INTRODUCTION

In October 1991, the Centers for Disease Control and Prevention (CDC) issued lead screening guidelines¹ that

1. Recommended blood lead screening for virtually all 1-year-old children and, when resources permit, for all 2-year-old children as well;
2. Suggested five questions that physicians could use to assess whether an individual child might be at risk for lead poisoning;
3. Offered recommendations regarding further testing and follow-up should a blood lead level (BLL) 10 µg/dL be found.

In 1993, the American Academy of Pediatrics (AAP) published recommendations² similar to those of the CDC. Both sets of recommendations were influenced by reports demonstrating adverse neuropsychologic effects from BLLs as low as 10 µg/dL^3,4 and by data from the second National Health and Nutrition Examination Survey (NHANES II), conducted 1976-1980, showing that 88% of 1- to 5-year-old children had BLLs 10 µg/dL.^5,6

	MORE RECENT DEVELOPMENTS

Subsequent to publication of the 1991 CDC and 1993 AAP guidelines, data from a number of blood lead screening studies demonstrated marked variation in the prevalence of elevated BLLs.^7-12 Publication of data from these studies, many appearing in the February 1994 issue of this journal, resulted in a commentary in the same issue that questioned the appropriateness of the CDC screening and follow-up recommendations.¹³

Variation in the prevalence of children with BLLs 10 µg/dL ranged from 71% in central Philadelphia⁹ and 28% in central Rochester⁸ to 3.6% in Chicago suburbs⁷ and 0.6% in Alaska Medicaid children.¹⁰ In the Chicago area study, 0.1% of children had a BLL 20 µg/dL, and in Alaska none had a BLL 11 µg/dL.

Results of Phase I (1988-1991) of NHANES III, which were unavailable when the 1991 CDC guidelines were developed, showed a marked reduction in the geometric mean (GM) BLL of 1- to 5-year-old children compared with NHANES II.¹⁴ The GM BLL was now 3.6 µg/dL compared with 15 µg/dL just 12 years earlier. More recent data from Phase . . . [Full Text of this Article]