Ethyl 2-cyclohexylpropionate

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 11 to 25 November 1991

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: According to the Directive 84/449/EEC Part B, Method B.5 and it is 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:

EU Method B.5 (Acute Toxicity: Eye Irritation / Corrosion)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Ethyl 2-cyclohexylpropionate

EC Number:

412-280-5

EC Name:

Ethyl 2-cyclohexylpropionate

Cas Number:

2511-00-4

Molecular formula:

C11H20O2

IUPAC Name:

ethyl 2-cyclohexylpropanoate

Details on test material:

- Physical state: clear liquid
- Storage condition of test material: 4ºC in the dark

Test animals / tissue source

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: Froxfield (Uk) Ltd., Petersfield, Hampshire, England
- Age at study initiation: 13-15 week
- Weight at study initiation: 3.1-3.6 kg
- Housing: individually in metal cages
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19
- Humidity (%): 30-70
- Air changes (per hr): 19
- Photoperiod (hrs dark / hrs light): 12/12

Test system

Vehicle:

unchanged (no vehicle)

Controls:

other: the cobtralateral eye remained untreated

Amount / concentration applied:

The eyes of each animal were examined prior to instillation of the test substance to ensure that there was no pre-existing corneal damage, iridial or conjunctival inflammation.
One animal was treated in advance of the others, to ensure that if a severe response was produced, no further animals would be exposed (pilot animal see Table 1).
0.1 mL amount of the test substance was placed into the lower everted lid of one eye of each animals.

Duration of treatment / exposure:

Examination of the eyes was made after 1 hour 1,2,3 (equivalent to 24,48 and 72 hours after instillation), 4 and 7 after instillation

Observation period (in vivo):

Observation of the eyes was aided by the use of a handheld light.

Number of animals or in vitro replicates:

Three animals: Male (pilot animal), one male and one female.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

cornea opacity score

Basis:

mean

Time point:

other: after 7 days

Max. score:

0

Reversibility:

fully reversible

Results 2

Irritation parameter:

iris score

Basis:

mean

Time point:

other: after 7 days

Max. score:

0

Reversibility:

fully reversible

Results 3

Irritation parameter:

chemosis score

Basis:

mean

Time point:

other: after 7 days

Max. score:

0

Reversibility:

fully reversible

Results 4

Irritation parameter:

conjunctivae score

Basis:

mean

Time point:

other: after 2 days

Max. score:

1

Reversibility:

fully reversible

Irritant / corrosive response data:

CLINICAL SIGNS
There were no signs of toxicity or ill health in any rabbit during the observation period.
OCULAR RESPONSES
The numerical values given to the ocular reactions elicited by the test substance are shown in Table 1.
No corneal damage or iridial inflammation was observed.
Temporary mild conjunctival reactions only were seen.
The eyes were normal 2 to 3 days after instillation.

Any other information on results incl. tables

TABLE 1
Ocular reactions observed after instillation of the test substance
Rabbit number and sex	Region of eye		One hour	Day after instillation
				1	2	3	4	7
1873 Male *	Cornea		0	0	0	0	0	0
	Iris		0	0	0	0	0	0
	Conjunctiva	Redness	2	2	1	0	0	0
		Chemosis	2	2	0	0	0	0
1961 Male	Cornea		0
	Iris		0
	Conjunctiva	Redness	2
		Chemosis	2
1962 Female	Cornea		0
	Iris		0
	Conjunctiva	Redness	2
		Chemosis	2
*Pilot animal

Applicant's summary and conclusion

Interpretation of results:

slightly irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Instillation of the test substance into the rabbit eye elicited temporary mild conjunctival irritation only.

Executive summary:

A study was performed to assess the eye irritation potential of the test substance to the rabbit. The method followed was that described in the EEC Methods for the determination of toxicity, Directive 84/449/EEC Part B, Method B.5. Acute toxicity (eye irritation).

Three rabbits were each administered a single ocular dose of 0.1 ml of the test substance and observed for a maximum of 7 days after instillation. A single instillation of the test substance into the eye of the rabbit elicited temporary mild conjuntival irritation. All reactions had resolved 2 to 3 days after instillation.

The test substance does not require labelling with the risk phrase R36 "Irritating to eyes", in accordance with Council Directive 79/831/EEC, Annex VI, Part II (D) as described in Commission Directive 91/325/EEC.