Study finds link between pesticides and autism

Jun 23, 2014

WASHINGTON (AFP) - A California study out on Monday found that pregnant women who lived near farms where pesticides are applied had a two-thirds higher risk of having children with autism.

The findings in the journal Environmental Health Perspectives examine the association between living near commercial pesticide applications and having offspring with autism, but do not show cause-and-effect.

Autism is a neurodevelopmental disorder that ranges in severity and has been on the rise in recent years. Health authorities say it now affects as many as one in 68 children in the United States.

The latest research was based on data about commercial pesticide applications in California, combined with residential addresses of about 1,000 participants in a study of families with an autistic child.

"We mapped where our study participants' lived during pregnancy and around the time of birth," said principal investigator Irva Hertz-Picciotto, vice-chairman of the Department of Public Health Sciences at the University of California, Davis.

California law requires detailed records on what kinds of pesticides are applied, where and when and how much.

"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." About one-third of study participants lived within 1.25km to 1.75km of a site where commercial pesticides were applied.

Researchers found risks of autism were highest when the chemicals were applied during the second and third trimesters of pregnancy.

The study authors said the developing foetal brain may be particularly vulnerable to pesticides.

"This study validates the results of earlier research that has reported associations between having a child with autism and prenatal exposure to agricultural chemicals in California," said lead study author Janie Shelton, a UC Davis graduate student.

"While we still must investigate whether certain sub-groups are more vulnerable to exposures to these compounds than others, the message is very clear: Women who are pregnant should take special care to avoid contact with agricultural chemicals whenever possible."

[I am interested in Autism and the possible cause of it, and so I have included this news report as part of the "research" or findings on autism and the cause of it.

However, the Straits Times report is atrociously incomplete and possibly alarmist.

The actual report is more nuanced. There is this paragraph:

Earlier this year, scientists examining more than two million births in Sweden reported that inherited genes make up about 50 percent of a child’s autism risk, while environmental factors make up the other half.

And this:

Earlier this year, researchers showed that people with a gene variant associated with autism and high exposure to air pollution had an increased risk of autism over people with the same gene variant but lower exposure to air pollution.

Which suggest that genetics also play a part.

Also the age of the father.

But if you need to do something, here's a finding that may help:

... one recent study suggests that taking folic acid during pregnancy may actually decrease chances for ASD. ]