Microbial debromination of hexabromocyclododecanes
Fei Yu1, Yuyang Li1, Hui Wang1
1Department of Biology, Science College, Shantou University, Shantou, 515063, Guangdong Province, People's Republic of China.
Applied Microbiology and Biotechnology
|June 2, 2021
Summary
Microbial debromination transforms Hexabromocyclododecanes (HBCDs), persistent pollutants. Combining bioaugmentation with phytoremediation offers a promising strategy for HBCD bioremediation in contaminated sites.
Area of Science:
- Environmental Science
- Microbiology
- Toxicology
Background:
- Hexabromocyclododecanes (HBCDs) are prevalent, persistent, and toxic environmental pollutants.
- HBCDs are detected globally in environmental matrices and human tissues, raising health concerns.
- Despite their recalcitrance, HBCDs are biodegradable, with numerous bacteria capable of transforming them.
Purpose of the Study:
- To review current knowledge on microbial debromination of HBCDs.
- To promote the application of bioremediation for HBCD-contaminated sites.
- To highlight promising strategies for effective HBCD pollution management.
Main Methods:
- Review of existing literature on microbial degradation pathways of HBCDs.
- Analysis of microbial debromination mechanisms including hydrolytic debromination, HBr-elimination, and HBr-dihaloelimination.
- Evaluation of biotic transformation products and their ecological toxicity.
Main Results:
- Microbial transformation of HBCDs results in hydroxylated and lower brominated compounds.
- Degradation pathways for HBCDs are often co-opted from those established for other organohalides.
- Bioremediation of HBCD pollution has been limited to laboratory-scale applications.
Conclusions:
- Microbial debromination is a key process in the environmental fate of HBCDs.
- A combined approach of bioaugmentation and phytoremediation shows significant promise for HBCD bioremediation.
- Further research and application are needed to scale up laboratory findings to real-world contaminated sites.
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