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Diss Factsheets

Administrative data

Description of key information

Skin sensitization:

The skin sensitization potential of Sodium 4-(4-(2-hydroxynaphthalenylazo)phenylazo)benzenesulphonate was estimated using OECD QSAR toolbox v 3.4 with logPow as the primary descriptor. Sodium 4-(4-(2-hydroxynaphthalenylazo)phenylazo)benzenesulphonate was estimated to be not sensitizing to the skin of  guinea pig. Based on the estimated results, Sodium 4-(4-(2-hydroxynaphthalenylazo)phenylazo)benzenesulphonate can be considered to be not sensitizing to skin and can be classified under the category “ Not Classified ” as per CLP regulation.

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records
Reference
Endpoint:
skin sensitisation: in vivo (non-LLNA)
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 3.4 and QMRF report has been attached
Qualifier:
according to guideline
Guideline:
other: estimated data
Principles of method if other than guideline:
Prediction was done by using OECD QSAR toolbox v3.4
GLP compliance:
not specified
Type of study:
guinea pig maximisation test
Justification for non-LLNA method:
Not specified
Specific details on test material used for the study:
- Name of test material (IUPAC name): Sodium 4-(4-(2-hydroxynaphthalenylazo)phenylazo)benzenesulphonate
- Common name: Acid Red 151
- Molecular formula: C22H15N4O4S.Na
- Molecular weight: 455.448 g/mol
-Physical state: red to brown powder
- Smiles notation: c12c(\N=N\c3ccc(\N=N\c4ccc(S(O)(=O)=O)cc4)cc3)c(ccc1cccc2)O.[Na+]
- InChl: 1S/C22H16N4O4S.Na/c27-21-14-5-15-3-1-2-4-20(15)22(21)26-25-17-8-6-16(7-9-17)23-24-18-10-12-19(13-11-18)31(28,29)30;/h1-14,27H,(H,28,29,30);/q;+1/b24-23+,26-25+;
- Substance type: Organic
Species:
guinea pig
Strain:
not specified
Sex:
not specified
Details on test animals and environmental conditions:
No data available
Route:
other: Not specified
Vehicle:
not specified
Concentration / amount:
Not specified
Day(s)/duration:
Not specified
Adequacy of induction:
not specified
No.:
#1
Route:
other: Not specified
Vehicle:
not specified
Concentration / amount:
Not specified
Day(s)/duration:
Not specified
Adequacy of challenge:
not specified
No. of animals per dose:
Not specified
Details on study design:
Not specified
Challenge controls:
Not specified
Positive control substance(s):
not specified
Reading:
1st reading
Group:
test chemical
Dose level:
Not specified
Clinical observations:
no skin allergic reaction estimated
Remarks on result:
no indication of skin sensitisation

The prediction was based on dataset comprised from the following descriptors: "Skin Sensitisation"
Estimation method: Takes highest mode value from the 7 nearest neighbours
Domain  logical expression:Result: In Domain

((((("a" or "b" or "c" )  and ("d" and ( not "e") )  )  and "f" )  and ("g" and ( not "h") )  )  and ("i" and "j" )  )

Domain logical expression index: "a"

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

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as Strong binder, OH group by Estrogen Receptor Binding

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as Acid moiety AND Phenols AND Salt by Aquatic toxicity classification by ECOSAR

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as No alert found by Protein binding by OASIS v1.4

Domain logical expression index: "e"

Referential boundary: The target chemical should be classified as Acylation OR Acylation >> Acylation involving an activated (glucuronidated) carboxamide group OR Acylation >> Acylation involving an activated (glucuronidated) carboxamide group >> Carboxylic Acid Amides OR Acylation >> Acylation involving an activated (glucuronidated) ester group OR Acylation >> Acylation involving an activated (glucuronidated) ester group >> Arenecarboxylic Acid Esters OR Acylation >> Acylation involving an activated (glucuronidated) sulfonamide group OR Acylation >> Acylation involving an activated (glucuronidated) sulfonamide group >> Arenesulfonamides OR Acylation >> Direct acylation involving a leaving group OR Acylation >> Direct acylation involving a leaving group >> Carboxylic Acid Amides OR Acylation >> Ester aminolysis OR Acylation >> Ester aminolysis >> Amides OR AN2 OR AN2 >> Michael addition to activated double bonds OR AN2 >> Michael addition to activated double bonds >> alpha,beta-Unsaturated Carbonyls and Related Compounds 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 >> Michael-type addition to quinoid structures  OR AN2 >> Michael-type addition to quinoid structures  >> Carboxylic Acid Amides OR AN2 >> Michael-type addition to quinoid structures  >> N-Substituted Aromatic Amines OR AN2 >> Michael-type addition to quinoid structures  >> Substituted Anilines OR AN2 >> Michael-type addition to quinoid structures  >> Substituted Phenols OR AN2 >> Nucleophilic addition at polarized N-functional double bond OR AN2 >> Nucleophilic addition at polarized N-functional double bond >> Arenesulfonamides 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 formation with carbonyl compounds OR Schiff base formation >> Schiff base formation with carbonyl compounds >> Aromatic carbonyl compounds OR Schiff base formation >> Schiff base on pyrazolones and pyrazolidinones OR Schiff base formation >> Schiff base on pyrazolones and pyrazolidinones >> 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 v1.4

Domain logical expression index: "f"

Referential boundary: The target chemical should be classified as High (Class III) by Toxic hazard classification by Cramer (extension) ONLY

Domain logical expression index: "g"

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

Domain logical expression index: "h"

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

Domain logical expression index: "i"

Parametric boundary:The target chemical should have a value of log Kow which is >= -1.68

Domain logical expression index: "j"

Parametric boundary:The target chemical should have a value of log Kow which is <= 6.46

Interpretation of results:
other: Not sensitising
Conclusions:
Sodium 4-(4-(2-hydroxynaphthalenylazo)phenylazo)benzenesulphonate was considered to be not sensitizing .
Executive summary:

The skin sensitization potential of Sodium 4-(4-(2-hydroxynaphthalenylazo)phenylazo)benzenesulphonate was estimated using OECD QSAR toolbox v 3.4 with logPow as the primary descriptor. Sodium 4-(4-(2-hydroxynaphthalenylazo)phenylazo)benzenesulphonate was estimated to be not sensitizing to the skin of  guinea pig. Based on the estimated results, Sodium 4-(4-(2-hydroxynaphthalenylazo)phenylazo)benzenesulphonate can be considered to be not sensitizing to skin and can be classified under the category “ Not Classified ” as per CLP regulation.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not sensitising)
Additional information:

Skin sensitization:

In different studies, Sodium 4-(4-(2-hydroxynaphthalenylazo)phenylazo) benzene sulphonate has been investigated for potential for skin sensitization to a greater or lesser extent. The studies are based on in vivo experiments in rabbits along with human data for target chemical Sodium 4-(4-(2-hydroxynaphthalenylazo)phenylazo)benzenesulphonate and its structurally similar read across substances Disodium 5-amino-4-hydroxy-3-(phenylazo) naphthalene-2,7-disulphonate[CAS: 3567-66-6] and Disodium 5-acetamido-4-hydroxy-3-(phenyldiazenyl)naphthalene-2,7-disulfonate (3734-67-6 ). The predicted data using the OECD QSAR toolbox has also been compared with the experimental data.

The skin sensitization potential of Sodium 4-(4-(2 hydroxynaphthalenylazo)phenylazo) benzenesulphonate was estimated using OECD QSAR toolbox v 3.4 with log Pow as the primary descriptor. Sodium 4-(4-(2-hydroxynaphthalenylazo)phenylazo)benzenesulphonate was estimated to be not sensitizing to the skin of  guinea pig. Based on the estimated results, Sodium 4-(4-(2-hydroxynaphthalenylazo)phenylazo)benzenesulphonate can be considered to be not sensitizing to skin and can be classified under the category “ Not Classified ” as per CLP regulation.

The above prediction was supported by experimental result summarized in Opinion on Acid Red 33 ,Scientific Committee on Consumer Safety (SCCS), SCCP/1102/07 for thestructurally similar read across substance Disodium 5-amino-4-hydroxy-3-(phenylazo) naphthalene-2,7-disulphonate[CAS: 3567-66-6]

A maximisation test of Acid red 33 was performed in 15 (10 test and 5 control) female guinea pigs. The intradermal induction of sensitisation in the test group was performed in the nuchal region with a 5% dilution of the test item in 1% CMC and in an emulsion of Freund's Complete Adjuvant (FCA) / physiological saline. The epidermal induction of sensitisation was conducted for 18 hours under occlusion with the test item at 25% in 1% CMC one week after the intradermal induction and following pre-treatment of the test areas with 10% sodium-laureth-sulfate (SLS), 24 hours prior to application of the test item. The animals of the control group were intradermally induced with 1% CMC and FCA/physiological saline and epidermally induced with 1% CMC under occlusion following pre-treatment with 10% SLS. Cutaneous reactions were evaluated at 24 and 48 hours after removal of the dressing. No skin sensitization reaction was observed. Hence, disodium 5-amino-4-hydroxy-3-(phenylazo)naphthalene-2,7-disulphonate was considered to be not skin sensitizing in guinea pig.

The above experimental result was further supported by experimental study summarized in Scientific Committee on Cosmetology (seventh series), 1988 for the structurally similar read across substanceDisodium 5-acetamido-4-hydroxy-3-(phenyldiazenyl)naphthalene-2,7-disulfonate (3734-67-6 ).

A sensitization test was carried out in guinea pigs to determined the sensitizing potential of RED 2G. Guinea pigs were given two times 4 intradermal injections of 0.1 ml of a 7.5% solution in saline during the induction phase.14 days after second injection, a challenge exposure was conducted. In the challenge exposure, single intradermal injection of a 3% solution in saline was administered to the guinea pigs.

Signs of sensitization were not observed. Hence RED 2G (3734-67-6)was considered  to be non sensitizing after challenge exposure in guinea pig.

Based on the available data for the target as well as it read across substances;and applying the weight of evidence approach, it can be concluded that Sodium 4-(4-(2-hydroxynaphthalenylazo)phenylazo) benzene sulphonate was not sensitizing to skin. Itcan be classified under the category “Not Classified” as per CLP regulation

Respiratory sensitisation

Endpoint conclusion
Endpoint conclusion:
no study available

Justification for classification or non-classification

Based on the available data for the target as well as it read across substances;and applying the weight of evidence approach, it can be concluded that Sodium 4-(4-(2-hydroxynaphthalenylazo)phenylazo) benzene sulphonate was not sensitizing to skin. Itcan be classified under the category “Not Classified” as per CLP regulation