Moderately elevated blood lead levels: effects on neuropsychologic functioning in children.

Investigations of moderately elevated lead levels and children's cognitive functioning have yielded conflicting results, although studies showing no effects used measures of limited sensitivity and breadth. In this study, a comprehensive neuropsychologic battery was used to determine whether deficits would be revealed. An experimental group of 15 children with a past history of moderately elevated lead levels, but subsequently without increased lead levels for at least a year, were compared with a control group matched by residential area, socioeconomic status, parental IQ, age, and gender. The experimental groups' performance was lower on the battery overall and on measures of motor skill, memory, language, advanced spatial functions, and concentration. The results suggest that exposure to moderately elevated lead levels exerts significant and nontransient effects on cognitive functions.