Evaluation of performance of a mouse assay to estimate the oral relative bioavailability of lead in soils and dusts

Assessing bioavailability of lead (Pb) in soil and dust is an important strategy to (1) improve accuracy in human health risk assessments and (2) evaluate the effectiveness of remediation strategies to reduce Pb bioavailability in situ. A rapid, relatively low cost, and reproducible mouse bioassay to measure soil Pb relative bioavailability (RBA) serves several important roles in bioavailability research, including (1) calibration, evaluation, and improvement of in vitro bioaccessibility assays for predicting RBA; (2) identification of site-specific factors that contribute to variability in RBA, such as soil geochemistry and Pb speciation; and (3) development of new chemical remediation methods that decrease soil Pb bioavailability in situ and protect public health. The aim of this study was to compare intra- and interlab performance of a mouse assay that measured Pb RBA in soil and dust. The assay exhibited reliable intra- and interlab reproducibility, with no significant differences in RBA of 5 test materials measured in two labs. Repeated intralab analysis of a single test material also demonstrated significant reproducible measurement of Pb RBA. These results support more widespread application of mouse assay to determine soil Pb RBA to inform human health risk assessment and soil remediation decisions.