Scientific rationale for updating policies on responding to low level lead exposures

New recommendations from the Advisory Committee on Childhood Lead Poisoning Prevention to the Centers for Disease Control (Department of Health and Human Services) include the elimination of the use of a ‘level of concern' for blood lead effects in children, based on the inability to define a ‘safe' blood lead level. This recommendation, which was based on a weight of evidence approach, emerged from an analysis of studies that have been reported, particularly over the past 10 years, related to deficits in cognitive/executive functions, including learning and attention-related behaviors. These associations of low blood lead levels with cognitive deficits represent findings from a large number of diverse groups of children. It has also become clear from such studies that adverse effects are associated with concurrently measured blood leads in children, consistent with ongoing effects of lifetime exposures. Nor do such deficits appear to be confined to lower socioeconomic status populations. New findings also suggest that the adverse health effects of BLLs less than 10 µg/dL in children extend beyond cognitive function to include cardiovascular, immunological, and endocrinological effects. This presentation will summarize this new evidence. As these adverse effects appear to be irreversible in the absence of other interventions, they underscore the critical need for primary prevention.