环境中一溴联苯醚(4-BDE)的来源和降解

Sources and Remediation of 4-Monobrominated Diphenyl Ether( 4-BDE)

一溴联苯醚(4-BDE)为多溴联苯醚脱溴后的最终产物,是重要的环境持久性有机污染物。分析4-BDE成因及其环境降解机制是进行4-BDE植物修复机制研究以及建立其类似物植物修复方法的理论基础。环境介质中4-BDE主要由高溴代联苯醚经光解和生物代谢降解产生。4-BDE经过复杂的代谢机制被光氧化形成联苯醚、羟基联苯醚、苯酚、苯、羧酸以及具有腐殖酸类化合物等多种光解产物。4-BDE经厌氧微生物作用后,降解产物主要有联苯醚和溴离子。好氧微生物可利用4-BDE作为生长碳源,在酶的作用下开环并彻底降解为CO2和H2O。

4-BDE,one of the dominant reductive debromination products,has become important environmental contaminants. The analysis of sources and environmental remediation of 4-monobrominated diphenyl ether（ 4-BDE）provided theoretical basis for phytoremediation mechanism or analogue phytoremediation method. 4-BDE was mainly formed by photodegradation and biodegradation higher-brominated PBDEs. The photo-oxidation of 4-bromodiphenylether has been shown to generate a large number of photoproducts such as diphenylether,parahydroxy diphenylether,phenol,benzene,carboxylic acids and aliphatic halogen compounds. After debrominated by anaerobic microbes,the by-products,diphenyl ether（ DE） and bromide ions,were monitored. Aerobic microbes can use 4-BDE as carbon source and degraded by enzymes with ring breakage. The products are CO2 and H2O.