3-methyl-3-(2,2,3,3,3-pentafluoropropoxy)methyl oxetane

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

16 May 2018 - 16 May 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 437 (Bovine Corneal Opacity and Permeability Test Method for Identifying i) Chemicals Inducing Serious Eye Damage and ii) Chemicals Not Requiring Classification for Eye Irritation or Serious Eye Damage)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU method B.47 (Bovine corneal opacity and permeability test method for identifying ocular corrosives and severe irritants)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

482-280-8

EC Name:

-

Cas Number:

449177-94-0

Molecular formula:

C8H11F5O2

IUPAC Name:

3-methyl-3-[(2,2,3,3,3-pentafluoropropoxy)methyl]oxetane

Test material form:

liquid

Details on test material:

Lot No: 2231AM-68E
Expiry date: 01 January 2019
Storage conditions: room temperature in the dark

Test animals / tissue source

Species:

cattle

Strain:

not specified

Details on test animals or tissues and environmental conditions:

Eyes from adult cattle (typically 12 to 60 months old) were obtained from a local abattoir as a by-product from freshly slaughtered animals.

Immediately after slaughter, the eyes were placed in Hanks' Balanced Salt Solution (HBSS) supplemented with antiobiotics (penicillin at 100 IU/mL and streptomycin at 100 µg/mL). They were transported to the test facility over ice packs and refrigerated upon arrival. They were used within 24 hours of receipt.

All eyes were macroscopically examined before and after dissection. Only corneas free of damage were used.

Test system

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent positive control

yes, concurrent negative control

Amount / concentration applied:

0.75 mL of test item or control item was directly applied. The holders were gently tilted back and forth to ensure a uniform application of the item over the entire cornea.

Duration of treatment / exposure:

The corneas were Incubated at 32 ± 1 °C for 10 minutes.

Duration of post- treatment incubation (in vitro):

The holders were incubated, anterior chamber facing forward at 32 ± 1 °C for 120 minutes following the treatment.

Details on study design:

A pre-treatment opacity reading was taken for each cornea using a calibrated opacitometer.

The test item or control were applied directly to the corneas and incubated for 10 minutes at 32 ± 1 °C.

At the end of the exposure period, the test item and control items were removed from the anterior chamber and the cornea was rinsed 3 times with fresh complete EMEM containing phenol red before a final rinse with complete EMEM without phenol red. A post-treatment opacity reading was taken and each cornea was visually observed.

The holders were incubated, anterior chamber facing forward at 32 ± 1 °C for 120 minutes.

After incubation. the holders were removed from the incubator and the medium replaced with fresh EMEM. A final opacity reading was taken and each cornea visually inspected.

Following the final opacity measurement the permability of the corneas to sodium fluorescein was evaluated by incubation with 1mL of sodium fluorescein solution (4 mg/mL) at 32 ± 1 °C for 90 minutes.

After incubation, the medium in the posterior chamber of each holder was decanted and retained. 360 µL of media representing each cornea was dispensed into the appropriate wells of pre-labeled 96-well plate. The optical density was measured at 492 nm (without a reference filter) using the Labtech LT-4500 microplate reader.

Results and discussion

In vitro

Results

Results 1

Irritation parameter:

cornea opacity score

Run / experiment:

Overall score (mean of 3 values)

Value:

0

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

no indication of irritation

Results 2

Irritation parameter:

in vitro irritation score

Run / experiment:

Overall Score

Value:

0.1

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

no indication of irritation

Other effects / acceptance of results:

- Sodium chloride 0.9% w/v was used for the negative control. The test was considered acceptable if the negative control produced an opacity value of <3.0 and a permeability of <0.077. The values obtained for the negative control did meet the acceptance criterion at 0.78 for opacity and 0.060 for permeability.
- Neat ethanol was used for positive control purposes. The test was considered acceptable if the positive control produced an In Vitro Irritancy score between the range of 31.6 to 58.7. The In Vitro Irritancy Score obtained for the positive control was 45.3 and is therefore considered acceptable.

The condition of each cornea were also noted. The corneas treated with the test item were clear post treatment and post incubation. The corneas treated with the negative control item were clear post treatment and post incubation. The corneas treated with the positive control item were cloudy post treatment and post incubation.

Any other information on results incl. tables

Table 1: Individual and Mean Corneal Opacity and Permeability Measurements

Treatment	Cornea Number	Opacity					Permeability (OD492)		In Vitro Irritancy Score
		Pre-Treatment	Post-Treatment	Post Incubation	Post-Incubation minus Pre-Treatment	Corrected value		Corrected value
Negative Control	2	3	3	4	1		0.014
	3	6	5	6	0		0.015
	6	2	2	3	1		0.152
					0.7*		0.060#		1.6
Positive Control	7	5	35	35	30	29.3	1.735	1.675
	10	5	27	26	21	20.3	1.505	1.445
	11	4	33	30	26	25.3	1.010	0.950
						25.0•		1.356•	45.3
Test Item	12	4	4	3	-1	0.0	0.015	0.000
	14	2	3	2	0	0.0	0.052	0.000
	15	2	2	2	0	0.0	0.072	0.012
						0.0•		0.004•	0.1

OD = Optical density      * = Mean of post incubation – pre-treatment     •= Mean corrected value             # = mean permeability

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The in vitro irritancy score for the test item was determined to be 0.1 and therefore the test item does not require classification for eye irritation.

Executive summary:

The purpose of this test was to identify whether the test item would induce serious eye damage upon application to the eye using the Bovine Corneal Opacity and Permeability (BCOP) test method.

The test item along with a positive (ethanol) and negative (Sodium chloride 0.9% w/v) control were applied directly to the eye and the opacity and permeability recorded. The test results obtained for the negative and positive control were within the limits stated and therefore considered acceptable.

The in vitro irritancy score for the test item was determined to be 0.1 and therefore it can be concluded that the test item does not require classification for eye irritation.