Preliminary data: exposure of persons aged > or = 4 years to tobacco smoke--United States, 1988-1991.

The recent report of the U.S. Environmental Protection Agency on the respiratory health effects of passive smoking (1) and the known adverse effects of active smoking emphasize the need to quantify the exposure of the U.S. population to tobacco smoke. Measurements of cotinine (a nicotine metabolite) in serum, urine, and saliva have been used effectively to quantify exposure to tobacco smoke (2-10). As part of the Third National Health and Nutrition Examination Survey (NHANES III), CDC's National Center for Environmental Health and National Center for Health Statistics is measuring serum levels of cotinine to assess exposure to tobacco smoke by persons in the United States aged > or = 4 years. This report presents preliminary findings on the first 800 persons in this survey of tobacco-smoke exposure.