Medical inpatients in inner-city hospitals have both potentially lead-related disorders and potential lead exposure. To see whether there is substantial unexpected lead intoxication in this population, we did a cross-sectional study of 117 consecutively admitted patients to a general medical ward of an inner-city university hospital. The mean (SD) blood lead level was 6.7 (2.8) micrograms/dL, with a range of 0 to 37 micrograms/dL. Twenty-one patients (18%) had mildly elevated lead levels (10 to 19 micrograms/dL) and 2 patients (2%) had moderately elevated lead levels (20 to 44 micrograms/dL). Only 1 of 117 patients (0.9%, 95% CI: 0.0% to 2.6%) had lead intoxication (a lead level > or = 20 micrograms/dL or a lead level > or = 15 micrograms/dL and a free erythrocyte protoporphyrin level > 90 micrograms/dL of erythrocytes, with no alternative explanation for the laboratory abnormalities). We conclude that lead intoxication is uncommon in this population and that routine screening is not warranted. Although mild elevation of blood lead level is common, the clinical significance remains to be determined.