Toxicity and Bioaccumulation of Munitions Constituents in Aquatic and Terrestrial Organisms

Abstract

Explosives and their transformation products are present in terrestrial and aquatic environments around the globe and have the potential to cause toxicity to the biota inhabiting contaminated environments. This chapter summarizes the available data on the toxicity of explosives and their transformation products to microbes, soil and aquatic invertebrates, terrestrial plants, aquatic autotrophs, and terrestrial plants, as well as data on their potential to bioaccumulate. While RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) and HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) typically remain untransformed, nitroaromatic explosives undergo fast transformation when added to soils and sediment, posing challenges when establishing concentration-response relations. The cyclic nitramines RDX and HMX typically caused no or minor adverse effects on biological receptors whereas 2,4,6-trinitrotoluene (TNT) caused lethal effects to most species investigated, in addition to sublethal effects on growth and reproduction reported for some species. Overall, nitroaromatic explosives are expected to pose greater risk to terrestrial and aquatic biota at contaminated sites compared to nitramine explosives. The toxicity of other explosives compounds was also summarized. As predicted mainly on the basis of their low hydrophobicity, bioaccumulation studies confirmed the low potential of explosives to accumulate in plants, fish, and invertebrates.