BACKGROUND: In a longitudinal birth cohort study of inner-city mothers and children (Columbia Center for Children’s Environmental Health), we have previously reported that prenatal exposure to chlorpyrifos (CPF) was associated with neurodevelopmental problems at child age 3 years.
OBJECTIVE: The goal of the study was to estimate the relationship between prenatal CPF exposure and neurodevelopment among cohort children at age 7 years.
METHODS: In a sample of 265 children, participants in a prospective study of air pollution, we measured prenatal CPF exposure using umbilical cord blood plasma (picograms/gram plasma), and 7-year neurodevelopment using the Wechsler Intelligence Scales for Children (WISC-IV). Linear regression models were used to estimate associations, with covariate selection based on two alternate approaches.
CONCLUSIONS: We report evidence of deficits in Working Memory Index and Full-Scale IQ as a function of prenatal CPF exposure at 7 years of age. These findings are important in light of continued widespread use of CPF in agricultural settings and possible longer-term educational implications of early cognitive deficits.