Self-Reported Use of Tobacco, E-cigarettes, and Marijuana Versus Urinary Biomarkers.

Background: Surveys have been instrumental in describing adolescent use of tobacco, electronic cigarettes (e-cigarettes), and marijuana. However, objective biomarker data are lacking. We compared adolescent self-reported use to urinary biomarkers.
Methods: From April 2017 to April 2018, adolescents 12 to 21 years old completed an anonymous questionnaire regarding tobacco, e-cigarette, and marijuana use and provided a urine sample. Urine was analyzed for biomarkers cotinine, total 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol, and tetrahydrocannabinolic acid (THCA).
Results: Of 517 participants, 2.9% reported using tobacco, 14.3% e-cigarettes, and 11.4% marijuana in the past week. Only 2% reporting no smoking had total 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol levels above cutoff (14.5 pg/mL); 2% of non-e-cigarette users had cotinine above cutoff (10 ng/mL); 2% of those denying marijuana use had THCA above cutoff (10 ng/mL). Daily e-cigarette users showed significantly higher median cotinine than nondaily users (315.4 [interquartile range (IQR) 1375.9] vs 1.69 ng/mL [IQR 28.2]; P < .003). Overall, 40% who reported using nicotine-free products had cotinine >10 ng/mL. Pod users' median cotinine was significantly higher than in nonpod users (259.03 [IQR 1267.69] vs 1.61 ng/mL [IQR 16.3]; P < .003). Median THCA among daily marijuana users was higher than in nondaily users (560.1 [IQR 1248.3] vs 7.2 ng/mL [IQR 254.9]; P = .04). Sixty-one percent of those with cotinine >10 ng/mL vs 39% of those with cotinine<10 ng/mL had THCA >10 ng/mL ( P < .001).
Conclusions: Adolescents' self-report correlated with measured urinary biomarkers, but subjects were unaware of their nicotine exposure. More frequent e-cigarette and pod use correlated with elevated biomarkers. Co-use of tobacco, e-cigarettes, and marijuana was corroborated by higher THCA in those with higher cotinine.
Competing Interests: POTENTIAL CONFLICT OF INTEREST: Dr Goniewicz received a research grant from Pfizer and served as an advisory board member to Johnson & Johnson, pharmaceutical companies that manufacture smoking cessation medications. Additionally, Dr Goniewicz was a member of the National Academies of Sciences, Engineering, and Medicine Committee on the Review of the Health Effects of Electronic Nicotine Delivery Systems, which wrote the report; the report was funded by the US Food and Drug Administration, but the US Food and Drug Administration was not involved in the drafting or review of the National Academies of Sciences, Engineering, and Medicine report or this manuscript. The policy implications written in this article are the views of the authors and do not necessarily represent the views of the other members of the committee; the National Academies of Sciences, Engineering, and Medicine; or the US Food and Drug Administration; the other authors have indicated they have no potential conflicts of interest to disclose.
(Copyright © 2019 by the American Academy of Pediatrics.)