2-Naphthalenesulfonic acid, 7-amino-4-hydroxy-3-[2-[4-[[2-(sulfooxy)ethyl]sulfonyl]phenyl]diazenyl]-8-[2-[2-sulfo-4-[[2-(sulfooxy)ethyl]sulfonyl]phenyl]diazenyl]-, sodium salt (1:4)

Endpoint summary

Description of key information

Short term toxicity to fish:

1. Based on mortality of fishes due to the exposure of test chemical at nominal concentration 100 mg/l, experimental median lethal Concentrations [LC-50 (96 h)] on Zebra fish(Danio rerio) was determine to be > 100 mg/l.

2. Based on mortality of fishes due to the exposure of test chemical at nominal concentration 100 mg/l, experimental median lethal Concentrations [LC-50 (96 h)] on Zebra fish (Danio rerio) was determine to be > 100 mg/l.

Thus based on the above studies, 2-Naphthalenesulfonic acid, 7-amino-4-hydroxy-3-[2-[4-[[2-(sulfooxy)ethyl]sulfonyl]phenyl]diazenyl]-8-[2-[2-sulfo-4-[[2-(sulfooxy)ethyl]sulfonyl] phenyl]diazenyl]-, sodium salt (1:4) (CAS no 607724 -37 -8) consider to be nontoxic to fish and not classified as per the CLP classification criteria.

Short term toxicity to aquatic invertebrates:

1. Based on the immobility of daphnia magna, the median effective concentration (EC50) for the test substance, in Daphnia magna was determined to be > 900 mg/L for immobilisation effects.

2. Based on the immobility of daphnia magna due to the test chemical, the inhibitory concentration at which only 8% immobility observed was 100 mg/l in a 48 hour study.

3. The effective concentration (EC8) for the test substance, in Daphnia magna was determined to be 100 mg/L on the basis of mobiity inhibition effects in a 48 hour study.

Thus based on the above studies, 2-Naphthalenesulfonic acid, 7-amino-4-hydroxy-3-[2-[4-[[2-(sulfooxy)ethyl]sulfonyl]phenyl]diazenyl]-8-[2-[2-sulfo-4-[[2-(sulfooxy)ethyl]sulfonyl]phenyl]diazenyl]-, sodium salt (1:4) consider to be nontoxic and not classified as per the CLP classification criteria.

Toxicity to aquatic algae and cyanobacteria:

1. After 72 hours of exposure with test chemical to various nominal test concentration on aquatic algae, EC50 calculated from equation through probit analysis was determine to be > 200 mg/l.

2. Based on the growth rate inhibition of test organism Desmodesmus subspicatus (previous name: Scenedesmus subspicatus) due to the test chemical, the effect concentration ErC50 was determine at 76.8 mg/l.

3. The median effective concentration (EC50) for the test substance, in Desmodesmus subspicatus was determined to be 285.8 mg/L on the basis of effects on growth rate in a 72 hour study.

Based on all three studies chemical consider to be nontoxic.

Toxicity to microorganisms:

1. This investigation was aimed at identifying the effects of the test chemical and its degradation products on microbial growth. Test chemical and its degradation products were not toxic to Aspergillus ochraceus and Penicillium ochrochloron MTCC 517 at 1,000 ppm concentration.

2. The death rate of the test organism at 10000mg/l was 77.4%. Therefore the Effective concentration causing more than 50% death of Paramecium caudatum is reported as 10000 mg/l

Additional information

Summarized result of toxicity of the chemical 2-Naphthalenesulfonic acid, 7-amino-4-hydroxy-3-[2-[4-[[2-(sulfooxy)ethyl]sulfonyl] phenyl]diazenyl]-8-[2-[2-sulfo-4-[[2-(sulfooxy)ethyl]sulfonyl]phenyl] diazenyl]-, sodium salt (1:4) (CAS no 607724 -37 -8) on the growth of fishes, aquatic invertebrates and algae and microorganisms was studied by considering and collecting the data from various databases for target chemical. The studies are as follows:  

Short term toxicity to fish:

Various studies available for the test chemical were reviewed to determine the toxic nature of 2-Naphthalenesulfonic acid, 7-amino-4-hydroxy-3-[2-[4-[[2-(sulfooxy)ethyl]sulfonyl] phenyl]diazenyl]-8-[2-[2-sulfo-4-[[2-(sulfooxy)ethyl]sulfonyl]phenyl]diazenyl]-, sodium salt (1:4) (CAS no 607724 -37 -8) on the mortality of fish. The studies are as mentioned below:

 

In the first study Fish Acute Toxicity test was performed to evaluate the toxic nature of test chemical. Test was performed according to OECD Guideline 203. The test substance was poorly soluble in water. Therefore, the test solution was prepared by dissolving 400 mg of the test substance in 4 liters of potable water (passed through reverse osmosis system) with 48 hr stirring for achieving test concentrations of 100mg/L , respectively. The test was performed on the limit concentration i.e nominal concentration selected for the experiment were 100 mg/L and test fish were exposed to these concentration for 96 hours. After 96hrs of exposure LC0, LC50 and LC100 was observed. Effect on the symptoms and the normal activity was checked in the interval of 24rs. pH, temperature and dissolved oxygen was also checked. The lethal concentrations LC50 was determine to be >100 mg/L. LC0 (96 hours) (highest loading at which no mortality was observed) = 100 mg/L. LC50 (96 hours) Experimental = >100 mg/L. Thus based on the LC50 it can be concluded that the chemical was nontoxic and can be consider to be not classified as per the CLP classification criteria.

 

Similarly Fish Acute Toxicity test according to OECD Guideline 203 was conducted for test chemical. The test substance was soluble in water. Therefore, the test solution was prepared by dissolving 400 mg of the test substance in 4 liters of potable water (passed through reverse osmosis system) with 2 hrs continuous stirring for achieving test concentrations of 100mg/L, respectively. The test was performed on the limit concentration i.e nominal concentration selected for the experiment were 100 mg/L and test fish were exposed to these concentration for 96 hours. After 96hrs of exposure LC0, LC50 and LC100 was observed. Effect on the symptoms and the normal activity was checked in the interval of 24rs. pH, temperature and dissolved oxygen was also checked. The lethal concentrations LC50 was determine to be >100 mg/L. LC0 (96 hours) (highest loading at which no mortality was observed) = 100 mg/L. LC50 (96 hours) Experimental = >100 mg/L. Thus based on the LC50 it can be concluded that the chemical was nontoxic to fish and can be consider to be not classified as per the CLP classification criteria.

 

Thus based on the above studies, 2-Naphthalenesulfonic acid, 7-amino-4-hydroxy-3-[2-[4-[[2-(sulfooxy)ethyl]sulfonyl]phenyl]diazenyl]-8-[2-[2-sulfo-4-[[2-(sulfooxy)ethyl]sulfonyl] phenyl]diazenyl]-, sodium salt (1:4) (CAS no 607724 -37 -8) consider to be nontoxic to fish and not classified as per the CLP classification criteria.

 

 

Short term toxicity to aquatic invertebrates:

Various studies available for the test chemical were reviewed to determine the toxic nature of 2-Naphthalenesulfonic acid, 7-amino-4-hydroxy-3-[2-[4-[[2-(sulfooxy)ethyl]sulfonyl]phenyl]diazenyl]-8-[2-[2-sulfo-4-[[2-(sulfooxy)ethyl]sulfonyl]phenyl]diazenyl]-, sodium salt (1:4) (CAS no 607724 -37 -8) on the mobility of aquatic invertebrates. The studies are as mentioned below:

 

Aim of the first study from experimental report was to assess the effect of chemical on the mobility of daphnia magna. Test was conducted according to OECD Guideline 202. The stock solution 100 mg/l was prepared by dissolving red powder in reconstituted water. Test solutions of required concentration as were prepared by mixing the stock solution of the test sample with reconstituted test water. The test substance was tested at the 0, 5, 10, 20, 40, 80, 160 mg/l nominal concentration. Potassium dichromate (K2Cr2O7) were used as a reference positive control. Effects on immobilisation were observed for 48 hours by using non linear regression by the software Prism 4.0. After the exposure of chemical for 48 hrs 50 % immobility was observed. Based on the immobility of daphnia magna, the median effective concentration (EC50) for the test substance, in Daphnia magna was determined to be > 900 mg/L for immobilisation effects. This value indicates that the substance is likely to be non-hazardous to aquatic invertebrates and cannot be classified as toxic as per the CLP classification criteria.

 

Similarly in second study an acute immobilisation test was used to test how a range of concentrations of test chemical exerts different degrees of toxic effects on the swimming capability of Daphnia magna under otherwise identical test conditions. The test was performed in close resemblance to OECD guideline 202. The testing aim was to determine a EC50 after 48 hours of exposure to D. magna. Daphnids were exposed to test chemical in 50 ml beakers in a volume of 25 ml of liquid solution containing both the chemical and media as specified in OECD 202. The beakers were placed in a temperature controlled room at 20±1 degrees Celsius. The D. magna (age ≤24) used. The breeding stock of D. Magna originated from University of Technology in Prague. The animals were exposed to medium (i.e. a beaker containing only medium) and/or the tested chemical during 48 hours (±1 hour). None of the exposed animal’s immobilization were affected by exposure to only medium. The nominal concentrations used were: 100 mg/L (limit test). There were 5 Daphnia per test vessels and 5 replicates per concentration. The pH in test vessels were 7.7-7.8 mg/L. The positive control/ reference substance used in the tested showed an expected result and gave an EC50 that corresponded to previous exposures with this chemical in D. magna. The IC50 was defined as a concentration that immobilizes 50% of the exposed D. magna. Eight percent immobilization in D. magna was observed after 48 hours of exposure to 100 mg/L of test chemical. The IC8 was therefore estimated to be 100 mg/L. Based on the IC8, it can be concluded that the chemical was nontoxic and can be consider to be not classified as per CLP classification criteria.

 

Determination of the inhibition of the mobility of daphnids was carried out with the substance according to OECD Guideline 202. The limit test was performed at 100 mg/l. Effects on immobilisation were observed for 48 hours. The solution 100 mg/l was prepared by dissolving brown powder in reconstituted water. The effective concentration (EC8) for the test substance, in Daphnia magna was determined to be 100 mg/L on the basis of mobility inhibition effects in a 48 hour study. This value indicates that the substance is likely to be non-hazardous to aquatic invertebrates and cannot be classified as toxic as per the CLP criteria.

 

Thus based on the above studies, 2-Naphthalenesulfonic acid, 7-amino-4-hydroxy-3-[2-[4-[[2-(sulfooxy)ethyl]sulfonyl]phenyl]diazenyl]-8-[2-[2-sulfo-4-[[2-(sulfooxy)ethyl]sulfonyl]phenyl]diazenyl]-, sodium salt (1:4)(CAS no 607724 -37 -8) consider to be nontoxic and not classified as per the CLP classification criteria.

 

Toxicity to aquatic algae and cyanobacteria:

Various studies available for the test chemical including for read across chemicals were reviewed to determine the toxic nature of 2-Naphthalenesulfonic acid, 7-amino-4-hydroxy-3-[2-[4-[[2-(sulfooxy)ethyl]sulfonyl] phenyl]diazenyl]-8-[2-[2-sulfo-4-[[2-(sulfooxy)ethyl]sulfonyl]phenyl]diazenyl]-, sodium salt (1:4) (CAS no 607724 -37 -8) on the growth of algae and cyanobacteria. The studies are as mentioned below:

 

In the first key study from experimental report the effect of test item was studied on the growth of fresh water green alga Chlorella 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, 200mg/L. The test solution was prepared in aseptic condition. The test item was prepared by adding 50 mg of test item in 250 ml of BBM to get the final concentration of 200 mg/L. This stock solution was kept for stirring/sonication for 30 minutes to obtain a homogenous solution for the experiment. The test concentrations were chosen according to the available data of the test item. The concentrations chosen were set up to the water solubility limit. The remaining test solutions were prepared by dilution from the above stock solution. To have a better growth and visibility of cells, the initial of the culture was kept 1 X 10000cells/ml. Care was taken to have a homogeneous solution for the experiment. Test was performed in static manner at proper requirement of pH and temperature. The microscopic observations were noted down in each of the control vessel. All the cells appeared healthy, round and green throughout the study duration in the control. Also, the drift in pH in the control vessels did not increase by >1.5 units when observed on 72 hours as compared to 0 hours. The average pH drift observed in the control vessels was 0 units. After 72 hours of exposure with test chemical to various nominal test concentration on aquatic algae, EC50 calculated from equation through probit analysis was determine to be > 200 mg/l. Based on the EC50, it can be concluded that the chemical was nontoxic and can be consider to be not classified as toxic as per the CLP classification criteria.

 

 

Similarly in second weight of evidence study short term toxicity study of test substance to aquatic algae Desmodesmus subspicatus (previous name: Scenedesmus subspicatus) was conducted for 72 hrs. Test was performed according to the 201 OECD guideline in a static system. The stock solution 100 mg/l was prepared by dissolving black powder in OECD growth medium. Test solutions of required concentration were prepared by mixing the stock solution of the test sample with OECD growth medium and inoculum culture and tested at the 0, 12, 20, 35, 60, 100 mg/l nominal concentrations. Effects on the growth rate of the organism were studied. Potassium dichromate (K2Cr2O7) were used as a reference positive control. Effects on growth rate were observed for 72 hours by using non linear regression by the software Prism 4.0. Based on the growth rate inhibition of test organism Desmodesmus subspicatus (previous name: Scenedesmus subspicatus) due to the chemical, the effect concentration ErC50 was 76.8 mg/l. This value indicates that the substance is likely to be hazardous to aquatic algae and can be classified as aquatic chronic 3 as per the CLP criteria. But as the test chemical was readily biodegradable in water so, on that basis chemical was consider as nontoxic and can be consider to be not classified as per the CLP classification criteria.

 

 

Freshwater algal growth inhibition test was carried out on Desmodesmus subspicatus with the test substance according to OECD Guideline 201. The stock solution 100 mg/l was prepared by dissolving red powder in OECD growth medium. The solution was kept 30 min in ultrasonic bath. Test solutions of required concentration were prepared by mixing the stock solution of the test sample with OECD growth medium and inoculum culture. 5x10(3) cells /ml algal culture were use in the study for total exposure period of 72hrs. Test conducted in 50 ml glass vessel filled with 50 ml of sample volume and tested at the concentrations 0, 0, 20, 30, 45, 67, 100 mg/l. Effects on the growth rate of the organism were studied. The median effective concentration (ErC50) for the test substance, in Desmodesmus subspicatus was determined to be 285.8 mg/L. This value indicates that the substance is likely to be non-hazardous to aquatic algae and cannot be classified as toxic as per the CLP criteria.

 

Thus based on the above studies, 2-Naphthalenesulfonic acid, 7-amino-4-hydroxy-3-[2-[4-[[2-(sulfooxy)ethyl]sulfonyl]phenyl]diazenyl]-8-[2-[2-sulfo-4-[[2-(sulfooxy)ethyl]sulfonyl] phenyl]diazenyl]-, sodium salt (1:4) (CAS no 607724 -37 -8) consider to be nontoxic and not classified as per the CLP classification criteria.

 

Toxicity to microorganisms:

Various studies available for the test chemical were reviewed to determine the toxic nature of 2-Naphthalenesulfonic acid, 7-amino-4-hydroxy-3-[2-[4-[[2-(sulfooxy)ethyl]sulfonyl] phenyl]diazenyl]-8-[2-[2-sulfo-4-[[2-(sulfooxy)ethyl]sulfonyl]phenyl]diazenyl]-, sodium salt (1:4) (CAS no 607724 -37 -8) on the growth of microorganisms. The studies are as mentioned below:

 

In the first study, this investigation was aimed at identifying the effects of the test chemical and its degradation products on microbial growth. Test chemical was purchased from Hi-media Laboratories Pvt. Ltd., Mumbai, India. Aspergillus ochraceus NCIM 1146 was obtained from National Chemical Laboratory, Pune, India. E. coli MTCC 452, B. subtilis MTCC 6910 and Penicillium ochrochloron MTCC 517 were obtained from Microbial Type Culture Collection and Gene Bank (MTCC), Institute of Microbial Technology, Chandigarh, India. It was regularly maintained and preserved at 4°C on nutrient agar slants contained in (g/l); bacteriological peptone 10.0, beef extract 10.0 and NaCl 5.0 Microbial toxicity of control and metabolites obtained after its decolorization (final concentration 1,000 ppm) was carried out in relation to E. coli, Bacillus substilis, Aspergillus ochraceus and Penicillium ochrochloron MTCC 517 and zone of inhibition (diameter in mm) was recorded. The diameter of the discs used was 10mm. Test chemical and its degradation products were not toxic to Aspergillus ochraceus and Penicillium ochrochloron MTCC 517 at 1,000 ppm concentration.

 

Similarly in the second study from peer reviewed journal the death of Paramecium caudatum (PC), a unicellular animal, can be observed more readily and in far less time than that of small animals. Hence a bioassay was conducted to study the toxic effect of test chemical. Paramecium Caudatum was maintained at 22°C on 0.15 % dried lettuce infusion and fed with Aerobacter aerogenes. Chemical was tested in 0.1% and 1% concentration. The test concentrations were put in a hollow slide glass, and an equal volume of 0.04 M phosphate buffer, pH 7.0, was added. After 5 to 10 test organisms were added, their survival times were measured microscopically. Thirty to forty test organisms for each concentration were tested by the same method, and the mean survival time and the death rate were calculated. The survival time was defined as the time required until death was observed for each concentration. Death was assumed to have occurred when there was no movement. The death rate was defined as the percentage of deaths observed during 20 minutes. The mean survival time (in sec) of test organism Paramecium caudatum was determined to be 695 seconds.  The death rate of the test organism at 10000 mg/l was 77.4%. Therefore the Effective concentration causing more than 50% death of Paramecium caudatum was reported as 10000 mg/l.

 

Thus based on the above studies, 2-Naphthalenesulfonic acid, 7-amino-4-hydroxy-3-[2-[4-[[2-(sulfooxy)ethyl]sulfonyl]phenyl]diazenyl]-8-[2-[2-sulfo-4-[[2-(sulfooxy)ethyl]sulfonyl] phenyl]diazenyl]-, sodium salt (1:4) (CAS no 607724 -37 -8) consider to be nontoxic and not classified as per the CLP classification criteria.

 

Based on the overall studies for the toxicity on fish, invertebrates, algae and cyanobacteria, chemical consider to be nontoxic and not classified as per the CLP classification criteria.