Current needs for increased accuracy and precision in measurements of low levels of lead in blood.

Needs for accurate and precise measurements of low levels of lead in blood are discussed. Current methodologies are sufficient for measuring blood lead (PbB) levels greater than 0.5 microM, but the accuracy and precision of those methodologies are inadequate for measuring lower (less than 0.5 microM) PbB concentrations. These analytical limitations are primarily due to contamination bias incurred during sample collection, processing, and analyses. Consequently, trace metal-clean procedures should be adopted to elucidate the contribution of environmental lead to the PbB levels of the U.S. population and to estimate the threshold(s) of subclinical lead toxicity.