Studies Link Prenatal Pesticide Exposure, Lower IQ in Kids
Pesticide exposure in the womb could stunt babies' intelligence, new research suggests. A mother's prenatal exposure to the chemicals—including the kind farmers spray on crops and bug-killers used in homes—could affect the cognitive development of her child up to nine years later, according to three separate studies published today in Environmental Health Perspectives. In one study, researchers at Columbia University found that children whose mothers had the highest levels of the pest-control insecticide chlorpyrifos in umbilical cord blood during delivery scored three points lower on IQ tests at age 7, compared to those whose moms had the lowest levels. Another study, by University of California-Berkeley researchers, found that every 10-fold increase in pesticides detected during a mother's pregnancy corresponded to a 5.5-point drop in her children's IQ scores by age 7. And in the third study, babies whose mothers had high levels of pesticide metabolites in their urine scored lower on cognitive tests beginning at 12 months, and their reasoning abilities remained subpar throughout childhood. "The differences could affect reading comprehension and learning in young children, and affect academic success in school," study author Virginia Rauh, deputy director of the Columbia University Center for Children's Environmental Health, told Time. "We don't think anyone will suggest this type of exposure can result in extreme retardation. But we're talking on average about slightly lower scores of intellectual development that aren't trivial, and could mean a lot to a child."
Pesticide Exposure in the Womb Increases ADHD Risk
Exposure to pesticides while in the womb may increase the odds that a child will have attention deficit hyperactivity disorder, according to researchers at the University of California-Berkeley School of Public Health. Combine that with research published last year in Pediatrics finding that children exposed to pesticides were more likely to have ADHD, and it's enough to make parents wonder how to reduce their family's exposure to pesticides.
The California researchers studied the impact of environmental exposures on the health of women and children who live in the Salinas Valley, an agricultural region with heavy pesticide use. They tested the urine of pregnant women for pesticide residue, and then tested the behavior of their children at ages 3½ and 5. The 5-year-olds who had been exposed to organophosphate pesticides while in the womb had more problems with attention and behavior than did children who were not exposed. What's more, the heavier the pesticide exposure, the more likely that the child would have symptoms of ADHD. The results were published online in Environmental Health Perspectives.
This isn't proof that pesticides cause ADHD, but since organophosphate pesticides are neurotoxins that kill pests by disrupting neurotransmitters that carry signals though the brain, it's easy to imagine that exposure to organophosphate might interfere with brain function and development. Food is a significant source of exposure to pesticide residue. Parents who want to reduce their family's pesticide exposure can consider these moves:
1. Choose cleaner fruits and vegetable. Washing helps remove some pesticide residue, as does peeling. But the surest way to avoid pesticide residue on foods is to buy organic varieties of foods that, when not grown organically, are most likely to have pesticide residue, including celery, peaches, strawberries, apples, and blueberries. Other vegetables like corn and peas are usually low in pesticide residue, even when grown conventionally. The Environmental Working Group, an advocacy organization, has compiled a list of best and worst fruits and vegetables for pesticide residue, which includes a clip-out guide for shopping. [Read more: Pesticide Exposure in the Womb Increases ADHD Risk.]