Methyl 2-ethylhexanoate

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2003

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study performed under GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2003

Report date:

2003

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2400 (Acute Eye Irritation)

Deviations:

no

Test guideline 2

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:

Methyl 2-ethylhexanoate

EC Number:

212-429-2

EC Name:

Methyl 2-ethylhexanoate

Cas Number:

816-19-3

Molecular formula:

C9H18O2

IUPAC Name:

methyl 2-ethylhexanoate

Test material form:

other: liquid

Details on test material:

- Physical state: Liquid
- Storage condition of test material: Room temperature.
- Other: Clear colourless

Test animals / tissue source

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: Recognised supplier
- Age at study initiation: Young adult
- Weight at study initiation: Not reported.
- Housing: individually housed in labeled cages with mesh floors conform to the size recommendations in the most recent Guide for the Care
and Use of Laboratory Animals DHEW (NIH)
- Diet (e.g. ad libitum): Pelleted Purina Rabbit Chow #5326
- Water (e.g. ad libitum): filtered tap water ad libitum
- Acclimation period: 7 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19 - 22
- Humidity (%): Not reported.
- Air changes (per hr):Not reported.
- Photoperiod (hrs dark / hrs light): 12 hour light/12 hour dark cycle

IN-LIFE DATES: From: 22/10/03 To: 22/10/03

Test system

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.75 mL
- Concentration (if solution): undiluted

Duration of treatment / exposure:

72 hours

Observation period (in vivo):

Ocular irritation was evaluated at 1, 24, 48, and 72 hours post-instillation

Number of animals or in vitro replicates:

3. 1 male and 2 females

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing (if done): none

SCORING SYSTEM:
The irritation was assessed according to the following numerical scoring system and Draize et al. at 1, 24, 48, and 72 hours post-instillation. The fluorescein dye evaluation procedure was used at 24 hours to verify the absence of corneal damage. Individual scores were recorded for each animal.:

1. Cornea
A. Opacity-degree of density (area most dense taken for reading)
No Opacity 0
Scattered or diffuse area, details of iris clearly visible 1 #
Easily discernible translucent areas, details of iris slightly obscured 2 #
Opalescent areas, no details of iris visible, size of pupil barely discernible 3 #
Opaque, iris invisible 4 #
B. Area of cornea involved
One quarter (or less) but not zero 1
Greater than one quarter, but less than half 2
Greater than half, but less than three quarters 3
Greater than three quarters, up to whole area 4
A X B X 5 Total Maximum= 80

2. Iris
A. Values
Normal 0
Folds above normal, congestion, swelling, circumcorneal injection (any or all of these or combination of any thereof) iris still reacting to light (sluggish reaction is positive) 1 #
No reaction to light, haemorrhage, gross destruction (any or all of these) 2 #
A X 5 Total Maximum= 10

3. Conjunctivae
A. Redness (refers to palpebral and bulbar conjunctivae excluding cornea and iris)
Vessels normal 0
Vessels definitely injected above normal 1
More diffuse, deeper crimson red, individual vessels not easily discernible 2 #
Diffuse beefy red 3 #
B. Chemosis
No swelling 0
Any swelling above normal (includes nictitating membrane) 1
Obvious swelling with partial eversion oflids 2 #
Swelling with lids about half-closed 3 #
Swelling with lids about half-closed to completely closed 4 #

C. Discharge
No discharge 0
Any amount different from normal (does not include small amounts observed in inner canthus of normal animals) 1
Discharge with moistening of the lids and hairs just adjacent to lids 2
Discharge with moistening of the lids and hairs, and considerable area around the eye 3
Score (A+ B + C) X 2 Total Maximum= 20

Total Maximum Score: 110 represents the sum of all scores obtained for the cornea, iris and conjunctivae.
# These scores represent a positive response.

TOOL USED TO ASSESS SCORE: ophthalmic examination lamp

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

maximum mean total score (MMTS)

Basis:

mean

Time point:

other: 1h

Score:

4

Max. score:

110

Reversibility:

fully reversible within: 72h

Results 2

Irritation parameter:

cornea opacity score

Basis:

mean

Time point:

other: 24, 48, 72 hours

Score:

0

Max. score:

4

Results 3

Irritation parameter:

iris score

Basis:

mean

Time point:

other: 24, 48, 72 hours

Score:

0

Max. score:

2

Results 4

Irritation parameter:

conjunctivae score

Basis:

mean

Time point:

other: 24, 48, 72 hours

Score:

0.55

Max. score:

3

Reversibility:

fully reversible

Results 5

Irritation parameter:

chemosis score

Basis:

mean

Time point:

other: 24, 48, 72 hours

Score:

0

Max. score:

4

Irritant / corrosive response data:

There was no corneal opacity or iritis observed during this study. One hour after test substance instillation, all three treated eyes exhibited conjunctivitis. The overall incidence and severity of irritation decreased with time. All animals were free of ocular irritation by 72 hours. See table 2.

Other effects:

There were no other signs of gross toxicity, adverse pharmacologic effects or abnormal behaviour.

Any other information on results incl. tables

Table 2. Individual Scores for Ocular Irritation

	Test organism 1 (female)				Test organism 2 (male)				Test organism 3 (male)
	Hours				Hours				Hours
	1	24	48	72	1	24	48	72	1	24	48	72
Cornea
A. Opacity	0	0 #2	0	0	0	0 #2	0	0	0	0 #2	0	0
B. Area	4	4	4	4	4	4	4	4	4	4	4	4
AxBx5	0	0	0	0	0	0	0	0	0	0	0	0
Iris
A. Values	0	0	0	0	0	0	0	0	0	0	0	0
Ax5	0	0	0	0	0	0	0	0	0	0	0	0
Conjunctivae
A. Redness	2	1	1	0	2	1	1	0	2	1	0	0
B. Chemosis	0	0	0	0	0	0	0	0	0	0	0	0
C. Discharge	0	0	0	0	0	0	0	0	0	0	0	0
(A+B+C)x2	2	1	1	0	2	1	1	0	2	1	0	0
Total	4	2	2	0	4	2	2	0	4	2	0	0

# 2% ophthalmic fluorescein sodium used to verify the absence of corneal opacity.

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Under the conditions of this study the test substance cannot be considered as eye irritant.

Executive summary:

The study was performed according to US EPA OPPTS 870.2400 and OECD 405 acute eye irritation in vivo and in accordance with GLP. A volume of 0.1 ml of the test material was placed into the conjunctival sac of one eye of 3 animals. The other eye remained untreated and was used for control purposes. Assessment of ocular damage/irritation was made approximately 1 hour and 24, 48 and 72 hours following treatment. There was no corneal opacity or iritis observed during this study. One hour after test substance instillation, all three treated eyes exhibited conjunctivitis. The overall incidence and severity of irritation decreased with time. All animals were free of ocular irritation by 72 hours. All animals appeared active and healthy. There were no other signs of gross toxicity, adverse pharmacologic effects or abnormal behaviour. Under the conditions of this study the test material is mildly irritating. Based on applicant’s calculation of the mean scores following grading at 24, 48 and 72h and the individual scores, the test material is not considered to be irritating to the eye under Regulation (EC) 1272/2008 criteria.