Is Prenatal Exposure to Organophosphate Pesticides Associated with Attention-Deficit/Hyperactivity Disorder?

Organophosphate pesticides inhibit acetylcholinesterase activity and thereby increase levels of acetylcholine in the central nervous system. Recent studies suggest that fetal exposure to organophosphates is associated with abnormal neonatal reflexes and poorer performance on infant mental development scales. To explore this association further, investigators measured dialkyl phosphate (DAP) metabolites of organophosphate pesticides in maternal urine at two time points during pregnancy in 348 Mexican American women (mean age, 26) who delivered healthy newborns in a California agricultural community. Attention was measured by maternal report (Child Behavior Checklist), direct assessment, and psychometricians' reports of the children's behavio…