The online issue of Environmental Health Perspectives posted on Dec. 18 the findings of a study that emphasizes the link between pregnant women exposed to air pollution and the onset of autism in their newborn children.
Study shows that the risk for their offsprings to develop autism was twice as high if the women were exposed to fine particulate matter (PM) in the third trimester of pregnancy. The research team included senior author Marc Weisskopf, associate professor of environmental and occupational epidemiology at Harvard School of Public Health in Boston, MA.
They analyzed 116,430 women residents of 50 states, who took part in the Nurses’ Health Study II, which started in 1989. Their children were also examined. Furthermore, they noted each woman’s location during her pregnancy and established the fine PM levels that the women might have been exposed to, before the pregnancy, but also during each semester and after she had given birth. They obtained the information regarding fine particle pollution from the US Environmental Protection Agency and various other sources.
The scientists found that 245 children were diagnosed with autism. For comparison, 1,522 children acted as controls. The exposure to air pollution before and after pregnancy was not found to be associated with risk of children developing autism. The same conclusion was reached regarding particles of a larger size.
The results were discussed by: “Our data adds additional important support to the hypothesis that maternal exposure to air pollution contributes to the risk of autism spectrum disorders. The specificity of our findings for the pregnancy period, and third trimester in particular, rules out many other possible explanations for these findings.”
Autism spectrum disorders or ASDs are defined as developmental disorders that affect a child’s ability to share feelings and thoughts, with various social repercussions. In the past 2 years, autism prevalence has risen to 30 %. In 2012, 1 in 88 children was diagnosed with this condition. In 2014 it has increased to 1 in 68.
Other similar studies have also taken notice of this particular link. One of them was done in June of this year. The scientists concluded that pregnant women who live near pesticide sites, in comparison to those who don’t, have an increased risk of giving birth to children suffering from autism or other developmental deficits.
In conclusion, these finding mark an important step in understanding the causes and factors that influence such disorders. However, one must remember that although Weisskopf’s study found this particular association, it couldn’t prove that exposure to air pollution actually caused autism.
Image Source: University of Wisconsin-Madison