ENVIRONMENTAL EXPOSURES TO LEAD AND URBAN CHILDRENS BLOOD LEAD LEVELS

Lead-contaminated water, soil, and paint have been recognized as poten tial sources of children's lead exposure for decades, but their contri butions to lead intake among urban children remain poorly defined. Thi s analysis was undertaken to estimate the relationship of environmenta l lead exposures to lead intake among a random sample of urban childre n, adjusted for exposure to lead-contaminated house dust. Analyses of 183 urban children enrolled in a random sample, cross sectional study were conducted. Children's blood and multiple measures of household du st, water, soil, and paint were analyzed for lead, and interviews were conducted to ascertain risk factors for childhood lead exposure. Envi ronmental sources of lead, including house-dust, soil lead, and water lead, were independently associated with children's blood lead levels. In contrast, paint lead levels did not have a significant effect on b lood lead levels after adjusting for other environmental exposures. An increase in water lead concentration from background levels to 0.015 mg/L, the current EPA water lead standard, was associated with an incr ease of 13.7% in the percentage of children estimated to have a blood lead concentration exceeding 10 mu g/dL; increasing soil lead concentr ation from background to 400 mu g/g was estimated to produce an increa se of 11.6% in the percentage of children estimated to have a blood le ad level exceeding 10 mu g/dL, and increasing dust lead loading from b ackground to 200 mu g/ft(2) is estimated to produce an increase of 23. 3% in the percentage of children estimated to have a blood lead level exceeding 10 mu g/dL. These data support the promulgation of health-ba sed standards for lead-contaminated dust and soil and the progressive lowering of standards for lead-contaminated water as the definition of undue lead exposure has been modified. (C) 1998 Academic Press.