Pre- and Postnatal Air Pollution Exposure and Autism Spectrum Disorder

Abstract

TPS 731: Neurological effects in children, Exhibition Hall, Ground floor, August 26, 2019, 3:00 PM - 4:30 PM Background: Epidemiologic studies have reported associations between prenatal and early postnatal air pollution exposure and autism spectrum disorder (ASD); however, few studies to date have assessed associations between air pollution and ASD across different geographic locations using uniform exposure and outcome assessment methods. Methods: We examined associations between early life exposure to PM2.5 and ozone in association with ASD across multiple U.S. regions. Our study participants included 674 children with clinically confirmed ASD and 855 population controls from the Study to Explore Early Development, a multi-site case-control study of children born from 2003 to 2006 in the United States. We used a satellite-based model to assign air pollutant exposure averages during several critical periods of neurodevelopment: three months before pregnancy, each trimester of pregnancy, the entire pregnancy, and the first year of life. Logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CIs), adjusting for study site, maternal age, maternal education, maternal race/ethnicity, maternal smoking, and month and year of birth. Results: The association between air pollution and ASD appeared to vary by exposure time period. PM2.5 exposure during the first year of life was associated with ASD, with an OR of 1.26 (95% CI: 1.02, 1.57) per 1.6 µg/m3 increase in PM2.5. We additionally observed an association with ozone exposure during the third trimester [OR = 1.22 (95% CI: 1.05, 1.42) per 6.6 ppb increase in ozone]. Conclusions: Our study provides evidence for a positive association between early life air pollution exposure and ASD, and identifies a potential critical window of exposure during the late prenatal and early postnatal periods. This abstract does not necessarily represent the official positions of the Centers for Disease Control and Prevention or the Environmental Protection Agency.