Monitoring absorption by means of determination of nicotine and cotinine.

Recent studies indicate that nonsmokers exposed to environmental tobacco smoke (ETS) acquire an impaired lung function and run an increased risk of lung cancer. These findings have been questioned mainly on the basis that the amount of ETS received by the nonsmoker has remained unquantified. The factural risk of ETS exposure could possibly be estimated by measuring the absorption of tobacco smoke products by nonsmokers. Nicotine, which is specific to tobacco, and its main metabolite, cotinine, have been used for this purpose. The usefulness of these markers based on data obtained for different body fluids from nonsmokers exposed to ETS under experimental as well as field conditions is discussed.