Ethyl 2-methyl-4-oxo-6-pentylcyclohex-2-ene-1-carboxylate

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

September 1986

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study without detailed documentation

Justification for type of information:

The study was performed on a similar substance to the registered substance and as such is considered to be sufficient to address the endpoint by read-across.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1986

Report date:

1986

Materials and methods

Test guideline

Qualifier:

no guideline available

Principles of method if other than guideline:

0.5 ml (or 0.2g) of the test material is applied to a semi-occlusive patch which is then placed on the clipped dorsum of rabbits. The patch remains on the animal for four hours. Irritation reactions are assessed immediately after removal of the patch and thereafter at 24, 48 and 72 hours.

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Methyl 3-oxo-2-pentylcyclopentaneacetate

EC Number:

246-495-9

EC Name:

Methyl 3-oxo-2-pentylcyclopentaneacetate

Cas Number:

24851-98-7

Molecular formula:

C13H22O3

IUPAC Name:

Methyl 3-oxo-2-pentyl-1-cyclopentaneacetate

Specific details on test material used for the study:

Test material name (as stated in the report) : Methyl Dihydrojasmonate (S15102-T01)

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

Animals bought from a commercial supplier are used for testing the hair is in a non-growth (telogen) phase of the hair cycle.
Three to four days prior to the testing the backs and flanks of 9 to 12 week old rabbits are cliipped to identify those which are in telogen and which have no skin blemishes. Of these rabbits, 8 are selected for the test. The hair is given a final clip approximately 2 hours prior the treatment. Throughout the test the rabbit are housed individually in suspended cages with wire mesh floor. They have free access to tap water and pelleted rabbit diet with vitamin and mineral supplements.

Test system

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

0.5 ml of test substance (100% concentration) is applied

Duration of treatment / exposure:

4 hours

Observation period:

24, 48 and 72 hours after treatment

Number of animals:

8 rabbits

Details on study design:

The test material is applied to every rabbit in this test: up to 6 patches can be applied to each rabbit. Prior to treatment a plan (based on random number sequence) is prepared on application sites of each substance on each rabbit. When all patches have been applied to a rabbit it is immobilized in a canvas body sleeve and placed in a quiet place for the 4 hour application period, at the end, of which the animals are removed from the body sleeves and the corners of each treatment site marketed. The patches are then removed and excess substance wiped from the skin with damp tissue.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal: 1331; 1352 and 1410

Time point:

24/48/72 h

Score:

1

Max. score:

1

Reversibility:

not fully reversible within: 72 hours

Remarks:

hours

Results 2

Irritation parameter:

erythema score

Basis:

animal: 1412

Time point:

24/48/72 h

Score:

1.33

Max. score:

2

Reversibility:

not fully reversible within: 72

Remarks:

hours

Results 3

Irritation parameter:

erythema score

Basis:

animal: 1415;1419 and 1420

Time point:

24/48/72 h

Score:

0.66

Max. score:

1

Reversibility:

fully reversible within: 72

Remarks:

hours

Results 4

Irritation parameter:

erythema score

Basis:

animal: 1416

Time point:

24/48/72 h

Score:

1.66

Max. score:

2

Reversibility:

not fully reversible within: 72

Remarks:

hours

Results 5

Irritation parameter:

edema score

Basis:

animal: 1412

Time point:

24/48/72 h

Score:

1

Max. score:

1

Reversibility:

not fully reversible within: 72

Remarks:

hours

Results 6

Irritation parameter:

edema score

Basis:

animal: 1331; 1352; 1410 and 1419

Time point:

24/48/72 h

Score:

0.66

Max. score:

1

Reversibility:

other: fully reversible within 72 hours: 1352 and 1419

Remarks on result:

other: Not fully reversible within 72 hours: 1331; 1410

Results 7

Irritation parameter:

edema score

Basis:

animal: 1416

Time point:

24/48/72 h

Score:

1.33

Max. score:

2

Reversibility:

not fully reversible within: 72

Remarks:

hours

Results 8

Irritation parameter:

edema score

Basis:

animal: 1415 and 1420

Time point:

24/48/72 h

Score:

0.33

Max. score:

1

Reversibility:

fully reversible within: 72

Remarks:

hours

Irritant / corrosive response data:

Immediately after removal of the patches, all eight animals showed slight erythema and/or slight oedema. 72 hours after patch removal these effects had reduced in nine animals to show very slight erythema and/or slight oedema in four animals with three animals entirely normal. The remaining animals showed slight/moderate erythema/oedema at 72 hours.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Under the conditions of this test, Methyl Dihydrojasmonate (S15102-T01) showed slight irritancy, nevertheless the effects observed do not met the criteria for skin irritation classication according the CLP Regulation (EC) No. 1272/2008.

Executive summary:

Methyl Dihydrojasmonate is tested to demonstrate the skin irritation potential. 0.5 ml (or 0.2g) of the test material is applied to a semi-occlusive patch which is then placed on the clipped dorsum of rabbits. The patch remains on the animal for four hours. Irritation reactions are assessed immediately after removal of the patch and thereafter at 24, 48 and 72 hours. Immediately after removal of  the patches, all eight animals showed slight erythema and/or slight oedema. 72 hours after patch removal these effects had reduced in four animals to show very slight erythema and/or slight oedema with three animals entirely normal. The remaining animals showed slight/moderate erythema/oedema at 72 hours.

Therefore it can be concluded that under the conditions of this test, Methyl Dihydrojasmonate (S15102-T01) showed slight irritancy, nevertheless the effects observed do not met the criteria for classication according the CLP Regulation (EC) No. 1272/2008.