Relationship between lead exposure indicators and neuropsychological performance in children

This study surveyed 237 schoolchildren in a lead-polluted industriaI area in northern Italy to assess the relationship between various biological indicators (lead in blood, hair and teeth, and deltaaminolevulinic dehydratase [ALA-D] activity) and some neuropsychological functions, assessed by a battery of five psychometric tests. The geometric means of lead measured in blood, hair and teeth were 1O.99 ug/dl, 6.79 ug/g and 6.05 ug/g, respectively. Mean ALA-D activity was 5l mU/mi RBC. By analysis of covariance, after regressing out the variance accountable to confounding variables (age, sex, occupation/education of parents), Total and Verbal WISC-R IQ and Toulouse Pieron test results were significantly affected by the levels of lead in teeth. ALA-D values also appeared to be related to WISC-R IQ results (Total, Verbal and Performance)