E-cigarette use among adolescents has increased rapidly in recent years. One of the arguments that proponents of e-cigarettes have made is that e-cigarettes are potentially safer than combustible cigarettes.
One of the major components of e-cigarettes is nicotine, and it is unclear what the nicotine exposure from e-cigarettes is in adolescents. Pediatrics is early releasing an article that looks at this question.
In the article, entitled “Biomarker Assessment of Nicotine Exposure among Adolescent E-cigarette Users: 2018–2019,” Hongying Daisy Dai, PhD, and colleagues at the University of Nebraska and Kansas City University present data from the national Population Assessment of Tobacco and Health (PATH) study of 13–17 year olds in 2018–2019 (10.1542/peds.2023-062424). Approximately 1300 participants answered surveys and submitted a urine sample. Urine samples were tested for 2 nicotine metabolites—cotinine and trans-3’-hydroxycotinine (3-HC). To correct for urine concentration, the authors present their results in cotinine:creatinine ratios (ng/mg creatinine).
The results are quite telling:
- Compared to non-users, users of both non-nicotine-containing and nicotine-containing e-cigarettes had urinary cotinine levels that were very high—12 times and 146 times higher, respectively!
- Levels of cotinine and 3-HC increased with higher vaping frequency. For instance, mean cotinine levels were 10.1 ng/mg creatinine for occasional users, 73.6 ng/mg creatinine for intermittent users, and 949 ng/mg creatinine for frequent users.
- There were no differences by flavor type.
For comparison purposes, for users of combustible cigarettes, urine cotinine concentrations generally range from 10 to >500 ng/ml, which, when the conversion factor is used to account for creatinine levels, is equivalent to a range of 9 to >450 ng/mg creatinine.
Why did users of non-nicotine-containing e-cigarettes have high cotinine levels? While it’s not entirely clear, the authors speculate that either the users didn’t know that the product they were vaping had nicotine in it—or the product was mislabeled—or that this is the result of secondhand nicotine exposure from being with friends and family members who are using either nicotine-containing e-cigarettes or combustible cigarettes.
The takeaway message from this article is that nicotine levels in e-cigarette users are equivalent or higher than those in traditional smokers. This can be important information to share with your adolescent and young adult patients who are vaping.
