Prenatal PM exposure and neurodevelopment at 2 years of age in a birth cohort from Mexico city.

BACKGROUND

Recent studies have reported that air pollution exposure may have neurotoxic properties.

OBJECTIVE

To examine longitudinal associations between prenatal particles less than 2.5 μm in diameter (PM) exposure and neurodevelopment during the first two years of children's life.

METHODS

Analysis was conducted in PROGRESS, a longitudinal birth cohort between 2007 and 2013 in Mexico City. We used satellite data to predict daily PM concentrations at high spatial resolution. Multivariate mixed-effect regression models were adjusted to examine cognitive, language and motor scores in children up to 24 months of age (n = 740) and each trimester-specific and whole pregnancy exposure to PM.

RESULTS

Models adjusted by child sex, gestational age, birth weight, smoking and mother's IQ, showed that each increase of 1 μg/m of PM was associated with a decreased language function of -0.38 points (95% CI: -0.77, -0.01). PM exposure at third trimester of pregnancy contributed most to the observed association.

CONCLUSION

Our findings suggest that language development up to 24 months of age may be particularly sensitive to PM exposure during pregnancy.