Key Words Environmental tobacco smoke (ETS) Nicotine

Diffusion monitor Indoor air nicotine concentrations in the homes of young children (ages 1-3 years) were monitored for 48 h as part of a study to assess uptake, metabolism and urinary excretion of nicotine and its metabolites, including cotinine. Cotinine has been used as a biological marker for personal exposure to envi-ronmental tobacco smoke (ETS). The evaluation of the utility of cotinine as a biomarker of exposure to ETS depends upon an accurate measure of the nico-tine exposure. Personal exposure to nicotine was monitored using a passive diffusion monitor worn by the children. Identical-type stationary monitors were also placed in each home to measure indoor nicotine for comparison to personal monitors. Home and personal monitoring were conducted for a 48-hour period proceeding admittance of the children into a hospital clinical unit where smoking was prohibited. Personal monitors were also utilized to deter-mine personal exposure to nicotine in the clinical unit. A total of 42 childre