Dr. Mary Schooling, professor at the CUNY Graduate School of Public Health and Health Policy and an international team of investigators examined the association of air pollution with birth weight and gestational age. The findings were published in the Journal of Public Health (Oxf).
[Photo: Dr. Mary Schooling]
Studies from Western settings have found inconsistent associations of air pollutants with birth outcomes. Because of residual confounding by socioeconomic status, the research team assessed this association in the economically developed non-Western setting of Hong Kong, which has high levels of air pollution but little social patterning of these birth outcomes.
The team obtained air pollution data (PM10, SO2, NO and NO2) from monitoring stations, and assessed their associations with birth weight and gestational age in a large population-representative birth cohort ‘Children of 1997’. The team statistically accounted for the collinearity between pollutants.
There was an association of PM10 and NO2 with a birth weight decrease of 47.0 g and 16.9 g, respectively; and with 2.1 days and 0.7 days shorter gestational age, respectively.
Given minimal confounding by socioeconomic status in Hong Kong, these findings provide unequivocal evidence of adverse effects of PM10 and NO2 exposure during pregnancy on birth weight and gestational age. Physiological mechanisms need to be better understood to support effective public health action globally.