Prevalence of lead poisoning in an urban cohort of infants with high socioeconomic status.

The purpose of this study was to assess the prevalence of lead poisoning in an urban cohort of infants with high socioeconomic status and to determine the usefulness of the Centers for Disease Control (CDC) questionnaire in predicting lead poisoning. The CDC questionnaire was administered to consecutive parents of infants, beginning with their 6-month well-child visit. All infants had a venous lead level by 12 months of age. The 165 infants were between 5.9 and 12 months (mean = 9.4 months). The majority (67%) lived in a major city, had parents who were college graduates (67%), and had private medical insurance (85%). The overall prevalence of lead poisoning (Pb > or = 10 micrograms/dL [0.483 mumol/L]) was 29%. The relative risk of lead poisoning, given exposure as defined by the CDC instrument, was 0.99 (95% CI = .81 to 1.21). The sensitivity and specificity of the questionnaire were 40% and 60%, respectively. We conclude that the prevalence of lead toxicity and the poor sensitivity of the CDC questionnaire in this cohort of urban infants with high socioeconomic status support the 1991 CDC recommendation for universal lead screening in this region.