Ethyl cyanoacetate

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1994

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study and GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1994

Report date:

1994

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

EPA OTS 798.4100 (Skin Sensitisation)

Deviations:

no

GLP compliance:

yes

Type of study:

Buehler test

Test material

Test material information

Constituent 1

Reference substance name:

Ethyl cyanoacetate

EC Number:

203-309-0

EC Name:

Ethyl cyanoacetate

Cas Number:

105-56-6

Molecular formula:

C5H7NO2

IUPAC Name:

ethyl 2-cyanoacetate

Details on test material:

Batch No. 03083263

In vivo test system

Test animals

Species:

guinea pig

Strain:

Dunkin-Hartley

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Age at study initiation: 6 to 7 weeks
- Weight at study initiation: weight range of 320 to 377 g
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: 6 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): ca. 21°C
- Humidity (%): 30 - 70%
- Air changes (per hr): 15 changes per hour
- Photoperiod (hrs dark / hrs light): 12 h dark / 12h light

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

epicutaneous, occlusive

Vehicle:

unchanged (no vehicle)

Induction 2

Concentration / amount:

induction: approximately 0.5ml undiluted ethyl cyanoacetate
challenge: approximately 0.5ml undiluted ethyl cyanoacetate

Challenge

Challenge 1

Route:

epicutaneous, occlusive

Vehicle:

unchanged (no vehicle)

Challenge 2

Concentration / amount:

induction: approximately 0.5ml undiluted ethyl cyanoacetate
challenge: approximately 0.5ml undiluted ethyl cyanoacetate

No. of animals per dose:

10

Details on study design:

A. INDUCTION EXPOSURE
- The skin of the left shoulder region of each animal was clipped free of hair with an electric clipper.
- A 20 x 20 mm patch of surgical gauze was saturated with ca. 1.5 ml of ethyl cyanoacetate, as supplied
- No. of exposures: 3
- Exposure period: one induction application was made on day 1, 8, 15
- Contact of the test substance with the skin was approxitmately 6 hours for each induction exposure
- Evaluation: The challenge sites wwere evaluated 24, 48 and 72 hours after removal of the patches
- Induction of control animals: the 10 control animals were treated similary to the test animals with the exeption that the test compound was omitted
from the induction applications
- The dermal reaction were observed 30 min and ca. 24 h after after each induction application in both controll and test animals

B. CHALLENGE EXPOSURE
- Hair was removed by clipping from a 50 x 50 mm area on the right flank of each animal.
- A 20 x 20 mm patch of surgical gauze was saturated with ca. 1.5 ml of ethyl cyanoacetate, as supplied
- No. of exposures: 1
-The control and test animals were challenged topically two weeks after the final induction using ethyl cyanoacetate
- Contact of the test substance with the skin was approxitmately 6 hours for each induction exposure
- Evaluation: The challenge sites were evaluated 24, 48 and 72 hours after removal of the patches


All animals were observed daily for signs of ill health or toxicity.
The body weight of the animals were recorded on day 1 and on the last day of the observation.

Positive control substance(s):

yes

Remarks:

formalin

Results and discussion

Positive control results:

The sensitivity of the guinea pig strain used is checked periodically with formalin, a known sensitiser. All animals showed dermal reactions.

Any other information on results incl. tables

Clinical signs: No sogns of ill health or toxicity were recorded

Bodyweight: The bodyweight of all guinea pigs increased in a normal way over the period of the study.

Induction: There were no dermal reactions seen in any of the test or control animals.

Challenge:

The "Buehler test" of E.V. Buehler was performed to reveal a possible sensitising potential of

"Ro 1525". Investigations performed were in conformance with EPA OTS 798.4100. Ten female guinea pigs were used as a test substance group and another 10 females were used as a negative control group. There were three epicutaneous induction exposures and one epicutaneous challenge exposure. The test substance was used undiluted for all three induction exposures and for the challenge exposure. The areas of administration were covered occlusive for 6 hours.

General:

All animals survived till the end of the study. No ill health or toxicity effects were noted.

Skin reactions after induction exposures:

The application sites of all control animals were normal at each time.

There were no dermal reactions seen in any of the test or control animals.

Skin reactions after challenge exposure :

There were no dermal reactions seen in any of the test or control animals.

According to the EC Guideline 93/21 the test substance Ethyl cyanoacetate is not sensitising.

 

Applicant's summary and conclusion

Interpretation of results:

not sensitising

Remarks:

Migrated information

Conclusions:

Classification: not sensitizing
Neither in the induction nor in the challenge no dermal reactions were seen in any of the test or control animals.
According to the EC Guideline 93/21 the test substance Ethyl cyanoacetate is not sensitising.

Executive summary:

The "Buehler test" of E.V. Buehler was performed to reveal a possible sensitising potential of Ethyl cyanoacetate. Investigations performed were in conformance with EPA OTS 798.4100. Ten female guinea pigs were used as a test substance group and another 10 females were used as a negative control group. There were three epicutaneous induction exposures and one epicutaneous challenge exposure. The test substance was used undiluted for all three induction exposures and for the challenge exposure. The areas of administration were covered occlusive for 6 hours.

General:

All animals survived till the end of the study. No ill health or toxicity effects were noted.

Skin reactions after induction exposures:

The application sites of all control animals were normal at each time.

There were no dermal reactions seen in any of the test or control animals.

Skin reactions after challenge exposure:

There were no dermal reactions seen in any of the test or control animals.

According to the EC Guideline 93/21 the test substance Ethyl cyanoacetate is not sensitising.