title: A comparative study of biodegradability of a carcinogenic aromatic amine (4,4'-diaminodiphenylmethane) with OECD 301 test methods.
abstract: 4,4'-Diaminodiphenylmethane (MDA) is a widely used compound in industries. Studies on the biodegradability of MDA are necessary for environmental hazard identification and risk assessment. Previous studies have suggested that MDA was not readily biodegradable. In the present study, three batches of biodegradation tests (OECD 301A, B, D and F tests) were performed on MDA in June, August and December of 2012. MDA was found to be readily biodegradable and produced colored intermediates in the 301A, B and F test systems. MDA biodegradation measurements were consistent among the three batches of tests. Differences in the extent of biodegradation determined in different methods originated from different test conditions and assessment endpoints. The 301D test has stringent test conditions and is usually performed on chemicals that are toxic to microorganisms, so the test results obtained from 301D tests are less meaningful for evaluating the biodegradability of MDA. The low MDA biodegradation measurements in the 301B tests compared to the 301A and F tests were due to the assessment method, which did not account for MDA incorporation into biomass in its calculation of CO2 formation rate. The differences in the biodegradation rates, as measured by the different OECD 301 test systems, could also be related to the structure and properties of the chemical. For test substances that can be assessed by all OECD 301 test methods, the highest biodegradation values may be obtained from the 301A and F test methods. This study provides new information to assess the environmental fate in the risk assessment of MDA.
authors.affiliation: MOE Key Laboratory Aquatic Product Safety, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China; Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou 510070, China; State Key Laboratory of Applied Microbiology Southern China, Guangzhou 510070, China.
authors.forename: Cheng-Fang
authors.initials: CF
authors.lastname: Mei
authors.affiliation: Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou 510070, China; State Key Laboratory of Applied Microbiology Southern China, Guangzhou 510070, China.
authors.forename: Yan-Zhen
authors.initials: YZ
authors.lastname: Liu
authors.affiliation: Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou 510070, China; State Key Laboratory of Applied Microbiology Southern China, Guangzhou 510070, China.
authors.forename: Wei-Nian
authors.initials: WN
authors.lastname: Long
authors.affiliation: Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou 510070, China; State Key Laboratory of Applied Microbiology Southern China, Guangzhou 510070, China.
authors.forename: Guo-Ping
authors.initials: GP
authors.lastname: Sun
authors.affiliation: Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou 510070, China; State Key Laboratory of Applied Microbiology Southern China, Guangzhou 510070, China.
authors.forename: Guo-Qu
authors.initials: GQ
authors.lastname: Zeng
authors.affiliation: Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou 510070, China; State Key Laboratory of Applied Microbiology Southern China, Guangzhou 510070, China. Electronic address: xumy@gdim.cn.
authors.forename: Mei-Ying
authors.initials: MY
authors.lastname: Xu
authors.affiliation: MOE Key Laboratory Aquatic Product Safety, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China. Electronic address: cesltg@mail.sysu.edu.cn.
authors.forename: Tian-Gang
authors.initials: TG
authors.lastname: Luan
mesh_terms: D000814:Aniline Compounds / Q000378:metabolism*; D001673:Biodegradation, Environmental; D018533:Biomass; D002273:Carcinogens / Q000378:metabolism*; D066150:Organisation for Economic Co-Operation and Development; D018570:Risk Assessment; D001559:Benzhydryl Compounds
chemical_list: D000814:Aniline Compounds; D002273:Carcinogens; C009505:4,4'-diaminodiphenylmethane; D001559:Benzhydryl Compounds
keywords: 4,4′-Diaminodiphenylmethane; OECD 301 test; Ready biodegradability