Quantifying the Bioavailability of Toxic Metals in Soil
Abstract
The primary objective of this research was to investigate the relative bioavailability of the toxic metals lead (Pb), cadmium (Cd), arsenic (As), and chromium (Cr) in soils, particularly in relation to the human health risk posed by soil ingestion, which often controls the degree of clean-up required at metal-contaminated sites. These metals were selected because they are the metals of greatest concern at Department of Defense (DoD) facilities (Exponent, 2001). The research was motivated by the following hypotheses: Hypothesis 1 The ubiquitous metal-sequestering properties of soil will significantly lower the relative bioavailability of ingested metals when compared to the 100% default relative bioavailability values currently used in risk assessments. Hypothesis 2 Key soil physical and chemical properties [particle size, CEC, pH, Fe, Mn, and natural organic matter (NOM) concentration] will be good predictors of soil-metal bioavailability. Hypothesis 3 Metal bioavailability is controlled by molecular-level speciation, where metal sequestration and solid phase stability are enhanced by increased soil-metal residence time.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 2003
- Accession Number
- ADA604130
Entities
People
- Mark O. Barnett
- Philip M. Jardine
- Scott E. Fendorf
Organizations
- Auburn University