A 4-YEAR FOLLOW-UP-STUDY OF CHILDREN BORN TO CONSUMERS OF LAKE-MICHIGAN FISH

Children exposed pre- and postnatally to polychlorinated biphenyls (PCBs) and related contaminants due, in part, to their mothers' consumption of Lake Michigan fish were evaluated at age 4 years. Higher umbilical cord serum PCB levels were associated with lower weight and poorer cognitive function in two domains-short-term memory and cognitive processing speed. The memory deficit was observed in tests of auditory verbal and quantitative memory and visual pictorial memory; the processing speed deficit, in a visual discrimination task. Although much larger quantities of PCBs were transferred postnatally via breast-feeding than across the placenta, postnatal exposure was not related to any physical growth or cognitive deficits. The only outcome associated with postnatal exposure was a small reduction in activity level. Although the magnitude of these associations was modest, even relatively subtle deficits in short-term memory and speed of information processing may have a significant impact on the child's ability to master basic reading and arithmetic skills in school.