Background: Menthol cigarettes are smoked by 27% of U.S. smokers, and there are concerns that menthol might enhance toxicity of cigarette smoking by increasing systemic absorption of smoke toxins. We measured urine menthol concentrations in relation to biomarkers of exposure to nicotine and tobacco carcinogens. Methods: Concentrations of menthol glucuronide (using a novel analytical method), nicotine plus metabolites (nicotine equivalents, NE), 4-(methylnitrosamino)-1-(3)pyridyl-1-butanol (NNAL) and polycyclic aromatic hydrocarbon (PAH) metabolites were measured in the urine of 60 menthol and 67 regular cigarette smokers. Results: Urine menthol was measurable in 82% of menthol and 54% in regular cigarette smokers. Among menthol smokers urine menthol was highly correlated with NE, NNAL and PAHs. In a multiple regression model NE but not menthol was significantly associated with NNAL and PAHs. Conclusions: Urine menthol concentration is a novel biomarker of exposure in menthol cigarette smokers, and is highly correlated with exposure to nicotine and carcinogens. Menthol is not independently associated with carcinogen exposure when nicotine intake is considered. Impact: Reconsidering menthol's role in enhancing toxicity of cigarette smoking by increasing systemic absorption of smoke toxins.
- Received July 1, 2010.
- Revision received September 9, 2010.
- Accepted October 11, 2010.