Polychlorinated biphenyls microbial activity

Quensen, J.F., III, M.A. Mousa, S.A. Boyd, B.J.T. Sanderson, K.L. Froese, and J.P. Giesy. 1998. Reduction of aryl hydrocarbon receptor-mediated activity of polychlorinated biphenyl mixtures due to anaerobic microbial dechlorination. Environ. Toxicol. Chem. 17 806-813. 

More oxidized compounds, such as chlorinated benzenes, are susceptible to biologically mediated reduction in environments under anaerobic conditions, such as in lake and river sediments. It is known that highly polychlorinated biphenyl (PCB) congeners, for example, are susceptible to reductive dehalo-genation, the result of the interaction of syn-trophic microbial communities that are active under methanogenic and sulfate-reducing... 

Some carcinogens are inactive in microbial assay systems because they require metabolic activation by mammalian enzymes to the ultimate active form. This activation can be duplicated, to some extent, by incorporating into the microbial system cell-free extracts derived from mammalian tissues. A convenient source is the liver of rats induced with the polychlorinated biphenyl Aroclor 1254. 

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