2019
Author(s): Wang Q, Liang Q, Li C, Ren M, Lin S, Knibbs LD, Zhang H, Gong W, Bao J, Wang S, Wang X, Zhao Q and Huang C
BACKGROUND: This study aimed to assess if air pollutants and meteorological factors synergistically affect birth outcomes in Shenzhen, China. METHODS: A total of 1,206,158 singleton live births between 2005 and 2012 were identified from a birth registry database. Daily average measurements of particulate matter =10 microm (PM10), sulfur dioxide (SO2), nitrogen dioxide (NO2), ambient air temperature (T), and dew point temperature (Td), a marker of humidity, were collected. Multivariable logistic regression models were used to evaluate associations between air pollution and small for gestational age (SGA), and full-term low birth weight (TLBW). We classified births into those conceived in the warm (May-October) and cold seasons (November-April) and then estimated interactions between air pollutants and meteorological factors. RESULTS: An interquartile range (IQR) increase in PM10 exposure during the first trimester (23.1 microg/m) and NO2 during both the first and second trimesters (15.1 and 13.4 microg/m) was associated with SGA and TLBW risk; odds ratios ranged from 1.01 (95% confidence interval [CI] = 1.00, 1.02) to 1.09 (1.07, 1.12). We observed interactive effects of both air temperature and humidity on PM10 and SGA for newborns conceived in the warm season. Each IQR increase in PM10 (11.1 microg/m) increased SGA risk by 90% (95% CI = 19%, 205%), 29% (23, 34%), 61% (10, 38%), and 26% (21, 32%) when T < 5th percentile, 5th < T < 95th percentile, Td < 5th percentile, and 5th < Td < 95th percentile, respectively. CONCLUSIONS: Our study found evidence of an interactive effect of air temperature and humidity on the relationship between PM10 exposure and SGA among newborns conceived in the warm season (May-October). Relatively low air temperature or humidity exacerbated the effects of PM10.
Journal: Epidemiology