Sodium 4-(4-(2-hydroxynaphthalenylazo)phenylazo)benzenesulphonate

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

secondary literature

Justification for type of information:

Data is from secondary source

Data source

Reference

Reference Type:

secondary source

Title:

Opinion on Acid Red 33

Author:

Scientific Committee on Consumer Safety

Year:

2007

Bibliographic source:

Opinion on Acid Red 33 ,Scientific Committee on Consumer Safety (SCCS), SCCP/1102/07

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Principles of method if other than guideline:

Skin sensitization study of disodium 5-amino-4-hydroxy-3-(phenylazo)naphthalene-2,7-disulphonate was performed by Maximization test in guinea pig.

GLP compliance:

not specified

Type of study:

Freund's complete adjuvant test

Justification for non-LLNA method:

No data available

Test material

Test material information

Constituent 1

Reference substance name:

Disodium 5-amino-4-hydroxy-3-(phenylazo)naphthalene-2,7-disulphonate

EC Number:

222-656-9

EC Name:

Disodium 5-amino-4-hydroxy-3-(phenylazo)naphthalene-2,7-disulphonate

Cas Number:

3567-66-6

Molecular formula:

C16H13N3O7S2.2Na

IUPAC Name:

disodium 5-amino-4-hydroxy-3-(phenyldiazenyl)naphthalene-2,7-disulfonate

Test material form:

solid

Details on test material:

- Name of test material (as cited in study report): disodium 5-amino-4-hydroxy-3-(phenylazo)naphthalene-2,7-disulphonate
- Molecular formula: C16H13N3O7S2.2Na
- Molecular weight : 467.389 g/mol
- Smiles notation : [Na+].[Na+].Nc1cc(S(=O)(=O)[O])cc2cc(S(=O)(=O)[O-])c(N=Nc3ccccc3)c(O)c12
- Substance type: Organic
- Physical state: Solid

Specific details on test material used for the study:

- Name of test material (as cited in study report): Acid red 33
-IUPAC name: disodium 5-amino-4-hydroxy-3-(phenylazo)naphthalene-2,7-disulphonate
- Molecular formula: C16H13N3O7S2.2Na
- Molecular weight : 467.389 g/mol
- Smiles notation : [Na+].[Na+].Nc1cc(S(=O)(=O)[O])cc2cc(S(=O)(=O)[O-])c(N=Nc3ccccc3)c(O)c12
- Substance type: Organic
- Physical state: Solid

In vivo test system

Test animals

Species:

guinea pig

Strain:

other: Ibm: GOHI

Sex:

female

Details on test animals and environmental conditions:

No data available

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

intradermal

Vehicle:

other: 1% CMC and in an emulsion of FCA/physiological saline

Concentration / amount:

intradermal induction: 5% dilution of test item in 1% CMC and in an emulsion of FCA/physiological saline

Challenge: 25% dilution in 1% CMC

Day(s)/duration:

24 hours

Adequacy of induction:

not specified

Induction 2

Route:

epicutaneous, occlusive

Vehicle:

other: 1% CMC and in an emulsion of FCA/physiological saline

Concentration / amount:

Epidermal induction: 25% dilution in 1% CMC

Day(s)/duration:

48 hours

Adequacy of induction:

non-irritant substance, but skin pre-treated with 10% SDS

Challenge

No.:

#1

Route:

epicutaneous, occlusive

Vehicle:

other: 1% CMC and in an emulsion of FCA/physiological saline

Concentration / amount:

Challenge: 25% dilution in 1% CMC

Day(s)/duration:

24 hours

Adequacy of challenge:

not specified

No. of animals per dose:

Total:15 female
Test group:10
control group:5

Details on study design:

RANGE FINDING TESTS:

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: 2
- Exposure period: 18hr
- Test groups: 10
- Control group: 5
- Site: nuchal region
- Frequency of applications: On day 1 and 8
- Duration: 1 week
- Concentrations:for the intradermal induction: 5% dilution of the test item in 1% CMC and in an emulsion of Freund's Complete Adjuvant (FCA) / physiological saline.
For epidermal induction :25% in 1% CMC

B. CHALLENGE EXPOSURE
- No. of exposures: 1
- Day(s) of challenge:
- Exposure period: 24hr
- Test groups: 10
- Control group: 5
- Site: nuchal region
- Concentrations: 25% in 1% CMC
- Evaluation (hr after challenge): 24 and 48 hr

OTHER : The pre-treatment of the test areas with 10% sodium-laureth-sulfate (SLS), 24 hours prior to application of the test item during epidermal induction. 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.

Challenge controls:

yes

Positive control substance(s):

yes

Remarks:

2-mercaptobenzothiazole

Study design: in vivo (LLNA)

Statistics:

No data available

Results and discussion

Positive control results:

No data available

In vivo (non-LLNA)

Results

Results 1

Reading:

1st reading

Hours after challenge:

24

Group:

other: vehicle control

Dose level:

1%

No. with + reactions:

0

Total no. in group:

5

Clinical observations:

non sensitizer in Control Group

Remarks on result:

no indication of skin sensitisation

Results 2

Reading:

2nd reading

Hours after challenge:

48

Group:

other: vehicle control

Dose level:

1%

No. with + reactions:

0

Total no. in group:

5

Clinical observations:

non sensitizer in Control Group

Remarks on result:

no indication of skin sensitisation

Results 3

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

25%

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

non sensitizer in Test Group

Remarks on result:

no indication of skin sensitisation

Results 4

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

25%

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

non sensitizer in Test Group

Remarks on result:

no indication of skin sensitisation

Any other information on results incl. tables

Skin reactions after the challenge procedure:

	After 24 hours		After 48 hours
	Positive / total	% positive	Positive / total	% positive
Control Group
D&C Red 33, 25% in 1% CMC (left flank)	0 / 5	0	0 / 5	0
1% CMC only (right flank)	0 / 5	0	0 / 5	0
Test Group
D&C Red 33, 25% in 1% CMC (left flank)	0 / 10	0	0 / 10	0
1% CMC only (right flank)	0 / 10	0	0 / 10	0

Applicant's summary and conclusion

Interpretation of results:

other: not sensitising

Conclusions:

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.

Executive summary:

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.