Maternal blood lead effects on infant intelligence at age 7 months.

A sample of 7-month-old African-American infants, exposed to maternal blood lead levels less than 5 microg/dL, were assessed with the Fagan test of Infant Intelligence. The results indicate significant effects on memory and cognitive functioning. Specifically, infants who scored in the upper 5th to 15th percentile of novelty preference scores had lower lead values than those scoring in the lower 5th or 15th percentile. Of note, is the finding that no infant who scored in the upper percentile range was ever classified as having high maternal blood lead levels. These results are in accord with previous studies that report relationships between low-level lead exposure and nonoptimal infant development.