Requisites of Soil Testing to Measure Toxic Metal Bioavailability to Adjust Risk from the Human Soil Ingestion Exposure Pathway.

Human exposure of risk assessment has matured and soil testing methods to evaluate bioavailability-based risk assessment frameworks are being developed and implemented.  For example, U.S. EPA has published Technology Performance Measures to evaluate the remedial success of soil amendments used for remediation, revitalization, and reuse of metal-contaminated soil. The success is evaluated by measuring the reduction of risks to human health and the environment. The TPM framework specifies direct and indirect methods estimate site-specific metal bioavailability. Using indirect in vitro methods as a proxy for an organism provides a simple and inexpensive means to estimate metal bioavailability and exposure from contaminated soils. In this presentation, we focus on the requisites of soil testing methods to measure metal bioavailability associated with the incidental ingestion of soil exposure pathway.  The ability of currently used methods to meet requisites will be presented.