2-[(4-chloro-2-nitrophenyl)azo]-N-(2,3-dihydro-2-oxo-1H-benzimidazol-5-yl)-3-oxobutyramide

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 14 MAR 1977 to 17 MAR 1977

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: FDA guideline (minor deviations from OECD guideline)

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1977

Report date:

1977

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: FDA guideline (Federal register 38, No. 187, 27.9.1973, p.27019)

Deviations:

no

GLP compliance:

no

Remarks:

study was performed previous to GLP implementation

Test material

Test material information

Constituent 1

Reference substance name:

2-[(4-chloro-2-nitrophenyl)azo]-N-(2,3-dihydro-2-oxo-1H-benzimidazol-5-yl)-3-oxobutyramide

EC Number:

235-462-4

EC Name:

2-[(4-chloro-2-nitrophenyl)azo]-N-(2,3-dihydro-2-oxo-1H-benzimidazol-5-yl)-3-oxobutyramide

Cas Number:

12236-62-3

Molecular formula:

C17H13ClN6O5

IUPAC Name:

2-[(4-chloro-2-nitrophenyl)diazenyl]-3-oxo-N-(2-oxo-2,3-dihydro-1H-benzimidazol-5-yl)butanamide

Test material form:

solid: bulk

Test animals

Species:

rabbit

Strain:

other: New Zealand

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Weight at study initiation: 1.5 - 2.0 kg
- Housing: single
- Diet: ERKA 8300 (Futtermittelwerke Robert Koch oHG, Hamm, Germany), ad libitum
- Water: ad libitum

Test system

Type of coverage:

occlusive

Preparation of test site:

other: clipped/intact or clipped/scarified

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 500 mg

Duration of treatment / exposure:

24 h (i.e. removal of the patch 24 h after start of treatment)

Observation period:

start of treatment: 0 h (zero hour)
end of treatment: removal of the patch 24 h after start of treatment
first reading: 24 h after start of treatment (= 0 h after end of treatment)
second reading: 48 h after start of treatment (= 24 after end of treatment)
third reading: 72 h after start of treament (= 48 h after end of treatment)

Number of animals:

6

Details on study design:

TEST SITE
- Area of exposure: 2.5 x 2.5 cm
- Type of wrap if used: gauze patch

REMOVAL OF TEST SUBSTANCE
- Washing (if done): no

SCORING SYSTEM: erythema and edema scores (0-4)

Skin was evaluated immediately, 24 h and 48 h after removal of the patch. Mean values for readings were calculated for each animal.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

mean

Time point:

other: 24 and 48 h after end of treatment

Score:

0

Max. score:

4

Reversibility:

other: not relevant since no effect

Results 2

Irritation parameter:

edema score

Basis:

mean

Time point:

other: 24 and 48 h after end of treatment

Score:

0

Max. score:

4

Reversibility:

other: not relevant since no effect

Irritant / corrosive response data:

Immediately after removal of patch no erythema score could be determined due to pigment overlay. Edema score at this time point was 0 for all animals. No edema or eryhthema were seen 24 and 48 h after removal of the patch (score 0).
Results on scarified skin showed identical results.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Remarks:

Regulation (EC) no 1272/2008

Conclusions:

The test material is not irritating to skin under these test conditions.
This conclusion is legitimate even though the applied testing regime differs from today's standard methods. Since the test conditions were more stringent than required by OECD TG 404 (i.e. 24 h treatment, occlusive coverage, and scarified skin instead of 4 h treatment, semi-occlusive coverage, and intact skin) the test results are considered adequate to fulfill the endpoint requirements.

Executive summary:

The test material was tested for skin irritancy according to FDA guidelines. Both intact and scarified skin sites of six rabbits were exposed to 0.5 g test substance for 24 h under occlusive conditions and the skin responses were observed for 48 hours after end of exposure. Immediately after removal of patch no erythema score could be determined due to pigment overlay. No erythema were seen at the later observation time points. No edema were seen at any time point (score 0). The test item is not irritating under these test conditions.