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

Stability:

Hydrolysis:

According to annex VIII column 2 the study does not need to be conducted because the substance 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)is readily biodegradable.

Biodegradation:

Biodegradation in water:

Estimation Programs Interface Suite (EPI suite, 2018) was run to predict the biodegradation potential of the test compound 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 ) 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 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) is expected to be readily biodegradable.

Bioaccumulation:

Bioaccumulation: aquatic/sediments:

BCFBAF model (v3.01) of Estimation Programs Interface (EPI Suite, 2018) was used to predict the bioconcentration factor (BCF) of test 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 -87 -6). The bioconcentration factor (BCF) of test chemical was estimated to be 3.162 L/kg whole body w.w (at 25 deg C) which does not exceed the bioconcentration threshold of 2000, indicating that 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) is not expected to bioaccumulate in the food chain.

Transport and distribution:

Adsorption/desorption:

KOCWIN model (v2.00) of Estimation Programs Interface (EPI Suite, 2018) was used to predict the soil adsorption coefficient i.e Koc value of test 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). The soil adsorption coefficient i.e Koc value of test 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) was estimated to be 42200 L/kg (log Koc=4.623)  by means of MCI method (at 25 deg C). This Koc value indicates that the substance 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) has a very strong sorption to soil and sediment and therefore have negligible migration potential to ground water.

Additional information

Stability:

Hydrolysis:

According to annex VIII column 2 the study does not need to be conducted because the substance 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)is readily biodegradable.

Biodegradation:

Biodegradation in water:

Predicted data study for target 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 ) and supporting weight of evidence from study reports and journals for its structurally similar read across chemicals have been reviewed for biodegradation in water endpoint and their results are summarized below.

 

The first study was predicted data study in this study the Estimation Programs Interface Suite (EPI suite, 2018) was run to predict the biodegradation potential of the test compound 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 ) 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 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) is expected to be readily biodegradable.

 

Next study was experimental study reviewed from study report in this 28-days Closed Bottle test following the OECD guideline 301 D was performed to determine the ready biodegradability of the test item. The study was performed at a temperature of 20°C. The test system included control, test item and reference item. Polyseed were used for this study. 1 polyseed capsule were added in 500 ml D.I water and then stirred for 1 hour for proper mixing and functioning of inoculum. This gave the bacterial count as 10E7 to 10E8 CFU/ml. At the regular interval microbial plating was also performed on agar to confirm the vitality and CFU count of microorganism. The concentration of test and reference item (Sodium Benzoate) chosen for both the study was 4 mg/L, while that of inoculum was 32 ml/L . OECD mineral medium was used for the study. ThOD (Theoretical oxygen demand) of test and reference item was determined by calculation. % degradation was calculated using the values of BOD and ThOD for test item and reference item. The % degradation of procedure control (reference item) was also calculated using BOD & ThOD and was determined to be 76.5  %. Degradation of Sodium Benzoate exceeds 39.15 % on 7 days & 70.48 on 14th day. The activity of the inoculum is thus verified and the test can be considered as valid. The BOD28 value of test chemical was observed to be     1.05    mgO2/mg. ThOD was calculated as 1.08 mgO2/mg. Accordingly, the % degradation of the test item after 28 days of incubation at 20 ± 1°C according to Closed Bottle test was determined to be 97.22 %. Based on the results, the test item, under the test conditions, was considered to be readily in nature.

 

Another study was also reviewed from study report in this study the 28-days Closed Bottle test following the OECD guideline 301 D was performed to determine the ready biodegradability of the test chemical. The study was performed at a temperature of 20°C. The test system included control, test item and reference item. Polyseed were used for this study. 1 polyseed capsule were added in 500 ml D.I water and then stirred for 1 hour for proper mixing and functioning of inoculum. This gave the bacterial count as 10E7 to 10E8 CFU/ml. At the regular interval microbial plating was also performed on agar to confirm the vitality and CFU count of microorganism. The concentration of test and reference item (Sodium Benzoate) chosen for both the study was 4 mg/L, while that of inoculum was 32 ml/l. OECD mineral medium was used for the study. ThOD (Theoretical oxygen demand) of test and reference item was determined by calculation. % degradation was calculated using the values of BOD and ThOD for test item and reference item. The % degradation of procedure control (reference item) was also calculated using BOD & ThOD and was determined to be 75.3%. Degradation of Sodium Benzoate exceeds 46.38 % on 7 days & 61.44 % on 14th day. The activity of the inoculum is thus verified and the test can be considered as valid. The BOD28 value of test chemical was observed to be 1.1 mgO2/mg. ThOD was calculated as 1.2 mgO2/mg. Accordingly, the % degradation of the test item after 28 days of incubation at 20 ± 1°C according to Closed Bottle test was determined to be 91.66%. Based on the results, the test item, under the test conditions, was considered to be readily biodegradable in nature.

 

Last study was reviewed from Journal of Environmental Sciences (2007) in this study the Biodegradability of test substance was estimated using the Quantitative structure-biodegradability relationships (QSBRs).The QSBRs models include predictive model and mechanism-based QSBR model. With a total of four descriptors, molecular weight (MW), energies of the highest occupied molecular orbital (EHOMO), the lowest unoccupied molecular orbital (ELUMO), and the excited state (EES), calculated using quantum chemical semi-empirical methodology, a series of models were analyzed between the dye biodegradability and each descriptor. Out of these, three descriptors i.e, energies of the highest occupied molecular orbital (EHOMO), the lowest unoccupied molecular orbital (ELUMO), and the excited state (EES) were computed by PM3 Hamiltonian.The energies of frontier orbitals, EHOMO and ELUMO, which directed the nucleophilic and electrophilic reactivity of a compound respectively, were calculated using the PM3 Hamiltonian contained in the quantum chemical computation software HYPER (version 5.0).The method of PM3 was selected because it was a recently developed semi-empirical molecular orbital algorithm and the computational time was much shorter than needed by the ab initio methods. All statistical analyses were carried out by ORIGIN software (version 6.0). The regression analysis was used to establish the model. Model quality was characterized by the number of observations (n), the correlation coefficient (R), the standard deviation (SD), the Fisher criterion (F), and the significance level (P). The percentage degradation of test chemical was estimated to be 95% by QSBR models, test chemical can be considered to be readily biodegradable in nature.

 

By considering results of all the studies mentioned above for target chemical and its structurally similar areda across chemical it can be concluded that target 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 ) is readily biodegradable.

Bioaccumulation:

Bioaccumulation: aquatic/sediments:

Predicted data study for target 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) and experimental study for its structurally similar read across chemical have been reviewed for bioaccumulation endpoint and their results are summarized below.

 

The first study was predicted data study in this study the BCFBAF model (v3.01) of Estimation Programs Interface (EPI Suite, 2018) was used to predict the bioconcentration factor (BCF) of test 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 -87 -6). The bioconcentration factor (BCF) of test chemical was estimated to be 3.162 L/kg whole body w.w (at 25 deg C) which does not exceed the bioconcentration threshold of 2000, indicating that 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) is not expected to bioaccumulate in the food chain.

 

To support the above predicted data study experimental study was reviewed from authoritative database (J check) in this study the Bioaccumulation experiment was conducted for 6 weeks for determination the bioconcentration factor (BCF) of test chemical on test organism Cyprinus carpio. 

The vehicle used in the study was HCO-40, Crystal sugar,

Concentration of vehicle: 1st Concentration area: HCO-40 14 ppm(w/v), Crystal sugar 14 ppm(w/v), 2nd Concentration area: HCO-40 1.4 ppm(w/v) Crystal sugar 1.4 ppm(w/v)

Recovery ratio : Test water : 1st concentration area : 96.1 %, 2nd concentration area : 95.4 %, Fish : 79.8 %, - Limit of detection : Fish : 0.25 ppm

 

The Nominal concentrations used in the study was 1st Concentration area: 0.7 mg/L(w/v), 2nd Concentration area: 0.07 mg/L (w/v)and Range finding study was carried out on Rice fish (Oryzias latipes) TLm(48h>= 420 ppm(w/v).Thus according to static Fish test the bioconcentration factor (BCF) for test chemical was determined according static fish test. The BCF value was observed to be 0.9 – 1.8 L/kg at dose concentration 0.7 mg/L and 8.5 - 15 L/kg at dose concentration 0.07 mg/L on test organism Cyprinus carpio during 6 weeks period. Therefore it is concluded that test chemical is non bioaccumulative.

 

 

Another experimental study was also reviewed from authoritative database (J check) in this study the Bioaccumulation experiment was conducted on test organism Cyprinus carpio for 6 weeks for evaluating the bioconcentration factor (BCF value) of chemical . The study was performed according to OECD Guideline 305 (Bioconcentration: Flow-through Fish Test) and other guideline "Bioaccumulation test of a chemical substance in fish or shellfish" provided in "the Notice on the Test Method Concerning New Chemical Substances", respectively at a temperature of 25°C. Cyprinus carpio was used as a test organism for the study. Test chemical nominal conc. used for the study was 0.3mg/land 0.03 mg/l, respectively. Test chemical solution was prepared in HCO-40 and Crystal sugar. Analytical method involve the recovery ratio: Fish : 79.6 %, - Limit of quantitation : Test water : 1st concentration area : 0.017 microg/mL, 2nd concentration area : 0.00 microg/mL, Fish : 0.18 microg/g. Range finding study involve theLC50(48h) >= 50.0 mg/L on Rice fish (Oryzias latipes).The bioconcentration factor (BCF value) of substance on Cyprinus carpio was determined to be in the range of ≤ 0.7-1.8 L/Kg at a conc. of 0.3 mg/l and ≤ 6.9 L/Kg at a conc. of 0.03 mg/l, respectively, which does not exceed the bioconcentration threshold of 2000, indicating that the chemical is not expected to bioaccumulate in the food chain.

 

 By considering all the studies mentioned above it can be conclude that test 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) is non bioaccumulative in nature.

Transport and distribution:

Adsorption/desorption:

Predicted data study for target 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) and experimental study for its structurally similar read across chemical have been reviewed for adsorption endpoint and their results are summarized below.

 

The first study was predicted data study in this the KOCWIN model (v2.00) of Estimation Programs Interface (EPI Suite, 2018) was used to predict the soil adsorption coefficient i.e Koc value of test 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). The soil adsorption coefficient i.e Koc value of test 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) was estimated to be 42200 L/kg (log Koc=4.623)  by means of MCI method (at 25 deg C). This Koc value indicates that the test substance has a very strong sorption to soil and sediment and therefore has negligible migration potential to ground water.

 

 

Next study was experimental study reviewed from study report in this study the adsorption coefficient Koc in soil and in sewage sludge was determined by the Reverse Phase High Performance Liquid Chromatographic method. The reference substances were chosen according to estimated Koc range of the test substance and generalized calibration graph was prepared. The reference substances were Phenol, Aniline, Nitrobenzene, naphthalene, Phenanthrene and DDT were chosen having Koc value ranging from 1.32 to 5.63. The Log Koc value of test chemical was determined to be 3.679 dimensionless at 25°C. Based on the value of log Koc it is concluded that this test chemical has strong sorption to soil and sediments and therefore has slow migration potential to ground water.

 

Another experimental study was reviewed from Screening Assessment for the Challenge; September 2011 in this study the Log Koc values for test substance are based on calculations by Baughman and Perenich (1988) using a range of measured solubility for commercial dyes and an assumed melting point of 200 deg.C. During experiment the Log Koc (Organic carbon water partition coefficient) (dimensionless) was reported to be 3.4 to 4.2.

Based on the result it is concluded that the test chemical has low water solubility and a relatively high Koc it is not likely to leach from sediments and soils means test chemical is immobile in soil and sediment.

 

 By considering results of all the studies mentioned above it can be concluded that test 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) can be expected to have strong sorption to soil and sediments.