A study by researchers at the UC Davis Mind Institute shows that maternal exposure to agricultural pesticides is associated with increased risk of autism in children.
The findings, published in the journal 'Environmental Health Perspectives', determine the link between living near commercial pesticide applications and having children with autism. The researchers, however, did not show a cause-and-effect relation.
For the study, Irva Hertz-Picciotto and team examined around 1,000 women and their children enrolled in the Northern California-based Childhood Risk of Autism from Genetics and the Environment (CHARGE) Study. The participants were told to provide their residential details before and after conceiving the child.
The team then gathered pesticide application data from the California Pesticide Use Report. They then measured each participant's proximity to the pesticide applied sites and noted down the particular chemical each person was exposed to while expecting their child.
Researchers found that staying within a limit of 1.25 to 1.75 kilometres to a commercial pesticide application site during pregnancy was directly associated to autism in the offspring.
Moreover, the team found that the risks of autism were highest when the chemicals were applied during the second and third trimesters of pregnancy. According to the study authors, the developing fetal brain may be particularly vulnerable to pesticides.
"We mapped where our study participants' lived during pregnancy and around the time of birth," said lead researcher Hertz- Picciotto, vice chair of the Department of Public Health Sciences at University of California, Davis, in a press release.
As per the California law, detailed records on what kinds of pesticides are applied are necessary.
"What we saw were several classes of pesticides more commonly applied near residences of mothers whose children developed autism or had delayed cognitive or other skills," she said.
The study findings are published in the journal Environmental Health Perspectives.
