Prenatal, Early-Life, and Childhood Exposure to Air Pollution and Lung Function: The ALSPAC Cohort

Rationale: Exposure to air pollution during intrauterine development and through childhood may have lasting effects on respiratory health. Objectives: To investigate lung function at ages 8 and 15 years in relation to air pollution exposures during pregnancy, infancy, and childhood in a UK population-based birth cohort. Methods: Individual exposures to source-specific particulate matter <10 mm in aerodynamic diameter (PM10) during each trimester, 0-6 months, 7-12 months (1990-1993), and up to age 15 years (1991-2008) were examined in relation to FEV1% predicted and FVC% predicted at ages 8 (n = 5,276) and 15 (n = 3,446) years using linear regression models adjusted for potential confounders. A profile regression model was used to identify sensitive time periods. Measurements and Main Results: We did not find clear evidence of a sensitive exposure period for PM10 from road traffic. At age 8 years, 1 mg/m(3) higher exposure during the first trimester was associated with lower FEV1% predicted ( 20.826; 95% confidence interval [CI], 21.357 to 20.296) and FVC% predicted (20.817; 95% CI, 21.357 to 20.276), but similar associations were seen for exposures for other trimesters, 0-6 months, 7-12 months, and 0-7 years. Associations were stronger among boys, as well as children whose mother had a lower education level or smoked during pregnancy. For PM10 from all sources, the third trimester was associated with lower FVC% predicted (21.312; 95% CI, 22.100 to 20.525). At age 15 years, no adverse associations with lung function were seen. Conclusions: Exposure to road-traffic PM10 during pregnancy may result in small but significant reductions in lung function at age 8 years.