4-[[5-[[4-chloro-6-[(3-sulphophenyl)amino]-1,3,5-triazin-2-yl]amino]-2-sulphophenyl]azo]-4,5-dihydro-5-oxo-1-(4-sulphophenyl)-1H-pyrazole-3-carboxylic acid

Endpoint summary

Description of key information

Acute oral toxicity: Acute oral toxicity dose (LD50) of 4-[(E)-2-(5-{[(2Z,4E)-6-chloro-4-[(3-sulfophenyl)imino]-1,2,3,4-tetrahydro-1,3,5-triazin-2-ylidene]amino}-2-sulfophenyl)

diazen-1-yl]-5-oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid (CAS no: 93858-25-4) was predicted based on OECD QSAR toolbox 2298 mg/kg bw and

different studies available on structurally similar read across substances Trisodium 5-hydroxy-1-(4-sulphophenyl)-4-(4-sulphophenylazo)pyrazole-3-carboxylate (1934-21-0) >6250 mg/kg bw; and 4,4'-bis[4,6-bis(anilino)-1,3,5-triazin-2-yl]aminostilbene-2,2'-disulphonic acid (CAS no: 88-38-0)>10000 mg/kg bw. All these studies concluded that the LD50 value is >2000 mg/kg bw. Thus, comparing this value with the criteria of CLP regulation, 4-[(E)-2-(5-{[(2Z,4E)-6-chloro-4-[(3-sulfophenyl)imino] -1,2,3,4-tetrahydro-1,3,5-triazin-2-ylidene] amino}-2-sulfophenyl)diazen-1-yl]-5-oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid cannot be classified for acute oral toxicity.

Acute Inhalation toxicity: 

4-[(E)-2-(5-{[(2Z,4E)-6-chloro-4-[(3-sulfophenyl)imino]-1,2,3,4-tetrahydro-1,3,5-triazin-2-ylidene]amino}-2-sulfophenyl)diazen-1-yl]-5-oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-

pyrazole-3-carboxylic acid (CAS no: 93858-25-4) has very low vapour pressure (8.83E-39 mmHg), so the potential for the generation of inhalable vapours is very low.

Also the normal conditions of use of this substance will not result in aerosols, particles or droplets of an inhalable size, so exposure to humans via the inhalatory route

will be highly unlikely and therefore this end point was considered for waiver.

 

Acute Dermal toxicity: 

Acute Dermal toxicity dose (LD50) for 4-[(E)-2-(5-{[(2Z,4E)-6-chloro-4-[(3-sulfophenyl)imino]-1,2,3,4-tetrahydro-1,3,5-triazin-2-ylidene]amino}-2-sulfophenyl)diazen-1-yl]- 5-oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid (CAS no: 93858-25-4) was predicted based on OECD QSAR toolbox 9466 mg/kg bw and different studies available for the structurally similar read across substances Aluminium, 6-hydroxy-5-[(4-sulfophenyl)azo]-2-naphthalenesulfonic acid complex (CAS No. 15790-07-5) >2000 mg/kg bw and 4,4'-bis[4,6-bis(anilino)- 1,3,5-triazin-2-yl]aminostilbene-2,2'-disulphonic acid (CAS no: 88-38-0) >3000 mg/kg bw. All these studies concluded that the LD50 value is>2000 mg/kg bw. Thus, comparing this value with the criteria of CLP regulation, 4-[(E)-2-(5-{[(2Z,4E)-6-chloro-4-[(3-sulfophenyl)imino]-1,2,3,4-tetrahydro- 1,3,5-triazin-2-ylidene]amino} -2-sulfophenyl)diazen-1-yl]-5-oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid cannot be classified for acute dermal toxicity.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

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 predicted using OECD QSAR toolbox version 3.3 and the supporting QMRF report has been attached.

Qualifier:

according to guideline

Guideline:

other: estimated data

Principles of method if other than guideline:

Prediction is done using QSAR Toolbox version 3.3

GLP compliance:

not specified

Test type:

other: not specified

Limit test:

no

Specific details on test material used for the study:

Name:4-[(E)-2-(5-{[(2Z,4E)-6-chloro-4-[(3-sulfophenyl)imino]-1,2,3,4-tetrahydro-1,3,5-triazin-2-ylidene]amino}-2-sulfophenyl)diazen-1-yl]-5-oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid
SMILES:OC(=O)C1C(N=Nc2cc(Nc3nc(Nc4cccc(S(O)(=O)=O)c4)nc(Cl)n3)ccc2S(O)(=O)=O)C(=O)N(c2ccc(S(O)(=O)=O)cc2)N=1
InChI:1S/C25H18ClN9O12S3/c26-23-29-24(27-12-2-1-3-16(10-12)49(42,43)44)31-25(30-23)28-13-4-9-18(50(45,46)47)17(11-13)32-33-19-20(22(37)38)34-35(21(19)36)14-5-7-15(8-6-14)48(39,40)41/h1-11,19H,(H,37,38)(H,39,40,41)(H,42,43,44)(H,45,46,47)(H2,27,28,29,30,31)/b33-32+
Mol. formula: C25H18ClN9O12S3
Molecular Weight: 768.1192 g/mole

Species:

rat

Strain:

other: albino rats

Sex:

male/female

Details on test animals or test system and environmental conditions:

not specified

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

not specified

Doses:

2298 mg/kg bw

No. of animals per sex per dose:

3

Control animals:

not specified

Details on study design:

not specified

Statistics:

not specified

Preliminary study:

not specified

Sex:

male/female

Dose descriptor:

LD50

Effect level:

2 298 mg/kg bw

Based on:

test mat.

Remarks on result:

other: 50% mortality was observed

Mortality:

not specified

Clinical signs:

other: not specified

Gross pathology:

not specified

Other findings:

not specified

The prediction was based on dataset comprised from the following descriptors: LD50
Estimation method: Takes average value from the 6 nearest neighbours
Domain  logical expression:Result: In Domain

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

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as Substituted Triazines (Acute toxicity) by US-EPA New Chemical Categories

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as Acid moiety OR Amides OR Hydrazines OR Triazines, Aromatic by Aquatic toxicity classification by ECOSAR ONLY

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as Acylation OR Acylation >> Direct Acylation Involving a Leaving group OR Acylation >> Direct Acylation Involving a Leaving group >> Acetates OR SN2 OR SN2 >> SN2 reaction at sp3 carbon atom OR SN2 >> SN2 reaction at sp3 carbon atom >> Alkyl diazo OR SNAr OR SNAr >> Nucleophilic aromatic substitution OR SNAr >> Nucleophilic aromatic substitution >> Halo-triazines by Protein binding by OECD ONLY

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as Schiff base formation OR Schiff base formation >> Pyrazolones and Pyrazolidinones derivatives OR Schiff base formation >> Pyrazolones and Pyrazolidinones derivatives >> Pyrazolones and Pyrazolidinones  OR SNAr OR SNAr >> Nucleophilic aromatic substitution on activated aryl and heteroaryl compounds OR SNAr >> Nucleophilic aromatic substitution on activated aryl and heteroaryl compounds >> Activated aryl and heteroaryl compounds by Protein binding by OASIS v1.3 ONLY

Domain logical expression index: "e"

Referential boundary: The target chemical should be classified as SN1 OR SN1 >> Nitrenium Ion formation OR 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 No alert found by DNA binding by OASIS v.1.3 ONLY

Domain logical expression index: "g"

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

Domain logical expression index: "h"

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, non cyclic structure OR Non binder, without OH or NH2 group OR Strong binder, OH group OR Very strong binder, OH group OR Weak binder, OH group by Estrogen Receptor Binding

Domain logical expression index: "i"

Referential boundary: The target chemical should be classified as Acylation AND Acylation >> Direct Acylation Involving a Leaving group AND Acylation >> Direct Acylation Involving a Leaving group >> Acetates AND SN2 AND SN2 >> SN2 reaction at sp3 carbon atom AND SN2 >> SN2 reaction at sp3 carbon atom >> Alkyl diazo AND SNAr AND SNAr >> Nucleophilic aromatic substitution AND SNAr >> Nucleophilic aromatic substitution >> Halo-triazines by Protein binding by OECD ONLY

Domain logical expression index: "j"

Referential boundary: The target chemical should be classified as Reactive unspecified by Acute aquatic toxicity MOA by OASIS ONLY

Domain logical expression index: "k"

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

Domain logical expression index: "l"

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

Domain logical expression index: "m"

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

Domain logical expression index: "n"

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

Domain logical expression index: "o"

Referential boundary: The target chemical should be classified as Aromatic amine AND Aromatic heterocyclic halide AND Aryl AND Aryl halide AND Azo AND Carboxylic acid AND Pyrazolone AND Sulfonic acid AND Triazine AND Unsaturated heterocyclic amine AND Unsaturated heterocyclic fragment by Organic Functional groups ONLY

Domain logical expression index: "p"

Referential boundary: The target chemical should be classified as Aromatic amine AND Aromatic heterocyclic halide AND Aryl AND Aryl halide AND Azo AND Carboxylic acid AND Pyrazolone AND Sulfonic acid AND Triazine AND Unsaturated heterocyclic amine AND Unsaturated heterocyclic fragment by Organic Functional groups ONLY

Domain logical expression index: "q"

Referential boundary: The target chemical should be classified as Aromatic amine AND Aromatic heterocyclic halide AND Aryl AND Aryl halide AND Azo AND Carboxylic acid AND Pyrazolone AND Sulfonic acid AND Triazine AND Unsaturated heterocyclic amine AND Unsaturated heterocyclic fragment by Organic Functional groups ONLY

Domain logical expression index: "r"

Parametric boundary:The target chemical should have a value of log Kow which is >= -0.484

Domain logical expression index: "s"

Parametric boundary:The target chemical should have a value of log Kow which is <= 3.79

Interpretation of results:

other: Not classified

Conclusions:

LD50 was estimated to be 2298 mg/kg bw, when 3 male and female albino rats were treated with 4-[(E)-2-(5-{[(2Z,4E)-6-chloro-4-[(3-sulfophenyl)imino]-1,2,3,4-tetrahydro- 1,3,5-triazin-2-ylidene]amino}-2-sulfophenyl)diazen-1-yl]-5-oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid (CAS no: 93858-25-4) via oral gavage route.

Executive summary:

In a prediction done by SSS (2017) using the OECD QSAR toolbox with log kow as the primary descriptor, the acute oral toxicity was estimated for 4-[(E)-2-(5-{[(2Z,4E)-6-chloro-4-[(3-sulfophenyl)imino]-1,2,3,4-tetrahydro-1,3,5-triazin-2-ylidene]amino}-2-sulfophenyl)diazen-1-yl]-5-oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid (CAS no: 93858-25-4). The LD50 was estimated to be 2298 mg/kg bw, when 3 male and female albino rats were treated with 4-[(E)-2-(5-{[(2Z,4E)-6-chloro-4-[(3-sulfophenyl)imino]-1,2,3,4-tetrahydro-1,3,5-triazin-2-ylidene]amino}-2-sulfophenyl)diazen-1-yl]-5-oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid via oral gavage route.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 298 mg/kg bw

Quality of whole database:

Data is Klimisch 2 and from QSAR toolbox 3.3.

Acute toxicity: via inhalation route

Link to relevant study records

Reference

Endpoint:

acute toxicity: inhalation

Data waiving:

other justification

Justification for data waiving:

other:

Endpoint conclusion

Quality of whole database:

Waiver

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

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 predicted using OECD QSAR toolbox version 3.3 and the supporting QMRF report has been attached.

Qualifier:

according to guideline

Guideline:

other: estimated data

Principles of method if other than guideline:

Prediction is done using QSAR Toolbox version 3.3.

GLP compliance:

not specified

Test type:

other: not specified

Limit test:

no

Specific details on test material used for the study:

Name:4-[(E)-2-(5-{[(2Z,4E)-6-chloro-4-[(3-sulfophenyl)imino]-1,2,3,4-tetrahydro-1,3,5-triazin-2-ylidene]amino}-2-sulfophenyl)diazen-1-yl]-5-oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid
SMILES:OC(=O)C1C(N=Nc2cc(Nc3nc(Nc4cccc(S(O)(=O)=O)c4)nc(Cl)n3)ccc2S(O)(=O)=O)C(=O)N(c2ccc(S(O)(=O)=O)cc2)N=1
InChI:1S/C25H18ClN9O12S3/c26-23-29-24(27-12-2-1-3-16(10-12)49(42,43)44)31-25(30-23)28-13-4-9-18(50(45,46)47)17(11-13)32-33-19-20(22(37)38)34-35(21(19)36)14-5-7-15(8-6-14)48(39,40)41/h1-11,19H,(H,37,38)(H,39,40,41)(H,42,43,44)(H,45,46,47)(H2,27,28,29,30,31)/b33-32+
Mol. formula: C25H18ClN9O12S3
Molecular Weight: 768.1192 g/mole

Species:

rabbit

Strain:

New Zealand White

Sex:

male/female

Details on test animals or test system and environmental conditions:

not specified

Type of coverage:

occlusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

not specified

Duration of exposure:

24 hours

Doses:

9466 mg/kg bw

No. of animals per sex per dose:

10

Control animals:

not specified

Details on study design:

not specified

Statistics:

not specified

Preliminary study:

not specified

Sex:

male/female

Dose descriptor:

LD50

Effect level:

9 466 mg/kg bw

Based on:

test mat.

Remarks on result:

other: 50% mortality was observed

Mortality:

not specified

Clinical signs:

other: not specified

Gross pathology:

not specified

Other findings:

not specified

The prediction was based on dataset comprised from the following descriptors: LD50
Estimation method: Takes average value from the 5 nearest neighbours
Domain  logical expression:Result: In Domain

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

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as Substituted Triazines (Acute toxicity) by US-EPA New Chemical Categories

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as Acid moiety OR Amides OR Hydrazines OR Triazines, Aromatic by Aquatic toxicity classification by ECOSAR ONLY

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as Acylation OR Acylation >> Direct Acylation Involving a Leaving group OR Acylation >> Direct Acylation Involving a Leaving group >> Acetates OR SN2 OR SN2 >> SN2 reaction at sp3 carbon atom OR SN2 >> SN2 reaction at sp3 carbon atom >> Alkyl diazo OR SNAr OR SNAr >> Nucleophilic aromatic substitution OR SNAr >> Nucleophilic aromatic substitution >> Halo-triazines by Protein binding by OECD ONLY

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as Schiff base formation OR Schiff base formation >> Pyrazolones and Pyrazolidinones derivatives OR Schiff base formation >> Pyrazolones and Pyrazolidinones derivatives >> Pyrazolones and Pyrazolidinones  OR SNAr OR SNAr >> Nucleophilic aromatic substitution on activated aryl and heteroaryl compounds OR SNAr >> Nucleophilic aromatic substitution on activated aryl and heteroaryl compounds >> Activated aryl and heteroaryl compounds by Protein binding by OASIS v1.3 ONLY

Domain logical expression index: "e"

Referential boundary: The target chemical should be classified as SN1 OR SN1 >> Nitrenium Ion formation OR 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 No alert found by DNA binding by OASIS v.1.3 ONLY

Domain logical expression index: "g"

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

Domain logical expression index: "h"

Referential boundary: The target chemical should be classified as Non binder, non cyclic structure by Estrogen Receptor Binding

Domain logical expression index: "i"

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  AND SNAr AND SNAr >> Nucleophilic aromatic substitution on activated aryl and heteroaryl compounds AND SNAr >> Nucleophilic aromatic substitution on activated aryl and heteroaryl compounds >> Activated aryl and heteroaryl compounds by Protein binding by OASIS v1.3 ONLY

Domain logical expression index: "j"

Referential boundary: The target chemical should be classified as Acylation AND Acylation >> Direct Acylation Involving a Leaving group AND Acylation >> Direct Acylation Involving a Leaving group >> Acetates AND SN2 AND SN2 >> SN2 reaction at sp3 carbon atom AND SN2 >> SN2 reaction at sp3 carbon atom >> Alkyl diazo AND SNAr AND SNAr >> Nucleophilic aromatic substitution AND SNAr >> Nucleophilic aromatic substitution >> Halo-triazines by Protein binding by OECD ONLY

Domain logical expression index: "k"

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

Domain logical expression index: "l"

Referential boundary: The target chemical should be classified as alpha,beta-unsaturated carbonyls OR N-methylol derivatives OR No alert found by in vivo mutagenicity (Micronucleus) alerts by ISS

Domain logical expression index: "m"

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

Domain logical expression index: "n"

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

Domain logical expression index: "o"

Referential boundary: The target chemical should be classified as Aromatic amine AND Aromatic heterocyclic halide AND Aryl AND Aryl halide AND Azo AND Carboxylic acid AND Pyrazolone AND Sulfonic acid AND Triazine AND Unsaturated heterocyclic amine AND Unsaturated heterocyclic fragment by Organic Functional groups ONLY

Domain logical expression index: "p"

Referential boundary: The target chemical should be classified as Aromatic amine AND Aromatic heterocyclic halide AND Aryl AND Aryl halide AND Azo AND Carboxylic acid AND Pyrazolone AND Sulfonic acid AND Triazine AND Unsaturated heterocyclic amine AND Unsaturated heterocyclic fragment by Organic Functional groups ONLY

Domain logical expression index: "q"

Parametric boundary:The target chemical should have a value of log Kow which is >= 0.247

Domain logical expression index: "r"

Parametric boundary:The target chemical should have a value of log Kow which is <= 3.55

Interpretation of results:

other: Not classified

Conclusions:

LD50 was estimated to be 9466 mg/kg bw, when 10 male and female New Zealand White rabbits were treated with 4-[(E)-2-(5-{[(2Z,4E)-6-chloro-4-[(3-sulfophenyl)imino]-1,2,3,4-tetrahydro- 1,3,5-triazin-2-ylidene]amino}-2-sulfophenyl)diazen-1-yl]-5-oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid (CAS no: 93858-25-4) for 24 hours by dermal application occlusively.

Executive summary:

In a prediction done by SSS (2017) using the OECD QSAR toolbox with log kow as the primary descriptor, the acute dermal toxicity was estimated for 4-[(E)-2-(5-{[(2Z,4E)-6-chloro-4-[(3-sulfophenyl)imino]-1,2,3,4-tetrahydro-1,3,5-triazin-2-ylidene]amino}-2-sulfophenyl)diazen-1-yl]-5-oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid (CAS no: 93858-25-4). The LD50 was estimated to be 9466 mg/kg bw, when 10 male and female New Zealand White rabbits were treated with 4-[(E)-2-(5-{[(2Z,4E)-6-chloro-4-[(3-sulfophenyl)imino]-1,2,3,4-tetrahydro-1,3,5-triazin-2-ylidene]amino}-2-sulfophenyl)diazen-1-yl]-5-oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid for 24 hours by dermal application occlusively.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

9 466 mg/kg bw

Quality of whole database:

Data is Klimisch 2 and from QSAR toolbox 3.3.

Additional information

Acute oral toxicity:

In different studies, 4-[(E)-2-(5-{[(2Z,4E)-6-chloro-4-[(3-sulfophenyl)imino]-1,2,3,4-tetrahydro-1,3,5-triazin-2-ylidene]amino}-2-sulfophenyl)diazen-1-yl]-5-oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid (CAS no: 93858-25-4) has been investigated for acute oral toxicity to a greater or lesser extent. Often are the studies based on in-vivo experiments in rodents, i.e. most commonly in rats and mice for 4-[(E)-2-(5-{[(2Z,4E)-6-chloro-4-[(3-sulfophenyl)imino]-1,2,3,4-tetrahydro-1,3,5-triazin-2-ylidene]amino}-2-sulfophenyl)diazen-1-yl]-5-oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid along with the study available on structurally similar read across substances Trisodium 5-hydroxy-1-(4-sulphophenyl)-4-(4-sulphophenylazo)pyrazole-3-carboxylate (1934-21-0) and 4,4'-bis[4,6-bis(anilino)-1,3,5-triazin-2-yl]aminostilbene-2,2'-disulphonic acid (CAS no: 88-38-0). The predicted data using the OECD QSAR toolbox has also been compared with the experimental studies. The studies are summarized as below –

In a prediction done by SSS (2018) using the OECD QSAR toolbox with log kow as the primary descriptor, the acute oral toxicity was estimated for 4-[(E)-2-(5-{[(2Z,4E)-6-chloro-4-[(3-sulfophenyl)imino]-1,2,3,4-tetrahydro-1,3,5-triazin-2-ylidene]amino}-2-sulfophenyl)diazen-1-yl]-5-oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid (CAS no: 93858-25-4). The LD50 was estimated to be 2298 mg/kg bw, when 3 male and female albino rats were treated with 4-[(E)-2-(5-{[(2Z,4E)-6-chloro-4-[(3-sulfophenyl)imino]-1,2,3,4-tetrahydro-1,3,5-triazin-2-ylidene]amino}-2-sulfophenyl)diazen-1-yl]-5-oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid via oral gavage route.

The above study is supported by Lamia et al.(International Journal of Pharm Tech Research,Vol.9, No.4, pp 364-367, 2016), for the structurally similar read across substance Trisodium 5-hydroxy-1-(4-sulphophenyl)-4-(4-sulphophenylazo)pyrazole-3-carboxylate (1934-21-0). Acute oral toxicity test was conducted in male Sprague- Dawly white mice at the dose concentration of 1250 mg/kg, 2500 mg/kg, 3750 mg/kg, 5000 mg/kg and 6250 mg/kg to 6 animals per dose by oral route. Control animals received distilled water only. The mice were observed for 3 days for the signs and symptoms of toxicity as well as the death rate of each group were recorded. Test material administration at single dose has not been found to be any toxic effects even at higher dose used (6250 mg/Kg BW) at the same time there is no mortality or morbidity was recorded in all grouped animals. Hence, LD50 was considered to be >6250 mg/kg bw when male Sprague- Dawly white mice was treated with Trisodium 5-hydroxy-1-(4-sulphophenyl)-4-(4-sulphophenylazo)pyrazole-3-carboxylate for 3 days via oral route.

This study is further supported by U.S. National Library of Medicine (ChemIDplus, 2017), for the structurally similar read across substance 4,4'-bis[4,6-bis(anilino)-1,3,5-triazin-2-yl]aminostilbene-2,2'-disulphonic acid (CAS no: 88-38-0). Acute oral toxicity study was conducted in rats at the concentration of 10000 mg/kg bw. No mortality was observed in treated rats at 10000 mg/kg bw. Therefore, LD50 was considered to be >10000 mg/kg bw, when rats were treated with4,4'-bis[4,6-bis(anilino)-1,3,5-triazin-2-yl]aminostilbene-2,2'-disulphonic acid via oral route.

Thus, based on the above studies on 4-[(E)-2-(5-{[(2Z,4E)-6-chloro-4-[(3-sulfophenyl)imino]-1,2,3,4-tetrahydro-1,3,5-triazin-2-ylidene]amino}-2-sulfophenyl)diazen-1-yl]-5-oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid (CAS no: 93858-25-4) and it’s read across substances, it can be concluded that LD50 value is >2000 mg/kg bw. Thus, comparing this value with the criteria of CLP regulation, 4-[(E)-2-(5-{[(2Z,4E)-6-chloro-4-[(3-sulfophenyl)imino]-1,2,3,4-tetrahydro-1,3,5-triazin-2-ylidene]amino}-2-sulfophenyl)diazen-1-yl]-5-oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid cannot be classified for acute oral toxicity.

Acute Inhalation toxicity: 

4-[(E)-2-(5-{[(2Z,4E)-6-chloro-4-[(3-sulfophenyl)imino]-1,2,3,4-tetrahydro-1,3,5-triazin-2-ylidene]amino}-2-sulfophenyl)diazen-1-yl]-5-oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid (CAS no: 93858-25-4) has very low vapour pressure (8.83E-39 mmHg), so the potential for the generation of inhalable vapours is very low. Also the normal conditions of use of this substance will not result in aerosols, particles or droplets of an inhalable size, so exposure to humans via the inhalatory route will be highly unlikely and therefore this end point was considered for waiver.

Acute Dermal toxicity:

In different studies, 4-[(E)-2-(5-{[(2Z,4E)-6-chloro-4-[(3-sulfophenyl)imino]-1,2,3,4-tetrahydro-1,3,5-triazin-2-ylidene]amino}-2-sulfophenyl)diazen-1-yl]-5-oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid (CAS no: 93858-25-4) has been investigated for acute dermal toxicity to a greater or lesser extent. Often are the studies based on in vivo experiments in rodents, i.e. most commonly in rabbits and rats for 4-[(E)-2-(5-{[(2Z,4E)-6-chloro-4-[(3-sulfophenyl)imino]-1,2,3,4-tetrahydro-1,3,5-triazin-2-ylidene]amino}-2-sulfophenyl)diazen-1-yl]-5-oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid along with the study available on the structurally similar read across substances Aluminium, 6-hydroxy-5-[(4-sulfophenyl)azo]-2-naphthalenesulfonic acid complex (CAS No. 15790-07-5) and 4,4'-bis[4,6-bis(anilino)-1,3,5-triazin-2-yl]aminostilbene-2,2'-disulphonic acid (CAS no: 88-38-0). The predicted data using the OECD QSAR toolbox has also been compared with the experimental studies. The studies are summarized as below –

In a prediction done by SSS (2018) using the OECD QSAR toolbox with log kow as the primary descriptor, the acute dermal toxicity was estimated for 4-[(E)-2-(5-{[(2Z,4E)-6-chloro-4-[(3-sulfophenyl)imino]-1,2,3,4-tetrahydro-1,3,5-triazin-2-ylidene]amino}-2-sulfophenyl)diazen-1-yl]-5-oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid (CAS no: 93858-25-4). The LD50 was estimated to be 9466 mg/kg bw, when 10 male and female New Zealand White rabbits were treated with 4-[(E)-2-(5-{[(2Z,4E)-6-chloro-4-[(3-sulfophenyl)imino]-1,2,3,4-tetrahydro-1,3,5-triazin-2-ylidene]amino}-2-sulfophenyl)diazen-1-yl]-5-oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid for 24 hours by dermal application occlusively.

This study is supported by Sustainability Support Services (Europe) AB (study no.201303, 2013) was designed and conducted for the structurally similar read across substance Aluminium, 6-hydroxy-5-[(4-sulfophenyl)azo]-2-naphthalenesulfonic acid complex (CAS No. 15790-07-5) in wistar albino rats. The study was conducted under the OECD Guideline-402 for testing of chemicals. In limit test, healthy wistar albino rats of body weight 200±20 gm were selected for study after acclimatization. Approximate 10% back skin of total body surface area was prepared 24 hrs prior to application of test compound. Test drug was applied dermally at the dose of 2000 mg/kg bw for each animal. The treated animals were observed for clinical signs of intoxication. The body weight of all the animals was observed weekly on day 0 (pre treatment), 7th and 14th (post treatment). The Necropsy was performed on all at the termination of the study. After 72 hrs, a confirmatory test was conducted in same species of animals to confirm the limit test of the test compound. Rats were observed for mortality at 30 minutes time interval for first 6 hous on the day of test compund and therafter twice a day for 14 days. All the rats were observed at least twice daily with the purpose of recording any symptoms of ill-health or behavioral changes. The organ which showed gross pathological change during necropsy subjected for histopathological study. No mortality was observed at 2000 mg/kg bw. Animals did not produce any clinical signs of intoxication throughout the period of observation. Animals showed normal gain in body weight on day 7th and 14th as compared to control group. No significant gross pathological changes related to compound toxicity were observed. Skin and hair coat was observed wet. Therefore, it was concluded that the test compound Aluminium, 6-hydroxy-5-[(4-sulfophenyl)azo]-2-naphthalenesulfonic acid complex is non-toxic at the tested dose level 2000 mg/kg body weight. According to criteria of CLP, it comes under the “Category Not classified".

The above study is further supported by U.S. National Library of Medicine (ChemIDplus, 2017) for the structurally similar read across substance 4,4'-bis[4,6-bis(anilino)-1,3,5-triazin-2-yl]aminostilbene-2,2'-disulphonic acid (CAS no: 88-38-0). Acute Dermal toxicity study was conducted in rats at the concentration of 3000 mg/kg bw. No mortality was observed in treated rats at 3000 mg/kg bw. Therefore, LD50 was considered to be >3000 mg/kg bw, when rats were treated with4,4'-bis[4,6-bis(anilino)-1,3,5-triazin-2-yl]aminostilbene-2,2'-disulphonic acid by dermal application.

Thus, based on the above studies on 4-[(E)-2-(5-{[(2Z,4E)-6-chloro-4-[(3-sulfophenyl)imino]-1,2,3,4-tetrahydro-1,3,5-triazin-2-ylidene]amino}-2-sulfophenyl)diazen-1-yl]-5-oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid (CAS no: 93858-25-4) and it’s read across substances, it can be concluded that LD50 value is >2000 mg/kg bw. Thus, comparing this value with the criteria of CLP regulation, 4-[(E)-2-(5-{[(2Z,4E)-6-chloro-4-[(3-sulfophenyl)imino]-1,2,3,4-tetrahydro-1,3,5-triazin-2-ylidene]amino}-2-sulfophenyl)diazen-1-yl]-5-oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid cannot be classified for acute dermal toxicity.

Justification for classification or non-classification

Based on the above studies and prediction on 4-[(E)-2-(5-{[(2Z,4E)-6-chloro-4-[(3-sulfophenyl)imino]-1,2,3,4-tetrahydro-1,3,5-triazin-2-ylidene]amino}-2-sulfophenyl)diazen-1-yl]-5-oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid (CAS no: 93858-25-4) and it’s read across substances, it can be concluded that LD50 value is >2000 mg/kg bw for acute oral and dermal toxicity. Thus, comparing this value with the criteria of CLP regulation, 4-[(E)-2-(5-{[(2Z,4E)-6-chloro-4-[(3-sulfophenyl)imino]-1,2,3,4-tetrahydro-1,3,5-triazin-2-ylidene]amino}-2-sulfophenyl)diazen-1-yl]-5-oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid cannot be classified for acute oral and dermal toxicity.For Acute Inhalation toxicity wavier was added so, not possible to classify.