Ethyl cyanoacetate

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1992

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:

1992

Report date:

1992

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

no

GLP compliance:

yes

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. T 434
ID No. 3633/81 410

Test animals / tissue source

Species:

rabbit

Strain:

Himalayan

Test system

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

0.1 cm³ undiluted test material

Duration of treatment / exposure:

24 hours

Observation period (in vivo):

1, 24, 48, 72 hours, 6 and 8 days

Number of animals or in vitro replicates:

3

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing: with warm isotonic solution of sodium chloride
- Time after start of exposure: 24 hours

SCORING SYSTEM:cornea score, conjunctivae score, iris score, chemosis score

TOOL USED TO ASSESS SCORE: fluorescein

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

conjunctivae score

Basis:

mean

Time point:

other: 24 - 72 h

Score:

1.22

Reversibility:

fully reversible within: 8 days

Results 2

Irritation parameter:

chemosis score

Basis:

mean

Time point:

other: 24 - 72 h

Score:

0.78

Reversibility:

fully reversible within: 8 days

Results 3

Irritation parameter:

iris score

Basis:

mean

Time point:

other: 24 - 72 h

Score:

0.11

Reversibility:

fully reversible within: 8 days

Results 4

Irritation parameter:

cornea opacity score

Basis:

mean

Time point:

other: 24 - 72 h

Score:

0.78

Reversibility:

fully reversible within: 8 days

Any other information on results incl. tables

Individuell results

	1h			24h			48h			72h			6d			8d
animal	1	2	3	1	2	3	1	2	3	1	2	3	1	2	3	1	2	3
conjunctivae score	2	1	2	2	1	1	2	2	0	2	1	0	1	1	0	0	0
chemosis score	1	1	1	2	1	0	1	1	0	1	1	0	1	0	0	0	0
iris score	0	0	0	1	0	0	0	0	0	0	0	0	0	0	0	0	0
cornea score	0	0	0	1	0	0	2	1	0	2	1	0	0	0	0	0	0
fluorescein test*				2	0	0	1	1	0	1	1	0	0	0	0
exudation	x			x			x			x
- of substance
- white mucous	x			x			x			x
conjunctivae, incl. nictitating membrane- with hemorrhage
iris
- reddened				x
- circumcomeal injection

* the area of the brightening from the cornea surface after instillation of one trop fluorescein (0,1%) is denoted:

0 = no brightening

1 = punctual to 1/4

2 = 1/4 to 1/2

Applicant's summary and conclusion

Interpretation of results:

irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Classification: irritating
The following mean scores were calculated from the individual examinations performed 24 h, 48 h and 72 h p.a.:
Cornea score: 0.78
Conjunctivae score: 1.22
Iris score: 0.11
Chemosis score: 0.78
Ocular lesions were reversible in all animals. A clearly hyperemia respectively a redness and a light swelling of the conjunctivae was observed in all
animals after one hour exposition.
Mean scores for conjunctivae, chemosis and cornea exceed the thresholds for classifying a test substance as "irritating" as set by the EC Guideline 93/21. Criteria for corrosion are not fulfilled.
Therefore the test substance ethyl cyanoacetate is an irritant according to the EC-guideline 93/21.

Executive summary:

Aim of the study

The aim of this study was to investigate possible irritating or corrosive effects of the undiluted test substance following a single administration into a conjunctival sac of rabbits.

Methods

Methods and investigations were performed in conformance with the OECD Guideline 405, 1987.

Administration of the test substance

The equivalent of 0.1 cm³ ethyl cyanoacetate was instilled into the conjunctival sac of one eye of each of 3 rabbits. The eyes were rinsed with warm isotonic solution of sodium chloride after 24 h.

Investigations

Eye examination: 1, 24,48, 72 h and 6,8, d after the administration

Results

General signs

No other than ocular lesions were noted.

Eye examination

A clearly hyperemia respectively a redness and a light swelling of the conjunctivae was observed in all animals after one hour exposition.

Cornea: 1 animal was normal at any time. In 2 animals diffuse opacity of the cornea was present from 48 h to 72 h p.a.

Iris: 2 animals were normal at any time. In one animal mild lesions were observed after 24 h p.a.

Conjunctivae: Pronounced redness was observed in all animals already 1 h p.a.

Chemosis: A light swelling was seen in all animals already 1 h p.a. In 1 animal a clearly swelling with a partial ecetropion of the lid was observed 24 h p.a.

The third animal was without findings after 48 h p.a., the other two animals were without findings after 8 d p.a.