Trisodium 4-[[1-hydroxy-6-[[[[5-hydroxy-6-(phenylazo)-7-sulphonato-2-naphthyl]amino]carbonyl]amino]-3-sulphonato-2-naphthyl]azo]benzoate

Endpoint summary

Description of key information

Biodegradation in water:

Biodegradability of test chemical Trisodium 4-[[1-hydroxy-6-[[[[5-hydroxy-6-(phenylazo)-7-sulphonato-2-naphthyl]amino]carbonyl]amino]-3-sulphonato-2-naphthyl]azo]benzoate ( CAS no. 6598 -63 -6) was predicted by using OECD QSAR tool box v3.3 using log Kow as primary descriptor. The test chemical Trisodium 4-[[1-hydroxy-6-[[[[5-hydroxy-6-(phenylazo)-7-sulphonato-2-naphthyl]amino]carbonyl]amino]-3-sulphonato-2-naphthyl]azo]benzoate showed 0.14 % biodegradation by considering BOD as parameter and microorganisms as inoculum in 28 days. Based on Percent biodegradability it is concluded that this test chemical is not readily biodegradable.

Biodegradation in water and sediments:

Estimation Programs Interface (EPI Suite, 2017) prediction model was run to predict the half-life in water and sediment for the test compound  Trisodium 4-[[1-hydroxy-6-[[[[5-hydroxy-6-(phenylazo)-7-sulphonato-2-naphthyl]amino]carbonyl]amino]-3-sulphonato-2-naphthyl]azo]benzoate (CAS No: 6598-63-6). If released in to the environment, 0.577 % of the chemical will partition into water according to the Mackay fugacity model level III and the half-life period of test chemical Trisodium 4-[[1-hydroxy-6-[[[[5-hydroxy-6-(phenylazo)-7-sulphonato-2-naphthyl]amino]carbonyl]amino]-3-sulphonato-2-naphthyl]azo]benzoate in water is estimated to be 180 days ( 4320 hrs). The half-life (180 days estimated by EPI suite) indicates that the chemical is persistent in waterand the exposure risk to aquatic animals is high whereas the half-life period of Trisodium 4-[[1-hydroxy-6-[[[[5-hydroxy-6-(phenylazo)-7-sulphonato-2-naphthyl]amino]carbonyl]amino]-3-sulphonato-2-naphthyl]azo]benzoate in sediment is estimated to be 1620.833 days (38900 hrs). Based on this half-life value, it indicates that test chemical Trisodium 4-[[1-hydroxy-6-[[[[5-hydroxy-6-(phenylazo)-7-sulphonato-2-naphthyl]amino]carbonyl]amino]-3-sulphonato-2-naphthyl]azo]benzoate is persistent in sediment.

Biodegradation in Soil:

The half-life period of Trisodium 4-[[1-hydroxy-6-[[[[5-hydroxy-6-(phenylazo)-7-sulphonato-2-naphthyl]amino]carbonyl]amino]-3-sulphonato-2-naphthyl]azo]benzoate (CAS No: 6598 -63 -6) in soil was estimated using Level III Fugacity Model by EPI Suite version 4.1 estimation database (EPI suite, 2017). If released into the environment, 52.5 % of the chemical will partition into soil according to the Mackay fugacity model level III. The half-life period of test chemical Trisodium 4-[[1-hydroxy-6-[[[[5-hydroxy-6-(phenylazo)-7-sulphonato-2-naphthyl]amino]carbonyl]amino]-3-sulphonato-2-naphthyl]azo]benzoatein soil is estimated to be 360 days (8640 hrs). Based on this half-life value of test chemical Trisodium 4-[[1-hydroxy-6-[[[[5-hydroxy-6-(phenylazo)-7-sulphonato-2-naphthyl]amino]carbonyl]amino] -3-sulphonato-2-naphthyl] azo]benzoate, it is concluded that the chemical is persistent in the soil environment and the exposure risk to soil dwelling animals is high.

Additional information

Biodegradation in water:

Predicted data for target compound Trisodium 4-[[1-hydroxy-6-[[[[5-hydroxy-6-(phenylazo)-7-sulphonato-2-naphthyl]amino]carbonyl]amino]-3-sulphonato-2-naphthyl] azo]benzoate (CAS no. 6598 -63 -6) and supporting weight of evidence studies for its closest read across chemicals with log Kow as a primary descriptor were reviewed for the biodegradation endpoint which are summarized as below.

In first predicted data study the biodegradability of test chemical Trisodium 4-[[1-hydroxy-6-[[[[5-hydroxy-6-(phenylazo)-7-sulphonato-2-naphthyl]amino]carbonyl]amino]-3-sulphonato-2-naphthyl]azo]benzoate was estimated by using OECD QSAR tool box v3.3 using log Kow as primary descriptor. The test chemical Trisodium 4-[[1-hydroxy-6-[[[[5-hydroxy-6-(phenylazo)-7-sulphonato-2-naphthyl]amino]carbonyl]amino]-3-sulphonato-2-naphthyl]azo]benzoate showed 0.14 % biodegradation by considering BOD as parameter and microorganisms as inoculum in 28 days. Based on Percent biodegradability it is concluded that this test chemical is not readily biodegradable.

 

Next weight of evidence study was done by using Estimation Programs Interface Suite (EPI suite, 2017) to estimate the biodegradation potential of the test chemicalTrisodium 4-[[1-hydroxy-6-[[[[5-hydroxy-6-(phenylazo)-7-sulphonato-2-naphthyl]amino]carbonyl]amino]-3-sulphonato-2-naphthyl]azo]benzoate in the presence of mixed populations of environmental microorganisms. The biodegradability of the substance was calculated using seven different models such as Linear Model, Non-Linear Model, Ultimate Biodegradation Timeframe, Primary Biodegradation Timeframe, MITI Linear Model, MITI Non-Linear Model and Anaerobic Model (called as Biowin 1-7, respectively) of the BIOWIN v4.10 software. The results indicate that chemical Trisodium 4-[[1-hydroxy-6-[[[[5-hydroxy-6-(phenylazo)-7-sulphonato-2-naphthyl]amino]carbonyl]amino]-3-sulphonato-2-naphthyl]azo]benzoateis not readily biodegradable.

 

The supporting weight of evidence study was done from authoritative database (J Check, 2017) for tread across chemical disodium 4-amino-3-[(E)-2-(4-{4-[(E)-2-(2,4-diaminophenyl)diazen-1-yl]phenyl}phenyl)diazen-1-yl]-5-hydroxy-6-[(E)-2-phenyldiazen-1-yl]naphthalene-2,7-disulfonate (CAS no. 1937-37-7). In this study the read across chemical was subjected to biodegradation test by taking activated sludge as inoculums at 30 mg/L concentration. Biodegradation was analysed by using BOD, TOC and HPLC parameters. The initial concentration of read across chemical was 100 mg/L. The study design used was of standard type. The read across chemical disodium 4-amino-3-[(E)-2-(4-{4-[(E)-2-(2,4-diaminophenyl)diazen-1-yl]phenyl}phenyl)diazen-1-yl]-5-hydroxy-6-[(E)-2-phenyldiazen-1-yl]naphthalene- 2,7-disulfonate showed 0 % biodegradation by all three parameters namely BOD, TOC and HPLC parameter in 28 days. Based on percent biodegradability it is concluded that read across chemical disodium 4-amino-3-[(E)-2-(4-{4-[(E)-2-(2,4-diaminophenyl)diazen-1-yl]phenyl}phenyl)diazen-1-yl]-5-hydroxy-6-[(E)-2-phenyldiazen-1-yl] naphthalene-2,7-disulfonate is not readily biodegradable.

 

Similarly another supporting weight of evidence study was also done from same source as mentione d above (J check, 2017) for another read across chemical tetrasodium 3,3'-[carbonylbis[imino(2-methyl-4,1-phenylene)azo]]bisnaphthalene-1,5-disulphonate (CAS no. 3214-47-9). In this study the read across chemical was subjected to biodegradation test by taking sludge as inoculums at 30 mg/L concentration. Biodegradation was analysed by using BOD, TOC and HPLC parameters. The initial concentration of read across chemical was 100 mg/L and study design was of standard type. The read across chemical tetrasodium 3,3'-[carbonylbis[imino(2-methyl-4,1-phenylene)azo]]bisnaphthalene-1,5-disulphonateshowed 13 % biodegradation by TOC parameter and 0 % biodegradation by other two parameters namely BOD and HPLC in 28 days. Based on percent biodegradability it is concluded that read across chemical tetrasodium 3,3'-[carbonylbis[imino(2-methyl-4,1-phenylene)azo]]bisnaphthalene-1,5-disulphonate is not readily biodegradable.

 

On the basis of above results for target chemical Trisodium 4-[[1-hydroxy-6-[[[[5-hydroxy-6-(phenylazo)-7-sulphonato-2-naphthyl]amino]carbonyl]amino]-3-sulphonato -2-naphthyl]azo]benzoate ( CAS no. 6598 -63 -6) from ( EPI suite 2017 and OECD QSAR tool box v3.3 2017) and for its read across substances ( from authoritative database) the target chemical Trisodium 4-[[1-hydroxy-6-[[[[5-hydroxy-6-(phenylazo)-7-sulphonato-2-naphthyl]amino]carbonyl]amino]-3-sulphonato-2-naphthyl]azo]benzoatecan be expected to be not readily biodegradable.

Biodegradation in water and sediments:

Estimation Programs Interface (EPI Suite, 2017) prediction model was run to predict the half-life in water and sediment for the test compound  Trisodium 4-[[1-hydroxy-6-[[[[5-hydroxy-6-(phenylazo)-7-sulphonato-2-naphthyl]amino]carbonyl]amino]-3-sulphonato-2-naphthyl]azo]benzoate (CAS No: 6598-63-6). If released in to the environment, 0.577 % of the chemical will partition into water according to the Mackay fugacity model level III and the half-life period of test chemical Trisodium 4-[[1-hydroxy-6-[[[[5-hydroxy-6-(phenylazo)-7-sulphonato-2-naphthyl]amino]carbonyl]amino]-3-sulphonato-2-naphthyl]azo]benzoate in water is estimated to be 180 days ( 4320 hrs). The half-life (180 days estimated by EPI suite) indicates that the chemical is persistent in waterand the exposure risk to aquatic animals is high whereas the half-life period of Trisodium 4-[[1-hydroxy-6-[[[[5-hydroxy-6-(phenylazo)-7-sulphonato-2-naphthyl]amino]carbonyl]amino]-3-sulphonato-2-naphthyl]azo]benzoate in sediment is estimated to be 1620.833 days (38900 hrs). Based on this half-life value, it indicates that test chemical Trisodium 4-[[1-hydroxy-6-[[[[5-hydroxy-6-(phenylazo)-7-sulphonato-2-naphthyl]amino]carbonyl]amino]-3-sulphonato-2-naphthyl]azo]benzoate is persistent in sediment.

Biodegradation in Soil:

The half-life period of Trisodium 4-[[1-hydroxy-6-[[[[5-hydroxy-6-(phenylazo)-7-sulphonato-2-naphthyl]amino]carbonyl]amino]-3-sulphonato-2-naphthyl]azo]benzoate (CAS No: 6598 -63 -6) in soil was estimated using Level III Fugacity Model by EPI Suite version 4.1 estimation database (EPI suite, 2017). If released into the environment, 52.5 % of the chemical will partition into soil according to the Mackay fugacity model level III. The half-life period of test chemical Trisodium 4-[[1-hydroxy-6-[[[[5-hydroxy-6-(phenylazo)-7-sulphonato-2-naphthyl]amino]carbonyl]amino]-3-sulphonato-2-naphthyl]azo]benzoatein soil is estimated to be 360 days (8640 hrs). Based on this half-life value of test chemical Trisodium 4-[[1-hydroxy-6-[[[[5-hydroxy-6-(phenylazo)-7-sulphonato-2-naphthyl]amino]carbonyl]amino] -3-sulphonato-2-naphthyl] azo]benzoate, it is concluded that the chemical is persistent in the soil environment and the exposure risk to soil dwelling animals is high.