Benzenesulfonic acid, 4-chloro-2-[2-[4,5-dihydro-3-methyl-5-oxo-1-(3-sulfophenyl)-1H-pyrazol-4-yl]diazenyl]-5-methyl-, ammonium salt (1:2)

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

May - June 1994

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1994

Report date:

1994

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

EU Method B.4 (Acute Toxicity: Dermal Irritation / Corrosion)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Test material form:

solid: particulate/powder

Details on test material:

- Appearance: Yellow powder

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Lot/batch number of test material: KL384
- Expiration date of the lot/batch: not specified
- Purity test date: not specified


STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: room temperature in the dark
- Stability under storage conditions: not specified
- Stability under test conditions: not specified
- Solubility and stability of the test substance in the solvent/dispersant/vehicle/test medium: not applicable

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: no

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Froxfield (U.K.) Ltd., Petersfield, Hampshire, England
- Age at study initiation: approximately 13 to 14 weeks
- Weight at study initiation: 3.0 to 3.2 kg
- Housing: one animal per cage
- Diet: standard laboratory diet SDS Stanrab (P) Rabbit Diet ad libitum
- Water: drinking water ad libitum
- Acclimation period: yes; duration not specified
- Microbiological status when known: not specified
- Method of randomisation in assigning animals to test and control groups: not specified

ENVIRONMENTAL CONDITIONS
- Temperature (°C): approximately 19°C
- Humidity (%): 30 - 70
- Air changes (per hr): approximately 19
- Photoperiod (hrs dark / hrs light): 12 / 12

IN-LIFE DATES: From: To: not specified

Test system

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

water

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 g

VEHICLE
- Amount(s) applied (volume or weight with unit): A 0.5 g amount of the test substance was applied under a 25 mm x 25 mn gauze pad which had been moistened with 0.5 ml distilled water to one intact skin site on each animal.

Duration of treatment / exposure:

4h

Observation period:

4d

Number of animals:

3 females

Details on study design:

TEST SITE
- Area of exposure: dorso-lumbar region
- % coverage: not specified
- Type of wrap if used: gauze pad and "Elastoplast" elastic adhesive dressing

REMOVAL OF TEST SUBSTANCE
- Washing (if done): At the end of the exposure period, the semi-occlusive dressing and gauze pad were removed and the treatment site was washed with warm water (30° to 40°C) to remove any residual test substance. The
treated area was blotted dry with absorbent paper.
- Time after start of exposure: 4h

OBSERVATION TIME POINTS
- Examination of the treated skin was made on Day 1 (i.e. approximately 60 minutes after removal of the dressings) and on Days 2, 3 and 4 (equivalent to 24, 48 and 72 hours after exposure).

SCORING SYSTEM:
Local dermal irritation was assessed using the prescribed numerical system:
- 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)
preventing erythema reading - 4
- Oedema formation:
No oedema - 0
Very slight oedema (barely perceptible) - 1
Slight oedema (edges of area well-defined by definite raising) - 2
Moderate oedema (raised approximately 1 millimetre) - 3
Severe oedema (raised more than 1 millimetre and extending
beyond the area of exposure) - 4
Any other lesion not covered by this scoring system, was described.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

mean

Remarks:

mean of all 3 animals

Time point:

other: approx. 60 minutes after removal of the dressing

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 24 h

Results 2

Irritation parameter:

erythema score

Basis:

mean

Remarks:

mean of all 3 animals

Time point:

24/48/72 h

Score:

0

Max. score:

4

Results 3

Irritation parameter:

edema score

Basis:

animal #1

Time point:

other: approx. 60 minutes after removal of the dressing

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 24 h

Results 4

Irritation parameter:

edema score

Basis:

animal #2

Time point:

other: approx. 60 minutes after removal of the dressing

Score:

0

Max. score:

4

Results 5

Irritation parameter:

edema score

Basis:

animal #3

Time point:

other: 60 minutes after removal of the dressing

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 24 h

Results 6

Irritation parameter:

edema score

Basis:

mean

Remarks:

mean of all 3 animals

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritant / corrosive response data:

Very slight erythema with or without very slight oedema was seen in all three animals on Day 1 only (score 1). All reactions has resolved by day 2.

Other effects:

There were no signs of toxicity or ill health in any rabbit during the observation period.

Any other information on results incl. tables

Tab. 1: Dermal reactions observed after application of the test substance

Rabbit number	E=Erythema 0=Oedema	Day
		1*	2	3	4
556	E 0	1 1	0 0	0 0	0 0
557	E 0	1 0	0 0	0 0	0 0
558	E 0	1 1	0 0	0 0	0 0

* Approximately 60 minutes after removal of the dressing

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

A single semi-occlusive application of the test substance to intact rabbit skin for four hours elicited transient very slight dermal reactions which were fully reversible within 24 hours.

Executive summary:

A study was performed to assess the skin irritation potential of the test substance to the rabbit.

The method followed was that described in EEC Methods for the determination of toxicity, Annex to Directive 92/69/EEC (OJ No. L383A, 29.12.92), Part B, Mediod B.4. Acute toxicity (skin irritation). The study was performed under GLP conditions.

Three rabbits were each administered a single dermal dose of 0.5 g of the test substance and observed for four days.

A single semi-occlusive application of the test substance to intact rabbit skin for four hours elicited transient very slight dermal reactions. All reactions had resolved by Day 2.