Effective elution of RDX and TNT from particles of Comp B in surface soil.

During live fire training exercises, large amounts of explosives are consumed. Low order detonations of high explosive payloads result in the patchy dispersal of particles of high explosive formulations over large areas of firing range soils. Dissolution of explosives from explosive formulation particles into soil pore water is a controlling factor for transport, fate, and effects of explosive compounds.

Post-Katrina fecal contamination in Violet Marsh near New Orleans.

Fecal material entrained in New Orleans flood waters was pumped into the local environment. Violet Marsh received water pumped from St. Bernard Parish and the Lower Ninth Ward.

Biodegradation of the cyclic nitramine explosives RDX, HMX, and CL-20.

Cyclic nitramine explosives are synthesized globally mainly as military munitions, and their use has resulted in environmental contamination. Several biodegradation pathways have been proposed, and these are based mainly on end-product characterization because many of the metabolic intermediates are hypothetical and unstable in water. Biodegradation mechanisms for cyclic nitramines include (a) formation of a nitramine free radical and loss of nitro functional groups, (b) reduction of nitro functional groups, (c) direct enzymatic cleavage, (d) alpha-hydroxylation, or (e) hydride ion transfer.

The mechanism of unimolecular decomposition of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane. A computational DFT study.

By using the B3LYP level of density functional theory, possible decomposition reaction pathways of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) in the gas phase have been investigated. We have found several types of reactions for this process: homolytic cleavage of an N-N bond to form the NO2* group; HONO elimination; C-C and C-N bonds breaking leading to ring opening; and H-migration. On the basis of the results of computation scanning of the potential energy surface, the most favorite pathway of CL-20 unimolecular decomposition that results in the formation of the stable aromatic compound 1,5-dihydrodiimidazo[4,5-b:4',5'-e]pyrazine has been proposed.

Mineralization of the cyclic nitramine explosive hexahydro-1,3,5-trinitro-1,3,5-triazine by Gordonia and Williamsia spp.

Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) is a cyclic nitroamine explosive that is a major component in many military high-explosive formulations. In this study, two aerobic bacteria that are capable of using RDX as the sole source of carbon and nitrogen to support their growth were isolated from surface soil. These bacterial strains were identified by their fatty acid profiles and 16S ribosomal gene sequences as Williamsia sp.