ALBERT

Description:    Thiodiglycol (TDG) is both the precursor for chemical synthesis of mustard gas and the product of mustard gas hydrolysis. TDG can also react with intermediates of mustard gas degradation to form more toxic and/or persistent aggregates, or reverse the pathway of mustard gas degradation. The persistence of TDG have been observed in soils and in the groundwater at sites contaminated by mustard gas 60 years ago. The biotransformation of TDG has been demonstrated in three soils not previously exposed to the chemical. TDG biotransformation occurred via the oxidative pathway with an optimum rate at pH 8.25. In contrast with bacteria isolated from historically contaminated soil, which could degrade TDG individually, a consortium of three bacterial strains isolated from the soil never contaminated by mustard gas was able to grow on TDG in minimal medium and in hydrolysate derived from an historical mustard gas bomb. Exposure to TDG had little impacts on the soil microbial physiology or on community structure. Therefore, the persistency of TDG in soils historically contaminated by mustard gas might be attributed to the toxicity of mustard gas to microorganisms and the impact to soil chemistry during the hydrolysis. TDG biodegradation may form part of a remediation strategy for mustard gas contaminated sites, and may be enhanced by pH adjustment and aeration. Content Type Journal Article Category Original Paper Pages 1-11 DOI 10.1007/s10532-012-9564-7 Authors Hong Li, Natural Environmental Research Council, Centre for Ecology and Hydrology, Mansfield Road, Oxford, OX1 3SR UK Robert Muir, Defence Science and Technology Laboratory, Porton Down, Salisbury, Wilts SP4 0JQ, UK Neil R. McFarlane, Defence Science and Technology Laboratory, Porton Down, Salisbury, Wilts SP4 0JQ, UK Richard J. Soilleux, Defence Science and Technology Laboratory, Porton Down, Salisbury, Wilts SP4 0JQ, UK Xiaohong Yu, Natural Environmental Research Council, Centre for Ecology and Hydrology, Mansfield Road, Oxford, OX1 3SR UK Ian P. Thompson, Department of Engineering Science, University of Oxford, Parks Road, Oxford, OX1 3PJ UK Simon A. Jackman, Department of Earth Sciences, University of Oxford, Parks Road, Oxford, OX1 3PR UK Journal Biodegradation Online ISSN 1572-9729 Print ISSN 0923-9820