The amount of pesticide a woman is exposed to while pregnant could affect her child’s IQ years later.
As Time magazine reports, three studies published in the journal Environmental Health Perspectives have linked lower IQs among children whose mothers had higher-than-average exposures during pregnancy to household bug spray or crop spray in farming communities.
In one study that began in 1997, Columbia University researchers found that children born to mothers who had the highest levels of a pesticide called chlorpyrifos in their blood
scored 3 points lower on IQ tests at age 7 than children whose mothers had the lowest exposure to the pesticide. Chlorpyrifos was an ingredient in household bug spray until it was banned for indoor use by the U.S. Environmental Protection Agency in 2000.
Another study, which focused on California farmworker families, measured the relationship between children’s IQ scores and levels of a byproduct of organophosphate pesticides. Researchers from the University of California at Berkeley
Mt. Sinai Medical Center researchers, in the third study, equated higher levels of organophosphate pesticides in the urine of pregnant women with a decreased reasoning ability among their children, who were tested as late as 9 years old.
“These studies are unusual in that they are the first to look at prenatal exposure at a low level—at levels that would occur in everyday life, and not levels that would poison us –and followed the children prospectively,” said Brenda Eskenazi, director of the Center for Environmental Research and Children’s Health at UC Berkeley.
Significantly, although the pesticide exposure levels of study participants were elevated, they still fell within a range of exposure considered acceptable in the United States, prompting one of the study authors to suggest that the EPA needs to tighten its definition of what are acceptable pesticide exposures.
In the meantime, researchers said that expectant mothers could reduce their exposure to pesticides by thoroughly washing fruits and vegetables. Instead of using bug spray indoors, they should use alternatives like baits and traps.