Prenatal exposure to PM₁₀ and NO₂ and children's neurodevelopment from birth to 24 months of age: mothers and Children's Environmental Health (MOCEH) study.

INTRODUCTION

Previous studies have suggested adverse effects of maternal exposure to air pollution on neurodevelopment in early childhood.

OBJECTIVES

We aimed to investigate the association between prenatal exposure to particulates of less than 10 μm in diameter (PM10) and nitrogen dioxide (NO2) and neurodevelopment in children during the first 24 months of their lives.

METHODS

The MOCEH study is a prospective birth cohort study in South Korea. Average exposure levels to PM10 and NO2 during the entire pregnancy were estimated using the inverse distance weighting (IDW) method. A total of 520 mother-child pairs who completed neurodevelopmental assessments using the Korean Bayley Scale of Infant Development II (K-BSID-II) more than once at ages of 6, 12 and 24 months were included. Mental developmental index (MDI) and psychomotor developmental index (PDI) from the K-BSID-II were used as outcome variables.

RESULTS

There were negative associations between maternal exposure to PM10 and MDI (β=-2.83; p=0.003) and PDI (β=-3.00; p=0.002) throughout the first 24 months of life as determined by the generalized estimating equation (GEE) model. Maternal NO2 exposure was related with impairment of psychomotor development (β=-1.30; p=0.05) but not with cognitive function (β=-0.84; p=0.20). In a multiple linear regression model, there were significant effects of prenatal air pollution exposure on MDI (PM10: β=-4.60; p<0.001, NO2: β=-3.12; p<0.001) and PDI (PM10: β=-7.24; p<0.001, NO2: β=-3.01; p<0.001) at 6 months, but no significant association was found at 12 and 24 months of age.

CONCLUSIONS

The findings suggest that exposure to air pollution may result in delayed neurodevelopment in early childhood.