Long-term Exposure to PM(10) and NO(2) in Association with Lung Volume and Airway Resistance in the MAAS Birth Cohort

Background: Findings from previous studies on the effects of air pollution exposure on lung function during childhood have been inconsistent. A common limitation has been the quality of exposure data used, and few studies have modeled exposure longitudinally throughout early life. Objectives: We sought to study the long-term effects of exposure to particulate matter with an aerodynamic diameter ≤ 10 μm (PM(10)) and to nitrogen dioxide (NO(2)) on specific airway resistance (sR(aw)) and forced expiratory volume in 1 sec (FEV(1)) before and after bronchodilator treatment. Subjects were from the Manchester Asthma and Allergy Study (MAAS) birth cohort (n = 1,185). Methods: Spirometry was performed during clinic visits at ages 3, 5, 8, and 11 years. Individual-level PM(10) and NO(2) exposures were estimated from birth to 11 years of age through a microenvironmental exposure model. Longitudinal and cross-sectional associations were estimated using generalized estimating equations and multivariable linear regression models. Results: Lifetime exposure to PM(10) and NO(2) was associated with significantly less growth in FEV(1) (percent predicted) over time, both before (–1.37%; 95% CI: –2.52, –0.23 for a 1-unit increase in PM(10) and –0.83%; 95% CI: –1.39, –0.28 for a 1-unit increase in NO(2)) and after bronchodilator treatment (–3.59%; 95% CI: –5.36, –1.83 and –1.20%; 95% CI: –1.97, –0.43, respectively). We found no association between lifetime exposure and sR(aw) over time. Cross-sectional analyses of detailed exposure estimates for the summer and winter before 11 years of age and lung function at 11 years indicated no significant associations. Conclusions: Long-term PM(10) and NO(2) exposures were associated with small but statistically significant reductions in lung volume growth in children of elementary-school age. Citation: Mölter A, Agius RM, de Vocht F, Lindley S, Gerrard W, Lowe L, Belgrave D, Custovic A, Simpson A. 2013. Long-term exposure to PM(10) and NO(2) in association with lung volume and airway resistance in the MAAS birth cohort. Environ Health Perspect 121:1232–1238. http://dx.doi.org/10.1289/ehp.1205961