1-(2,4-dimethylphenylazo)-2-naphthol

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Justification for type of information:

Data is from peer reviewed journal

Data source

Reference

Reference Type:

publication

Title:

Pigmented contact dermatitis from azo dyes. I. Cross-sensitivity in humans

Author:

TAKEHITO KGZUKA, MINORU TASHIR0, SHIGEHARU SANO, KEIICHI FUJIMOTO, YUMI NAKAMURA, SEIICHI HASHIMOTO AND GEN NAKAMINAM

Year:

1980

Bibliographic source:

Contact Dermatitis; Volume 6; Pg. no. 330-336; 1980

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: as mentioned below

Principles of method if other than guideline:

Skin sensitization study was performed in human patients suffering from pigmented contact dermatitis caused by the commercial Brilliant Lake Red R to evaluate whether the test substance Sudan II is a potential skin sensitizer or not.

GLP compliance:

not specified

Type of study:

patch test

Justification for non-LLNA method:

Skin sensitization study was performed in human patients suffering from pigmented contact dermatitis.

Test material

Test material information

Constituent 1

Reference substance name:

1- (2, 4-dimethylphenylazo)-2-naphthol

IUPAC Name:

1- (2, 4-dimethylphenylazo)-2-naphthol

Constituent 2

Reference substance name:

1-(2,4-dimethylphenylazo)-2-naphthol

EC Number:

221-490-4

EC Name:

1-(2,4-dimethylphenylazo)-2-naphthol

Cas Number:

3118-97-6

Molecular formula:

C18H16N2O

IUPAC Name:

1-(2,4-dimethylphenylazo)-2-naphthol

Test material form:

solid: crystalline

Details on test material:

- Name of test material (as cited in study report): Sudan II
- Molecular formula (if other than submission substance): C18H16N2O
- Molecular weight (if other than submission substance): 276.337 g/mol
- Substance type: Organic
- Physical state: Solid
- Purity: No data available
- Impurities (identity and concentrations): No data available

Specific details on test material used for the study:

- Name of test material (as cited in study report): C.I. Solvent orange 7
- Molecular formula: C18H16N2O
- Molecular weight : 276.337 g/mol
- Substance type: Organic
- Physical state: Solid
- Smiles : Cc1ccc(N=Nc2c(O)ccc3ccccc23)c(C)c1
- InChI: 1S/C18H16N2O/c1-12-7-9-16(13(2)11-12)19-20-18-15-6-4-3-5-14(15)8-10-17(18)21/h3-11,21H,1-2H3/b20-19+

In vivo test system

Test animals

Species:

human

Strain:

other: not applicable

Sex:

not specified

Details on test animals and environmental conditions:

No data available

Study design: in vivo (non-LLNA)

Induction

Route:

epicutaneous, occlusive

Vehicle:

petrolatum

Concentration / amount:

1% in petrolatum

Challenge

Route:

epicutaneous, occlusive

Vehicle:

petrolatum

Concentration / amount:

1% in petrolactum

No. of animals per dose:

8

Details on study design:

OTHER: The tests were performed with Finn Chambers® on Scanpor® (Epitest, Ltd. Oy). The application was performed on the back for 2 days. Readings were made according to the ICDRG classification 24 h after the patches were removed.

Challenge controls:

No data available

Positive control substance(s):

not specified

Results and discussion

In vivo (non-LLNA)

Results

Group:

test chemical

Dose level:

1%

No. with + reactions:

2

Total no. in group:

8

Clinical observations:

Positive effects observed

Remarks on result:

positive indication of skin sensitisation

Any other information on results incl. tables

Other details not known

Applicant's summary and conclusion

Interpretation of results:

other: sensitising

Conclusions:

Positive reactions were seen in 2 out of total 8 cases. Thus the test chemical 1-[(2,4-dimethylphenyl)diazenyl]-2-naphthol (CAS No: 3118-97-6) was considered to be sensitizing in human patients suffering from pigmented contact dermatitis caused by the commercial Brilliant Lake Red R.

Executive summary:

Skin sensitization study was performed in human patients suffering from pigmented contact dermatitis caused by the commercial Brilliant Lake Red R to evaluate the skin sensitizing potential of the test substance 1-[(2,4-dimethylphenyl)diazenyl]-2-naphthol (CAS No: 3118-97-6).

 

The patch of 1-[(2,4-dimethylphenyl)diazenyl]-2-naphthol was applied onto the back of each patient for 24 hours by usingFinn Chambers® on Scanpor® (Epitest, Ltd. Oy). After removal of patch, skin reactions were assessedaccording to the ICDRG classification for 2 days.

 

Twenty-eight healthy female volunteers, aged 20 and 21, were also tested with the sample as controls. None gave a positive reaction to

 

Since thepositive reactions were seen in 2 out of total 8 cases,the test chemical1-[(2,4-dimethylphenyl)diazenyl]-2-naphthol (CAS No: 3118-97-6)was considered to be sensitizingin human patients suffering from pigmented contact dermatitis caused by the commercial Brilliant Lake Red R.