[No public or meaningful name is available]

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

13/01/1999 to 02/02/1999

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1999

Report date:

1999

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Test material form:

liquid

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: David Percival Ltd., Cheshire, UK.
- Age at study initiation: 12-16 weeks.
- Weight at study initiation: 2.77-3.17 kg.
- Housing: Individually housed in suspended metal cages.
- Diet (e.g. ad libitum): Ad libitum
- Water (e.g. ad libitum): Ad libitum
- Acclimation period: At least five days.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 17-21
- Humidity (%): 44-70
- Air changes (per hr): Approximately 15.
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: No data

Test system

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

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

Duration of treatment / exposure:

4 hours

Observation period:

14 days

Number of animals:

Three

Details on study design:

TEST SITE
- Area of exposure: Three suitable test sites selected on the backs of the rabbits. A 2.5 x 2.5 cm cotton gauze was used.
- % coverage: No data
- Type of wrap if used: Patch was secured with a strip of surgical adhesive tape and covered with an elasticated corset.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): Residual test substance was removed by gentle swabbing with cotton wool soaked in 74% Industrial Methylated spirits.
- Time after start of exposure: 4 hours.

SCORING SYSTEM: Draize, 1977

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible

Remarks:

erythema

Remarks on result:

other: Reduced fur growth at 14 days.

Results 2

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible

Remarks:

erythema

Remarks on result:

other: Reduced fur growth and mild desquamation at 14 days.

Results 3

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible

Remarks:

erythema

Remarks on result:

other: Reduced fur growth and mild desquamation at 14 days.

Results 4

Irritation parameter:

edema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible

Remarks:

edema

Results 5

Irritation parameter:

edema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

2.33

Max. score:

4

Reversibility:

fully reversible

Remarks:

edema

Results 6

Irritation parameter:

edema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible

Remarks:

edema

Irritant / corrosive response data:

Loss of skin flexibility and/or loss of skin elasticity were noted at all of the treated skin sites at the 72-hour observation. Crust formation, which precluded the evaluation of erythema and oedema, was noted at all of the treated sites at the 7-day observation. Slight desquamation or reduced regrowth of fur were noted at all of the treated skin sites at the 14-day observation.

Other effects:

At 7 days following exposure the erythema and oedema could not be assessed due to 'crust formation'. At 14 days erythema and oedema had reversed but there was reduced fur growth in 3/3 animals and mild desquamation in 2/3 animals.

Any other information on results incl. tables

Table 1 Skin irritation results

   

Skin reaction	Reading (hours)	Individual scores
		Male 1	Male 2	Female
	24	2	2	2
Erythema/eschar formation	48	2	2	2
	72	2	2	2
Total		6	6	6
Mean score		2.0	2.0	2.0
	24	2	3	2
Oedema	48	2	2	2
	72	2	2	2
Total		6	7	6
Mean score		2.0	2.3	2.0

                                           

Applicant's summary and conclusion

Interpretation of results:

Category 2 (irritant)

Conclusions:

Based on a skin irritation study conducted to OECD 404 and in compliance with GLP, the test substance was irritating to the skin of rabbits. Erythema were observed in all three animals tested, with mean 24-72 hour scores of 2 in all three animals tested. For oedema the mean 24-72 hour score was 2 in 2/3 animals and 2.3 in 1/3 animals tested. At 7 days following exposure the erythema and oedema could not be assessed due to 'crust formation'. At 14 days erythema and oedema had reversed but there was reduced fur growth in 3/3 animals and mild desquamation in 2/3 animals. Therefore due to the reduced fur growth and desquamation at the end of the observation period (14 days), the test substance is concluded to be irritating to skin.