3,4-dicyanoaniline

Endpoint summary

Description of key information

Short term toxicity to aquatic invertebrate:

Based on the prediction done by EPI suite, ECOSAR version 1.1, on the basis of similarity of structure to chemicals for which the aquatic toxicity has been previously measured by structure-activity relationships (SARs) program, the LC50 value for short term toxicity to aquatic invertebrates was predicted. On the basis of this programe, the LC50 value for short term toxicity to aquatic invertebrates was predicted to be 836.536 mg/l for 4-aminobenzene-1,2-dicarbonitrile in 48 hrs. Based on this value it can be concluded that the substance 4-aminobenzene-1,2-dicarbonitrile is considered to be not toxic to aquatic environment and cannot be classified as per the criteria mentioned in CLP regulation.

 

Toxicity to aquatic algae:

Based on the prediction done using the EPI Suite ECOSAR version 1.10, the short term toxicity on green algae was predicted for test substance 4-aminobenzene-1,2-dicarbonitrile    (CAS:56765 -79 -8). On the basis of effects observed in a static freshwater system, the effect concentration EC50 value for the substance 4-aminobenzene-1,2-dicarbonitrile is estimated to be 382.320 mg/l for green algae for 96 hrs of duration. Based on this value, it can be concluded that the test chemical 4-aminobenzene-1,2-dicarbonitrile can be considered as non-toxic to green algae at environmentally relevant concentrations and can be considered not-classified as per the CLP classification criteria.

Additional information

Summarized result for the determination of effect of chemical when exposed with the aquatic invertebrates and algae are as follows:

Short term toxicity to aquatic invertebrate:

Following studies include the predicted study for the target chemical and the experimental studies for the structurally similar read across to conclude the toxicity extent 4-aminobenzene-1,2-dicarbonitrile (Cas no: 56765-79-8) towards aquatic invertebrate is summarized as follows:

 

The first study used based on the prediction done by EPI suite, ECOSAR version 1.1, on the basis of similarity of structure to chemicals for which the aquatic toxicity has been previously measured by structure-activity relationships (SARs) program, the LC50 value for short term toxicity to aquatic invertebrates was predicted. On the basis of this programe, the LC50 value for short term toxicity to aquatic invertebrates was predicted to be 836.536 mg/l for 4-aminobenzene-1,2-dicarbonitrile in 48 hrs. Based on this value it can be concluded that the substance 4-aminobenzene-1,2-dicarbonitrile is considered to be not toxic to aquatic environment and cannot be classified as per the criteria mentioned in CLP regulation.

 

First predicted study supported by the another weight of evidence study based on the prediction done using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the six closest read across substances, toxicity on daphnia magna was predicted for 4-aminobenzene-1,2-dicarbonitrile (56765-79-8). Based on the immobility of test organism the EC50 value was estimated to be 154.5653 mg/l when 4-aminobenzene-1,2-dicarbonitrile exposed to daphnia magna for 48 hrs. Based on this value it can be concluded that the substance 4-aminobenzene-1,2-dicarbonitrileis considered to be not toxic to aquatic environment as per the criteria mentioned in CLP regulation.   

 

Similarly in the third weight of evidence study for the read across chemical Benzonitrile (100-47-0) from HSDB, and secondary source U.S. Environment protection agency, determination of short term toxicity of Benzonitrile on the growth of aquatic invertebrates. Test was performed in the static system with the total exposure period of 24 hrs. <=24 h old daphnia magna were used in the study. After the exposure of 24hrs LC50 was determine on the basis of intoxication. Based on the intoxication of daphnia magna due to the exposure of chemical benzonitrile for 24hrs, the LC50 was 200 mg/l. 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.

 

Further study was carried out on the read across chemical 1,2-Dicyanobenzene (91-15-6) which was structurally as well as functionally similar to the target chemical from authoritative database j-check, 2017. Acute Immobilization Test of 1,2-Dicyanobenzene to Daphnia magna was studied by following the OECD Guideline 202 (Daphnia sp., Acute Immobilisation Test and Reproduction Test). Test conducted in the static system for the total exposure period of 48hrs. Sample analyze by the HPLC. Toxicity measured at the nominal concentration control, 25.0, 45.0, 79.0, 140, 250 mg/L. 100 mL per vessel test solution volume was added, on 5 daphnia magna per vessel (20 per concentration) toxicity was checked. Results after 24-hour exposure i.e. Median immobilization concentration (EiC50) was > 250 mg/L. No observed effect concentration (NOECi) observed at 140 mg/L. Lowest concentration of 100 % inhibition at > 250 mg/L. After 48-hour OF exposure No observed effect concentration at 79.0 mg/L and lowest concentration of 100 % inhibition was at the concentration of > 250 mg/L. Based on the immobility of daphnia magna due to the exposure of chemical 1,2-Dicyanobenzene, the EC50 for 48hrs of exposure was 211 mg/l. Based on the EC50, it can be concluded that the chemical 1,2-Dicyanobenzene was nontoxic and cannot be classified as per CLP classification.

 

Thus based on the predicted data for the target chemical and experimental studies for the read across chemical obtain from various sources (J-check, HSDB, U.S. Environment protection agency, 2017) toxicity on aquatic invertebrates was studied due to the exposure of 4-aminobenzene-1,2-dicarbonitrile (Cas no: 56765-79-8), it was concluded that the chemical 4-aminobenzene-1,2-dicarbonitrile was consider as nontoxic and can be consider to be not classified as toxic to aquatic invertebrates as per CLP classification criteria.  

 

Toxicity to aquatic algae:

Based on the various prediction data for the target chemical and experimental data for the read across chemical study have been reviewed to determine the toxic nature of 4-aminobenzene-1,2-dicarbonitrile (Cas no: 56765-79-8) on the growth of aquatic algae. The studies are as mentioned below:

The first predicted study for the target chemical used based on the prediction done using the EPI Suite ECOSAR version 1.10, the short term toxicity on green algae was predicted for test substance 4-aminobenzene-1,2-dicarbonitrile    (CAS:56765 -79 -8). On the basis of effects observed in a static freshwater system, the effect concentration EC50 value for the substance 4-aminobenzene-1,2-dicarbonitrile is estimated to be 382.320 mg/l for green algae for 96 hrs of duration. Based on this value, it can be concluded that the test chemical 4-aminobenzene-1,2-dicarbonitrile can be considered as non-toxic to green algae at environmentally relevant concentrations and can be considered not-classified as per the CLP classification criteria.

 

First predicted study supported by the another weight of evidence study based on the prediction done using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the six closest read across substances, toxicity on Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum) was predicted for 4-aminobenzene-1,2-dicarbonitrile (56765-79-8). Based on the growth rate inhibition of test organism the EC50 value was estimated to be 104.422 mg/l when 4-aminobenzene-1,2-dicarbonitrile exposed to Pseudokirchneriella subcapitata for 72 hrs. Based on this value it can be concluded that the substance 4-aminobenzene-1,2-dicarbonitrile is considered to be not toxic to aquatic algal environment as per the criteria mentioned in CLP regulation.   

 

Further it is supported by another structurally similar read across 3-Aminophenol (CAS: 591-27-5) from the authoritative database also suggests that the toxicity test result shows that the chemical was nontoxic. Short term toxicity to green algae study was carried out for 72 hrs.The study was based on the effects of the test compound 3 -aminophenol (CAS no. 591 -27 -5) on green algae in a static fresh water system. Based on effect on growth rate of the test organism green algae, the 72 hr EC50 and NOEC value was determined to be 160 and 25 mg/l, and on the basis of biomass and area under the growth curve, the 72 hr EC50 and NOEC value was determined to be 62 and 25 mg/l, respectively. Thus, based on the EC50 value (160 mg/l), it can be concluded that the substance 3 -aminophenol can be considered as non-toxic to aquatic organisms and thus can be considered to be not classified as per the CLP classification criteria.

 

Similarly in the fourth weight of evidence study for the read across chemical 1,2-Dicyanobenzene (91-15-6) which was structurally as well as functionally similar to the target chemical from authoritative database j-check, 2017 study has been conducted. Study was conducted to check the nature of chemical when green algae test organisms comes in contact with the chemical 1,2-Dicyanobenzene. Test was performed in the static system for the total exposure of 48 hrs of exposure. Based on the growth rate inhibition of green algae due to the exposure of chemical 1,2-Dicyanobenzene for 72hrs , the EC50 and NOEC was 140 mg/l 32 mg/l. And on the basis of areas under the growth curves the EC50 and NOEC was 68 mg/l and 32 mg/l. Based on the EC50 (140 mg/l), it can be concluded that the chemical 1,2-Dicyanobenzene was nontoxic and can be consider to be not classified as per the CLP classification criteria.

 

Thus based on the predicted data for the target chemical and experimental studies for the read across chemical obtain from various sources (J-check, 2017) toxicity on aquatic algae was studied due to the exposure of 4-aminobenzene-1,2-dicarbonitrile (Cas no: 56765-79-8), and it was concluded that the chemical 4-aminobenzene-1,2-dicarbonitrile was consider as nontoxic and can be consider to be not classified as toxic to algal and cyanobacterial growth as per CLP classification criteria.  

 

Based on the data obtain from various sources for evaluating the toxicity of target chemical 4-aminobenzene-1,2-dicarbonitrile (Cas no: 56765-79-8), on the invertebrates and algal growth, it can be concluded that the substance 4-aminobenzene-1,2-dicarbonitrile is considered to be nontoxic and can be consider to be not classified as toxic to aquatic environment as per CLP classification criteria.