Bis(2-ethoxyethyl) ether

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

migrated information: read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Study period:

13 April 2010 - 29 April 2010

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

GLP compliant study conducted in accordance with international guidelines.The restriction is also due to the use of read across approach: the study was performed not with DEGDEE but with DEGEE, a substance which like DEGDEE is part of the diethylene glycol monoalkyl and dialkyl ethers category. These substances have been demonstrated to be similar in structure, physical/chemical properties and toxicological profile.

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:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

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-ethoxy-2-(2-methoxyethoxy)ethane

EC Number:

213-690-5

EC Name:

1-ethoxy-2-(2-methoxyethoxy)ethane

Cas Number:

1002-67-1

Molecular formula:

C7H16O3

IUPAC Name:

1-ethoxy-2-(2-methoxyethoxy)ethane

Constituent 2

Reference substance name:

Diethylene glycol ethyl methyl ether

IUPAC Name:

Diethylene glycol ethyl methyl ether

Details on test material:

- Name of test material (as cited in study report): Diethylenglycol EM
- Molecular formula (if other than submission substance): C7H16O3
- Analytical purity: >99.8%
- Lot/batch No.: DEG4055316
- Stability in solvent: 24 hours in water, propylene glycol, DMSO, DMF,acetone:olive oil (4+1), and methyl ethyl ketone
- Storage: At room temperature

In vivo test system

Test animals

Species:

mouse

Strain:

CBA

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Age at study initiation: 8 - 12 weeks
- Housing: Single
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: At least 5 days prior to the start of dosing under test conditions after health examination

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 + 2°
- Humidity (%): 45-65
- Photoperiod (hrs dark / hrs light): 12/12

Study design: in vivo (LLNA)

Vehicle:

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

Concentration:

25, 50, and 100%.

No. of animals per dose:

4

Details on study design:

MAIN STUDY
ANIMAL ASSIGNMENT AND TREATMENT
- Name of test method:Method followed OECD 429; no deviations from the guideline
- Criteria used to consider a positive response: A test item is regarded as a sensitiser in the LLNA if the exposure to one or more test
concentrations resulted in 3-fold or greater increase in incorporation of 3HTdR compared to the concurrent control, as indicated by the
stimulation index.
The estimated concentration of test item required to produce an S.I. of 3 is referred to as the EC3 value.

TREATMENT PREPARATION AND ADMINISTRATION:
Each test group of mice was treated by topical (epidermal) application to the dorsal surface of each ear (left and right) with the test item (25µl).
Five days after the first topical application, all mice were administered with 250 µl of 81.7 µCi/ml 3HTdR (corresponds to 20.4 µCi 3HTdR per mouse) by intravenous injection via a tail vein.

Positive control substance(s):

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

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

Remarks on result:

other: Test item concentration S.I. % (w/v) 25 0.73 50 1.03 100 0.69

Results 2

Parameter:

other: disintegrations per minute (DPM)

Remarks on result:

other: see Remark

Remarks:

Test item Measurement DPM DPM per lymph node (b) concentration % (w/v) 25 3520 438.1 50 4984 621.1 100 3345 416.2 b) = Since the lymph nodes of the animals of a dose group were pooled, DPM/node was determined by dividing the measured value by the number of lymph nodes pooled

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 weight of the 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 Criteria used for interpretation of results: EU

Conclusions:

The test item Diethylene glycol methyl ethyl ether was not a skin sensitiser under the described conditions in a Local Lymph Node Assay in Mice.

Executive summary:

DEGDEE and DEGMEE, which is in the above study tested for its skin sensitisation potential in mice, are both part of the diethylene glycol monoalkyl and dialkyl ethers category described and evaluated in the document titled "Category Approach-Read across Diethylene Glycol Diethyl Ether" (2013).

These substances have been demonstrated to be very similar in structure, physical/chemical properties and toxicological profile . Therefore, a read-across from DEGDEE to data obtained with DEGMEE is scientifically justified.