Sources of Tobacco Smoke Exposure and Their Associations with Serum Cotinine Levels among U.S. Children and Adolescents.

Racial/ethnic disparities in tobacco smoke exposure (TSE) trends have remained stable among U.S. children and adolescents over time. This study's results indicate that TSE locations differentially contribute to biochemically-measured TSE within racial/ethnic groups. Home TSE significantly contributed to cotinine levels among school-aged children 6-11 years old, and car TSE significantly contributed to cotinine levels among adolescents 12-17 years old. Racial/ethnic differences in locations of TSE were observed among each age group. Study findings provide unique insight into TSE sources, and indicate that home and car smoke-free legislation have great potential to reduce TSE among youth of all racial/ethnic backgrounds.