Octaphenylcyclotetrasiloxane

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

30th May 2017 to 07th June 2017

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)

Version / remarks:

2013

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Octaphenylcyclotetrasiloxane

EC Number:

208-904-9

EC Name:

Octaphenylcyclotetrasiloxane

Cas Number:

546-56-5

Molecular formula:

C48H40O4Si4

IUPAC Name:

octaphenyl-1,3,5,7,2,4,6,8-tetraoxatetrasilocane

Test material form:

solid

Details on test material:

- Density: 1.185 g/cm3

Specific details on test material used for the study:

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: at room temperature
- Stability under test conditions: stable
- Solubility and stability of the test substance in the solvent/vehicle: the test substance was stable in corn oil
- Reactivity of the test substance with the solvent/vehicle of the cell culture medium: not applicable

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: The test material was suspended with corn oil to give 20% concentration.
- Preliminary purification step (if any): not specified

Test animals / tissue source

Species:

other: animals freshly slaughtered at the abattoir

Strain:

not specified

Details on test animals or tissues and environmental conditions:

SOURCE OF COLLECTED EYES
- Source: animals freshly slaughtered at the abattoir A. Moksel AG, Buchloe, Germany
- Number of animals: not specified
- Characteristics of donor animals (e.g. age, sex, weight): not specified
- Storage, temperature and transport conditions of ocular tissue (e.g. transport time, transport media and temperature, and other conditions): On the test day, fresh eyes were collected from the slaughterhouse and were transported in HBSS containing Pen/Strep on ice to the laboratories.
- Time interval prior to initiating testing: Immediately after arrival of the eyes, cornea preparation was initiated.
- indication of any existing defects or lesions in ocular tissue samples: The eyes were carefully examined for defects and any defective eyes were discarded.
- Indication of any antibiotics used: Not specified

Test system

Vehicle:

other: corn oil

Controls:

yes, concurrent vehicle

yes, concurrent positive control

yes, concurrent negative control

Amount / concentration applied:

TEST MATERIAL
- Concentration (if solution): 750 µL of the test item preparation

VEHICLE
- Amount(s) applied (volume or weight with unit):
- Concentration (if solution): 750 µL

Duration of treatment / exposure:

4 hours ± 5 minutes incubation at 32 ± 1 °C.

Duration of post- treatment incubation (in vitro):

90 minutes at 32 ± 1 °C

Number of animals or in vitro replicates:

3 corneas for test item

Details on study design:

SELECTION AND PREPARATION OF CORNEAS: The assay uses isolated corneas obtained as a by-product from animals freshly slaughtered at the abattoir A. Moksel AG, Buchloe, Germany. The tissue surrounding the eyeball was carefully pulled away and the cornea was excised leaving a 2 to 3 mm rim of sclera. The isolated corneas were stored in a petri dish containing HBSS.The corneas were mounted in corneal holders with the endothelial side against the O-ring of the posterior chambe. The anterior chamber was then positioned on top of the cornea and tightened with screws. The chambers of the corneal holder were then filled with RPMI (without phenol red) containing 1% FBS and 2 mM L-glutamine (complete RPMI). The posterior chamber was always filled first. The corneas were incubated for one hour at 32 ± 1 °C.

QUALITY CHECK OF THE ISOLATED CORNEAS: The corneas were visually examined for defects and any defective cornea had been discarded.

NUMBER OF REPLICATES: Triplicate

NEGATIVE CONTROL USED: Yes, physiological saline 0.9% NaCl

SOLVENT CONTROL USED (if applicable): Yes, corn oil

POSITIVE CONTROL USED: Yes, imidazole 20% in physiological saline 0.9% NaCl

APPLICATION DOSE AND EXPOSURE TIME: 750 µL for 4 hours ± 5 minutes incubation at 32 ± 1 °C.

TREATMENT METHOD: closed chamber method

POST-INCUBATION PERIOD: yes, 90 minutes at 32 ± 1 °C

REMOVAL OF TEST SUBSTANCE
- Number of washing steps after exposure period: The test substance or the control substance was removed and the epithelium washed at least three times with MEM
- POST-EXPOSURE INCUBATION: yes, 90 minutes at 32 ± 1 °C

METHODS FOR MEASURED ENDPOINTS:
- Corneal opacity: The following formula was used to calculate the opacity: Opacity= (Io/Iᵦ)/a. The value Io is the illuminance through a holder without cornea, but with windows and liquid. This value is determined by taking the mean for a set of cornea holders and is reevaluated periodically.
- Corneal permeability: passage of sodium fluorescein dye measured with the aid of OD490 using a spectrophotometer
- Others (e.g, pertinent visual observations, histopathology): (please specify)

SCORING SYSTEM: In Vitro Irritancy Score (IVIS)

DECISION CRITERIA: The decision criteria as indicated in the TG was used.

Results and discussion

In vitro

Results

Irritation parameter:

in vitro irritation score

Run / experiment:

bovine corneal opacity and permeability assay

Value:

1.55

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

Other effects / acceptance of results:

OTHER EFFECTS:
- Visible damage on test system: None reported

DEMONSTRATION OF TECHNICAL PROFICIENCY: 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 was considered to be valid.

ACCEPTANCE OF RESULTS:
- Acceptance criteria met for negative control: yes
- Acceptance criteria met for positive control: yes
- Range of historical values if different from the ones specified in the test guideline: not applicable

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

In the in vitro Bovine Corneal Opacity and Permeability Assay, conducted according to an appropriate OECD test guideline and in compliance with GLP, the in vitro irritation score reported for the test substance, octaphenylcyclotetrasiloxane, was < 3. The test substance was concluded to be not irritating to eyes.