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Diss Factsheets

Toxicological information

Skin irritation / corrosion

Currently viewing:

Administrative data

Endpoint:
skin irritation: in vivo
Type of information:
experimental study
Adequacy of study:
weight of evidence
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 on the skin of the rabbits.
GLP compliance:
not specified

Test material

Constituent 1
Chemical structure
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-[(E)-2-(2-methoxy-5-nitrophenyl)diazen-1-yl]-N-(3-nitrophenyl)naphthalene-2-carboxamide
Test material form:
solid: particulate/powder
Details on test material:
IUPAC Name: 3-hydroxy-4-[(2-methoxy-5-nitrophenyl)azo]-N-(3-nitrophenyl)naphthalene-2-carboxamid
Common 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:C24H17N5O7
Molecular weight: 213.2349 g/mol
Substance type:Organic
Physical State: Solid

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 2: Evaluation of Skin Reactions

Animal no.

Sex

Skin reactions

24 hours after application

72 hours after application

Intact skin

Scarified skin

Intact skin

Scarified skin

1 (male)

Erythema

0

0

0

0

Edema

0

0

0

0

2 (male)

Erythema

0

0

0

0

Edema

0

0

0

0

3 (male)

Erythema

0

0

0

0

Edema

0

0

0

0

4 (female)

Erythema

0

0

0

0

Edema

0

0

0

0

5 (female)

Erythema

0

0

0

0

Edema

0

0

0

0

6 (female)

Erythema

0

0

0

0

Edema

0

0

0

0

Applicant's summary and conclusion

Interpretation of results:
other: Not irritating
Conclusions:
The primary irritation index of chemical was estimated to be 0. Hence, the test chemical was considered to be not irritating to the rabbits’ skin.
 
Executive summary:

The skin irritation study was conducted to determine the primary-irritation index, which serves as a measure of the acute irritation, provoked by the compound on the skin of the rabbits.

The study was performed as per 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).Six rabbits (3/sex) of Russian breed were used for the study.

 

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 was estimated to be 0. Hence, the test chemical was considered to be not irritating to the rabbits’ skin.