PT02 Soil Toxicology and Risk Assessment
Exhibit Hall
8:00 AM - Tuesday, 11 November 2003
(PT018) Toxicity of a new polynitramine energetic material CL-20 to Enchytraeus crypticus in amended natural soil.
Kuperman, R.1, Checkai, R.1, Simini, M.1, Phillips, C.1, Anthony, J.1, Kurnas, C.1, Kolakowski, J.1, 1 U.S. Army Edgewood Chemical Biological Center, Aberdeen Proving Ground, MD, USA
ABSTRACT- We are investigating the toxicity of a new polynitramine energetic material hexanitrohexaazaisowurtzitane (CL-20) to the soil invertebrate species Enchytraeus crypticus. Studies were designed to develop ecotoxicological benchmark values for ecological risk assessment of the potential impacts of the release of this compound into the environment. Tests are being conducted using a Sassafras sandy loam soil that supports relatively high bioavailability of CL-20. Toxicity testing was performed in freshly amended soil using the Enchytraeid Reproduction Test (ISO/16387:2001) to measure adult survival and juvenile production by the potworm E. crypticus, and is ongoing for weathered/aged amended soil. Measurement endpoints are assessed using 7-13 treatment concentrations with four replicates per treatment. Appropriate negative, carrier (acetone), and positive controls are included. Adult survival and juvenile production data are analyzed using nonlinear regression models with ECp parameter, to determine the CL-20 concentration producing a specified percentage effect, including EC50 and EC20 levels. Preliminary results show that CL-20 toxicity to E. crypticus, in freshly amended soil is greater than the other nitramine energetic compounds RDX and HMX. The ongoing testing of weathered/aged CL-20 amended soil will provide information on the potential alterations in CL-20 ecotoxicity in contaminated field sites.
Key words: toxicity, CL-20, Enchytraeus crypticus, soil