Disodium 2-amino-5-[(4-sulphonatophenyl)azo]benzenesulphonate

Endpoint summary

Description of key information

Short-term toxicity to fish:

Short term aquatic toxic effects of the test compound disodium 2-amino-5-[(4-sulphonatophenyl)azo]benzenesulphonate was predicted (predicted model ECOSAR Version 1.10). The study was based on the effects of the test compound on the fish in 96 hrs duration in a fresh water system. The predicted data suggests the lethal concentration (LC50) on the basis of mortality to be 121000 mg/L. This value concluded that the test compound disodium 2-amino-5-[(4-sulphonatophenyl)azo]benzenesulphonate does not exhibit short term toxicity to fish and is non hazardous to the aquatic environment.

Short term toxicity to aquatic invertebrates:

Aim of the study was to determine the short term toxicity of disodium 2-amino-5-[(4-sulfonatophenyl)diazenyl]benzenesulfonate (2706 -28 -7) to aquatic invertebrates by performing test according to the OECD guideline in a static system. The stock solution 100 mg/l was prepared by dissolving yellow powder in reconstituted water. Effects on immobilisation were observed for 48 hours. With the test substance one positive control Potassium dichromate (K2Cr2O7) was also run simultaneously. After the exposure of chemical, effect concentration EC50 was calculated using nonlinear regression by the software Prism 4.0. 25 daphnia magna were used in the study, out of that only 1 daphnia magna shows immobility and the remaining were mobile. The inhibitory concentration (I4) for the test substance Disodium 2-amino-5-[(4-sulphonatophenyl)azo]benzenesulphonate (Synonym of C.I. Acid Yellow 9), in Daphnia magna was determined to be 100 mg/L on the basis of mobiity inhibition effects in a 48 hour study. Only 4% inhibition was determine after 48 hrs of exposure. Based on the inhibitory concentration chemical was consider as nontoxic and not classified as per the CLP classification criteria.

Toxicity to aquatic algae:

Aim of this study was to evaluate the nature of chemical disodium 2-amino-5-[(4-sulfonatophenyl)diazenyl]benzenesulfonate (C.I. Acid Yellow 9) when comes in contact with the test organism Desmodesmus subspicatus (previous name: Scenedesmus subspicatus). Test was conducted according to the OECD guideline 201. The test solution 100 mg/l was prepared by dissolving yellow powder in OECD growth medium. Effects on the growth rate of the organism were studied. Based on the growth rate inhibition of algae Desmodesmus subspicatus (previous name: Scenedesmus subspicatus) due to the exposure of chemical disodium 2-amino-5-[(4-sulfonatophenyl) diazenyl]benzenesulfonate (C.I. Acid Yellow 9), the inhibitory concentration was 100 mg/l on that only 1.6 % inhibition was observed after the 72hrs incubation period. This value indicates that the substance is likely to be non-hazardous to aquatic algae and cannot be classified as per the CLP classification criteria.

Toxicity to microorganisms:

In toxicity to micro organism the effective concentration i.e EC0 value for test substance  Disodium 2-amino-5-[(4-sulphonatophenyl)azo]benzenesulphonate (2706-28-7) was found to be 5000 mg/l on Pseudomonas fluorescens by the method BringmannKühnTest for 24 hrs.

Additional information

Short-term toxicity to fish:

Short term toxicity to fish was assessed for the target compound disodium 2-amino-5-[(4-sulphonatophenyl)azo]benzenesulphonate (CAS no 2706-28-7) and its related read- across by reviewing a number of studies. The summary of the results are presented below:

Short term aquatic toxic effects of the test compound disodium 2-amino-5-[(4-sulphonatophenyl)azo]benzenesulphonate was predicted (predicted model ECOSAR Version 1.10). The study was based on the effects of the test compound on the fish in 96 hrs duration in a fresh water system. The predicted data suggests the lethal concentration (LC50) on the basis of mortality to be 121000 mg/L. This value concluded that the test compound disodium 2-amino-5-[(4-sulphonatophenyl)azo]benzenesulphonate does not exhibit short term toxicity to fish and is non hazardous to the aquatic environment.

Whereas experimental study (Chemophere. Vol. 28, No. 12, pp. 2203.2236, 1994) for read across substance 2,2'-(1,2-Ethenediyl)bis(5-aminobenzenesulfonic acid) disodium salt (Cas no. 7336-20-1)indicate that the lethal concentrations i.e LC0 of test substance for fish Leuciscus idus, Bruchydunio rerio,Salmo gaidneri, Pimephales promelas, Lepomis macrochirus, Poecilia reticulate was found to be >1000 mg/l respectively for 72 hrs.

And other experimental study for read across Sodium 4,4'-diaminostilbene-2,2'-disulphonate (Cas no. 25394-13-2)indicate that the lethal concentration i.e LC50 of test substance on fish was found to be >200 mg/l for 48 hrs.( Data bank of Environmental Properties of Chemicals (EnviChem), 2016.)

Based on above available studies for target chemical and its read across it is concluded that the substance disodium 2-amino-5-[(4-sulphonatophenyl)azo]benzenesulphonate (CAS no 2706-28-7) not qualify for the aquatic classification as per the CLP criteria.

Short term toxicity to aquatic invertebrates:

Summarized result for the toxicity of chemical disodium 2-amino-5-[(4-sulfonatophenyl)diazenyl]benzenesulfonate on the growth and mobility of aquatic invertebrates daphnia magna which are as follows:

In the first key study for the target chemical disodium 2-amino-5-[(4-sulfonatophenyl)diazenyl]benzenesulfonate (2706 -28 -7) from ABITEC report 2017, toxicity was measured. Aim of the study was to determine the short term toxicity of disodium 2-amino-5-[(4-sulfonatophenyl)diazenyl]benzenesulfonate (2706 -28 -7) to aquatic invertebrates by performing test according to the OECD guideline in a static system. The stock solution 100 mg/l was prepared by dissolving yellow powder in reconstituted water. Effects on immobilisation were observed for 48 hours. With the test substance one positive control Potassium dichromate (K2Cr2O7) was also run simultaneously. After the exposure of chemical, effect concentration EC50 was calculated using nonlinear regression by the software Prism 4.0. 25 daphnia magna were used in the study, out of that only 1 daphnia magna shows immobility and the remaining were mobile. The inhibitory concentration (I4) for the test substance Disodium 2-amino-5-[(4-sulphonatophenyl)azo]benzenesulphonate (Synonym of C.I. Acid Yellow 9), in Daphnia magna was determined to be 100 mg/L on the basis of mobiity inhibition effects in a 48 hour study. Only 4% inhibition was determine after 48 hrs of exposure. Based on the inhibitory concentration chemical was consider as nontoxic and not classified as per the CLP classification criteria.

Similarly first study was supported by the second supporting study from the GSBL database for the target chemical disodium 2-amino-5-[(4-sulfonatophenyl)diazenyl]benzenesulfonate (2706 -28 -7). Short term toxicity to aquatic invertebrates by Disodium 2-amino-5-[(4-sulphonatophenyl)azo]benzenesulphonate was performed on Daphnia Magna for 48 hrs at 1000 mg/l concentration.After experiment it was observed that the EC 0 value for Disodium 2-amino-5-[(4-sulphonatophenyl)azo]benzenesulphonate (2708-28-7) to Daphnia magna was determined to be 1000 mg/l on the basis of mortality, mobility and cell proliferation inhibition. Based on the result, Disodium 2-amino-5-[(4-sulphonatophenyl)azo]benzenesulphonate was considered as not Classified as per CLP regulations.

Based on the above studies chemical was consider as nontoxic and not classified as per the CLP classification criteria.

Toxicity to aquatic algae:

Summarized result for the toxicity of chemical disodium 2-amino-5-[(4-sulfonatophenyl)diazenyl]benzenesulfonate on the growth of aquatic algae which are as follows:

In the first key study for the target chemical disodium 2-amino-5-[(4-sulfonatophenyl)diazenyl]benzenesulfonate (2706 -28 -7) from ABITEC report 2017, toxicity was measured.

Aim of this study was to evaluate the nature of chemical disodium 2-amino-5-[(4-sulfonatophenyl)diazenyl]benzenesulfonate (C.I. Acid Yellow 9) when comes in contact with the test organism Desmodesmus subspicatus (previous name: Scenedesmus subspicatus). Test was conducted according to the OECD guideline 201. The test solution 100 mg/l was prepared by dissolving yellow powder in OECD growth medium. Effects on the growth rate of the organism were studied. Based on the growth rate inhibition of algae Desmodesmus subspicatus (previous name: Scenedesmus subspicatus) due to the exposure of chemical disodium 2-amino-5-[(4-sulfonatophenyl) diazenyl]benzenesulfonate (C.I. Acid Yellow 9), the inhibitory concentration was 100 mg/l on that only 1.6 % inhibition was observed after the 72hrs incubation period. This value indicates that the substance is likely to be non-hazardous to aquatic algae and cannot be classified as per the CLP classification criteria.

Similarly first study was supported by the second supporting study from the UERL report for the target chemical disodium 2-amino-5-[(4-sulfonatophenyl)diazenyl]benzenesulfonate (2706 -28 -7).

The effect of test item disodium 2-amino-5-[(4-sulphonatophenyl)azo]benzenesulphonate, (CAS No. 2706-28-7) was studied on the growth of fresh water green algaChlorella vulgaris.The study was conducted following OECD guideline 201- Alga, growth inhibition test. The test concentration chosen for the study were 6.25mg/L, 12.5mg/L, 25mg/L, 50mg/L, 100mg/L and 200mg/L. The test concentrations were prepared using stock solution of the test item using mineral media. The green alga was exposed to the test concentration for a period of 72 hours to observe average specific growth rate and % growth inhibition under the effect of the test item. EC25 calculated graphically through probit analysis was observed to be 239.918mg/L and the EC50 value was determined to be > 200 mg/l, respectively. Thus, based on the EC50 value, test substance can be considered as non-toxic to aquatic organisms and thus cannot be classified as hazardous as per the CLP criteria.

Based on the above studies chemical was consider as nontoxic and not classified as per the CLP classification criteria.

Toxicity to microorganisms:

Toxicity to micro organism was assessed for the target compound Disodium 2-amino-5-[(4-sulphonatophenyl)azo]benzene sulphonate (2706-28-7) and its related read- across. The summary of the results are presented below:

In Toxicity to microorganism study for test substance Disodium 2-amino-5-[(4-sulphonatophenyl)azo]benzene sulphonate conducted according to Bringmann Kühn Test method on test species Pseudomonas fluorescens for 24 hrs.

During experiment the effective concentration i.e EC0 was found to be 5000 mg/l on the basis of mortality, swimming behaviour and Cell proliferation inhibition effects.

Whereas experimental study (Chemophere. Vol. 28, No. 12, pp. 2203.2236, 1994) for read across substance 2,2'-(1,2-Ethenediyl)bis(5-aminobenzenesulfonic acid) disodium salt (Cas no. 7336-20-1)indicate that the effect concentrations i.e EC0 of test substance for bacteria (unadapted biological waste water treatment plant) was found to be 1000 mg/l for 24 hrs.

And other experimental study report from HPVIS database for same read across substance i.e 2,2'-(1,2-Ethenediyl)bis(5-aminobenzenesulfonic acid) disodium salt (Cas no. 7336-20-1) indicate that the EC0 was found to be >300 mg/l and EC50 is >100 mg/l for 3 hrs.on Bacteria (activated sludge) and on the basis of growth inhibition effect. For 24 hrs on Pseudomonas fluorescens species effect concentration (EC0)was resulted as 1000 mg/l and Photobacterium phosphoreum species for 45 min study the EC50 was found to be >500 mg/l.

Based on above available studies it is concluded that the substance Disodium 2-amino-5-[(4-sulphonatophenyl)azo]benzene sulphonate (2706-28-7)was consider to be non toxic to micro organisms.