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USGS · 70024836

Microbial mineralization of ethene under sulfate-reducing conditions

P. M. Bradley·F. H. Chapelle
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Abstract

Previous investigations demonstrated that respiratoly reductive dechlorination of vinyl chloride (VC) can be efficient even at H 2 concentrations (≤2 n M ) that are characteristic of SO 4 -reducing conditions. In the study reported here, microorganisms indigenous to a lake-bed sediment completely mineralized [1,2- 14 C] ethene to 14 14CO 2 when incubated under SO 4 -reducing conditions. Together, these observations argue for a novel mechanism for the net anaerobic oxidation of VC to CO 2 : reductive dechlorination of VC to ethene followed by anaerobic oxidation of ethene to CO 2 . Moreover, the results of this study suggest that reliance on ethene and/or ethane accumulation as a quantitative indicator of complete reductive dechlorination of chioroethene contaminants may not be warranted.

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P. M. Bradley, F. H. Chapelle. 2002. Microbial mineralization of ethene under sulfate-reducing conditions. https://doi.org/10.1080/10889860290777431

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