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Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Stability:

Hydrolysis:

According To annex VIII column 2 the study does not need to be conducted because the substance is highly insoluble in water.

Biodegradation in water :

Estimation Programs Interface Suite (EPI suite, 2017) was run to predict the biodegradation potential of the test compound N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amine (CAS no. 93964 -07 -9) 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 Biowin 1-7, respectively) of the BIOWIN v4.10 software. The results indicate that chemical  N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amine is expected to be not readily biodegradable.

Bioaccumulation:

Using Bio-concentration Factor (v12.1.0.50374) module Bio-concentration Factor at range pH 1-14  of the chemicalN-(2-ethylhexyl)-1-[[2-methyl-4-[ (4-methylphenyl) azo]phenyl]azo]naphthalen-2-amine(CAS no.93964 -07 -9) estimated to be> 1000000.0dimensionless. This value indicates that the chemicalN-(2-ethylhexyl)-1-[[2-methyl-4-[ (4-methylphenyl) azo]phenyl]azo]naphthalen-2-amineis very bioaccumulative in aquatic organisms as this value exceeded 2000 criteria.

Adsorption:

The Soil Adsorption Coefficient i.e. Koc value of test chemical N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amine (CAS No. 93964-07-9) was estimated using EPI suite KOCWIN Program (v2.00) as 3.239e+008 L/kg (log Koc= 8.510) by means of MCI method at 25 deg. C.  This log Koc value indicates that test chemical N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amine has Very strong sorption to soil and sediment, negligible migration potential to groundwater.

Additional information

Stability:

Hydrolysis:

According To annex VIII column 2 the study does not need to be conducted because the substance is highly insoluble in water.

Biodegradation:

Biodegradation in water :

Predicted data study for the target compound N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amine (CAS No. 93964-07-9) and supporting weight of evidence studies for its read across substance were reviewed for the biodegradation end point which are summarized as below:

In a prediction using the Estimation Programs Interface Suite (EPI suite, 2017),N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo] naphthalen-2-amine (CAS no. 93964 -07 -9) the biodegradation potential of the test compound in the presence of mixed populations of environmental microorganisms was estimated.

Estimation Programs Interface Suite (EPI suite, 2017) was run to predict the biodegradation potential of the test compound N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amine (CAS no. 93964 -07 -9) 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 Biowin 1-7, respectively) of the BIOWIN v4.10 software. The results indicate that chemical  N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo] naphthalen-2-amine is expected to be not readily biodegradable.

 

The above predicted data was supported by experimental study summarized in Japan Chemical Collaborative Knowledge database (J check, 2017 ) the test chemical Barium bis[2-chloro-5-[(2-hydroxy-1-naphthyl)azo]toluene-4-sulphonate] was subjected to biodegradation test by taking sludge as inoculums at 30 mg/L concentration. Biodegradation was analysed by using BOD parameter. The initial concentration of test chemical was 100 mg/L. After 2 weeks (14 days) test chemical Barium bis[2-chloro-5-[(2-hydroxy-1-naphthyl)azo]toluene-4-sulphonate] showed 0 % biodegradability by BOD parameterand by taking activated sludge as inoculumin 14 daysso it is concluded that test chemical Barium bis[2-chloro-5-[(2-hydroxy-1-naphthyl) azo]toluene-4-sulphonate] is not readily biodegradable.

Further to support predicted data study for target chemical another experimental study was reviewed from peer reviewed journal, in this study an experiment was conducted to determine biodegradability of test chemical Sodium 3-hydroxy-4-[(2-hydroxynaphthyl)azo]-7-nitronaphthalene-1-sulphonate by analyzing its ThOD, BOD, COD, TOC and BOD5/TOC ratio. The COD measurement was performed by the potassium dichromate reflux method based on Japanese Industrial Standards.

In the BOD measurement, a sample solution was taken into a container. Then JIS-BOD testing solutions, i.e. 3 ml of A solution and 1 ml of B, C, D solutions were added to the sample solution, respectively. Then 5 ml of the supernatant of the municipal sewage activated sludge was added to the Sample solution and diluted to 300 ml with water. Immediately, the BOD-time curve was recorded at 20oC using an Ohkura OM-200I type coulometer. The TOC measurement was carried out by a Yanagimoto TOC-ILW. The ThOD, COD, BOD, TOC and BOD5/TOC ratio determined be 1.24, 0.83, 0.143, 0.33, and 0.43 respectively. on the basis of BOD5/TOC ratio value it is concluded that test chemical Sodium3-hydroxy-4-[(2-hydroxynaphthyl)azo]-7-nitronaphthalene- 1-sulphonate A shows high resistance to aerobic degradation it means it is not readily biodegradable in aerobic condition.

On the basis of above results for target chemical N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amine (CAS No. 93964-07-9) (from EPI suite, 2017) and for its read across substance, it can be concluded that the test substance N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl) azo]phenyl] azo]naphthalen -2-amine can be expected to be not readily biodegradable in nature

Bioaccumulation :

Bioaccumulation : aquatic/sediment:

Various predicted data for the target compound N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amine (CAS No. 93964-07-9) and supporting weight of evidence studies for its read across substance were reviewed for the bioaccumulation end point and their results are summarized as below:

 

Bioaccumulation potential of the test material was estimated using ACD (Advanced Chemistry Development)/I-Lab; Algorithm Version: v5.0.0.184

Using Bio-concentration Factor (v12.1.0.50374) module Bio-concentration Factor at range pH 1-14  of the chemical N-(2-ethylhexyl)-1-[[2-methyl-4-[ (4-methylphenyl) azo]phenyl]azo]naphthalen-2-amine (CAS no.93964 -07 -9) estimated to be > 1000000.0 dimensionless. This value indicates that the chemical N-(2-ethylhexyl)-1-[[2-methyl-4-[ (4-methylphenyl) azo]phenyl]azo]naphthalen-2-amine is very bioaccumulative in aquatic organisms as this value exceeded 2000 criteria.

 

The above prediction was further supported by another predicted data estimated by SciFinder, American Chemical Society (ACS); 2017

The Bioconcentration factor (BCF) for test chemical N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amine (CAS No: 93964-07-9) was predicted in aquatic organisms by Scifinder database at pH 1-10 and temperature 25 °C .The Bioconcentration factor (BCF) of test substance  N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amine at pH 1-10 and temperature 25 °C was estimated to be 1.00E6 dimensionless.  This BCF value at pH 1-10 and temperature 25 °C suggests that the test chemical N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amine is very bioaccumulative in aquatic organisms.

 

Another predicted data was estimated using ChemSpider- Free chemical Database, Royal Society of Chemistry, 2017) was used for predicting the bioconcentration factor (BCF) of test chemical N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amine.

The Bioconcentration factor (BCF) for test chemical N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amine (CAS No: 93964-07-8) was predicted in aquatic organisms by Chemspider- ACD/PhysChem Suite at pH 5.5 and pH 7.4.The Bioconcentration factor (BCF) of test substance N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amine at pH 5.5 and pH 7.4 was estimated to be 1000000.00 dimensionless. This BCF value suggests that the test chemical N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amine is very bioaccumulative in aquatic organisms.

 

The above prediction was further supported by experimental data summarized in HSDB (Hazardous Substances Data Bank); US national Library of Medicine reviewed by SRC, 2017 in this study the BCF of test chemical in aquatic organisms was reported as 290000 using a measured log Kow of 7.5 and a recommended regression-derived equation. This BCF value indicates that bioconcentration in aquatic organisms will be an important fate process.

On the basis of above results for target chemical N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amine(from ACD labs, ChemSpider, SciFinder database and CompTox Chemistry Dashboard,  2017) and for its read across substance (from authoritative database HSDB), it can be concluded that the BCF value of test substance N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amine ranges from 1000000.00 - 290000 which exceeds the bioconcentration threshold of 2000, indicating that the chemical N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amine is expected to be very bioaccumulate in the food chain.

Transport and Distribution: 

Adsorption:

Various predicted data for the target compound N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amine (CAS No. 93964-07-9) and supporting weight of evidence studies for its read across substance were reviewed for the adsorption end point which are summarized as below:

 

The Soil Adsorption Coefficient i.e. Koc value of test chemical N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amine (CAS No. 93964-07-9) was estimated using EPI suite KOCWIN Program (v2.00) as 3.239e+008 L/kg (log Koc= 8.510) by means of MCI method at 25 deg. C.  This log Koc value indicates that test chemical N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amine has Very strong sorption to soil and sediment, negligible migration potential to groundwater.

The above prediction was further supported by another estimated data predicted by ACD (Advanced Chemistry Development)/I-Lab predictive module

The Soil Adsorption Coefficient i.e Koc value of test substance N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amine was estimated using Adsorption Coefficient module (v12.1.0.50374) program as Koc 953210 dimensionless (log Koc= 7.0). This log Koc value indicates that test material N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amine has very strong sorption to soil and sediment, negligible migration potential to groundwater.

Additional soil adsorption coefficient i.e Koc value of test chemicalN-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-aminewas estimated using the SciFinder database (American Chemical Society (ACS), 2017).Using Sci Finder database the soil adsorption co-efficient i.e., Koc value of test chemical N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amine was estimated to be 1.00E7 dimensionless ( log Koc = 5.0) at pH 1-10 at temperature 25 deg.c. this value suggests that this tes chemical has very strong sorption to soil and sediment, negligible migration potential to groundwater.

In an another prediction done by using ChemSpider Database (2017),the Soil Adsorption Coefficient i.e Koc value of test substanceN-(2-ethylhexyl)-1- [[2-methyl-4-[(4-methylphenyl) azo]phenyl] azo]naphthalene -2-amine was estimated.

Using Chemspider-ACD/Phy chem suite the soil adsorption co-efficient i.e., Koc value of test substance N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amine was estimated to be 3401 dimensionless (log Koc= 6.5) at pH 5.5 and 7.4 and temperature 25 deg.C This Koc value at different pH indicates that the chemical N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amine has very strong sorption to soil and sediment, negligible migration potential to groundwater.

On the basis of above overall results for target chemical N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amine(from EPI suite, ACD labs,ChemSpider, SciFinder database,2017) it can be concluded that the log Koc value of test substance N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-aminewasin the range of 5-8 dimentionlessindicating that the test chemical N-(2-ethylhexyl)-1-[[2-methyl-4-[(4-methylphenyl)azo]phenyl]azo]naphthalen-2-amine very strong sorption to soil and sediment, negligible migration potential to groundwater.