Irva Hertz-Picciotto, Ph.D., Rob McConnell, M.D., Heather Volk, Ph.D.
University of California-Davis, University of Southern California
NIEHS Grants R21ES019002, P30ES007048, P01ES011269, R01ES015359
NIEHS grantees report that exposure to local traffic-related air pollution and regional air pollution in the womb and during the first year of life is associated with increased risk for autism. The study builds on previous research in which the grantees found that children born to mothers who live within 309 meters of freeways had an increased risk of developing autism.
In the new study, the researchers examined data from children enrolled in the Childhood Autism Risks from Genetics and the Environment study, including 279 children with autism and 245 control children with normal development. They estimated traffic-related pollution exposures using the mother’s address and used U.S. Environmental Protection Agency’s Air Quality System measurements of regional pollution.
The children with autism were more likely than the control children to live in homes with the highest exposure to traffic-related air pollution during gestation and the first year of life (Gestation: AOR, 1.98 [95 percent CI, 1.20-3.31]; First year: AOR, 3.10 [95 percent CI, 1.76-5.57]). During gestation, exposure to regional nitrogen dioxide and particulate matter less than 2.5 and 10 microns in diameter (PM2.5 and PM10) was also associated with autism. The researchers say that additional population and toxicological studies of likely biological pathways are needed to determine if the air pollution exposure causes the increase in autism risk.
Citation: Volk HE, Lurmann F, Penfold B, Hertz-Picciotto I, McConnell R. 2012. Traffic-Related Air Pollution, Particulate Matter, and Autism. Arch Gen Psychiatry; doi:10.1001/jamapsychiatry.2013.266. [Online November 2012]