6-methyloct-5-en-2-one

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

18.09.2007 - 15.02.2008

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: According to guideline under GLP

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2008

Report date:

2008

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay)

Deviations:

no

Principles of method if other than guideline:

Not relevant

GLP compliance:

yes (incl. QA statement)

Type of study:

mouse local lymph node assay (LLNA)

Test material

Test material information

Constituent 1

Reference substance name:

6-methyloct-5-en-2-one

EC Number:

246-073-4

EC Name:

6-methyloct-5-en-2-one

Cas Number:

24199-46-0

Molecular formula:

C9H16O

IUPAC Name:

6-methyloct-5-en-2-one

In vivo test system

Test animals

Species:

mouse

Strain:

CBA

Sex:

female

Study design: in vivo (LLNA)

Vehicle:

acetone/olive oil (4:1 v/v)

Concentration:

25, 50, 100%

No. of animals per dose:

4

Results and discussion

In vivo (LLNA)

Results

Results 1

Parameter:

SI

Remarks on result:

other: SI 25%: 1.76; SI 50%: 2.45; SI 100%: 3.87

Results 2

Parameter:

other: disintegrations per minute (DPM)

Remarks on result:

other: 25%: 10112; 50%: 14056; 100%: 22224 DPM

Applicant's summary and conclusion

Interpretation of results:

sensitising

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The test item Ethylheptenone Technical was found to be a skin sensitiser under the described conditions.

Executive summary:

In order to study a possible contact allergenic potential of Ethylheptenone Technical, three groups each of four female mice were treated daily with the test item at concentrations of 25 and 50% (w/v) in acetone:olive oil (4+1, v/v), respectively, as well as 100% (undiluted as supplied by the sponsor) by topical application to the dorsum of each ear lobe (left and right) for three consecutive days. A control group of four mice was treated with the vehicle (acetone:olive oil (4+1, v/v)) only. Five days after the first topical application the mice were injected intravenously into a tail vein with radio-labelled thymidine (3H-methyl thymidine). Approximately five hours after intravenous injection, the mice were sacrificed, the draining auricular lymph nodes excised and pooled per group. Single cell suspensions of lymph node cells were prepared from pooled lymph nodes, which were subsequently washed and incubated with trichloroacetic acid overnight. The proliferative capacity of pooled lymph node cells was determined by the incorporation of 3H-methyl thymidine measured in abeta- scintillation counter. All treated animals survived the scheduled study period and no signs of toxicity were observed. A test item is regarded as a sensitiser in the LLNA if the exposure to one or more test concentration resulted in 3-fold or greater increase in incorporation of 3HTdR compared with concurrent controls, as indicated by the Stimulation Index (S.I.). The estimated concentration of test item required to produce a S.I. of 3 is referred to as the EC3 value. In this study Stimulation Indices (S.I.) of 1.76, 2.45, and 3.87 were determined with the test item at concentrations of 25, 50, and 100% in acetone:olive oil (4+1, v/v), respectively. The test item Ethylheptenone Technical was found to be a skin sensitiser and an EC3 value of 69.3 % (w/v) was derived.