Pregnant women who are exposed to chemical pesticides, especially those used to treat large farm fields, may be more likely to have babies who are later diagnosed with an autism spectrum disorder (ASD) or other developmental delay. A new study conducted at the University of California Davis reported these findings--the third major study to link pesticide exposure with autism rates--but stopped short of saying that pesticide exposure is definitely a cause of ASD.
The Centers for Disease Control and Prevention's latest numbers suggest that 1 in 68 American children has an autism spectrum disorder, with its causes remaining one of the most vexing mysteries in modern medicine. The debate over whether vaccines cause autism is ongoing despite copious research disproving any link, and a recent British study found that genetics may play as much of a role as whether a child is autistic as environmental exposure does.
For the new study, the researchers used those maps to track exposures during pregnancy for the mothers of 970 children.
The children included 486 with an autism spectrum disorder (ASD), 168 with a developmental delay and 316 with typical development.
In the new study, about a third of mothers had lived within a mile of fields treated with pesticides, most commonly organophosphates.
Children of mothers exposed to organophosphates were 60 percent more likely to have an ASD than children of non-exposed mothers, the authors report in Environmental Health Perspectives.
Image: Tractor spraying a field, via Shutterstock