The Centers for Disease Control and Prevention (CDC) lowered the blood lead level (BPb) considered a toxic risk to children from 25 mcg/dL to 10 mcg/dL in Oct 1991. A five-item questionnaire is now completed at regular office visits for all children from 6 months to 6 years of age to identify those at high risk of lead exposure. In some States, including Illinois, all children are required to have BPb testing at 12 months of age or before entering a state-licensed day care, preschool, or kindergarten. High risk infants must be tested at 6 months and biannually.
A study to determine the efficacy of the questionnaire and prevalence of elevated BPb in 1393 suburban children at 12 and 24 months of age is reported from the Department of Pediatrics, Children’s Memorial Hospital, Northwestern University, Chicago, Illinois. A venous BPb =/> 10 mcg/dL was found in 2.1%, and none was >30 mcg/dL. CDC and Illinois screening tests failed to predict high risk exposure in 9 of 29 (31%) children with elevated BPb. Living in a pre-1960 house, a question not included in CDC or Illinois screening, was most predictive, with positive correlation in 24 of 29 (83%) children with elevated BPb levels. The authors point out that optimal risk assessment questions may vary in different areas and populations. 
COMMENT. Questions about the home environment were the most sensitive indicators of elevated lead levels in a similar study reported from the California Pacific Medical Center, San Francisco, CA . An abbreviated screening using only the first three items was as effective as the complete CDC questionnaire in a study at the University of Rochester, NY . Selective screening with a community-specific questionnaire is proposed following a study at the Gunderson Clinic, La Crosse, WI, which found a great variability in prevalence of elevated BPb between clinics even within a homogeneous community. 
A survey of 556 pediatricians in Virginia revealed an overall deficiency in physicians’ knowledge of lead poisoning with specific deficiencies in knowledge of the literature. Subspecialists scored lower than primary care pediatricians . Since 17% of all children < 7 years in the USA are reported to have elevated BPb levels known to increase the risk of cognitive and behavioral deficits, both physician and parent awareness of the environmental sources, symptoms, and long-term hazards of lead is an urgent priority.