Deficits in Psychologic and Classroom Performance of Children with Elevated Dentine Lead Levels

TLDR

The study compared neuropsychologic performance between 58 children with high dentine lead levels and 100 with low levels to assess lead exposure effects. Neuropsychologic performance was assessed with the Wechsler Intelligence Scale and classroom behavior was evaluated through teacher questionnaires for all children whose dentine lead levels were measured. Children with higher dentine lead levels had significantly lower IQ scores, poorer verbal, auditory, and attention performance, and exhibited dose‑related increases in non‑adaptive classroom behavior, indicating neuropsychologic deficits that impair classroom performance. N Engl J Med 300:689–695, 1979.

Abstract

To measure the neuropsychologic effects of unidentified childhood exposure to lead, the performance of 58 children with high and 100 with low dentine lead levels was compared. Children with high lead levels scored significantly less well on the Wechsler Intelligence Scale for Children (Revised) than those with low lead levels. This difference was also apparent on verbal subtests, on three other measures of auditory or speech processing and on a measure of attention. Analysis of variance showed that none of these differences could be explained by any of the 39 other variables studied. Also evaluated by a teachers' questionnaire was the classroom behavior of all children (2146 in number) whose teeth were analyzed. The frequency of non-adaptive classroom behavior increased in a dose-related fashion to dentine lead level. Lead exposure, at doses below those producing symptoms severe enough to be diagnosed clinically, appears to be associated with neuropsychologic deficits that may interfere with classroom performance. (N Engl J Med 300:689–695, 1979)