Disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl]azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-)

Endpoint summary

Description of key information

Acute oral toxicity: 

Acute oral toxicity dose (LD50) of disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl]azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-)(CAS no: 6798-03-4) was predicted based on OECD QSAR toolbox, the value estimated to be 7884 mg/kg bw and different studies available on structurally similar read across substances Tetra sodium 1-acetamido-2-hydroxy-3-(4-((4-sulphonatophenylazo)-7-sulphonato-1-naphthylazo)) naphthalene-4,6-disulphonate (CAS No. 2519-30-4), the LD50 was considered to be >2000 mg/kg bw and Trisodium 3-hydroxy-4-(4'-sulphonatonaphthylazo) naphthalene-2,7- disulphonate (CAS no: 915-67-3), the LD50 was considered to be >2000 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, disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl] azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-) cannot be classified for acute oral toxicity.

Acute Dermal toxicity: 

Acute Dermal toxicity dose (LD50) for disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl] azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-)(CAS no: 6798-03-4) was predicted based on OECD QSAR toolbox, the value estimated to be 11253 mg/kg bw and different studies available for the structurally similar read across substances Tetra sodium 1-acetamido-2-hydroxy-3-(4-((4-sulphonatophenylazo)-7-sulphonato-1-naphthylazo))naphthalene-4,6-disulphonate (CAS No. 2519-30-4) LD50 was considered to be >2000 mg/kg bw and Disodium 4-hydroxy-3-[(4-sulfonato-1-naphthyl)diazenyl]naphthalene-1-sulfonate (3567-69-9)LD50 was considered to be >2000 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, disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl] azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-) 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: disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl]azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-)
InChI:1S/C32H25N7O14S4.2Cu.2Na/c33-54(44,45)19-3-7-25(40)23(13-19)36-38-29-27(56(48,49)50)11-15-9-17(1-5-21(15)31(29)42)35-18-2-6-22-16(10-18)12-28(57(51,52)53)30(32(22)43)39-37-24-14-20(55(34,46)47)4-8-26(24)41;;;;/h1-14,35,40-43H,(H2,33,44,45)(H2,34,46,47)(H,48,49,50)(H,51,52,53);;;;/q;2*+2;2*+1/p-6/b38-36+,39-37+;;;;
SMILES:NS(=O)(=O)c1ccc(O{-}.[Na]{+})c(N=Nc2c3cc4cc(ccc4c2O{-}.[Na]{+})Nc2ccc4c(c2)cc(c2c4O{-}.[Cu]{2+}.O{-}c4ccc(S(N)(=O)=O)cc4N=N2)S(=O)(=O)O{-}.[Cu]{2+}.O{-}S3(=O)=O)c1
Mol. formula: C32H19Cu2N7Na2O14S4
Molecular Weight: 1026.87 g/mole

Species:

rat

Strain:

Sprague-Dawley

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:

7884 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:

7 884 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" )  and "e" )  and "f" )  and "g" )  and "h" )  and ("i" and ( not "j") )  )  and "k" )  and "l" )  and ("m" and ( not "n") )  )  and ("o" and ( not "p") )  )  and ("q" and "r" )  )

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as Amine OR Anion OR Aromatic compound OR Azo compound OR Cation OR Secondary amine OR Secondary aromatic amine OR Sulfonamide OR Sulfonic acid derivative by Organic functional groups, Norbert Haider (checkmol) ONLY

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as Aliphatic Nitrogen, one aromatic attach [-N] OR Aliphatic Nitrogen, two aromatic attach [-N-] OR Aromatic Carbon [C] OR Azo [-N=N-] OR Miscellaneous metal [Ni, Cu, Zr, Be] OR Miscellaneous sulfide (=S) or oxide (=O) OR Nitrogen, two or tree olefinic attach [>N-] OR Olefinic carbon [=CH- or =C<] OR Oxygen, one aromatic attach [-O-] OR Suflur {v+4} or {v+6} OR Sulfamide, aromatic attach [-SO2-N] OR Sulfonate, aromatic attach [-SO2-O] OR Sulfonyl amide, aromatic attach [-S(=O)N-] OR Sulfur, nitrogen attach [-S-] by Organic functional groups (US EPA) ONLY

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as Aromatic amine OR Aryl OR Azo OR Fused carbocyclic aromatic OR Overlapping groups OR Phenol OR Sulfonamide OR Sulfonic acid by Organic Functional groups (nested) ONLY

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as Aromatic amine OR Aryl OR Azo OR Fused carbocyclic aromatic OR Naphtalene OR Phenol OR Sulfonamide OR Sulfonic acid by Organic Functional groups ONLY

Domain logical expression index: "e"

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: "f"

Referential boundary: The target chemical should be classified as Class 5 (Not possible to classify according to these rules) by Acute aquatic toxicity classification by Verhaar (Modified) ONLY

Domain logical expression index: "g"

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

Domain logical expression index: "h"

Similarity boundary:Target: NS(=O)(=O)c1ccc(O{-}.[Na]{+})c(N=Nc2c3cc4cc(ccc4c2O{-}.[Na]{+})Nc2ccc4c(c2)cc(c2c4O{-}.[Cu]{2+}.O{-}c4ccc(S(N)(=O)=O)cc4N=N2)S(=O)(=O)O{-}.[Cu]{2+}.O{-}S3(=O)=O)c1
Threshold=20%,
Dice(Atom centered fragments)
Atom type; Count H attached; Hybridization

Domain logical expression index: "i"

Referential boundary: The target chemical should be classified as Not categorized by Repeated dose (HESS)

Domain logical expression index: "j"

Referential boundary: The target chemical should be classified as 3-Methylcholantrene (Hepatotoxicity) Alert OR Aliphatic nitriles (Hepatotoxicity) Rank B OR Benzene/ Naphthalene sulfonic acids (Less susceptible) Rank C OR Benzenesulfonamides (Toxicity to urinary system) Rank B OR Tamoxifen (Hepatotoxicity) Alert OR Thiocarbamates/Sulfides (Hepatotoxicity) No rank by Repeated dose (HESS)

Domain logical expression index: "k"

Referential boundary: The target chemical should be classified as Aliphatic Nitrogen, one aromatic attach [-N] AND Aliphatic Nitrogen, two aromatic attach [-N-] AND Aromatic Carbon [C] AND Azo [-N=N-] AND Miscellaneous metal [Ni, Cu, Zr, Be] AND Miscellaneous sulfide (=S) or oxide (=O) AND Nitrogen, two or tree olefinic attach [>N-] AND Olefinic carbon [=CH- or =C<] AND Oxygen, one aromatic attach [-O-] AND Suflur {v+4} or {v+6} AND Sulfamide, aromatic attach [-SO2-N] AND Sulfonate, aromatic attach [-SO2-O] AND Sulfonyl amide, aromatic attach [-S(=O)N-] AND Sulfur, nitrogen attach [-S-] by Organic functional groups (US EPA) ONLY

Domain logical expression index: "l"

Referential boundary: The target chemical should be classified as Amine AND Anion AND Aromatic compound AND Azo compound AND Cation AND Secondary amine AND Secondary aromatic amine AND Sulfonamide AND Sulfonic acid derivative by Organic functional groups, Norbert Haider (checkmol) ONLY

Domain logical expression index: "m"

Referential boundary: The target chemical should be classified as Not known precedent reproductive and developmental toxic potential by DART scheme v.1.0

Domain logical expression index: "n"

Referential boundary: The target chemical should be classified as Metal atoms were identified by DART scheme v.1.0

Domain logical expression index: "o"

Referential boundary: The target chemical should be classified as Metals, oxidative stress (Nongenotox) AND Structural alert for nongenotoxic carcinogenicity by Carcinogenicity (genotox and nongenotox) alerts by ISS

Domain logical expression index: "p"

Referential boundary: The target chemical should be classified as No alert found by Carcinogenicity (genotox and nongenotox) alerts by ISS

Domain logical expression index: "q"

Parametric boundary:The target chemical should have a value of log Kow which is >= -2.63

Domain logical expression index: "r"

Parametric boundary:The target chemical should have a value of log Kow which is <= 0.0527

Interpretation of results:

other: Not classified

Conclusions:

LD50 was estimated to be 7884 mg/kg bw, when 10 male and female Sprague-Dawley rats were treated with disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl] azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-)(CAS no: 6798-03-4) via oral gavage route.

Executive summary:

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 disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl] azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-)(CAS no: 6798-03-4). The LD50 was estimated to be 7884 mg/kg bw, when 10 male and female Sprague-Dawley rats were treated with disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl] azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-) via oral gavage route.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

7 884 mg/kg bw

Quality of whole database:

Data is Klimisch 2 and from QSAR toolbox 3.3.

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

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: disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl]azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-)
InChI:1S/C32H25N7O14S4.2Cu.2Na/c33-54(44,45)19-3-7-25(40)23(13-19)36-38-29-27(56(48,49)50)11-15-9-17(1-5-21(15)31(29)42)35-18-2-6-22-16(10-18)12-28(57(51,52)53)30(32(22)43)39-37-24-14-20(55(34,46)47)4-8-26(24)41;;;;/h1-14,35,40-43H,(H2,33,44,45)(H2,34,46,47)(H,48,49,50)(H,51,52,53);;;;/q;2*+2;2*+1/p-6/b38-36+,39-37+;;;;
SMILES:NS(=O)(=O)c1ccc(O{-}.[Na]{+})c(N=Nc2c3cc4cc(ccc4c2O{-}.[Na]{+})Nc2ccc4c(c2)cc(c2c4O{-}.[Cu]{2+}.O{-}c4ccc(S(N)(=O)=O)cc4N=N2)S(=O)(=O)O{-}.[Cu]{2+}.O{-}S3(=O)=O)c1
Mol. formula: C32H19Cu2N7Na2O14S4
Molecular Weight: 1026.87 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:

11253 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:

11 253 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" )  and "e" )  and "f" )  and ("g" and ( not "h") )  )  and ("i" and ( not "j") )  )  and ("k" and ( not "l") )  )  and "m" )  and ("n" and ( not "o") )  )  and "p" )  and "q" )  and ("r" and "s" )  )

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as Amine OR Anion OR Aromatic compound OR Azo compound OR Cation OR Secondary amine OR Secondary aromatic amine OR Sulfonamide OR Sulfonic acid derivative by Organic functional groups, Norbert Haider (checkmol) ONLY

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as Aliphatic Nitrogen, one aromatic attach [-N] OR Aliphatic Nitrogen, two aromatic attach [-N-] OR Aromatic Carbon [C] OR Azo [-N=N-] OR Miscellaneous metal [Ni, Cu, Zr, Be] OR Miscellaneous sulfide (=S) or oxide (=O) OR Nitrogen, two or tree olefinic attach [>N-] OR Olefinic carbon [=CH- or =C<] OR Oxygen, one aromatic attach [-O-] OR Suflur {v+4} or {v+6} OR Sulfamide, aromatic attach [-SO2-N] OR Sulfonate, aromatic attach [-SO2-O] OR Sulfonyl amide, aromatic attach [-S(=O)N-] OR Sulfur, nitrogen attach [-S-] by Organic functional groups (US EPA) ONLY

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as Aromatic amine OR Aryl OR Azo OR Fused carbocyclic aromatic OR Overlapping groups OR Phenol OR Sulfonamide OR Sulfonic acid by Organic Functional groups (nested) ONLY

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as Aromatic amine OR Aryl OR Azo OR Fused carbocyclic aromatic OR Naphtalene OR Phenol OR Sulfonamide OR Sulfonic acid by Organic Functional groups ONLY

Domain logical expression index: "e"

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: "f"

Referential boundary: The target chemical should be classified as No alert found by DNA binding by OECD 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, without OH or NH2 group by Estrogen Receptor Binding

Domain logical expression index: "i"

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

Domain logical expression index: "j"

Referential boundary: The target chemical should be classified as Alkaline Earth OR Halogens OR Metalloids OR Metals OR Rare Earth by Groups of elements

Domain logical expression index: "k"

Referential boundary: The target chemical should be classified as Group 1 - Alkali Earth Li,Na,K,Rb,Cs,Fr AND Group 11 - Trans.Metals Cu,Ag,Au AND Group 14 - Carbon C AND Group 15 - Nitrogen N AND Group 16 - Oxygen O AND Group 16 - Sulfur S by Chemical elements

Domain logical expression index: "l"

Referential boundary: The target chemical should be classified as Group 12 - Trans.Metals Zn,Cd,Hg OR Group 15 - Phosphorus P OR Group 6 - Trans.Metals Cr,Mo,W OR Group 9 - Trans.Metals Co,Rh,Ir by Chemical elements

Domain logical expression index: "m"

Similarity boundary:Target: NS(=O)(=O)c1ccc(O{-}.[Na]{+})c(N=Nc2c3cc4cc(ccc4c2O{-}.[Na]{+})Nc2ccc4c(c2)cc(c2c4O{-}.[Cu]{2+}.O{-}c4ccc(S(N)(=O)=O)cc4N=N2)S(=O)(=O)O{-}.[Cu]{2+}.O{-}S3(=O)=O)c1
Threshold=20%,
Dice(Atom centered fragments)
Atom type; Count H attached; Hybridization

Domain logical expression index: "n"

Referential boundary: The target chemical should be classified as Not categorized by Repeated dose (HESS)

Domain logical expression index: "o"

Referential boundary: The target chemical should be classified as Aliphatic nitriles (Hepatotoxicity) Rank B OR Oxyphenistain (Hepatotoxicity) Alert OR Phenols (Mucous membrane irritation) Rank C by Repeated dose (HESS)

Domain logical expression index: "p"

Referential boundary: The target chemical should be classified as Amine AND Anion AND Aromatic compound AND Azo compound AND Cation AND Secondary amine AND Secondary aromatic amine AND Sulfonamide AND Sulfonic acid derivative by Organic functional groups, Norbert Haider (checkmol) ONLY

Domain logical expression index: "q"

Referential boundary: The target chemical should be classified as Amine AND Anion AND Aromatic compound AND Azo compound AND Cation AND Secondary amine AND Secondary aromatic amine AND Sulfonamide AND Sulfonic acid derivative by Organic functional groups, Norbert Haider (checkmol) ONLY

Domain logical expression index: "r"

Parametric boundary:The target chemical should have a value of log Kow which is >= -2.68

Domain logical expression index: "s"

Parametric boundary:The target chemical should have a value of log Kow which is <= -0.788

Interpretation of results:

other: Not classified

Conclusions:

LD50 was estimated to be 11253 mg/kg bw, when 10 male and female New Zealand White rabbits were treated with disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl] azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-)(CAS no: 6798-03-4) for 24 hours by dermal application occlusively.

Executive summary:

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 disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl] azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-)(CAS no: 6798-03-4). The LD50 was estimated to be 11253 mg/kg bw, when 10 male and female New Zealand White rabbits were treated with disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl] azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-) for 24 hours by dermal application occlusively.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

11 253 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, disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl] azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-)(CAS no: 6798-03-4) 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 disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl] azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-) along with the study available on structurally similar read across substances Tetrasodium 1-acetamido-2-hydroxy-3-(4-((4-sulphonatophenylazo)-7-sulphonato-1-naphthylazo))naphthalene-4,6-disulphonate (CAS No. 2519-30-4) and Trisodium 3-hydroxy-4-(4'-sulphonatonaphthylazo)naphthalene-2,7- disulphonate (CAS no: 915-67-3). 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 disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl] azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-)(CAS no: 6798-03-4). The LD50 was estimated to be 7884 mg/kg bw, when 10 male and female Sprague-Dawley rats were treated with disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl] azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-) via oral gavage route.

The above study is supported by Sustainability Support Services (Europe) AB (study no.18817, 2016) was designed and conducted for the structurally similar read across substance Tetrasodium 1-acetamido-2-hydroxy-3-(4-((4-sulphonatophenylazo)-7-sulphonato-1-naphthylazo))naphthalene-4,6-disulphonate (CAS No. 2519-30-4) in Sprague Dawley rats. Initially, three female animals were treated at the dose level of 300 mg/kg body weight of the test item (Step - I). Administration of the test item at 300 mg/kg did not result in any signs of toxicity and mortality at 24 hours after the dosing. As no mortality was observed at 24 hours after the dosing, three female animals were added to the study and treated with the same dose of 300 mg/kg of the test item (Step - II). Administration of the test item at 300 mg/kg did not result in any signs of toxicity and mortality after the dosing. No mortality was observed at 300 mg/kg dose group, hence additional three female animals were treated with the higher dose of 2000 mg/kg of the test item (Step - I). Administration of the test item at 2000 mg/kg resulted in diarrhoea (black colour stools) in all animals with onset at 2 hours and no mortality after the dosing. As no mortality were observed at 24 hours after the dosing, hence additional three female animals were treated with the higher dose of 2000 mg/kg of the test item (Step - II). Administration of the test item at 2000 mg/kg resulted in diarrhoea (black colour stools) in all animals with onset at 4 hours and no mortality after the dosing. All animals from 300 mg/kg and 2000 mg/kg dose groups survived through the study period of 14 days. Staining of the stool is attributed to the black colour of the test item. Gross pathological examination did not reveal any abnormalities in animals from 300 mg/kg and 2000 mg/kg dose groups. The acute oral LD50 of Tetra sodium 1-acetamido-2-hydroxy-3-(4-((4-sulphonatophenylazo)-7-sulphonato-1-naphthylazo)) naphthalene-4,6-disulphonate (CAS No. 2519-30-4) was >2000 mg/kg body weight. Thus, it was concluded that the acute toxicity study of Tetra sodium 1-acetamido-2-hydroxy-3-(4-((4-sulphonatophenylazo)-7-sulphonato-1-naphthylazo))naphthalene-4,6-disulphonate (CAS No. 2519-30-4), when administered via oral route in Sprague Dawley rats falls into the “Category Not classified” criteria of CLP.

This study is further supported by Sasakiet al.(Mutation Research 519 (2002) 103–119), for the structurally similar read across substance Trisodium 3-hydroxy-4-(4'-sulphonatonaphthylazo)naphthalene-2,7- disulphonate (CAS no: 915-67-3). The acute oral toxicity study was conducted in 4 - 5 male DDY mice at the concentration of 2000 mg/kg bw according to comet assay. The given test chemical was dissolve in physiological saline and administered as 0.5ml x LD50 or 2000 mg/kg bw in mice. No mortality was observed at 2000 mg/kg bw in treated mice. Therefore, LD50 was considered to be >2000 mg/kg bw, when male DDY mice were treated with Trisodium 3-hydroxy-4-(4'-sulphonatonaphthylazo) naphthalene-2,7- disulphonate via oral route.

Thus, based on the above studies on disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl] azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-)(CAS no: 6798-03-4) 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, disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl] azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-) cannot be classified for acute oral toxicity.

Acute Dermal toxicity:

In different studies, disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl] azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-)(CAS no: 6798-03-4) 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 disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl] azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-) along with the study available on the structurally similar read across substances Tetra sodium 1-acetamido-2-hydroxy-3-(4-((4-sulphonatophenylazo)-7-sulphonato-1-naphthylazo))naphthalene-4,6-disulphonate (CAS No. 2519-30-4) and Disodium 4-hydroxy-3-[(4-sulfonato-1-naphthyl)diazenyl]naphthalene-1-sulfonate (3567-69-9). 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 disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl] azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-)(CAS no: 6798-03-4). The LD50 was estimated to be 11253 mg/kg bw, when 10 male and female New Zealand White rabbits were treated with disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl] azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-) for 24 hours by dermal application occlusively.

This study is supported by Sustainability Support Services (Europe) AB (study no.18818, 2016) was designed and conducted for the structurally similar read across substance Tetra sodium 1-acetamido-2-hydroxy-3-(4-((4-sulphonatophenylazo)-7-sulphonato-1-naphthylazo))naphthalene-4,6-disulphonate (CAS No. 2519-30-4) in Sprague Dawley rats. The test item was applied to shorn skin of 5 male and 5 female animals at 2000 mg/kg body weight. Administration of the test item at 2000 mg/kg did not result in any skin reaction at the site of application during the study period of 14 days. Administration of the test item did not result in any signs of toxicity and mortality during the study period of 14 days. Animals exhibited normal body weight gain through the study period of 14 days. Gross pathological examination did not reveal any abnormalities attributable to the treatment. It was concluded that the acute dermal median lethal dose (LD50) of Tetra sodium 1-acetamido-2-hydroxy-3-(4-((4-sulphonatophenylazo)-7-sulphonato-1-naphthylazo))naphthalene-4,6-disulphonate, when administered to male and female Sprague Dawley rats was found to be >2000 mg/kg body weight. Thus, according to CLP criteria for acute toxicity rating for the chemicals, it infers that Tetra sodium 1-acetamido-2-hydroxy-3-(4-((4-sulphonatophenylazo)-7-sulphonato-1-naphthylazo))naphthalene-4,6-disulphonate (CAS No. 2519-30-4) does not classify as an acute dermal toxicant. CLP Classification: “Not classified”.

The above study is further supported by Sustainability Support Services (Europe) AB (study no.18824, 2016) was designed and conducted for the structurally similar read across substance Disodium 4-hydroxy-3-[(4-sulfonato-1-naphthyl)diazenyl]naphthalene-1-sulfonate (3567-69-9) in Sprague Dawley rats. The test item was applied to shorn skin of 5 male and 5 female animals at 2000 mg/kg body weight. Administration of the test item at 2000 mg/kg did not result in any skin reaction at the site of application during the study period of 14 days. Administration of the test item did not result in any signs of toxicity and mortality during the study period of 14 days. Animals exhibited normal body weight gain through the study period of 14 days. Gross pathological examination did not reveal any abnormalities attributable to the treatment. It was concluded that the acute dermal median lethal dose (LD50) of Disodium 4-hydroxy-3-[(4-sulfonato-1-naphthyl)diazenyl]naphthalene-1-sulfonate (3567-69-9) supplied bySustainability Support Services (Europe) AB, Sweden, when administered to male and female Sprague Dawley rats was found to be >2000 mg/kg body weight. Thus by considering the CLP criteria for acute toxicity rating for the chemicals, it infers that Disodium 4-hydroxy-3-[(4-sulfonato-1-naphthyl)diazenyl]naphthalene-1-sulfonate does not exhibits acute toxicity by the dermal route.

Thus, based on the above studies on disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl] azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-)(CAS no: 6798-03-4) 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, disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl] azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-) cannot be classified for acute dermal toxicity.

Justification for classification or non-classification

Based on the above studies and prediction on disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl] azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-)(CAS no: 6798-03-4) 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, disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl] azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-) cannot be classified for acute oral and dermal toxicity.