| Abstract | The ecotoxicological effects of four bioslurry reactors treating 2,4,6-trinitotoluene (TNT)- and 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX)-spiked soil were evaluated. A control bioslurry reactor was used to assess the en-dogenous toxicity of the bioslurry operation conditions. A battery of ecotoxicity tests was used: Microtox, green al-gae growth inhibition, bacterial genotoxicity and mutagenicity, and earthworm mortality and growth inhibition.Bioslurry soluble and solid phases were separated by centrifugation in order to identify toxicity and possible toxi-cants associated with each phase. Microtox toxicity values were initially very high in both bioslurry reactors spikedwith TNT, in relation with TNT concentration. Initial toxicity was also detected by algal growth inhibition, earth-worm lethality, genotoxicity and mutagenicity tests. An endogenous toxicity was detected in the control bioreactorusing the Microtox and the SOS Chromotest. The soluble phase of the control bioslurry was genotoxic, suggestingthat some potentially genotoxic agents were induced in the bioslurry samples. At the end of the bioremediation treat-ment, data showed that toxicity was reduced using all of the bioassays, except for earthworm lethality and growthinhibition tests in both RDX-spiked bioslurries. This study demonstrates the usefulness of a battery of toxicity teststo monitor bioremediation processes. |
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