3-hydroxy-4-[(2-methoxy-5-nitrophenyl)azo]-N-(3-nitrophenyl)naphthalene-2-carboxamide

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Data is from experimental report

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1974

Report date:

1974

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: The procedure adopted was the patch-test technique described in the "Appraisal of the Safety of Chemicals in Foods, Drugs and Cosmetics" (1959) of the US Association of Food and Drug Officials (AFDO).

Principles of method if other than guideline:

The purpose of this test was to determine the primary-irritation index, which serves as a measure of the acute irritation, provoked by the compound Pigment Red 23 (CAS No: 6471-49-4)on the skin of the rabbits.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

3-hydroxy-4-[(2-methoxy-5-nitrophenyl)azo]-N-(3-nitrophenyl)naphthalene-2-carboxamide

EC Number:

229-313-2

EC Name:

3-hydroxy-4-[(2-methoxy-5-nitrophenyl)azo]-N-(3-nitrophenyl)naphthalene-2-carboxamide

Cas Number:

6471-49-4

Molecular formula:

C24H17N5O7

IUPAC Name:

3-hydroxy-4-[(2-methoxy-5-nitrophenyl)azo]-N-(3-nitrophenyl)naphthalene-2-carboxamide

Details on test material:

Name: Pigment Red 23
InChI:1S/C24H17N5O7/c1-36-21-10-9-17(29(34)35)13-20(21)26-27-22-18-8-3-2-5-14(18)11-19(23(22)30)24(31)25-15-6-4-7-16(12-15)28(32)33/h2-13,30H,1H3,(H,25,31)/b27-26+
Smiles: c12c(c(c(cc1cccc2)C(=O)Nc1cc(ccc1) [N+](=O)[O-])O)/N=N/c1c(ccc(c1)[N+](=O)[O-])OC
- Name of test material (as cited in study report):TK-11451
- Molecular formula (if other than submission substance):C24H17N5O7
- Molecular weight (if other than submission substance):213.2349 g/mol
- Substance type:Organic

Specific details on test material used for the study:

Name: Pigment Red 23
InChI:1S/C24H17N5O7/c1-36-21-10-9-17(29(34)35)13-20(21)26-27-22-18-8-3-2-5-14(18)11-19(23(22)30)24(31)25-15-6-4-7-16(12-15)28(32)33/h2-13,30H,1H3,(H,25,31)/b27-26+
Smiles: c12c(c(c(cc1cccc2)C(=O)Nc1cc(ccc1) [N+](=O)[O-])O)/N=N/c1c(ccc(c1)[N+](=O)[O-])OC
- Name of test material:TK-11451
- Molecular formula:C24H17N5O7
- Molecular weight:213.2349 g/mol
- Substance type: Organic

Test animals

Species:

rabbit

Strain:

other: Russian breed

Details on test animals or test system and environmental conditions:

- Weight at study initiation: 1.5 to 2 kgs
- Housing: In order to prevent injuries by bites the rabbits were kept separately in V2A wire cages
- Diet (e.g. ad libitum): (NAFAG, Gossau SG, rabbit food)
- Water (e.g. ad libitum): ad libitum

Test system

Type of coverage:

occlusive

Preparation of test site:

shaved

Remarks:

intact and scarified skin

Vehicle:

other: 50 % polyethylene glycol trituration (PEG 400)

Controls:

not specified

Amount / concentration applied:

500mg (0.5g)

Duration of treatment / exposure:

24 hours

Observation period:

24 and 72 hours

Number of animals:

6 (3/sex)

Details on study design:

- Area of exposure: whole back and flanks
- Type of wrap if used: The patch was covered with a plastic film 5 x 5 cm, which was fixed to the body with adhesive tape.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): no data
- Time after start of exposure: 24 hours

Results and discussion

In vivo

Results

Irritation parameter:

primary dermal irritation index (PDII)

Basis:

mean

Time point:

other: 24 and 72 hours

Score:

0

Max. score:

4

Reversibility:

not specified

Remarks on result:

no indication of irritation

Irritant / corrosive response data:

The primary irritation index as the measure of the acute skin irritation provoked by the substance was defined as the average of all the ratings found after 24 and 72 hours on the intact and slightly scarified skin. Compound producing combined averages (primary irritation indexes) of 2 or less were only mildly irritating; whereas those with indexes from 2 to 5 were moderate irritants, and those with scores above 6 were considered severe irritants.The primary irritation index of TK 11451/ Pigment Red 23 (CAS No: 6471-49-4) was 0.

Any other information on results incl. tables

Table 1: Evaluation of Skin Reactions

1.           Erythema and Eschar Formation               No erythema....................................................................................... 0               Very slight erythema (barely perceptible)............................................... 1               Well defined erythema......................................................................... 2               Moderate to severe erythema............................................................... 3               Severe erythema (beet redness) to slight               Eschar formation (injuries in depth)....................................................... 4               Maximum possible = 4

2.           edema Formation               No oedema......................................................................................... 0               Very slight edema (barely perceptible)................................................... 1               Slight edema (edges of area well defined by definite raising).................... 2               Moderate edema (raised approximately 1 mm........................................ 3               Severe edema (raised more than 1 mm and extending               Beyond area of exposure)......................................................................4                Maximum possible = 4

 

Applicant's summary and conclusion

Interpretation of results:

other: Not irritating

Conclusions:

The primary irritation index of chemical TK 11451/ Pigment Red 23 (CAS No: 6471-49-4) was estimated to be 0. Hence Pigment Red 23 (CAS No: 6471-49-4) was considered to be not irritating to the rabbits’ skin.

Executive summary:

The skin irritation study was conducted on six rabbits (3/sex) of Russian breed to determine the primary-irritation index, which serves as a measure of the acute irritation, provoked by the compound Pigment Red 23 (CAS No: 6471-49-4) on the skin of the rabbits.

 

In this test,each rabbits were shaved on the whole back and flanks two days before treatment with an electric clipper. The shaven skin on the left side was slightly scarified immediately before treatment. A gauze patch 2.5 x 2.5 cm was soaked with the test substance and immediately applied to the prepared skin.

 

The chemical was applied to the each side at a dose of 500 mg (0.5g) in 50 % polyethylene glycol trituration (PEG 400). The gauze patches were removed 24 hours after the application.

 

The reaction of the skin was appraised upon removal and after 72 hours.

 

The primary irritation index as the measure of the acute skin irritation provoked by the substance was defined as the average of all the ratings found after 24 and 72 hours on the intact and slightly scarified skin. Compound producing combined averages (primary irritation indexes) of 2 or less were only mildly irritating; whereas those with indexes from 2 to 5 were moderate irritants, and those with scores above 6 were considered severe irritants.

 

The primary irritation index of chemical TK 11451/ Pigment Red 23 (CAS No: 6471-49-4) was estimated to be 0. Hence Pigment Red 23 (CAS No: 6471-49-4) was considered to be not irritating to the rabbits’ skin.