Objective: Determining whether early developmental effects of perinatal exposure to polychlorinated biphenyls (PCBs) or dichlorodiphenyl dichloroethene (DDE) persist.
Design: Cohort followed from birth; ages now 5 1/2 to 10 1/2 years.
Setting: General community.
Participants: Volunteer sample of 859 children, of whom 712 had been examined with the McCarthy Scales of Children's Abilities at 3, 4, or 5 years; 506 sent report cards.
Measurements and results: Neither transplacental nor breast-feeding exposure to PCBs or DDE affected McCarthy scores at 3, 4, or 5 years. There was no statistically significant relationship between poorer grades and PCB or DDE exposure by either route.
Conclusions: The deficits seen in these children on the Bayley Scales of Infant Development through 2 years of age are no longer apparent.