Exposure to several common agricultural pesticides during pregnancy increases the risk of developmental delays and autism in children by two-thirds, a new study found. While researchers did not say pesticides cause autism, a direct link is plausible.
Researchers at the University of California, Davis’ MIND Institute tracked associations with specific classes of pesticides (including organophosphates, pyrethroids and carbamates) and later diagnoses of autism and developmental delay in children. They used maps from the California Pesticide Use Report (1997-2008) and the addresses of expectant mothers to track women’s exposure to agricultural pesticide spraying during their pregnancies.
Developmental delay, in which children take extra time to reach communication, social or motor skills milestones, affects about four percent of US. kids, the authors wrote. The Centers for Disease Control and Prevention estimates that one in 68 children has an autism spectrum disorder (ASD), also marked by deficits in social interaction and language.
Of the 970 children covered by the study, 486 had an ASD, 168 had developmental delays and 316 had typical development.
“We mapped where our study participants’ lived during pregnancy and around the time of birth. In California, pesticide applicators must report what they’re applying, where they’re applying it, dates when the applications were made and how much was applied,” principal investigator Irva Hertz-Picciotto, a MIND Institute researcher and professor and vice chair of the Department of Public Health Sciences at UC Davis, said in a statement. “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.”