Registration Dossier

Administrative data

Endpoint:
skin irritation: in vivo
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1988
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Well performed GLP and OECD guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1988
Report Date:
1988

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 404 (Acute Dermal Irritation / Corrosion)
Qualifier:
according to
Guideline:
EU Method B.4 (Acute Toxicity: Dermal Irritation / Corrosion)
Version / remarks:
84/449/EEC
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent

Test animals

Species:
rabbit
Strain:
New Zealand White
Details on test animals and environmental conditions:
- Animal specifics: Hoechst AG, conventional breed
- Source: Hoechst AG breeding colony
- Age at study initiation: 3 months to 5 months
- Weight at study initiation: 1,9 kg to 2,5 kg
- Housing: Individually in stainless steel cages equipped with feed hoppers and drinking water bowls
- Diet (e.g. ad libitum): standard laboratory diet (Albtromin 2123) ad libitum, appr. 15 g hay daily
- Water (e.g. ad libitum): deionized chlorinated water, ad libitum

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20° ± 3°C (air-condition)
- Humidity (%): 30-70%
- Photoperiod (hrs dark / hrs light): 12/12

Test system

Type of coverage:
semiocclusive
Preparation of test site:
shaved
Vehicle:
other: Polyethyleneglycol 400
Controls:
not required
Amount / concentration applied:
TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 g mixed with 0.3 mL Polyethyleneglycol 400

VEHICLE
- Amount(s) applied (volume or weight with unit):1.0 ml to moisten the test item
- Lot/batch no. (if required): Ch-B 2322 , Riedel de Haen AG
Duration of treatment / exposure:
4 hours
at the end of the exposure period removal of test substance by washing with lukewarm tap water
Observation period:
72 h post removal of the patch
Number of animals:
3
Details on study design:
TEST SITE
- Area of exposure: approximately 2.5 cm x 2.5 cm
- Type of wrap if used: surgical gauze patch (Beiersdorf AG)

REMOVAL OF TEST SUBSTANCE
- Washing (if done): flushed with lukewarm tap water
- Time after start of exposure: 4 hours

SCORING SYSTEM:
as in EU Method B.4, assessed approximately 30 - 60 min, 24, 48, and 72 h after the romoval of the test item

Results and discussion

In vivo

Resultsopen allclose all
Irritation parameter:
erythema score
Basis:
animal: # 1, 2, 3 each
Time point:
other: mean of 24, 48 and 72 hours
Score:
0.1
Max. score:
4
Reversibility:
other: slight signs of irritation (erythema) observed in one animal at 24 h reading was fully reversible within 48 hours
Irritation parameter:
edema score
Basis:
animal: # 1, 2, 3 each
Time point:
other: mean of 24, 48 and 72 hours
Score:
0
Max. score:
4
Reversibility:
other: no signs of irritation (edema) at any time
Irritant / corrosive response data:
Scores (oedema or erythema) were 0 at 48 and 72 h after removal of dressing in all animals (see table below for individual data).
Other effects:
No other effects reported

Any other information on results incl. tables

Table 1: individual scores

Animal no

Evaluation interval after removal of dressing

Erythema score

Edema score

1

 

30 – 60 min

0

0

2

0

0

3

0

0

1

 

24 h

0

0

2

0

0

3

1

0

1

 

48 h

0

0

2

0

0

3

0

0

1

 

72 h

0

0

2

0

0

3

0

0

Applicant's summary and conclusion

Interpretation of results:
not irritating
Remarks:
Migrated information Criteria used for interpretation of results: expert judgment
Conclusions:
Not irritating to skin

In a OECD guideline and GLP compliant primary skin irritation test in rabbits, the test item caused grade 0-1 erythema after 24 h, while no erythema was observed 48 and 72 hours after application of the test substance. No signs of edema were evident at any time. Therefore, the test item can be regarded as not skin irritating.
Executive summary:

The primary skin irritation potential of the test item was investigated according to OECD test guideline no. 404. The test item was applied by topical semi-occlusive application of 0.5 g to the intact flank of each of three young adult New Zealand White rabbits. The duration of treatment was four hours. The scoring of skin reactions was performed 30 - 60 min, 24, 48 and 72 hours after removal of the dressing. The mean score was calculated across 3 scoring times (24, 48 and 72 hours after patch removal) for each animal for erythema/eschar grades and for edema grades, separately. The application of the test item to the skin resulted in mild signs of irritation such as erythema in one animal after 24 h. This effect was reversible and was no longer evident 48 hours after treatment. No corrosive effects were noted on the treated skin of any animal at any of the measuring intervals and no clinical signs were observed. Thus, the test item did not induce significant or irreversible damage to the skin. Based upon these findings, the test item is considered to be "not irritating" to rabbit skin.