The microbial degradation of halogenated diaryl ethers

The structurally related polyhalogenated diaryl ethers such as diphenyl ethers (DEs), dibenzofurans (DFs), and dibenzo-p-dioxins (DDs) are regarded, due to their physicochemical and toxicological properties, as a class of compounds giving reason for serious environmental concern. While the nonhalogenated basic structures are biodegradable under aerobic conditions, there is the need for rather specialized strains to mineralize the halogenated derivatives. Certain halogenated metabolites might cause serious problems such as having inhibitory effects upon the degradation. Anaerobic methanogenic consortia do have the ability to almost completely dehalogenate even polyhalogenated congeners. It has been shown that certain fungi are capable of transforming chlorinated DFs and DDs by the activity of nonspecific enzymes such as lignin-peroxidases.