Dibutoxy(dimethyl)silane

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

08-01-2015 to 15-01-2015

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study was conducted to the appropriate OECD test guideline and in compliance with GLP.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2015

Report date:

2015

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 437 (Bovine Corneal Opacity and Permeability Test Method for Identifying Ocular Corrosives and Severe Irritants)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Dibutoxy(dimethyl)silane

EC Number:

216-467-0

EC Name:

Dibutoxy(dimethyl)silane

Cas Number:

1591-02-2

Molecular formula:

C10H24O2Si

IUPAC Name:

dibutoxydimethylsilane

Test material form:

other: liquid at room temperature

Details on test material:

- Name of test material (as cited in study report): Dibutoxy(dimethyl)silane
- Physical state: Liquid
- Stability under test conditions: undergoes hydrolysis in water, otherwise stable
- Storage condition of test material: at room temperature, protected from water and moisture, tightly closed and protected well from heat/ignition source

Test animals / tissue source

Species:

other: bovine cornea

Strain:

not specified

Details on test animals or tissues and environmental conditions:

Not relevant

Test system

Vehicle:

unchanged (no vehicle)

Controls:

other: Not relevant

Amount / concentration applied:

Not relevant

Duration of treatment / exposure:

Not relevant

Observation period (in vivo):

Not relevant

Number of animals or in vitro replicates:

Not relevant

Details on study design:

Following preparation of the corneas, calibration of the opacitometer and an equilibration period the medium was removed from both chambers and replaced with fresh complete RPMI 1640 without phenol red. An initial opacity measurement was performed on each of the corneas using an opacitometer (MC2, Clermont, France). Three corneas with opacity readings approximately equivalent to the median opacity of all corneas were selected as negative-control corneas. The opacity of each cornea was read against an air-filled chamber and recorded. Corneas that have an initial opacity reading above 7 units were discarded. The medium was removed from the anterior chamber and replaced with the test item or control.

750 microlitres of the test substance or the control substance were introduced into the anterior chamber (closed-chamber method). After 10 minutes incubation at 32 ± 1 °C either the test substance or the control substance was removed and the epithelium washed at least three times with MEM (containing phenol red). Once the medium was free of test substance, the cornea was finally rinsed with complete RPMI (without phenol red). The anterior chamber was refilled with complete RPMI and an opacity measurement was performed after 2 hours incubation at 32 ± 1 °C.

After the opacity measurement was performed, the medium was removed from both chambers of the holder. The posterior chamber was refilled with fresh complete RPMI. 1 mL of a 4 mg/mL sodium fluorescein solution was added to the anterior chamber and the corneas were incubated for 90 minutes at 32 ± 1 °C. Then the medium from the posterior chamber was removed and its optical density at 490 nm (OD490) was determined, using a spectrophotometer.

3 corneas for the test item
3 corneas as negative controls treated with physiological saline 0.9% NaCl
3 corneas as positive control treated with ethanol 100%
The BCOP assay is considered to be valid if the in vitro irritation score obtained with the positive control falls within the two standard deviations of the current historical mean.
The negative control responses should result in opacity and permeability values that are less than the established upper limits for background bovine corneas treated with the respective negative control (within two standard deviations of the current historical mean).

Results and discussion

In vivo

Results

Irritation parameter:

other: IVIS

Remarks on result:

other: IVIS = 2.51 (Not classified)

Any other information on results incl. tables

The mean in vitro irritation score was calculated to be 2.51.

The in vitro irritation score obtained with the positive control fell within the two standard deviations of the current historical mean and therefore this assay is considered to be valid.

The negative control responses resulted in opacity and permeability values that are less than the established upper limits for background bovine corneas treated with the respective negative control (within two standard deviations of the current historical mean).

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

In an in vitro Bovine Corneal Opacity and Permeability Assay conducted to OECD TG 437 and GLP, the mean in vitro irritation score, based on opacity and permeability values, after 10 min of exposure and 2 h post incubation, was 2.51 for dibutoxy(dimethyl)silane. This result is negative for eye irritation potential.