Dihydrogen [2,4-dihydro-4-[(2-hydroxy-5-nitrophenyl)azo]-5-methyl-2-phenyl-3H-pyrazol-3-onato(2-)][3-hydroxy-4-[(2-hydroxy-1-naphthyl)azo]-7-nitronaphthalene-1-sulphonato(3-)]chromate(2-)

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

Gene mutation in vitro:

Based on the prediction done using the OECD QSAR toolbox version 3.4 with log kow as the primary descriptor and considering the five closest read across substances, gene mutation was predicted for Dihydrogen [2,4-dihydro-4-[(2-hydroxy-5-nitrophenyl)azo]-5-methyl-2-phenyl-3H-pyrazol-3-onato(2-)] [3-hydroxy-4-[(2-hydroxy-1-naphthyl)azo] -7-nitronaphthalene-1-sulphonato(3-)]chromate(2-). The study assumed the use of Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 with S9 metabolic activation system. Dihydrogen [2,4-dihydro-4-[(2-hydroxy-5-nitrophenyl)azo] -5-methyl-2-phenyl-3H- pyrazol-3-onato(2-)][3-hydroxy-4-[(2-hydroxy-1-naphthyl)azo] -7-nitronaphthalene-1-sulphonato(3-)]chromate(2-) was predicted to not induce gene mutation in Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 in the presence of S9 metabolic activation system and hence, according to the prediction made, it is not likely to classify as a gene mutant in vitro.

 

Based on the predicted result it can be concluded that the substance is considered to not toxic as per the criteria mentioned in CLP regulation.

Link to relevant study records

Reference

Endpoint:

in vitro gene mutation study in bacteria

Remarks:

Type of genotoxicity: gene mutation

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with limited documentation / justification

Justification for type of information:

Data is from OECD QSAR Toolbox version 3.4 and the supporting QMRF report has been attached

Qualifier:

according to guideline

Guideline:

other: Refer below principle

Principles of method if other than guideline:

Prediction is done using OECD QSAR Toolbox version 3.4, 2018

GLP compliance:

not specified

Type of assay:

bacterial reverse mutation assay

Specific details on test material used for the study:

- Name of the test chemical: Dihydrogen [2,4-dihydro-4-[(2-hydroxy-5-nitrophenyl)azo]-5-methyl-2-phenyl-3H-pyrazol-3-onato(2-)][3-hydroxy-4-[(2-hydroxy-1-naphthyl)azo]-7-nitronaphthalene-1-sulphonato(3-)]chromate(2-)
- IUPAC name: Dihydrogen [2,4-dihydro-4-[(2-hydroxy-5-nitrophenyl)azo]-5-methyl-2-phenyl-3H-pyrazol-3-onato(2-)][3-hydroxy-4-[(2-hydroxy-1-naphthyl)azo]-7-nitronaphthalene-1-sulphonato(3-)]chromate(2-)
- Molecular formula: C36H21CrN8O11S.2H
- Molecular weight: 827.6847 g/mol
- Substance type: Organic

Target gene:

Histidine

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA 102

Details on mammalian cell type (if applicable):

Not applicable

Additional strain / cell type characteristics:

not specified

Cytokinesis block (if used):

No data

Metabolic activation:

with

Metabolic activation system:

S9 metabolic activation system

Test concentrations with justification for top dose:

No data

Vehicle / solvent:

No data

Untreated negative controls:

not specified

Negative solvent / vehicle controls:

not specified

True negative controls:

not specified

Positive controls:

not specified

Positive control substance:

not specified

Details on test system and experimental conditions:

No data

Rationale for test conditions:

No data

Evaluation criteria:

Prediction is done considering a dose dependent increase in the number of revertants/plate

Statistics:

No data

Species / strain:

S. typhimurium, other: TA 1535, TA 1537, TA 98 and TA 100

Metabolic activation:

not specified

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

not specified

Untreated negative controls validity:

not specified

Positive controls validity:

not specified

Additional information on results:

No data

Remarks on result:

no mutagenic potential (based on QSAR/QSPR prediction)

The prediction was based on dataset comprised from the following descriptors: "Gene mutation"
Estimation method: Takes highest mode value from the 8 nearest neighbours
Domain  logical expression:Result: In Domain

(((((((("a" or "b" or "c" or "d" )  and "e" )  and ("f" and ( not "g") )  )  and ("h" and ( not "i") )  )  and ("j" and ( not "k") )  )  and ("l" and ( not "m") )  )  and ("n" and ( not "o") )  )  and ("p" and "q" )  )

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as Naphthalene sulfonic acids, condensates by OECD HPV Chemical Categories

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as AN2 OR AN2 >> Michael addition to activated double bonds in heterocyclic ring systems OR AN2 >> Michael addition to activated double bonds in heterocyclic ring systems >> Pyrazolone and Pyrazolidine Derivatives OR AN2 >> Schiff base formation with carbonyl compounds (AN2) OR AN2 >> Schiff base formation with carbonyl compounds (AN2) >> Pyrazolone and Pyrazolidine Derivatives OR Schiff base formation OR Schiff base formation >> Schiff base on pyrazolones and pyrazolidinones OR Schiff base formation >> Schiff base on pyrazolones and pyrazolidinones >> Pyrazolones and Pyrazolidinones by Protein binding by OASIS v1.4 ONLY

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as SN1 OR SN1 >> Nitrenium Ion formation OR SN1 >> Nitrenium Ion formation >> Aromatic azo OR SN1 >> Nitrenium Ion formation >> Aromatic nitro OR SN1 >> Nitrenium Ion formation >> Unsaturated heterocyclic azo by DNA binding by OECD ONLY

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as Non-covalent interaction OR Non-covalent interaction >> DNA intercalation OR Non-covalent interaction >> DNA intercalation >> Fused-Ring Nitroaromatics OR Radical OR Radical >> Radical mechanism via ROS formation (indirect) OR Radical >> Radical mechanism via ROS formation (indirect) >> Fused-Ring Nitroaromatics OR SN1 OR SN1 >> Nucleophilic attack after reduction and nitrenium ion formation OR SN1 >> Nucleophilic attack after reduction and nitrenium ion formation >> Fused-Ring Nitroaromatics by DNA binding by OASIS v.1.4 ONLY

Domain logical expression index: "e"

Referential boundary: The target chemical should be classified as SN1 AND SN1 >> Nitrenium Ion formation AND SN1 >> Nitrenium Ion formation >> Aromatic azo AND SN1 >> Nitrenium Ion formation >> Aromatic nitro AND SN1 >> Nitrenium Ion formation >> Unsaturated heterocyclic azo by DNA binding by OECD ONLY

Domain logical expression index: "f"

Referential boundary: The target chemical should be classified as Non binder, MW>500 by Estrogen Receptor Binding

Domain logical expression index: "g"

Referential boundary: The target chemical should be classified as Moderate binder, NH2 group OR Moderate binder, OH grooup OR Non binder, impaired OH or NH2 group OR Non binder, without OH or NH2 group OR Strong binder, NH2 group OR Strong binder, OH group OR Very strong binder, OH group OR Weak binder, NH2 group OR Weak binder, OH group by Estrogen Receptor Binding

Domain logical expression index: "h"

Referential boundary: The target chemical should be classified as H-acceptor-path3-H-acceptor AND Hydrazine AND Nitro-aromatic by in vivo mutagenicity (Micronucleus) alerts by ISS

Domain logical expression index: "i"

Referential boundary: The target chemical should be classified as alpha,beta-unsaturated carbonyls OR Aromatic diazo by in vivo mutagenicity (Micronucleus) alerts by ISS

Domain logical expression index: "j"

Referential boundary: The target chemical should be classified as Non-Metals AND Transition Metals by Groups of elements

Domain logical expression index: "k"

Referential boundary: The target chemical should be classified as Metals by Groups of elements

Domain logical expression index: "l"

Referential boundary: The target chemical should be classified as Non-Metals AND Transition Metals by Groups of elements

Domain logical expression index: "m"

Referential boundary: The target chemical should be classified as Halogens by Groups of elements

Domain logical expression index: "n"

Referential boundary: The target chemical should be classified as Schiff base formation AND Schiff base formation >> Pyrazolones and Pyrazolidinones derivatives AND Schiff base formation >> Pyrazolones and Pyrazolidinones derivatives >> Pyrazolones and Pyrazolidinones  by Protein binding alerts for skin sensitization by OASIS v1.4

Domain logical expression index: "o"

Referential boundary: The target chemical should be classified as Michael Addition by Protein binding alerts for skin sensitization by OASIS v1.4

Domain logical expression index: "p"

Parametric boundary:The target chemical should have a value of Molecular weight which is >= 675 Da

Domain logical expression index: "q"

Parametric boundary:The target chemical should have a value of Molecular weight which is <= 931 Da

Conclusions:

Dihydrogen [2,4-dihydro-4-[(2-hydroxy-5-nitrophenyl)azo] -5-methyl-2-phenyl-3H- pyrazol-3-onato(2-)][3-hydroxy-4-[(2-hydroxy-1-naphthyl)azo] -7-nitronaphthalene-1-sulphonato(3-)]chromate(2-) was predicted to not induce gene mutation in Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 in the presence of S9 metabolic activation system and hence, according to the prediction made, it is not likely to classify as a gene mutant in vitro.

Executive summary:

Based on the prediction done using the OECD QSAR toolbox version 3.4 with log kow as the primary descriptor and considering the five closest read across substances, gene mutation was predicted for Dihydrogen [2,4-dihydro-4-[(2-hydroxy-5-nitrophenyl)azo]-5-methyl-2-phenyl-3H-pyrazol-3-onato(2-)] [3-hydroxy-4-[(2-hydroxy-1-naphthyl)azo] -7-nitronaphthalene-1-sulphonato(3-)]chromate(2-). The study assumed the use of Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 with S9 metabolic activation system. Dihydrogen [2,4-dihydro-4-[(2-hydroxy-5-nitrophenyl)azo] -5-methyl-2-phenyl-3H- pyrazol-3-onato(2-)][3-hydroxy-4-[(2-hydroxy-1-naphthyl)azo] -7-nitronaphthalene-1-sulphonato(3-)]chromate(2-) was predicted to not induce gene mutation in Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 in the presence of S9 metabolic activation system and hence, according to the prediction made, it is not likely to classify as a gene mutant in vitro.

 

Based on the predicted result it can be concluded that the substance is considered to not toxic as per the criteria mentioned in CLP regulation.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Genetic toxicity in vivo

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Gene mutation in vitro:

Prediction model based estimation for the target chemical and the data from read across chemicals have been reviewed to determine the mutagenic nature of Dihydrogen [2,4-dihydro-4-[(2-hydroxy-5-nitrophenyl)azo]-5-methyl-2-phenyl-3H-pyrazol-3-onato(2-)] [3-hydroxy-4-[(2-hydroxy-1-naphthyl)azo] -7-nitronaphthalene-1-sulphonato(3-)]chromate(2-). The studies are as mentioned below:

Based on the prediction done using the OECD QSAR toolbox version 3.4 with log kow as the primary descriptor and considering the five closest read across substances, gene mutation was predicted for Dihydrogen [2,4-dihydro-4-[(2-hydroxy-5-nitrophenyl)azo]-5-methyl-2-phenyl-3H-pyrazol-3-onato(2-)] [3-hydroxy-4-[(2-hydroxy-1-naphthyl)azo] -7-nitronaphthalene-1-sulphonato(3-)]chromate(2-). The study assumed the use of Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 with and without S9 metabolic activation system. Dihydrogen [2,4-dihydro-4-[(2-hydroxy-5-nitrophenyl)azo] -5-methyl-2-phenyl-3H- pyrazol-3-onato(2-)][3-hydroxy-4-[(2-hydroxy-1-naphthyl)azo] -7-nitronaphthalene-1-sulphonato(3-)]chromate(2-) was predicted to not induce gene mutation in Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 in the presence and absence of S9 metabolic activation system and hence, according to the prediction made, it is not likely to classify as a gene mutant in vitro.

 

The experimental data for tha read across chemicals is as mentioned below:

Gene mutation toxicity study was performed by Matsushima et al (Mutation research, 1978) to determine the mutagenic nature of 50 -60% structurally similar read across chemical Eriochrome Black T (RA CAS no 1787 -61 -7; IUPAC name: (4Z)-4-[(1-hydroxynaphthalen-2-yl) hydrazinylidene] -7-nitro-3- oxonaphthalene-1-sulfonic acid). The mutagenicities of this benzidine diazo-dye was not detected by the Salmonella standard plate method with a metabolic activation system (S-9 Mix) or even by the more sensitive modification (preincubation method) in which tester strain was incubated with the test chemical and S-9 Mix at 30°C for 30 min before plating on minimal glucose agar plates. Addition of riboflavin to the S-9 Mix (1µmole/ml of S-9 Mix) was necessary for demonstration of the mutagenicities of azo- and diazo-compounds by the preincubation method. Riboflavin enhanced the azo-reductase activity in S-9 mix. Eriochrome Black T did not induce mutation in Salmonellatyphimurium strains TA100, TA98, in the presence of S9 metabolic activation system. It however induced gene mutation in in strain TA98 in the absence of S9 metabolic activation system.

This is further supported by data from another 50 -60% strcuturally similar read across chemical. Gene mutation study was conducted by Milvy et al ( Journal of Toxicology and Environmental Health, 1978) to evaluate the mutagenic nature of read across chemical Lithol red (RA CAS no 1284 -18 -6). The study was performed using the preincubation protocol using Salmonella typhimurium TA98, TA1538 and TA1535 both in the presence and absence of S9 metabolic activation system.10 µg of the dye partially or completely dissolved in 0.01 ml of dimethyl sulfoxide (DMSO) was added to 0.9 ml of the reagents in the liquid phase and incubated 30 min at 37°C with shaking before plating 0.1 ml onto minimal plates. Lithol red did not induce mutation in the Salmonella typhimurium TA98, TA1538 and TA1535 in the presence and absence of S9 metabolic activation system and hence is negative for gene mutation in vitro.

Based on the available data for the target chemical and its read across chemical, Dihydrogen (2,4-dihydro-4-((2-hydroxy-5-nitrophenyl)azo)-5-methyl-2-phenyl-3H- pyrazol - 3-onato (2-))(3-hydroxy-4-((2-hydroxy-1-naphthyl)azo)- 7-nitronaphthalene -1- sulphonato(3-)) chromate(2-) is not likely to classify as a gene mutant in vitro.

Justification for classification or non-classification

Based on the available data for the target chemical and its read across read across chemical, Dihydrogen (2,4-dihydro-4-((2-hydroxy-5-nitrophenyl)azo)-5-methyl-2-phenyl-3H- pyrazol - 3-onato (2-))(3-hydroxy-4-((2-hydroxy-1-naphthyl)azo)-7-nitronaphthalene-1- sulphonato(3-))chromate(2-) (CAS no 52953 -39 -6) is not likely to classify as a gene mutant in vitro.