Exposure to air pollution and lung development during childhood: the LUIS Study

Abstract

Background: Adverse effects of high air pollution levels on lung function during childhood are well known. Limited evidence exists on adverse effects of lower exposure levels on lung growth during school age.

Objective: To investigate the association of low-to moderate air pollution using different time windows with lung development in a population-based study.

Methods: Fine scale spatio-temporal model estimates of particulate matter with a diameter <2.5 µm (PM_2.5) and nitrogen dioxide (NO₂) were linked with residential address histories in 2187 schoolchildren. Exposures within different time windows (pregnancy, first year of life, preschool age) with forced expiratory volume in 1 s (FEV₁) and forced vital capacity (FVC) measured at 12 years (range 7-17) were compared. We used linear regression models adjusted for potential confounders.

Results: Prenatal air pollution exposure was associated with reduced lung function at school age. Per 10 µg/m³ increase in PM_^2.5 during pregnancy, the adjusted results were 50 ml lower for FEV₁ (95% CI -50 to -19 ml) and 56 ml lower for FVC (95% CI -92 to -20 ml). PM2.5 exposure during the other time windows was not associated with subsequent lung function. NO₂ during any of the time window was not associated with subsequent lung function.

Conclusion: Even modest PM_2.5 exposure during the prenatal time may result in reduced lung function during school age.