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Toxicological information

Skin irritation / corrosion

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Administrative data

Endpoint:
skin irritation / corrosion, other
Remarks:
Skin irritation, in vivo
Type of information:
experimental study
Adequacy of study:
key study
Study period:
Oct. 12-27, 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:
1995

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 404 (Acute Dermal Irritation / Corrosion)
Version / remarks:
1992
Deviations:
no
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Type:
Constituent
Type:
Constituent
Type:
Constituent
Test material form:
liquid
Details on test material:
- Substance type: UVCB
- Physical state: Liquid
- Lot/batch No.: PPA 4852
- Expiration date of the lot/batch: No specific expiration date. At least 10 years or as long as enzyme activity is preserved
- Stability under test conditions: Solutions in water are stable for at least 24 hours at room temperature or 4 degrees Celcius
- Storage condition of test material: minus 18 degrees of C

Test animals

Species:
rabbit
Strain:
New Zealand White
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Bred by Charles River, UK
- Weight at study initiation: between 2.45 - 2.65 kg
- Age at study initiation: Young adults, approx. 3 months
- Housing: Individually, in animal room with control of temperature (15-23C) and humidity (40-70%RH)
- Diet (e.g. ad libitum): Standard diet ad libitum
- Water (e.g. ad libitum): Automatic, ad libitum
- Acclimation period: 7 days
- Photoperiod (hrs dark / hrs light): 12 hrs/12hrs

IN-LIFE DATES: From: 1994-10-12 To: 1994-10-27

Test system

Type of coverage:
semiocclusive
Preparation of test site:
shaved
Vehicle:
water
Controls:
not required
Amount / concentration applied:
0.5 mL of the test material diluted to retail activity (445 mg test material made up to 1000 mg with water), corresponding to a solution with 4.5% active enzyme protein
Duration of treatment / exposure:
4 hours
Observation period:
16 days
Number of animals:
3
Details on study design:
The test compound Subtilisin was assessed by semiocclusive application of 0.5 mL of the test material formulation to the closely-clipped dorsa of three New Zealand White rabbits for 4 hrs.
The study was conducted to comply with the following guidelines:
- Organisation for Economic Co-operation and Development (OECD) test guideline 404.

Results and discussion

In vivo

Resultsopen allclose all
Irritation parameter:
erythema score
Basis:
animal #1
Time point:
other: Mean of 24, 48, 72 h
Score:
1.3
Max. score:
2
Reversibility:
fully reversible
Remarks on result:
other: Very slight exfoliation was evident until termination of the study (day16) in the present animal.
Irritation parameter:
edema score
Basis:
animal #1
Time point:
other: Mean 24, 48, 72 h
Score:
1
Max. score:
1
Reversibility:
fully reversible
Irritation parameter:
erythema score
Basis:
animal #2
Time point:
other: Mean 24, 48, 72 h
Score:
0
Max. score:
0
Reversibility:
fully reversible
Irritation parameter:
edema score
Basis:
animal #2
Time point:
other: Mean 24, 48, 72 h
Score:
0
Max. score:
0
Reversibility:
fully reversible
Irritation parameter:
erythema score
Basis:
animal #3
Time point:
other: Mean 24, 48, 72 h
Score:
1.3
Max. score:
2
Reversibility:
fully reversible
Remarks on result:
other: Exfoliation was seen until day 13 in this animal, all other effects were cleared at day 10.
Irritation parameter:
edema score
Basis:
animal #3
Time point:
other: Mean 24, 48, 72 h
Score:
2.3
Max. score:
3
Reversibility:
fully reversible
Irritant / corrosive response data:
Very slight or well defined erythema and very slight to moderate oedema were observed at the test sites of two animals during the first 72 hrs after bandage removal. One of these animals also showed a dry abrasion over the majority of the test site during this time. One week after treatment, very slight erythema and exfoliation were evident in both animals. The exfoliation persisted until day 13 in one animal and to termination of the study in the other. No dermal response was observed at the tests site of the third animal at any time during the observation period.
The mean values for erythema and oedema recorded 24, 48 and 72 hours after treatment did not exceed the limit values considered to indicate a significant inflammatory response.

Applicant's summary and conclusion

Interpretation of results:
Category 3 (mild irritant) based on GHS criteria
Conclusions:
According to EC-standards (as published in the Official Journal of the European Communities, L 110 A, 4 May 1993), the test material is not irritating to skin. Concentration of solution applied was 4.5% expressed as active enzyme protein.
Executive summary:

An in vivo skin irritation test was conducted to assess the potential of the test substance, Subtilisin, batch PPA 4852, to cause skin irritation. The OECD test guideline 404 was followed. 0.5 mL of the test material formulation was applied under semiocclusive conditions to the closely-clipped dorsa of three New Zealand White rabbits for 4 hrs. The study was conducted in accordance with GLP. The study concluded that the test substance, Subtilisin, was non-irritant to the skin.

However due to the very slight exfoliation still seen in one animal at the termination of the study, Subtilisin should be regarded as slightly irritant to skin.