ABSTRACT
OBJECTIVE: To determine whether exposure to polychlorinated biphenyls (PCBs) or dichlorodiphenyl dichloroethene (DDE), either transplacentally or through breast feeding, affected scores on the Bayley Scales of Infant Development at 6 or 12 months of age. DESIGN: Cohort followed from birth to 1 year of age. SETTING: General community. PARTICIPANTS: Volunteer sample of 858 infants, of whom 802 had Bayley scores available at either 6 months or 12 months or both. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Bayley scales and chemical measurements were done independently. Higher transplacental exposure to PCBs was associated with lower psychomotor scores at both 6 and 12 months of age; the difference between the mean scores in the lowest and highest PCB groups was 7 points at 6 months and 8 points at 12 months. Higher transplacental exposure to DDE was associated with higher mental scores at 6 months of age (the difference between the mean scores in the lowest and highest DDE groups was 6 points), but no relationship was seen at 12 months. Exposure to either chemical through breast feeding was apparently unrelated to Bayley scores. CONCLUSIONS: Transplacental exposure to PCBs was associated with lower psychomotor scores. No deleterious effects were associated with breast feeding.
Subject(s)
Breast Feeding , Child Development/drug effects , Dichlorodiphenyl Dichloroethylene/adverse effects , Milk, Human/analysis , Polychlorinated Biphenyls/adverse effects , Prenatal Exposure Delayed Effects , Brain/drug effects , Child, Preschool , Dichlorodiphenyl Dichloroethylene/analysis , Female , Follow-Up Studies , Humans , Infant , Infant, Newborn , Intelligence/drug effects , Neuropsychological Tests , Polychlorinated Biphenyls/analysis , Pregnancy , Psychomotor Performance/drug effectsABSTRACT
Neonatal effects of transplacental exposure to polychlorinated biphenyls (PCBs) and dichlorodiphenyl dichloroethene (DDE) were examined in a study of 912 infants. Birth weight, head circumference, and neonatal jaundice showed no relationship to PCBs or DDE. We also administered the Brazelton Neonatal Behavioral Assessment Scales, which are psychologic and neurologic tests designed for use in newborn infants. The results of these tests showed that higher PCB levels were associated with hypotonicity and hyporeflexia and that higher DDE levels were associated with hyporeflexia.