Lithium bis[2-[(4,5-dihydro-3-methyl-5-oxo-1-phenyl-1H-pyrazol-4-yl)azo]benzoato(2-)]chromate(1-)

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 journals

Data source

Reference

Reference Type:

publication

Title:

Sensitization to azo dyes: negative patch tests to yellow and red azo dyes in printed paper

Author:

Thierbach MA, Geursen-Reitsma AM, van Joost T

Year:

1992

Bibliographic source:

Contact Dermatitis, 1992, 27, 22-26

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: Patch tests

Principles of method if other than guideline:

Patch tests were performed using C.I. Pigment Yellow 12 and other azo dyes to determine their sensitization potential on humans

GLP compliance:

not specified

Type of study:

patch test

Justification for non-LLNA method:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

2,2'-[(3,3'-dichloro[1,1'-biphenyl]-4,4'-diyl)bis(azo)]bis[3-oxo-N-phenylbutyramide]

EC Number:

228-787-8

EC Name:

2,2'-[(3,3'-dichloro[1,1'-biphenyl]-4,4'-diyl)bis(azo)]bis[3-oxo-N-phenylbutyramide]

Cas Number:

6358-85-6

Molecular formula:

C32H26Cl2N6O4

IUPAC Name:

2,2'-[(3,3'-dichlorobiphenyl-4,4'-diyl)didiazene-2,1-diyl]bis(3-oxo-N-phenylbutanamide)

Test material form:

solid: particulate/powder

Details on test material:

- Name of test material (as cited in study report): 2-{2-[2-chloro-4-(3-chloro-4-{2-[2-oxo-1-(phenylcarbamoyl)propyl]diazen-1-yl}phenyl)phenyl]diazen-1-yl}-3-oxo-N-phenylbutanamide
- Common name: C. I. Pigment Yellow 12
- Molecular formula: C32H26Cl2N6O4
- Molecular weight: 629.5014 g/mol
- Substance type: organic
- Physical state: solid

Specific details on test material used for the study:

Name of the chemical: 2-{2-[2-chloro-4-(3-chloro-4-{2-[2-oxo-1-(phenylcarbamoyl)propyl]diazen-1-yl}phenyl)phenyl]diazen-1-yl}-3-oxo-N-phenylbutanamide
Common Name: C.I. Pigment Yellow 12
Molecular Formula: C32H26Cl2N6O4
Molecular Weight: 629.5014 g/mol
SMILES Notation: CC(=O)C(/N=N/c1c(cc(cc1)c2cc(c(cc2)/N=N/C(C(=O)Nc3ccccc3)C(=O)C)Cl)Cl)C(=O)Nc4ccccc4
InChI: 1S/C32H26Cl2N6O4/c1-19(41)29(31(43)35-23-9-5-3-6-10-23)39-37-27-15-13-21(17-25(27)33)22-14-16-28(26(34)18-22)38-40-30(20(2)42)32(44)36-24-11-7-4-8-12-24/h3-18,29-30H,1-2H3,(H,35,43)(H,36,44)/b39-37+,40-38+
Substance Type: Organic
Physical State: Solid

In vivo test system

Test animals

Species:

other: humans

Strain:

not specified

Sex:

male/female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Department of Dermatology and Venereology, Academic Hospital, The Netherlands
- Age at study initiation: women – mean age = 39.9 years
Men- mean age = 46.6 years

Study design: in vivo (non-LLNA)

Induction

Route:

epicutaneous, occlusive

Vehicle:

other: white petrolatum

Concentration / amount:

2% in white petrolatum

Adequacy of induction:

other: Patients with well established p-aminoazobenzene allergy were selected for the patch tests

Challenge

No.:

#1

Route:

epicutaneous, occlusive

Vehicle:

other: white petrolatum

Concentration / amount:

2% in white petrolatum

Adequacy of challenge:

not specified

No. of animals per dose:

32 patients (20 women and 12 men)

Details on study design:

A group of 32 patients with p-aminoazobenzene allergy were presumed that an increase in color printed newspapers might cause dermatitis. Patch tests were performed using the azo dyes in the printed papers along with specimens of the colored-printed newspaper. The test group consisted for 20 women and 12 men. 30 patients with an allergic contact dermatitis but negative to p-aminoazobenzene and PPD were also tested with the same patch test series.
The dyes were kindly provided by the firms Hoechst and Ciba-Geigy. To avoid false-negative reactions, a test concentration of 2% in white petrolatum was chosen. Patch tests were performed using uniform patches and following Standard procedures.

Challenge controls:

30 patients with an allergic contact dermatitis but negative to p-aminoazobenzene and PPD[para-phenylenediamine] were also tested with the same patch test series

Positive control substance(s):

not specified

Results and discussion

In vivo (non-LLNA)

Results

Reading:

1st reading

Group:

test chemical

Dose level:

2% in white petrolatum

No. with + reactions:

0

Total no. in group:

32

Clinical observations:

C.I. Pigment Yellow 12 did not elicit a positive patch test reaction in any of the 32 patients positive to p-aminoazobenzene, nor in the 30 control volunteers

Remarks on result:

no indication of skin sensitisation

Applicant's summary and conclusion

Interpretation of results:

other: not sensitizing

Conclusions:

C.I. Pigment Yellow 12 did not elicit a positive patch test reaction in any of the 32 patients positive to p-aminoazobenzene, nor in the 30 control volunteers
Hence, C.I Pigment Yellow 12 can be considered to be not sensitizing to skin.

Executive summary:

A group of 32 patients with p-aminoazobenzene allergy were presumed that an increase in color printed newspapers might cause dermatitis. Patch tests were performed using the azo dyes in the printed papers along with specimens of the colored-printed newspaper. The test group consisted for 20 women and 12 men. 30 patients with an allergic contact dermatitis but negative to p-aminoazobenzene and PPD were also tested with the same patch test series.

The dyes were kindly provided by the firms Hoechst and Ciba-Geigy. To avoid false-negative reactions, a test concentration of 2% in white petrolatum was chosen. Patch tests were performed using uniform patches and following Standard procedures.

C.I. Pigment Yellow 12 did not elicit a positive patch test reaction in any of the 32 patients positive to p-aminoazobenzene, nor in the 30 control volunteers

Hence, C.I Pigment Yellow 12 can be considered to be not sensitizing to skin.