"Women who are exposed to high levels of air pollution during their third trimester of pregnancy may be twice as likely to have an autistic child, a study found.

Researchers from the Harvard School of Public Health found the risk of autism rises in parallel with exposure to fine particulate matter during pregnancy, with the biggest effect occurring in the final months of gestation. The results appear in the Dec. 18 edition of Environmental Health Perspectives.

The findings add to other research suggesting the environment plays a role in the development of autism, a developmental disorder marked by repetitive behaviors and trouble communicating and socializing. The study, which started in 1989 and involved more than 100,000 nurses from across the U.S., will help researchers home in on the causes of autism and potential ways to prevent it, said Marc Weisskopf, a senior study author."

Michelle Fay Cortez reports for Bloomberg Businessweek December 18, 2014. [2]