1-Ethoxy-2,3-difluor-4-[4-(trans-4-butylcyclohexyl)-1-cyclohexen-1-yl]-benzene

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2003-07-11 to 2003-10-13

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2003

Report date:

2003

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

adopted 24 April 2002

Deviations:

no

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:

1-[4-(trans-4-ethylcyclohexyl)-1-cyclohexen-1-yl]-3,5-difluorobenzene

EC Number:

612-166-7

Cas Number:

615257-52-8

Molecular formula:

C20H26F2

IUPAC Name:

1-[4-(trans-4-ethylcyclohexyl)-1-cyclohexen-1-yl]-3,5-difluorobenzene

In vivo test system

Test animals

Species:

mouse

Strain:

CBA

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Harlan Netherlands, B.V. Postbus 6174, NL - 5960 AD Horst
- Age at study initiation: 8 - 12 weeks
- Weight at study initiation: 17.6 - 25.0 g
- Housing: groups of 4
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: not specified

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 +/- 3°C
- Humidity (%): 30 - 70%
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: day 1 To: day 5

Study design: in vivo (LLNA)

Vehicle:

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

Concentration:

pre-test for irritation: 1, 2.5, 5 and 10 % (w/v)
main test: 2.5, 5 and 10 % (w/v)

No. of animals per dose:

pre test: 2
main test: 4 (f) per group (3 test groups, 1 control group) total 16 (f)

Details on study design:

RANGE FINDING TESTS:
In a non-GLP conform pre-test in two mice, test item concentrations of 1 %, 2.5 %, 5 % and 10 % (w/v) were tested on one ear each. No irritation effects were observed at these concentrations after a single application. 10 % (w/v) was the highest technically achievable concentration in the chosen vehicle.

MAIN STUDY
ANIMAL ASSIGNMENT AND TREATMENT
- Name of test method: OECD TG 429
- Criteria used to consider a positive response: A test item is regarded as a sensitizer in the LLNA if the following criteria are fulfilled:
- First, that exposure to at least one concentration of the test item resulted in an incorporation of 3HTdR at least 3-fold or greater than that recorded in control mice, as indicated by the stimulation index.
- Second, that the data are compatible with a conventional dose response, although allowance must be made (especially at high topical concentrations) for either local toxicity or immunological suppression.

TREATMENT PREPARATION AND ADMINISTRATION:
- Topical application of 25 µL test item preparation (test group) or vehicle (control group)
- five days after topical application: iv application of 3H-methyl thymidine
- five hours after treatment with 3H-methyl thymidine, necropsy and analysis of the 3H thymidine incorporation in draining lymph nodes

Positive control substance(s):

hexyl cinnamic aldehyde (CAS No 101-86-0)

Statistics:

Dunnets Test

Results and discussion

Positive control results:

Conc. SI
2.5 %: 2.0
5 % 2.3
10 % 2.0

In vivo (LLNA)

Results

Results 1

Key result

Parameter:

SI

Value:

2

Test group / Remarks:

Test Group 2.5 %

Results 2

Key result

Parameter:

SI

Value:

2.3

Test group / Remarks:

Test Group: 5 %

Results 3

Key result

Parameter:

SI

Value:

2

Test group / Remarks:

Test Group: 10 %

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The test item was found to be not a skin sensitiser under the described conditions in this assay.

Executive summary:

In this GLP-compliant LLNA study according to OECD 429, the test material was found to be not a skin sensitiser up to the highest technically achievable concentraion of 10 % in the selected vehicle.