Prenatal Exposure to Pesticides Found to Impact Teen Brain Activity

A new study led by the University of California, Berkeley is the first to use advanced brain imaging to show how prenatal exposure to organophosphates – one of the most commonly used classes of pesticides in the US – changes brain activity, according to a news release from the university.

The study, published in Proceedings of the National Academy of Sciences, monitored the blood flow in the brains of 95 teenagers born and raised in California’s Salinas Valley, where the use of pesticides is common. These teens, when compared to their peers, “showed altered brain activity while performing tasks that require executive control”.

“These results are compelling because they support what we have seen with our neuropsychological testing, which is that organophosphates impact the brain,” lead study author Sharon Sagiv said.

These findings build on a longitudinal study that began more than 20 years ago with the establishment of the Center for the Health Assessment of Mother and Children of Salinas, or “CHAMACOS”, which means “little children” in Mexican Spanish – the primary population this study observes and serves. This study has spearheaded almost 150 publications, including identifying links between organophosphate exposure with attention problems and lower IQs in children.

This specific study used functional near-infrared imaging (fNIRS) to measure brain activation while teens ages 15-17 engaged in a variety of tasks requiring executive function, attention, social cognition, and language comprehension. They also used California Pesticide Use Reporting data to estimate the participants’ residential proximity to the organophosphate application during pregnancy.

They found a correlation between prenatal exposure to the pesticides and the amount of blood flow to the frontal cortex when participating in cognitive testing.

“With fNIRS and other neuroimaging, we are seeing more directly the potential impact of organophosphate exposure on the brain, and it may be more sensitive to the neurological deficit than cognitive testing,” senior study author Brenda Eskenazi said.