Bioavailability of Lead in Small Arms Range Soils
Abstract
Ammunition manufacture is the second largest consumer of lead (Pb) in the United States after Pb acid batteries and represents approximately 80,000 metric tons per year. About 3000 small arms ranges (SAR) exist, the berms of which act as reservoirs for spent ammunition, and the Department of Defense (DoD) has a vested interest in monitoring the status of these sites so that military personnel may continue to be trained in a sustainable environment. Risk management of Pb at SARs depends on the site end use, whether the range is open or closed, and whether the risk drivers are human or ecologic. The U.S. Environmental Protection Agency s (USEPA) risk assessment guidelines (RAG) allow for applications of site-specific bioavailability for Pb, where this bioavailability differs from the assumed default of 60%. Assessing the site-specific bioavailability of Pb has historically been carried out using the in vivo juvenile swine model, but significant reduction in cost and time could be achieved by using less expensive, less technical, and less time consuming in vitro models. This study compared bioavailability of Pb from SAR soils from eight different sites, using both an established in vivo and in vitro method. The in vivo method was based on the measured absorption of soil-Pb (compared to Pb acetate) by swine dosed daily for 14 days, using the ratio of the blood dose-response slopes for each compound. For the in vitro method, Pb was extracted from an aliquot of soil for 1 hour at 37 C using glycine-HCl buffer at pH 1.5. The extractable Pb was expressed as a percentage of the total Pb in the sample. The initial aims of the study were to compare a projected range of bioavailability in a range of soils, creating a linear comparison between both methods. However, all eight soils carefully selected for testing were determined to have high bioavailability, regardless of source, pH, cation exchange capacity (CEC), or organic matter.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 2009
- Accession Number
- ADA607250
Entities
People
- Desmond I Bannon
- Mick Major
Organizations
- United States Army Center for Health Promotion and Preventive Medicine