Pregnant women exposed to high levels of air pollution are twice as likely to give birth to a child with autism compared to women who experience low levels of air pollution.
The first nationwide study examining associations between air pollution and autism spectrum disorder (ASD) was conducted by scientists from Harvard School of Public Health (HSPH) and published in Environmental Health Perspectives.
Pollutants can affect a developing fetus
“Our findings raise concerns since, depending on the pollutant, 20 percent to 60 percent of the women in our study lived in areas where risk of autism was elevated,” said lead author Andrea Roberts, a research associate in the HSPH Department of Social and Behavioral Sciences.
Previous studies have shown that methylene chloride, lead, mercury, manganese, diesel and other particulates found in polluted air can affect a fetus and baby.
Extensive data gathered and honed
Roberts and her colleagues gathered data from the Nurses’ Health Study II and focused on 325 women who gave birth to an ASD babies, comparing them to 22,000 women whose children did not have the disorder.
The Nurses’ Health Study, which began in 1989, is continually collecting data on 116,430 nurses nationwide. The research team also looked at data from the EPA to estimate how much air pollution the mothers were exposed to while pregnant. They factored in lifestyle choices and other variables in order to focus on the effect of air pollution.
Boys seem more vulnerable
The determination was that pregnant mothers living in areas with the most air pollution (focusing on diesel and mercury) had twice the risk of having a child with autism than women who lived in areas with the lowest levels.
When considering other pollutants like lead, methylene chloride, manganese and combined metal exposure, there was a 50 percent higher risk of autism for the pregnant women living in those areas. There is a closer association of autism and pollution if the mother is carrying a boy.
More information will point to better preventive strategies
“Our results suggest that new studies should begin the process of measuring metals and other pollutants in the blood of pregnant women or newborn children to provide stronger evidence that specific pollutants increase risk of autism,” explained senior author Marc Weisskopf. “A better understanding of this can help to develop interventions to reduce pregnant women’s exposure to these pollutants.”
Source: MedicalNewsToday
