Previous investigations studying the fate of TNT in fresh, brackish and saline water have shown that the compound and its degradation products rapidly adsorb to the sediment. One issue to consider when it comes to risk assessment of TNT-leaking ammunition in water is whether the compound binds hard enough to the sediment, thus becoming unavailable to sediment-living invertebrate organisms. On behalf of the Swedish Armed Forces, FOI Division of NBC Defence and the University of Göteborg have investigated the extractability of TNT and its degradation products from sediment and the toxicity in small crustaceans. Independent of the water salinity, less than 1% of the added TNT was found in the water phase after 77 days of incubation. The acute toxicity of the sediments in small crustaceans was the same before as after the leaching of the sediments with water at high pressure and temperature (10 MPa, 150 °C). In conclusion, this study has shown that the risk for toxic effects in small animals arising from spreading of biologically and/or chemically degraded TNT from the sediment to the surroundings is low.