Studies on the toxicities of chlorinated nitrobiphenyl ethers to fish. III. Reduction of chlorinated nitrobiphenyl ethers by carp and rat intestinal microorganisms.

Abstract

The reduction of chlorinated nitrobiphenyl ethers and their nitroso derivatives, and the stability of their amino derivatives by carp and rat intestinal microorganisms were investigated. All the chlorinated nitrobiphenyl ethers used were reduced to teh corresponding amino derivatives by intestinal microorganisms of carp and rat under both aerobic and anaerobic conditions, The reduction rate of the clorinated nitrobiphenyl ethers was greater by rat intestinal micoorganisms than by carp intestinal microorganisms and was much faster under anaerobic condition than aerobic condition in both cases. Among the chlorinated nitrobiphenyl ethers, the reduction rate was the greatest of p-nitrobiphenyl ether followed by monochloro p-nitrobiphinyl ethers, 2, 4-dichloro p-nitrobiphenyl ether and then 2, 4, 6-trichloro p-nitrobiphenyl ether, and was dependent on the number of chlorine in the phenoxy group of the compounds. The amino derivatives except 4-chloro p-aminobiphenyl ether were stable with regard to intestinal microorganisms of both species. While, the nitroso derivatives were rapidly reduced to the amino derivatives by intestinal microorganisms.