To the Editor.
—Contrary to the results of the study by Dr Needleman and colleagues,1 after a 3-decade follow-up study of more than 69 of 110 (63%) of my former patients whose blood lead levels were between 4.83 and 22.68 μmol/L (100 and 470 μg/dL), I have yet to encounter the predicted outcome. Eighty percent of this cohort of inner-city black subjects graduated from high school, a third entered college, and 6 have already obtained 1 or 2 degrees. Three of the college graduates had symptoms of incipient encephalopathy before they received chelation therapy.2Needleman et al leave several questions unanswered. Has the x-ray fluorescence (XRF) technique been validated on children with known lead poisoning (ie, lead concentrations in blood of 3.86 μmol/L [80 μg/dL] or more)? Their study lacks a proper control population.We have lead in our red blood cells at the time of birth, and