Assessing the Risks to Young Children of Three Effects Associated with Elevated Blood-Lead Levels

摘要

Formal risk assessments were conducted as part of the US Environmental Protection Agency's current review of the primary National Ambient Air Quality Standard for lead. The assessments focused on three potentially adverse effects of exposure to lead in children from birth through the seventh birthday: erythrocyte protoporphyrin (EP) elevation, hemoglobin (Hb) decrement, and intelligence quotient (IQ) effect. The same general strategy was followed in all three cases: for two levels of each effect, probability distributions over population response rate were estimated at a series of blood-lead (PbB) levels. These distributions were estimated from data in the case of EP elevation and from expert judgements in the cases of Hb decrement and IQ effect. Although of interest in their own right, these estimates were combined with PbB distributions to yield probability distributions over the estimated percentages of children experiencing the particular health effects. 15 refs., 24 figs., 24 tabs. (ERA citation 12:012518)