2,2-Difluoroethyl Acetate

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 27 JUNE 2013 to 19 AUGUST 2013.

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Version / remarks:

2012

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

2,2-difluoroethyl acetate

EC Number:

801-773-4

Cas Number:

1550-44-3

Molecular formula:

C4H6F2O2

IUPAC Name:

2,2-difluoroethyl acetate

Test material form:

liquid

Remarks:

clear and colorless.

Test animals / tissue source

Species:

rabbit

Strain:

other: New Zealand Albino.

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: animals were received from Robinson Services, Inc. Mocksville, NC, USA.
- Sex: female, nulliparous and non-pregnant.
- Age at study initiation: young adult.
- Weight at study initiation: the initial weight ranged from 1893 g to 2360 g, see Table 1 below in section "Any other information on results incl. tables".
- Housing: the animals were individually housed in suspended stainless steel caging with mesh floors which conform to the size recommendations in the Guide for the Care and Use of Laboratory Animals (Natl. Res. Council, 2011). Enrichment (e.g. toy) was placed in each cage. Litter paper was placed beneath the cage and was changed at least three times per week.
- Diet: Harlan Teklad Global High Fiber Rabbit Diet® #2031. A designated amount of the diet was available to each rabbit (approximately 150 grams/day).
- Water: filtered tap water was supplied ad libitum.
- Acclimation period: 5 or 13 days.

ENVIRONMENTAL CONDITIONS
- Temperature: 18-22°C.
- Humidity: 68-86%. The humidity was above the targeted upper limit for five days during the study. A portable dehumidifier was used to lower the humidity levels during this time.
- Air changes (per hr): 12. Airflow measurements were evaluated regularly.
- Photoperiod: 12 hour light/dark cycle.

IN-LIFE DATES: From: 8 July 2013 to 19 July 2013.

Test system

Vehicle:

unchanged (no vehicle)

Controls:

other: The other eye of each rabbit remained untreated and served as a control.

Amount / concentration applied:

TEST MATERIAL
- Amount applied: one-tenth of a millilitre of the test material was instilled into the conjunctival sac of the right eye of each rabbit.
- Concentration: undiluted test material.

Duration of treatment / exposure:

Single instillation into the conjunctival sac of one of the eyes by pulling the lower lid away from the eyeball. The upper and lower lids were then gently held together for about one second before releasing to minimize loss of the test substance. After 24 hours, the treated eyes were rinsed with physiological saline (0.9% NaCl) in the context of the fluorescein dye evaluation procedure used to verify the absence of corneal damage.

Observation period (in vivo):

72 hours.

Number of animals or in vitro replicates:

3 animals.
Initially, only one rabbit was placed on test. In the absence of ocular irritation in this animal, the remaining two animals were tested to confirm the result.

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing and time after start of exposure: After 24 hours, the treated eyes were rinsed with physiological saline (0.9% NaCl) in the context of the fluorescein dye evaluation procedure used to verify the absence of corneal damage.

SCORING SYSTEM:
- Draize et al. system.

TOOL USED TO ASSESS SCORE:
- Ocular irritation was evaluated using a high-intensity white light at 1, 24, 48, and 72 hours post-instillation.
- Corneal damage: using the fluorescein dye evaluation procedure at 24 hours. One drop of 2% ophthalmic fluorescein sodium was instilled into both eyes of each rabbit. The eyes were rinsed with physiological saline (0.9% NaCl) after instillation of the fluorescein and then evaluated for corneal damage using an ultraviolet light source.
- In addition to observations of the cornea, iris and conjunctivae, any other observed lesions were noted. The average score for all rabbits at each scoring period was calculated to aid in data interpretation.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

chemosis score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

0

Reversibility:

other: Not applicable since there was no irritation observed.

Results 2

Irritation parameter:

chemosis score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

0

Reversibility:

other: Not applicable since there was no irritation observed.

Results 3

Irritation parameter:

chemosis score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

0

Reversibility:

other: Not applicable since there was no irritation observed.

Results 4

Irritation parameter:

conjunctivae score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

0

Reversibility:

other: Not applicable since there was no irritation observed.

Results 5

Irritation parameter:

conjunctivae score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

0

Reversibility:

other: Not applicable since there was no irritation observed.

Results 6

Irritation parameter:

conjunctivae score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

0

Reversibility:

other: Not applicable since there was no irritation observed.

Results 7

Irritation parameter:

iris score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

0

Reversibility:

other: Not applicable since there was no irritation observed.

Results 8

Irritation parameter:

iris score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

0

Reversibility:

other: Not applicable since there was no irritation observed.

Results 9

Irritation parameter:

iris score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

0

Reversibility:

other: Not applicable since there was no irritation observed.

Results 10

Irritation parameter:

cornea opacity score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

0

Reversibility:

other: Not applicable since there was no irritation observed.

Results 11

Irritation parameter:

cornea opacity score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

0

Reversibility:

other: Not applicable since there was no irritation observed.

Results 12

Irritation parameter:

cornea opacity score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

0

Reversibility:

other: Not applicable since there was no irritation observed.

Irritant / corrosive response data:

There was no ocular irritation observed in any treated eye during the study. See Tables 2 and 3 in "Any other information on results incl. tables".

Other effects:

- Body weight: All animals gained body weight during the study. See more details in Table 1 in the field “Any other information on results incl. tables”.
- Clinical signs: All animals appeared active and healthy during the study. There were no clinical signs observed.

Any other information on results incl. tables

Table 1: Individual body weights

Animal No.	Sex	Body weight (g)
		Initial	Terminal
3401	F	2208	2289
3402	F	1893	1957
3403	F	2360	2426

 

Table 2: Individual scores for ocular irritation.

		Rabbit No. 3401				Rabbit No. 3402				Rabbit No. 3403
		Hours				Hours				Hours
		1	24	48	72	1	24	48	72	1	24	48	72
Cornea	Opacity	0	0^1	0	0	0	0^1	0	0	0	0^1	0	0
	Area	4	4	4	4	4	4	4	4	4	4	4	4
Iris	Values	0	0	0	0	0	0	0	0	0	0	0	0
Conjunctivae	Redness	0	0	0	0	0	0	0	0	0	0	0	0
	Chemosis	0	0	0	0	0	0	0	0	0	0	0	0
	Discharge	0	0	0	0	0	0	0	0	0	0	0	0

¹ 2% ophthalmic fluorescein sodium used to verify the absence of corneal opacity. 

 

Table 3: Mean scores for individual rabbits

Rabbit Number	Corneal Opacity^a	Iritis^a	Conjunctival Redness^a	Conjunctival Chemosis^a
3401	0.0	0.0	0.0	0.0
3402	0.0	0.0	0.0	0.0
3403	0.0	0.0	0.0	0.0

^a Calculated from the 24-, 48-, and 72-hour scores (EEC/GHS).

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Under the conditions of this study, 2,2-Difluoroethyl acetate did not induce eye irritation in rabbits.

Executive summary:

The eye corrosion/irritation potential of 2,2-Difluoroethyl acetate was investigated in a study performed according to OECD test guideline 405 under GLP compliance.

The study was carried out with three female New Zealand albino rabbits. Initially, one rabbit was treated as follows: 0.1 mL of the test substance was instilled into the conjunctival sac of the right eye by pulling the lower lid away from the eyeball. The upper and lower lids were then gently held together for about one second before releasing to minimize loss of the test substance. The other eye remained untreated with the test substance and served as a control. The rabbit was then returned to its cage. Ocular irritation was evaluated by the method of Draize et al. (1944) at 1, 24, 48, and 72 h post-instillation. Since there was no ocular irritation noted in this animal, the test was completed on two additional animals, as described above.

No clinical signs of toxicity were observed in the study. None of the three rabbits tested showed ocular irritation.

Under the conditions of this study, 2,2-Difluoroethyl acetate did not induce ocular irritation in rabbits.