Purpose: This study assesses the validity of hair nicotine as a biomarker for secondhand smoke (SHS) exposure. Although most biomarkers of tobacco-smoke exposure have a relatively short half-life, hair nicotine can measure several months of cumulative SHS exposure. Design: A cross-sectional study of hospitality-industry workers. Method: Hair samples were obtained from 207 bar and restaurant workers and analyzed by the reversed-phase high-performance liquid chromatography with electrochemical detection (HPLC-ECD) method. Self-reported tobacco use and sources of SHS exposure were assessed. Findings: Higher hair-nicotine levels were associated with more cigarettes smoked per day among smokers and a greater number of SHS-exposure sources among nonsmokers. Number of SHS exposure sources, gender, number of cigarettes smoked per day, and type of establishment predicted hair-nicotine levels. Discussion: Hair nicotine is a valid measure of SHS exposure. It may be used as an alternative biomarker to measure longer term SHS exposure.
Secondhand tobacco smoke exposure of infants at home: A population based cross-sectional study
