduction:
This text is a research report on a study examining saliva cotinine levels in experienced users of electronic cigarettes, also known as "vapers." The study aimed to assess the amount of nicotine obtained by vapers and the correlation between cotinine levels and various factors, such as the number of cigarettes smoked per day before quitting smoking and the nicotine concentration in e-liquids. The key points and main message of the study are summarized below.

Key Points:

* The study was conducted as an internet survey in 2011 and 2012, with participants enrolled mainly on websites and online forums dedicated to electronic cigarettes.
* Participants were 71 users of electronic cigarettes, most of whom were former smokers and using e-cigarettes daily.
* The median concentration of nicotine in refill liquids was 16 mg/ml, and participants refilled their e-cigarette or replaced the cartridge three times per day on average.
* In the 62 e-cigarette users who, in the past 5 days, had not used any tobacco or nicotine medications, the median cotinine level was 353 ng/ml.
* The correlation between cotinine and nicotine concentration in e-liquids was r = 0.33 (P = 0.013), and the correlation between cotinine and the number of cigarettes smoked per day before quitting smoking was r = 0.48 (P < 0.001).
* In a multivariate linear regression model, only cigarettes per day before quitting (β = 6.2, P = 0.001) and nicotine concentration in e-liquids (β = 6.6, P = 0.04) were associated significantly with cotinine levels.

Main Message:
The study found that experienced users of electronic cigarettes can obtain substantial amounts of nicotine, similar to levels observed in smokers and higher than those usually observed in users of nicotine medications. These findings have important implications for the regulation of electronic cigarettes, smokers who want to quit, clinicians, and researchers. However, further assessment is needed to determine if some former smokers derive more nicotine from electronic cigarettes than they derived from tobacco cigarettes. The results of this study should be interpreted with caution due to its limitations, such as a self-selected sample and self-reports without objective verification of the use of electronic cigarettes, tobacco, and nicotine medications.

Etter, Jean-François. “Levels of Saliva Cotinine in Electronic Cigarette Users: Cotinine in Vapers.” Addiction 109, no. 5 (May 2014): 825–29. https://doi.org/10.1111/add.12475.