NITTA

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

29 April 1987 to 6 May 1987

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1987

Report date:

1987

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Test material form:

liquid: viscous

Details on test material:

- Appearance: amber-coloured, slightly viscous liquid
- Storage conditions: room temperature

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Nottingham University, School of Agriculture, Sutton Bonington, Leicestershire, UK and David Percival Ltd., Moston, Sandbach, Cheshire, UK
- Age at study initiation: ca. 12 - 16 weeks
- Weight at study initiation: 2.40 - 3.12 kg
- Housing: Animals were housed individually in suspended metal cages
- Diet: ad libitum (Rabbit Diet, Preston Farmers Ltd., New Leake, Lincolnshire)
- Water: ad libitum
- Acclimation period: 5 days (minimum)

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 17 - 21 °C
- Humidity (%): 50 - 60 %
- Air changes (per hr): ca. 15 air changes per hour
- Photoperiod (hrs dark / hrs light): 12 hours dark / 12 hours light

Test system

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

unchanged (no vehicle)

Amount / concentration applied:

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

Duration of treatment / exposure:

4 h

Observation period:

72 hours

Number of animals:

3

Details on study design:

TEST SITE
- Area of exposure: ca. 24 hours before treatment, the dorsal/flank fur was clipped free of fur
- Coverage: each animals was treated by dermal application of 0.5 mL of test material
- Type of wrap if used: the test material was covered with a gauze patch of 2.5 x 2.5 cm. The patch was secured with surgical tape.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): four hours after application, the dressing was removed and the skin cleaned by gentle swabbing with cotton wool soaked in diethyl ether.

SCORING SYSTEM: skin reaction were scored using the Draize scoring system 1, 24, 48 and 72 hours after removal of test material.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal #1

Remarks:

(mean score 1)

Time point:

other: overall at 24, 48 and 72 h

Score:

0.3

Max. score:

1

Reversibility:

fully reversible within: 48 hours

Results 2

Irritation parameter:

erythema score

Basis:

animal #2

Remarks:

(mean score 2)

Time point:

other: overall at 24, 48 and 72 h

Score:

1

Max. score:

1

Reversibility:

fully reversible within: 7 days

Results 3

Irritation parameter:

erythema score

Basis:

animal #3

Remarks:

(mean score 3)

Time point:

other: overall at 24, 48 and 72 h

Score:

1

Max. score:

1

Reversibility:

fully reversible within: 7 days

Results 4

Irritation parameter:

edema score

Basis:

animal #1

Remarks:

(mean score 1)

Time point:

other: overall at 24, 48 and 72 h

Score:

0

Max. score:

0

Results 5

Irritation parameter:

edema score

Basis:

animal #2

Remarks:

(mean score 2)

Time point:

other: overall at 24, 48 and 72 h

Score:

0.3

Max. score:

1

Reversibility:

fully reversible within: 48 hours

Results 6

Irritation parameter:

edema score

Basis:

animal #3

Remarks:

(mean score 3)

Time point:

other: overall at 24, 48 and 72 h

Score:

0

Max. score:

0

Irritant / corrosive response data:

Very slight erythema was noted at one treated skin site one hour after removal of the patches. Very slight erythema with or without oedema was noted at all treated skin sites at the 24-hour observation and at two treated skin sites at the 48 and 72-hour observations. Desquamation was also noted at one of these treated skin sites at the 72-hour observation. Desquamation only was apparent at two treated skin sites seven days after treatment.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Under the conditions of the study the test material was found not to be a skin irritant.

Executive summary:

The potential of the test material to cause skin irritation was investigated in a study which was conducted under GLP conditions and in accordance with the standardised guideline OECD 404.

During the study three rabbits were exposed to 0.5 mL test material onto clipped skin for 4 hours using a semi-occulsive dressing. Skin reactions were assessed 1, 24, 48 amd 72 hours after exposure.

Exposure to the test material resulted in very slight erythema at one treated skin site one hour after removal of the patches. Very slight erythema with or without oedema was noted at all treated skin sites at the 24-hour observation and at two treated skin sites at the 48 and 72-hour observations. Desquamation was also noted at one of these treated skin sites at the 72-hour observation. Desquamation only was apparent at two treated skin sites seven days after treatment.

Based on these results, the test material was concluded not to be a skin irritant.