Ethyl 2-ethylhexanoate

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Acceptable, well-documented study report which meets basic scientific principles.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1977

Report date:

1977

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Freund's Complete Adjuvant Guinea Pig Maximization Test (variation of Magnusson & Kligman method with adjuvant)

GLP compliance:

no

Remarks:

study performed before implementation of GLP

Type of study:

guinea pig maximisation test

Justification for non-LLNA method:

test conducted before first publication of OECD 429 (LLNA test)

Test material

Test material information

Constituent 1

Reference substance name:

Ethyl 2-ethylhexanoate

EC Number:

221-043-3

EC Name:

Ethyl 2-ethylhexanoate

Cas Number:

2983-37-1

Molecular formula:

C10H20O2

IUPAC Name:

ethyl 2-ethylhexanoate

Details on test material:

- Name of test material: 2-Ethyl-ethylcapronat
- Analytical purity: 100%

In vivo test system

Test animals

Species:

guinea pig

Strain:

other: Pirbright white

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Age at study initiation:
- Weight at study initiation: 265 g (mean, test group), 367 (mean, control group)
- Housing: no data
- Diet (e.g. ad libitum): no data
- Water (e.g. ad libitum): no data
- Acclimation period: no data

ENVIRONMENTAL CONDITIONS
- Temperature (°C): no data
- Humidity (%): no data
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): no data

Study design: in vivo (non-LLNA)

Induction

Route:

intradermal

Vehicle:

olive oil

Concentration / amount:

5%

Adequacy of induction:

not specified

Challenge

Route:

epicutaneous, open

Vehicle:

olive oil

Concentration / amount:

1%

Adequacy of challenge:

not specified

No. of animals per dose:

20 (test group), 10 (control group)

Details on study design:

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: 10
- Test groups: 0.1 mL 5% test substance in olive oil 1:1 with FCA
- Control group: -
- Site: intrascapular region
- Frequency of applications: every 2-3 days

B. CHALLENGE EXPOSURE
- No. of exposures: 1
- Day(s) of challenge: 14 d after induction
- Exposure period: 27 h (residual substance was removed 3 h after first reading)
- Test groups: test substance
- Control group: test substance
- Site: right flank
- Concentrations: 1% in olive oil
- Evaluation (hr after challenge): 24 + 48 h

Challenge controls:

no data

Positive control substance(s):

not specified

Results and discussion

In vivo (non-LLNA)

Results

Results 1

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

1%

No. with + reactions:

2

Total no. in group:

20

Clinical observations:

weakly positive; all aminals showed necrosis after FCA injections, later scars

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 1%. No with. + reactions: 2.0. Total no. in groups: 20.0. Clinical observations: weakly positive; all aminals showed necrosis after FCA injections, later scars.

Results 2

Key result

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

1%

No. with + reactions:

3

Total no. in group:

20

Clinical observations:

3 animals with clear positive, 15 animals with weakly irritant reactions

Remarks on result:

other: Reading: 2nd reading. Hours after challenge: 48.0. Group: test group. Dose level: 1%. No with. positive reactions: 3.0. Total no. in groups: 20.0. Clinical observations: 3 animals with clear positive, 15 animals with weakly irritant reactions.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

In this sensitisation study according to a variation of the Magnusson and Kligman procedure test item was regarded as a weak dermal sensitiser.

Executive summary:

In a dermal sensitisation study with 2-Ethyl ethyl capronate (100% a.i.), female adult Pirbright white guinea pigs (20 in test group, 10 in control group) were tested using a variation of the Magnusson and Kligman procedure.

The substance was prepared by blending a 5% preparation of the test substance in olive oil with Freund's adjuvant at a 1:1 ratio. 10 injections were applied at intervals of 2 -3 days into in intrascapular region. 14 d after induction, the test substance was applied epicutaneously to the right flank. Skin reactions were read twice after challenging at intervals of 24 hours.

After 24 h 2/10 animals showed slightly positive reactions. In 3/20 animals, clearly positive reactions were observed 48 hours after challenging. Further 15 animals showed slight skin reactions.

According to these results 2-Ethyl ethyl capronate is a weak dermal sensitiser.