The Relation of Subclinical Lead Level to Cognitive and Sensorimotor Impairment in Black Preschoolers

Abstract
The relation of blood lead levels to cognitive and perceptual-performance functioning was determined for 80 black preschool children. Their lead levels were below the criteria set for lead poisoning, but a regression formula revealed that the relationship was significant and as lead level increased general cognitive, verbal, and perceptual abilities decreased. Lead levels were not related significantly to parental intelligence, birth order, birth weight, and number of siblings. Lead level was, however, related to the educational level of the parents. It was concluded that the criteria set for lead poisoning warrant re-examination.