Prenatal Exposure to Pesticide Chlorpyrifos Linked to Brain Abnormalities

FRIDAY, Aug. 22, 2025 (HealthDay News) — Prenatal exposure to the pesticide chlorpyrifos (CPF) is associated with altered differentiation of neuronal tissue, increased myelination of the internal capsule, and lower regional blood flow throughout the brain, according to a study published online Aug. 18 in JAMA Neurology.

Bradley S. Peterson, M.D., from the Children”s Hospital Los Angeles, and colleagues conducted a prospective, longitudinal pregnancy cohort study from January 1998 to July 2015 to identify associations of prenatal CPF exposure with brain structure, function, and metabolism in school-aged children. A total of 512 pregnant women of African American or Dominican descent had CPF levels measured at delivery. Offspring aged 6 years and older were approached for magnetic resonance imaging scanning (270 participants).

The researchers found a significant association for progressively higher prenatal CPF exposure levels with progressively thicker frontal, temporal, and posteroinferior cortices; reduced white matter volumes in these regions; higher fractional anisotropy and lower diffusivity in internal capsule white matter; reduced regional blood flow throughout the brain; lower indices of neuronal density in deep white matter tracts; and poorer performance on both fine motor and motor programming tasks in children.

“Blood flow is an important indicator of underlying metabolism — the energy used by brain tissue. In my opinion, it”s maybe the most important finding of the paper, because it says that globally there”s a problem with brain metabolism in direct proportion to how much CPF exposure they had,” Peterson said in a statement.

One author disclosed ties to Evolve Adolescent Behavioral Health, personal fees for expert testimony, and several patents.

Abstract/Full Text