Physical Sciences and Mathematics Commons^™

Stability Of Blood Lead Levels In Children With Chronic Low-Level Lead Absorption, Michelle Del Rio

Open Access Theses & Dissertations

Background and Significance: Despite the many historical efforts by the U.S. to reduce lead (Pb) in the environment, childhood Pb poisoning continues to be a public health issue today. Pb has been identified as a child hazard because children are highly vulnerable to the effects even at lower levels of exposure (blood lead levels (BLLs) < 10 μg/dL), and these effects can be physical, cognitive, and behavioral. Current state and federal blood lead level screening guidelines for identifying exposed children are based on assumptions that BLLs < 10 μg/dL will remain stable or decline over time (with age); disregard the effects of lowest-range Pb exposure; and disregard Pb levels in children older than approximately age 6. We have observed in past clinical studies that in one U.S./Mexico border community, children in high-risk neighborhoods experienced substantially higher proportions of elevated blood lead levels (CDC reference level of ≥ 5 μg/dL) than the rest of the U.S., and a large proportion of children had detectable blood lead levels. To test current policy assumptions regarding child blood lead level screening, this study examined whether time and/or other possible factors over time, predicted child blood lead levels in children with chronic low-level Pb absorption. Whether time was a significant predictor was examined, and also whether age, sex, and living in families with incomes below the U.S. poverty line, living in an older home, and living near industries predicted child blood lead levels.

Aims and Objectives: Changes in current policy must be evidence-based. The over-arching goal of this study was to test current assumptions that one blood lead level test is sufficient to rule out child lead exposure, and that lead exposure and risk of lead exposure, reliably …