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Development of Sulfidogenic Sludge from Marine Sediments and Trichloroethylene Reduction in an Upflow Anaerobic Sludge Blanket Reactor
Published on: October 15, 2015
Chloroethene biodegradation in sediments at 4 degrees C
P M Bradley1, S Richmond, F H Chapelle
1U.S. Geological Survey, 720 Gracern Rd., Suite 129, Columbia, SC 29210, USA. pbradley@usgs.gov
Applied and Environmental Microbiology
|October 6, 2005
Summary
Cold-adapted Alaskan microbes can break down trichloroethene (TCE) and its byproducts, cis-dichloroethene (cis-DCE) and vinyl chloride (VC), into carbon dioxide (CO2) in cold, anoxic environments.
Area of Science:
- Environmental microbiology
- Bioremediation
- Cold-region science
Background:
- Trichloroethene (TCE) is a common environmental pollutant.
- Cold temperatures can inhibit microbial degradation of contaminants.
- Alaskan environments present unique challenges for bioremediation due to low temperatures.
Purpose of the Study:
- To investigate microbial reductive dechlorination and anaerobic oxidation of TCE and its metabolites in cold Alaskan sediments.
- To assess the potential for bioremediation of chlorinated ethenes in cold climates.
Main Methods:
- Preparation of anoxic microcosms using cold-adapted aquifer and river sediments from Alaska.
- Incubation of microcosms at 4 degrees C.
- Tracing the microbial transformation of [1,2-14C]trichloroethene, [14C]cis-dichloroethene, and [14C]vinyl chloride to 14CO2.
Main Results:
- Microbial reductive dechlorination of [1,2-14C]trichloroethene to [14C]cis-dichloroethene and [14C]vinyl chloride was observed at 4 degrees C.
- Microbial anaerobic oxidation of [14C]cis-dichloroethene and [14C]vinyl chloride to 14CO2 was confirmed under the same conditions.
Conclusions:
- Cold-adapted microorganisms in Alaskan sediments can effectively degrade trichloroethene and its daughter products under anaerobic and cold conditions.
- These findings support the potential for in situ bioremediation of chlorinated ethene contamination in cold environments.
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