A RISK-EVALUATION OF THE NEUROPSYCHOLOGICAL EFFECTS OF CHILDHOOD LEAD TOXICITY

As part of a risk evaluation of the neurobehavioral toxicity of lead in children, research findings were summarized from various human epidemiological studies according to the type of design used. Irrespective of whether the research evidence being considered is from medical case series studies, case-control, cross-sectional retrospective cohort, or prospective longitudinal cohort research, the findings consistently support a relationship between lead exposure and cognitive impairment in children, even at lower blood levels (10 to 15 mu g/dl). Furthermore, experimental research in primates suggests that these exposure levels disrupt more complex perceptual discrimination ability in subtle and permanent ways, perhaps by fundamentally disrupting attentional processes when lead alters synaptogenesis in the developing brain. If considering the research evidence in its entirety, the epidemiologic criteria are met for causality in terms of the effects of lead exposure on neurobehavioral development and attentional ability in children. We conclude that even at the 10 mu g/dl blood level of lead-a level considered safe by most standards' of public health policy ill America today-a cause-and-effect relationship for neuropsychological impairment can be reasonably demonstrated. This should have significant bearing on public health policy considerations in ensuring the neuropsychological well-being of millions of American children.