Secondhand tobacco smoke exposure among children and adolescents: United States, 2003-2006.

OBJECTIVE: The implementation of policiesthat prohibittobacco smoking in public places has resulted in a significant reduction in secondhand smoke (SHS) exposure in the US population; however, such policies do not extend to private homes, where children continue to be exposed. Our objective was to assess SHS exposure among US children and adolescents by using serum cotinine measures to compare those who were exposed to SHS in the home and those without home exposure. METHODS: We analyzed serum cotinine data from the 2003-2006 National Health and Nutrition Examination Survey for 5518 children (3-11 years) and nonsmoking adolescents (12-19 years). We calculated geometric mean serum cotinine levels by sociodemographic and household characteristics according to self-reported home SHS exposure. Multiple regression analysis was conducted to evaluate independent predictors of serum cotinine levels. RESULTS: Geometric mean serum cotinine levels were 1.05 ng/mL among those with home SHS exposure and 0.05 ng/mL amongthose without home exposure. Among children who were exposed to SHS at home, serum cotinine levels were inversely associated with age and were similar for non-Hispanic black and non-Hispanic white children. Conversely, among children without SHS exposure at home, serum cotinine levels were higher among non-Hispanic black compared with non-Hispanic white children, and there was no relationship with age. Mexican American children had the lowest level of SHS exposure. CONCLUSIONS: Serum cotinine levels were an order of magnitude higher among children with reported SHS exposure at home compared with those with no exposure in the home.