Brenda Eskenazi, Ph.D.
University of California, Berkeley
Teens who had higher prenatal exposure to organophosphate pesticides had altered brain activity while performing certain tasks, according to a new NIEHS-funded study. Although prenatal exposure to these pesticides has been linked to poor cognition and behavior problems in children, this study is the first to demonstrate specific changes in the brain that may help explain why.
The team used an imaging technique called functional near-infrared spectroscopy (fNIRS) to visualize blood flow and activity in different brain regions. They monitored the brains of 95 teens aged 15 to 17 years who performed tasks related to executive function, attention, social cognition, and language comprehension. Prenatal exposure to pesticides was estimated for each of the teens based on their mother’s residential proximity to pesticide use during pregnancy. Compared with those with lower estimated exposure, teens with higher estimated prenatal pesticide exposure were found to have less blood flow to the frontal cortex while performing tasks related to cognitive flexibility and visual memory but had higher blood flow to the parietal and temporal lobes during tests recalling words.
According to the authors, decreased activation during the more complex tasks may point to altered overall neural response, whereas increased activation may indicate higher cognitive demand to complete simpler tasks. They suggest that fNIRS is an inexpensive and practical alternative to neuroimaging for understanding the impact of environmental exposures on brain function.
Citation: Sagiv SK, Bruno JL, Baker JM, Palzes V, Kogut K, Rauch S, Gunier R, Mora AM, Reiss AL, Eskenazi B. 2019. Prenatal exposure to organophosphate pesticides and functional neuroimaging in adolescents living in proximity to pesticide application. Proc Natl Acad Sci U S A 116(37):18347−18356.