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Toxicological information

Skin irritation / corrosion

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Administrative data

Endpoint:
skin irritation: in vivo
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Non GLP, guideline study, available as unpublished report, no restrictions, fully adequate for assessment.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1981
Report Date:
1981

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
other: Code of Federal Regulations, Title 16, Section 1500.41
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 404 (Acute Dermal Irritation / Corrosion)
GLP compliance:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): Metanilic acid wet

Test animals

Species:
rabbit
Strain:
New Zealand White
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: der Lippischen Versuchstierzucht, Extertal, Germany
- Weight at study initiation: average 2.1 kg
- Housing: The animals were kept in individual cages
- Diet (e.g. ad libitum): animals received "Mümmel z" (SSNIF, Soest, Germany) ad libitum.
- Water (e.g. ad libitum): water ad libitum
- Acclimation period: 7 - 14 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 16 - 18
- Humidity (%): 40
- Photoperiod (hrs dark / hrs light): 12h light- / 12h dark cycle

Test system

Type of coverage:
occlusive
Preparation of test site:
other: Left flanks: clipped. Right flanks: abraded
Vehicle:
water
Controls:
not specified
Amount / concentration applied:
500 mg of the test substance suspended with water
Duration of treatment / exposure:
24 hour
Observation period:
8 days
Number of animals:
6
Details on study design:
Test Procedure:
Hair was removed from a skin area of about 8 x 8 cm of the right and left flanks of 6 rabbits with an average weight of 2.1 kg using electric clippers 24 hours before the beginning of the test. In addition, the skin of the right flank was abraded at the site of application for the test patch by means of a scarificator. Test patches of 2.5 x 2.5 cm consisting of double layers of surgical gauze were coated with/soaked in 500 mg of the test substance suspended with water and covered with an indifferent, impermeable PVC foil (5 x 5 cm). The foil with the test patches underneath was fixed onto the two test sites by means of nonirritant adhesive tape (Leukoflex®). Subsequently, the total trunk of the animals was bandaged using an elastic bandage (EioflexR) for the total exposure period of 24 hours. The animals were immobilized.

Examinations:
The findings were recorded immediately (about 30 min) after removal of the patches (24-hour value) and then 48 hours and 72 hours after the beginning of the test (48 hours after the first reading). The 48-hour value was not included in the report sheet. The control finding obtained after 8 days was not included in the assessment of the irritation index.

Evaluation:
The findings were assessed according to the following scale and afterward the irritation index (index of primary irritation) was determined.

Scoring system:
1. 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); 4

2. Edema Formation
No edema; 0
Very slight, barely perceptible edema; 1
Slight oedema (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 exposure); 4

The values for erythema and edema obtained on the intact and abraded skin of each test animal after 24 and 72 hours are added and the means are determined from these. The 8 means determined in this way are divided by 4 to give the primary irritation index to the skin.

Classification:
0.0 to 0.5 non-irritating
0.6 to 3.0 slightly irritating
3.1 to 5.0 moderately irritating
5.1 to 8.0 severely irritating

Results and discussion

In vivo

Resultsopen allclose all
Irritation parameter:
erythema score
Basis:
mean
Time point:
other: 24 hours
Score:
1.83
Max. score:
4
Reversibility:
not fully reversible within: 8 days
Remarks on result:
other: intact skin
Irritation parameter:
erythema score
Basis:
mean
Time point:
other: 72 hours
Score:
1.17
Max. score:
4
Reversibility:
not fully reversible within: 8 days
Remarks on result:
other: intact skin
Irritation parameter:
erythema score
Basis:
mean
Time point:
other: 8 days
Score:
1
Max. score:
4
Remarks on result:
other: intact skin
Irritation parameter:
erythema score
Basis:
mean
Time point:
other: 24 hours
Score:
2.17
Max. score:
4
Reversibility:
not fully reversible within: 8 days
Remarks on result:
other: abraded skin
Irritation parameter:
erythema score
Basis:
mean
Time point:
other: 72 hours
Score:
1
Max. score:
4
Reversibility:
not fully reversible within: 8 days
Remarks on result:
other: abraded skin
Irritation parameter:
erythema score
Basis:
mean
Time point:
other: 8 days
Score:
0.67
Max. score:
4
Remarks on result:
other: abraded skin
Irritation parameter:
edema score
Basis:
mean
Time point:
other: 24 hours
Score:
0.5
Max. score:
4
Reversibility:
fully reversible within: 48 hours
Remarks on result:
other: intact skin
Irritation parameter:
edema score
Basis:
mean
Time point:
other: 72 hours - 8 days
Score:
0
Max. score:
4
Remarks on result:
other: intact sking
Irritation parameter:
edema score
Basis:
mean
Time point:
other: 24 hours
Score:
0.33
Max. score:
4
Reversibility:
fully reversible within: 48 hours
Remarks on result:
other: abraded skin
Irritation parameter:
edema score
Basis:
mean
Time point:
other: 72 hours - 8 days
Score:
0
Max. score:
4
Remarks on result:
other: abraded skin
Irritation parameter:
primary dermal irritation index (PDII)
Basis:
mean
Time point:
other: 24 - 72 hours
Score:
1.8
Max. score:
8
Irritant / corrosive response data:
Still weak erythema after 8 days.

Applicant's summary and conclusion

Interpretation of results:
slightly irritating
Remarks:
Migrated information Criteria used for interpretation of results: EU