To the Editor.
—We write to address several issues raised by the recent report on lead poisoning among low-income children in Orange County by Gellert et al.1Several well-designed prospective cohort studies2,3 and a meta-analysis4 suggest that lead produces adverse neurological effects at blood lead levels at least as low as 0.50 μmol/L (10 μg/dL), the current level of concern as defined by the CDC. Although Gellert et al state that "pediatric lead poisoning is not a major problem affecting Orange County children," they report a 7.25% prevalence of blood lead levels of 0.50 μmol/L (10 μg/dL) or higher among children in that county. Many Orange County children, therefore, have evidence of increased lead exposure.The statement by Gellert et al that "no action other than retesting is indicated" for children with blood lead levels of 0.50 μmol/L (10 μg/dL) is inaccurate. The CDC recommends that several