Summary Review of the Aquatic Toxicology of Munitions Constituents.

摘要

Military munitions are present in waters around the world, including those waters located at current and former Department of Defense sites. This report provides a review of the aquatic ecotoxicology of munitions constituents (MC), including nitroaromatics (2,4,6- trinitrotoluene (TNT), dinitrotoluenes (DNTs), 1,3,5-trinitrobenzene (TNB), 2,4,6-trinitrophen ylmethylnitramine (tetryl) and 2,4,6- trinitrophenol (picric acid)); nitrate esters (nitrocellulose (NC), pentaerythritoltetranitrate (PETN), nitroglycerine (NG)); and nitramines (hexahydro-1,3,5- trinitro-1,3,5-triazine (RDX), and octahydro-1, 3,5,7-tetranitro- 1,3,5,7-tetrazocine (HMX)). The major focus of this report is on the fate and effects of MC in the marine environment. Most MC observed in this study rapidly degraded in aqueous exposure systems and nitroaromatics showed a significant binding affinity with organic matter. To support the assessment of risk from MC in aquatic environments, laboratory-based toxicity data have been derived for a variety of aquatic species for both lethal and sublethal exposure endpoints using spiked water or sediment. Frequently, unrealistically high concentrations were used to derive toxicity benchmarks. In general, nitramines were less toxic than nitroaromatics, with a wide range of sensitivity among species. MC are weakly hydrophobic and bioaccumulative potential was low, as expected. High elimination rates for MC resulted in a virtually complete loss of body residue within hours to days following transfer to clean water. Uptake of TNT resulted in the substantial formation of bound residues. For fish, aqueous exposure was the dominant route of exposure to explosive compounds, with dietary uptake providing only minimal contribution. More realistic exposures using Composition B and multiple species found the presence of munitions in aquatic environments unlikely to result in biological effects. Verification of this conclusion should be pursued by determining site-specific exposure risk.