2-(1,3-dihydro-3-oxo-2H-indol-2-ylidene)-1,2-dihydro-3H-indol-3-one

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1979

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: No GLP study; Comparable to guideline study; limited information on test itemand its formulation and animal husbandry. Test are in concordance with those recommended by the ETAD. The study results are considered valid for indigo.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1979

Report date:

1979

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

other: FDA Federal Register 38, No 187

Principles of method if other than guideline:

Patch test technique on abraded and intact skin

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

2-(1,3-dihydro-3-oxo-2H-indol-2-ylidene)-1,2-dihydro-3H-indol-3-one

EC Number:

207-586-9

EC Name:

2-(1,3-dihydro-3-oxo-2H-indol-2-ylidene)-1,2-dihydro-3H-indol-3-one

Cas Number:

482-89-3

Molecular formula:

C16H10N2O2

IUPAC Name:

2-(1,3-dihydro-3-oxo-2H-indol-2-ylidene)-1,2-dihydro-3H-indol-3-one

Details on test material:

- Name of test material (as cited in study report): Indigo-N-Lumps
- Substance type: active ingredient
- Physical state: solid

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

single housed

Test system

Type of coverage:

occlusive

Preparation of test site:

other: shaved and abraded

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

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

Duration of treatment / exposure:

24 hours

Observation period:

immediately after removal (24 hours after application) and 48 hours after removal (72 hours after application)

Number of animals:

6

Details on study design:

TEST SITE
- Area of exposure: back
- Coverage: - shaved and scarified skin: 2.5x2.5 cm
- shaved skin: 2.5x2.5 cm
- Type of wrap if used: rubber sheeting


REMOVAL OF TEST SUBSTANCE
- Time after start of exposure: 24 hours with cotton wool and warm water


SCORING SYSTEM: FDA Federal Register 38, No 187

Erythema and eschar formation (EEF) :
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

Edema formation (EF):
No edema 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 exp.) 4

Calculation of Primary Irritation Indey for intact and abraded skin.
Mean value of 6 animals

Primary Irritation Index (PII) = Animal 1 (EEF24h-abraded + EEF72h-abraded + EEF24h-shaved + EEF72h-shaved + EF24h-abraded + EF72h-abraded + EF24h-shaved + EF72h-shaved) + .... + Animal 6 (EEF24h-abraded + EEF72h-abraded + EEF24h-shaved + EEF72h-shaved + EF24h-abraded + EF72h-abraded + EF24h-shaved + EF72h-shaved)/ 24

EVALUATION:

0.0 - 0.5 non-irritant
0.6 - 3.0 slightly irritant
3.1 - 5.0 moderately irritant
5.1 - 8.0 severely irritant

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:

8

Irritant / corrosive response data:

not irritant

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: US CPSC / US FDA

Conclusions:

The application of Indigo N Lumps to intact and abraded skin for 24 hours did not lead to any signs of skin irritation