Sir.—In a recent clinical report, Moel et al1 detailed the decline in blood lead (Pb-B) levels of 74 patients treated for lead toxicity. They argue that it is unnecessary and perhaps even unwise to chelate children once Pb-B levels have dropped below 2.41 (50 μg/dL). The effect of this advice, if followed, would be to allow large numbers of children to bear body lead burdens in the toxic range for periods of time that most investigators and experienced clinicians would consider dangerously prolonged.
The authors based their conclusion that repeated courses of chelation are unnecessary on the following assertions: (1) that Pb-B levels in their patients eventually declined to below 1.21 μmol/L (25 μg/dL) (it takes about ten years to reach this level); (2) that no significant difference was found in mean postchelation Pb-B levels between groups classified by number of chelations; (3) that the nephrotoxic effects of
Needleman HL, Rosen J, Landrigan P, Graef J. The Hazards of Benign(?) Neglect of Elevated Blood Lead Levels. Am J Dis Child. 1987;141(9):941-942. doi:10.1001/archpedi.1987.04460090018010