Prenatal exposure to polychlorinated biphenyls and attention at school age☆
Received 15 November 2002; received in revised form 7 August 2003; accepted 29 August 2003.
Abstract
Objective
To examine the relation of prenatal polychlorinated biphenyl (PCB) exposure to child performance on neuropsychological tests of attention and information processing.
Study design
In this prospective, longitudinal study, assessment of prenatal PCB exposure was based on umbilical cord serum and maternal serum and milk concentrations. The children were tested in their homes at age 11 years. Multiple regression was used to examine the relation of this exposure to performance on 15 neuropsychological tests after controlling for a broad range of potential confounding variables.
Results
Adverse effects were seen primarily in children who had not been breast fed. Among these children, prenatal PCB exposure was associated with greater impulsivity, poorer concentration, and poorer verbal, pictorial, and auditory working memory. There was no evidence of visual-spatial deficit or increased hyperactivity.
Conclusions
These findings are consistent with earlier reports of greater vulnerability to prenatal PCB exposure in children who were not breast fed. It is not clear whether the protection offered by breast-feeding is caused by nutrients in breast milk or better quality of intellectual stimulation often provided by breast-feeding mothers.
From Department of Psychology, Wayne State University, and the Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, Michigan, USA
Reprint requests: Joseph L. Jacobson, PhD, Department of Psychology, Wayne State University, 71 W Warren, Detroit, MI 48202.
☆ Supported by grants R01-ES03256 and R01-ES05843 from the National Institute of Environmental Health Sciences/NIH and grant 80852010 from the US Environmental Protection Agency.
ABSTRACT