A number of studies have emerged citing that exposure to air pollution is a contributing factor to autism. Researchers have been scrambling to find a reason for the substantial increase in autism prevalence which has increased by 30% in the last 2 years alone, from 1 in 88 children affected by the disorder in 2012 to 1 in 68 children in 2014.
Another study has emerged citing that women who live in areas with high levels of fine particulate matter during pregnancy may be at high risk of having a child with autism.
The Harvard School of Public Health found that exposure to fine particulate matter (PM) in the third trimester of pregnancy substantially increases autism. Their findings were published in the Environmental Health Perspectives journal.
The research data consisted of 116,430 women and their children from 50 states who were part of the Nurses’ Health Study II, which began in 1989. The researchers recorded where the women lived during their pregnancy, and data from the US Environmental Protection Agency and other sources was evaluated to determine the levels of fine PM the women would have been exposed to before pregnancy, throughout each trimester and after pregnancy.
The team identified 245 children who were diagnosed with autism during the study period, as well as 1,522 children without autism to act as controls.
“Our data add additional important support to the hypothesis that maternal exposure to air pollution contributes to the risk of autism spectrum disorders”, said senior author Marc Weisskopf, associate professor of environmental and occupational epidemiology at Harvard School of Public Health in Boston. “The specificity of our findings for the pregnancy period, and third trimester in particular, rules out many other possible explanations for these findings.” “This not only gives us important insight as we continue to pursue the origins of autism spectrum disorders,” he adds, “but as a modifiable exposure, opens the door to thinking about possible preventative measures.”
Autism spectrum disorder and particulate matter air pollution before, during, and after pregnancy: A nested case-control analysis within the Nurses’ Health Study II cohort, Marc Weisskopf, et al., Environmental Health Perspectives, published online 18 December 2014.