Diethyl ether

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study with detailed documentation.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Deviations:

yes

Remarks:

humidity was 18% percent for a few hours

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.42 (Skin Sensitisation: Local Lymph Node Assay)

Deviations:

not specified

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:

Diethyl ether

EC Number:

200-467-2

EC Name:

Diethyl ether

Cas Number:

60-29-7

Molecular formula:

C4H10O

IUPAC Name:

diethyl ether

Details on test material:

- Name of test material (as cited in study report): diethyl ether
- Physical state: liquid
- Analytical purity: 99.93%
- Lot/batch No.: 09023198
- Stability under test conditions: Not reported
- Storage condition of test material: at room temperature

- Radiochemical purity (if radiolabelling): 3H-Methyl-thymidine: from GE healthcare 74 GBq/mmol (2 Ci/mmol), 37 MBq/mL (1 mCi/mL)

In vivo test system

Test animals

Species:

mouse

Strain:

CBA

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Harlan Laboratories BV Postbus 6174 5960 AD Horst/The Netherlands
- Age at study initiation: 8 to 12 weeks
- Weight at study initiation: 18.6 to 22.1 g
- Housing: singly in makrolon type 11 with wire mesh top and granulated soft wood bedding
- Diet (e.g. ad libitum): pelleted standard diet, ad libitum (from Harlan Laboratories BV Postbus 6174 5960 AD Horst/The Netherlands)
- Water (e.g. ad libitum): tap water, ad libitum
- Acclimation period: at least 5 days prior to the start of the dosing under test conditions


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 16 to 20
- Humidity (%): 18 to 65
- Air changes (per hr): not reported
- Photoperiod (hrs dark / hrs light): 12/12

Study design: in vivo (LLNA)

Vehicle:

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

Concentration:

25, 50, or 100%

No. of animals per dose:

4 females per group

Details on study design:

MAIN STUDY
ANIMAL ASSIGNMENT AND TREATMENT
- Name of test method:LLNA
- Criteria used to consider a positive response: a test item is regarded as a sensitizer if (1) the 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 indication by the stimulation index, and (2) that the data are comparable with a conventional dose response


TREATMENT PREPARATION AND ADMINISTRATION:

Topical Application - Each test group of mice was treated by a topical (epidermal) application to the dorsal surface of each ear (left and right) with different test item concentrations of 25, 50, or 100% in acetone:olive oil (4:1). The application volume was spread over the entire dorsal surface of each ear once daily for three consecutive days. A further group was treated with the vehicle alone.

Five days after the first topical application, all mice were administered with 250 microliters of 78.3 microCi/ml 3HTdR by intravenous injection via a tail vein. Approximately 5 hours after treatment with 3HTdR all mice were euthanized buy intraperitonal injection of Pentobarbial-Natrium. The draining lymph nodes were excised and pooled. Single-cell suspensions were prepared and washed with phosphate buffered saline twice and then suspended in 5% tricholoracetic acid. Then the cells were incubated for 18 hours and the precipatates were resuspended in 5% tricholoracetic acid and transferred to plastic scintillation vials and mixed. The level of 3HtdR incorporation was measured on a beta-scintillation counter.

Positive control substance(s):

other: none

Statistics:

The mean values and standard deviations were calculated in the body weight tables.

Results and discussion

In vivo (LLNA)

Results

Results 1

Parameter:

SI

Value:

0.45

Test group / Remarks:

25% in acteone:olive oil (4 : 1)

Results 2

Parameter:

SI

Value:

0.66

Test group / Remarks:

50% in acteone:olive oil (4 : 1)

Results 3

Parameter:

SI

Value:

0.54

Test group / Remarks:

100% in acteone:olive oil (4 : 1)

Any other information on results incl. tables

No deaths occurred during the study period. No symptoms of local toxicity at the ears of the animals and no systemic findings were observed during the study period. The body weights of animals, recorded prior to the first application and prior to treatment with 3HTdR, was within the range commonly recorded for animals of this strain and age.

Applicant's summary and conclusion

Interpretation of results:

not sensitising

Remarks:

Migrated information