Changes in mutagenicity of herbicide chlornitrofen during biodegradation.
We used the Ames assay to investigate changes in the mutagenicity of chlornitrofen during its aerobic biodegradation. Although a mixed culture of bacteria obtained from river water degraded chlornitrofen and reduced its concentration from 39 to 6 microg/l in 21 days, the indirect mutagenicity of the solution to Salmonella strains TA98, YG1021, and YG1026 increased gradually. This finding suggests that mutagenic metabolites were produced during the aerobic biodegradation. The increase in the mutagenicity was, however, much smaller under aerobic than under anaerobic conditions. The differing sensitivities of our test strains to the functional groups on the mutagens showed that the mutagenic metabolites were indirect frameshift-type mutagens that might have neither nitro nor amino groups.
Matsushita
Taku
T
Department of Civil Engineering, Gifu University, 1-1 Yanagido, 501-1193, Japan. taku_m@cc.gifu-u.ac.jp
Matsui
Yoshihiko
Y
Sakuma
Satoru
S
Inoue
Takanobu
T
D000332:Aerobiosis; D000818:Animals; D001421:Bacteria, Anaerobic / Q000378:metabolism*; D001673:Biodegradation, Environmental; D006540:Herbicides / Q000378:metabolism* / Q000633:toxicity*; D016296:Mutagenesis / Q000187:drug effects; D009152:Mutagenicity Tests; D009153:Mutagens / Q000378:metabolism*; D010647:Phenyl Ethers / Q000378:metabolism* / Q000633:toxicity*; D051381:Rats; D012475:Salmonella / Q000187:drug effects; D014874:Water Pollutants, Chemical / Q000378:metabolism / Q000633:toxicity
D006540:Herbicides; D009153:Mutagens; D010647:Phenyl Ethers; D014874:Water Pollutants, Chemical; C010422:2,4,6-trichlorophenyl 4-nitrophenyl ether