Expectant Mothers Exposed to Pesticides Linked to Autism

Expectant mothers who live within a mile of where pesticides are used have an increased risk of autism developing in their child.

According to the study published June 23 in the journal Environmental Health Perspectives, researchers studies 1,000 families with children who were 2 to 5-years-old. 316 of these children were developing healthy, 486 were diagnosed with autism, and 168 had another developmental delay. The mother’s were asked to list their address and where they were living before and during pregnancy.

Researchers compared this data to a database of pesticide usage in California that provided information about what chemicals were used, when they were used, and how much was used.

While only a third of the women had been living no greater than a mile away from where the chemicals were used, the study found that the risk of autism developing in these babies were 60-200% higher than those who did not live close by pesticide use.

The risk is greater during the last three months of pregnancy.

Autism, a neurodevelopmental disorder that causes social and behavioral impairments, affect one in 68 children in the United States.

Pesticides are used to kill and control pests, used most commonly in agriculture to ward off microorganisms, insects and other animals, and plants like weeds. Pesticides include insecticides, herbicides, fungicides, and other substances.

“Many of these compounds work on neurons. When they work on the insect, they’re dealing with the nervous system of the insect and basically incapacitating it,” said study author Irva Hertz-Picciotto, an environmental epidemiologist at the MIND Institute at University of California, Davis.

Because the brain is not yet fully developed during pregnancy, these harmful chemicals affect the vulnerable nerve cells in the baby.

The study did not site specific chemicals as the culprit, and did not weigh in how pesticides found in food could contribute. Household products such as bug spray, kitchen and bath disinfectants, pet collars and flea and tick sprays, and products that kill mold all contain pesticides.