Superfund Research Program
In utero Exposure to Polychlorinated Biphenyls, Pesticides and Metals in Relation to Cognitive Function in Childhood
Project Leader: Susan A. Korrick
Grant Number: P42ES005947
Funding Period: 1995 - 2006
Final Progress Reports
Year: 2005 1999
This study was undertaken to assess the impact of low-level intrauterine toxin exposure (PCBs, DDT, DDE and lead) on fetal and infant development at exposure levels characteristic of the general U.S. population. Over 790 newborns were enrolled and examined for this study from March 1993 through December 1998. Over the course of the past year, six-month follow-up developmental assessments were completed on a total of 275 of these infants. In addition, researchers completed a pilot assessment of memory and learning ability (with the Wide Range Assessment of Memory and Learning, WRAML) on approximately 70 of the children who were between the ages of five and six years.
Preliminary data analyses have been completed for many of the outcomes and exposures of interest and several manuscripts are in preparation. Results of these ongoing analyses support the following findings: (1) Prenatal PCB and DDT/DDE exposures (assessed primarily with cord serum concentrations) in this population were generally lower than those described previously in other birth cohorts for which neurodevelopmental effects of these compounds have been studied; (2) Increasing cord serum PCB levels were associated with lower birth weight independent of gestational age; (3) Increasing cord serum PCB levels were associated with delayed neuromuscular maturation (in the Dubowitz exam) and increased hyporeflexia (in the Brazelton Neonatal Behavioral Assessment Scale), consistent with findings described previously among other populations; (4) Increasing milk PCB levels were associated with poorer visual memory (in the Fagan Test of Infant Intelligence) at age six months among the most exposed infants (upper third of milk PCB concentrations); and (5) Results of preliminary analyses of our small pilot study of five to six-year-olds suggest that increasing milk PCB levels are associated with poorer visual memory, story memory, and learning although none of these associations was statistically significant in this small sample.