3-(1-ethoxyethyl)-5-methyl-oxazolidin-2-one

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

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

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

3-(1-ethoxyethyl)-5-methyl-oxazolidin-2-one

EC Number:

814-994-6

Cas Number:

123403-95-2

Molecular formula:

C8H15NO3

IUPAC Name:

3-(1-ethoxyethyl)-5-methyl-oxazolidin-2-one

Test material form:

liquid

Test animals / tissue source

Details on test animals or tissues and environmental conditions:

BCOP: Isolated bovine cornea: The test system is the isolated bovine cornea. Bovine eyes are obtained as a by-product of freshly slaughtered cattle (age of the animals: minimum 12 months, maximum 60 months).
Supplier: Schlachthof Mannheim, Mannheim, Germany

Test system

Vehicle:

unchanged (no vehicle)

Controls:

yes

Details on study design:

Experimental procedure BCOP Test
Several test substances were tested in parallel within the present test (test no. 222) by using the same control corneas (NC and PC).
Corneas free of defects (opacity, scratches, pigmentation etc.) were dissected with a 2 to 3 mm rim of sclera. Isolated corneas were mounted in cornea holders that consists of anterior and posterior chambers. Both chambers were filled to excess with pre-warmed Eagle’s MEM (without phenol red) and then equilibrated in a vertical position at about 32°C for at least 1 hour.
After the equilibration period, the medium in both chambers was replaced by fresh pre-warmed medium and initial corneal opacity readings were taken for each cornea with an opacitometer. Any corneas that showed macroscopic tissue damage or an opacity value < 550 opacity units were discarded. The remaining corneas were then distributed into negative control (NC), positive control (PC) and treatment groups.
Each corneal holder was uniquely identified with a number on the chambers.
Each treatment group (test substance, the NC and the PCs) consisted of 3 corneas. Before application, the medium in the anterior chamber was removed by using a syringe. 750 μL undiluted liquid test substance were applied into the anterior chamber by using a pipette.
For the control tissues, 750 μL deionized water (NC) or 750 μL 100% ethanol / 100% dimethylformamide (positive controls, PC1/PC2) were applied into the anterior chamber by using a pipette.
The corneas were incubated in a horizontal position at about 32°C for approximately 10 minutes (liquids and surfactants). The test substance, the NC and the PC were then removed from the anterior chamber by using a syringe and the epithelium was washed at least 3 times with Eagle’s MEM (containing phenol red) and once with Eagle’s MEM (without phenol red). Both chambers were then refilled with fresh Eagle’s MEM (without phenol red).
The corneas were incubated for 2 further hours at about 32°C. After the incubation period, the medium was removed and both chambers were then refilled with fresh Eagle’s MEM.
Before measurement, each cornea was visually observed and observations were recorded.
Final corneal opacity readings were taken for each cornea with an opacitometer.
For determination of permeability, the medium in the anterior chamber was replaced by 1 mL sodium fluorescein solution (4 mg/mL for liquid test substances and surfactants) and incubated for 90 ± 5 minutes in a horizontal position at about 32°C.
The amount of sodium fluorescein that permeated through the corneas into the posterior chamber was spectrophotometrically measured. Three aliquots per cornea were transferred to a 96-well microtiter plate and the optical density (OD490) was determined.

Results and discussion

In vitro

Results

Irritation parameter:

in vitro irritation score

Value:

37

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Any other information on results incl. tables

Test substance identification	Mean Opacity Value	Mean Permeability Value	Mean In Vitro IrritancyScore
17/0010-1	26.6	0.689	37.0
NC	4.2	0.001	4.2
PC1	29.1	0.642	38.7
PC2	90.1	0.222	93.5

Applicant's summary and conclusion

Interpretation of results:

other: not identified as corrosive or severe irritant; no classification can be made for eye irritation, further testing with another suitable method is required

Conclusions:

Based on the results of the BCOP, and by applying the evaluation criteria, 3-(1-Ethoxyethyl)-5-methyloxazolidin-2-on was not identified as corrosive or severe irritant under the test conditions chosen.