1,4-bis(p-tolylamino)anthraquinone

Endpoint summary

Description of key information

Hydrolysis

In accordance with column 2 of Annex VIII of the REACH regulation, testing for this endpoint is technically not feasible and does not need to be conducted since the test chemical is insoluble in water.

Biodegradation in water

Biodegradation study was conducted for 28 days for evaluating the percentage biodegradability of test chemical (Experimental study report, 1992).The study was performed in accordance with OECD Guideline 301 C (Ready Biodegradability: Modified MITI Test (I))under aerobic conditions at a temperature of 24°C. Activated sludge, domestic (adaptation not specified) obtained from a domestic waste water sewage plant was used as a test inoculum for the study. Initial test substance conc. used in the study was 30 mg/l. Flasks were used as a test vessel for the study. An amount of sludge from a domestic waste water sewage plant corresponding to 7.5 mg dry material for positive control ANILINE and 25 mg dry material for the test article were added to 250 ml of the final test medium. The test flasks was incubated on a SAPROMAT D12 (Voith GmbH) supplied with an evaluation program. The biodegradation of the test article was followed by exposing it to microorganisms from the secondary effluent of a domestic waste water sewage plant and determined by means of the biochemical oxygen demand (BOD) for 28 days. At the end of the incubation period, samples of atleast 10 ml from all flasks were centrifuged and thereafter directly analysed. TOC analyses were performed with the various filtrates, using a Shimadzu TOC Analyser (Shimadzu TOC 500). Aniline (positive control) was used as a reference substance for the study. Untreated inoculum was used as an inoculum blank. It degraded by 67.8% and 71.5% after 7 and 14 days respectively. A slight degradation was observed in the flask without inoculum, allowing the assumption that the test article was not only degraded by microorganisms. The percentage degradation of test chemical was determined to be 29.9% by BOD parameter in 28 days. Thus, based on percentage degradation,test chemical is considered to be inherently biodegradable in nature.

Bioaccumulation: aquatic / sediment

The bioaccumulation study in fishwas conducted for estimating the BCF (bioaccumulation factor) value of test chemical (authoritative database, 2017). The bioaccumulation factor (BCF) value was calculated using a log Kow of 8.69 and a regression-derived equation. The estimated BCF (bioaccumulation factor) value of test chemical was determined to be 500 dimensionless, which does not exceed the bioconcentration threshold of 2000, indicating that the test chemical is considered to be non-accumulative in aquatic organisms.

Adsorption / desorption

The adsorption coefficient Koc in soil and in sewage sludge of test chemical was determined by the Reverse Phase High Performance Liquid Chromatographic method according to OECD Guideline No. 121 for testing of Chemicals (Experimental study report, 2018). The solutions of the test substance and reference substances were prepared in appropriate solvents. A test item solution was prepared by accurately weighing 4 mg of test item and diluted with Acetonitrile up to 10 ml. Thus, the test solution concentration was 400 mg/l. The pH of test substance was 6.2. Each of the reference substance and test substance were analysed by HPLC at 210 nm. After equilibration of the HPLC system, Urea was injected first, the reference substances were injected in duplicate, followed by the test chemical solution in duplicate. Reference substances were injected again after test sample, no change in retention time of reference substances was observed. Retention time tR were measured, averaged and the decimal logarithms of the capacity factors k were calculated. The graph was plotted between log Koc versus log k(Annex - 2).The linear regression parameter of the relationship log Koc vs log k were also calculated from the data obtained with calibration samples and therewith, log Koc of the test substance was determined from its measured capacity factor. The reference substances were chosen according to estimated Koc range of the test substance and generalized calibration graph was prepared. The reference substances were Acetanilide, 4-chloroaniline, 4-methylaniline(p-Tolouidine), N-methylaniline, p-toluamide, Aniline, 2,5-Dichloroaniline, 4-nitrophenol, 2 - nitrophenol, 2-nitrobenzamide, 3-nitrobenzamide, Nitrobenzene, 4 - Nitrobenzamide, 1 -naphthylamine, 1-naphtol, Direct Red 81, Benzoic acid methylester, Carbendazim, Benzoic acid phenylester, Xylene, Ethylbenzene, Toluene, Naphthalene, 1,2,3-trichlorobenzene, Pentachlorophenol, Phenol, N,N-dimethylbenzamide, 3,5 -dinitrobenzamide, N-methylbenz amide, Benzamide, phenanthrene, DDT having Koc value ranging from 1.25 to 5.63. The Log Koc value of test chemical was determined to be 2.267 ± 0.000 dimensionless at 25°C.This log Koc value indicates that the substance has a low sorption to soil and sediment and therefore have moderate migration potential to ground water.

Additional information

Hydrolysis

In accordance with column 2 of Annex VIII of the REACH regulation, testing for this endpoint is technically not feasible and does not need to be conducted since the test chemical is insoluble in water.

Biodegradation in water

Various experimental key and supporting study of the test chemical were reviewed for the biodegradation end point which are summarized as below:

 

In an experimental key study from study report (1992),biodegradation experiment was conducted for 28 days for evaluating the percentage biodegradability of test chemical. The study was performed in accordance with OECD Guideline 301 C (Ready Biodegradability: Modified MITI Test (I))under aerobic conditions at a temperature of 24°C. Activated sludge, domestic (adaptation not specified) obtained from a domestic waste water sewage plant was used as a test inoculum for the study. Initial test substance conc. used in the study was 30 mg/l. Flasks were used as a test vessel for the study. An amount of sludge from a domestic waste water sewage plant corresponding to 7.5 mg dry material for positive control ANILINE and 25 mg dry material for the test article were added to 250 ml of the final test medium. The test flasks was incubated on a SAPROMAT D12 (Voith GmbH) supplied with an evaluation program. The biodegradation of the test article was followed by exposing it to microorganisms from the secondary effluent of a domestic waste water sewage plant and determined by means of the biochemical oxygen demand (BOD) for 28 days. At the end of the incubation period, samples of atleast 10 ml from all flasks were centrifuged and thereafter directly analysed. TOC analyses were performed with the various filtrates, using a Shimadzu TOC Analyser (Shimadzu TOC 500). Aniline (positive control) was used as a reference substance for the study. Untreated inoculum was used as an inoculum blank. It degraded by 67.8% and 71.5% after 7 and 14 days respectively. A slight degradation was observed in the flask without inoculum, allowing the assumption that the test article was not only degraded by microorganisms. The percentage degradation of test chemical was determined to be 29.9% by BOD parameter in 28 days. Thus, based on percentage degradation, test chemical is considered to be inherently biodegradable in nature.

 

In a supporting study,28-days Closed Bottle test following the OECD guideline 301 D to determine the ready biodegradability of the test chemical (Experimental study report, 2018. The study was performed at a temperature of 20°C. The test system included control, test item and reference item. Polyseed were used as a test inoculum for the study. 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 73.49%. Degradation of Sodium Benzoate exceeds 39.15% on 7 days & 70.48% on 14th day. The activity of the inoculum was thus verified and the test can be considered as valid. The BOD28 value of test chemical was observed to be 1 mgO2/mg. ThOD was calculated as 2.37 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 42.19%. Based on the results, the test item, under the test conditions, was considered to be inherently biodegradable in nature.

 

On the basis of above results, the test chemicalcan be considered to beinherently biodegradable in nature.

Bioaccumulation: aquatic / sediment

Various studies and predicted data of the test chemical were reviewed for the bioaccumulation end point which are summarized as below:

 

In a key study from authoritative databases (2017), the bioaccumulation study in fishwas conducted for estimating the BCF (bioaccumulation factor) value of test chemical. The bioaccumulation factor (BCF) value was calculated using a log Kow of 8.69 and a regression-derived equation. The estimated BCF (bioaccumulation factor) value of test chemical was determined to be 500 dimensionless.

 

In a supporting study, the bioaccumulation study in fish was conducted for estimating the BCF (bioaccumulation factor) value of test chemical (secondary source, 2005). The estimated BCF (bioaccumulation factor) value of test chemical was determined to be 45.70 dimensionless.

 

For the test chemical, bioaccumulation study in fish was conducted for estimating the BCF (bioaccumulation factor) value of test chemical (secondary source, 1987). The bioaccumulation factor (BCF) value was calculated using a log Kow of 6.657 and a regression-derived equation. The estimated BCF (bioaccumulation factor) value of test chemical was determined to be ≥ 1000 dimensionless.

 

In a prediction done using the BCFBAF Program of Estimation Programs Interface was used to predict the bioconcentration factor (BCF) of test chemical. The bioconcentration factor (BCF) of test chemical was estimated to be 516.4 L/kg whole body w.w (at 25 deg C).

 

On the basis of above results for test chemical (from authoritative databases, secondary source and modelling database,2018), it can be concluded that the BCF value of test chemical ranges from 45.70 to ≥ 1000, respectively,which does not exceed the bioconcentration threshold of 2000, indicating that the test chemical is not expected to bioaccumulate in the food chain.

Adsorption / desorption

The adsorption coefficient Koc in soil and in sewage sludge of test chemical was determined by the Reverse Phase High Performance Liquid Chromatographic method according to OECD Guideline No. 121 for testing of Chemicals (Experimental study report, 2018). The solutions of the test substance and reference substances were prepared in appropriate solvents. A test item solution was prepared by accurately weighing 4 mg of test item and diluted with Acetonitrile up to 10 ml. Thus, the test solution concentration was 400 mg/l. The pH of test substance was 6.2. Each of the reference substance and test substance were analysed by HPLC at 210 nm. After equilibration of the HPLC system, Urea was injected first, the reference substances were injected in duplicate, followed by the test chemical solution in duplicate. Reference substances were injected again after test sample, no change in retention time of reference substances was observed. Retention time tR were measured, averaged and the decimal logarithms of the capacity factors k were calculated. The graph was plotted between log Koc versus log k(Annex - 2).The linear regression parameter of the relationship log Koc vs log k were also calculated from the data obtained with calibration samples and therewith, log Koc of the test substance was determined from its measured capacity factor. The reference substances were chosen according to estimated Koc range of the test substance and generalized calibration graph was prepared. The reference substances were Acetanilide, 4-chloroaniline, 4-methylaniline(p-Tolouidine), N-methylaniline, p-toluamide, Aniline, 2,5-Dichloroaniline, 4-nitrophenol, 2 - nitrophenol, 2-nitrobenzamide, 3-nitrobenzamide, Nitrobenzene, 4 - Nitrobenzamide, 1 -naphthylamine, 1-naphtol, Direct Red 81, Benzoic acid methylester, Carbendazim, Benzoic acid phenylester, Xylene, Ethylbenzene, Toluene, Naphthalene, 1,2,3-trichlorobenzene, Pentachlorophenol, Phenol, N,N-dimethylbenzamide, 3,5 -dinitrobenzamide, N-methylbenz amide, Benzamide, phenanthrene, DDT having Koc value ranging from 1.25 to 5.63. The Log Koc value of test chemical was determined to be 2.267 ± 0.000 dimensionless at 25°C.This log Koc value indicates that the substance has a low sorption to soil and sediment and therefore have moderate migration potential to ground water.