Association between lead poisoning among children less than six years old and lead service pipes in Washington DC

Objective: We conducted a study to examine the association between childhood blood lead levels (BLLs) and exposure to lead service pipes in Washington DC. Methods: A cross-sectional analysis of 49,048 children who lived in Washington DC and received at least one blood lead test between 1998 and 2006 was conducted. Regression models were developed to examine the association between exposure to lead service pipes (LSP) and the increase in BLLs. Covariates considered included gender, age at time of test, sample type, age of the housing unit, whether the housing unit had a lead service pipe, and the year of the test. Results: After adjusting for potential confounders, the association between exposure to LSP and having a BLL ≥5 µg/dL did not remain statistically significant. Likewise, children with BLLs ≥10 µg/dL were more likely to have lived in a pre-1978 or pre-1950 housing unit (p<0.0001), were younger age (p<0.0001) and more likely to have lived in a housing unit with a LSP (p<0.0001) compared to children with ≤10 µg/dL. The association between exposure to lead service pipe and having a BLL ≥10 µg/dL remained statistically significant after controlling for potential confounders. Conclusions: The strongest predictor of a child having a BLLs ≥5 µg/dL included the child being a younger age and having lived in a pre-1950 or 1978 housing unit. However among children with BLLs ≥10 µg/dL the strongest predictors included a child living in a home with a LSP or living in a pre-1950 or 1978 housing unit.