4-(2,5,6,6-tetramethylcyclohex-2-enyl)but-3-en-2-one

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1979

Report date:

1979

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

yes

Remarks:

non-GLP study; no data about purity and no certificate of analysis of the test substance; no details on housing conditions of animals; observations not followed until the reversibility of the effects; different scoring system was followed in the study

GLP compliance:

no

Remarks:

pre-GLP

Test material

Test material information

1

Reference substance name:

Ionone

EC Number:

232-396-8

EC Name:

Ionone

Cas Number:

8013-90-9

Molecular formula:

C13H20O

IUPAC Name:

4-(2,6,6-trimethylcyclohex-1-en-1-yl)but-3-en-2-one

Specific details on test material used for the study:

Ionone

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

- Age at study initiation: 9-12 weeks

Test system

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 mL
- Concentration (if solution): 100 %

Duration of treatment / exposure:

4 hours

Observation period:

72 hours

Number of animals:

Eight

Details on study design:

- Area of exposure: Dorsum
- % coverage: Test substance (0.5 mL) was applied under a semi-occlusive patch to the clipped skin and the patches were held in place with an adhesive tape.
- Type of wrap used: Animals were immobilised in a canvas body sleeve for 4 h after application of the patch.

REMOVAL OF TEST SUBSTANCE
- After the removal of the patches, the application site was wiped clean of excess material.

SCORING SYSTEM: Skin reactions were observed immediately after removal of the patch and after 24, 48 and 72 h and graded according to the following 8-point anchored ordinate scale:
1 = marginal / very slight
2 = slight
3 = fairly distinct
4 = quite distinct
6 = becoming well developed
8 = well developed
10 = becoming severe
12 = severe

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

mean

Time point:

24/48/72 h

Score:

2

Max. score:

12

Reversibility:

not specified

Results 2

Irritation parameter:

edema score

Basis:

mean

Time point:

24/48/72 h

Score:

2

Max. score:

12

Reversibility:

not specified

Irritant / corrosive response data:

A single treatment of Ionone perfumery material produced a slight/moderate effect 24 hours after treatment. The level of reaction subsided to a generally slight reaction 72 hours after treatment. The response was significantly greater than that produced by Diethyl Phthalate which showed no response after 72 hours and consistently less than that produced by Cyclamen Aldehyde and Geraniol which produced a gernerally moderate reaction.

Any other information on results incl. tables

Reaction grades and scores:

1 = marginal / very slight

2 = slight

3 = fairly distinct

4 = quite distinct

6 = becoming well developed

8 = well developed

10 = becoming severe

12 = severe

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Under the conditions of this test Ionone produced slight/moderate skin irritation. It was somewhat less effect than two widely used perfumery ingredients which are routinely used as standard markers in this type of test.
Ionone would not be expected to cause undue skin irritation during normal factory handling.