A comparison of methods of assessing exposure to environmental tobacco smoke in non-smoking British women

Fifty-two non-smoking British women were recruited to wear personal monitors for nicotine and volatile organic compounds over a 24-h period in the autumn of 1989. The subjects also supplied samples of saliva for cotinine analysis, and answered questions regarding lifestyle and exposure to environmental tobacco smoke (ETS). The research indicates that exposure to ETS in free-living subjects is very low (mean nicotine exposure 2.3 μg m 3). Moreover, the greatest influence on exposure was living with a smoker, contact with smokers at work; leisure or travel having a minor impact. Salivary cotinine levels were found in subjects observed not to be exposed to ETS, hence somewhat questioning the validity of this measure for very low levels of exposure. Both of the objective measures of ETS exposure, nicotine and salivary cotinine levels, only correlated modestly with subjective assessments of exposure obtained by questionnaire.