2-(3,7-dimethylocta-2,6-dienyl)cyclopentan-1-one

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

January 28 - August 1, 2019

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2019

Report date:

2019

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)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

2-(3,7-dimethylocta-2,6-dienyl)cyclopentan-1-one

EC Number:

268-706-3

EC Name:

2-(3,7-dimethylocta-2,6-dienyl)cyclopentan-1-one

Cas Number:

68133-79-9

Molecular formula:

C15H24O

IUPAC Name:

2-(3,7-dimethylocta-2,6-dienyl)cyclopentan-1-one

Test animals / tissue source

Species:

cattle

Details on test animals or tissues and environmental conditions:

SOURCE OF COLLECTED EYES
- Source: abattoir A. Moksel AG, Buchloe, Germany
- Storage, temperature and transport conditions of ocular tissue (e.g. transport time, transport media and temperature, and other conditions): Eyes were transported on ice with antibiotics.
- Time interval prior to initiating testing: Eyes were prepared immediately after arrival.
- indication of any existing defects or lesions in ocular tissue samples: Eyes were examined for defects, and any eyes with defects were discarded.
- Indication of any antibiotics used: Penicillin and streptomycin

Test system

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent positive control

yes, concurrent negative control

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 750 uL
- Concentration (if solution): 100%

Duration of treatment / exposure:

10 minutes

Duration of post- treatment incubation (in vitro):

3.5 hrs

Number of animals or in vitro replicates:

3

Details on study design:

SELECTION AND PREPARATION OF CORNEAS
Tissue around the eyeball was carefully pulled away. Cornea was excised to 2-3 mm rim of sclera. These were then stored in petri dishes containing HBSS. They were then mounted in corneal holders. The corneal holders were filled with RPMI 1640 medium without phenol red, but with 1% FBS and 2 mM L-glutamine. Posterior chambers were filled first. Corneas were then incubated for 1 hr at 32 degrees C.

QUALITY CHECK OF THE ISOLATED CORNEAS
Yes

NUMBER OF REPLICATES
3

NEGATIVE CONTROL USED
Physiological saline solution (0.9% NaCl)

POSITIVE CONTROL USED
100% ethanol

APPLICATION DOSE AND EXPOSURE TIME
750 uL for 10 minutes

POST-INCUBATION PERIOD: yes, 3.5 hrs

REMOVAL OF TEST SUBSTANCE
- Number of washing steps after exposure period: 3 times
- POST-EXPOSURE INCUBATION: 3.5 hrs, with illuminance measurement after 2 hrs, new medium introduced, and then additional incubation for 90 minutes and the optical density measured.

METHODS FOR MEASURED ENDPOINTS:
- Corneal opacity: Illuminance, optical density
- Corneal permeability: passage of sodium fluorescein dye measured with the aid of UV/VIS spectrophotometry
- Others (e.g, pertinent visual observations, histopathology): histopathology

SCORING SYSTEM: In Vitro Irritancy Score (IVIS)

DECISION CRITERIA: IVIS =< 3, no category
IVIS >3, =< 55, No prediction can be made
IVIS > 55, cateogry 1

Results and discussion

In vitro

Results

Results 1

Irritation parameter:

in vitro irritation score

Run / experiment:

7

Value:

2.52

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Results 2

Irritation parameter:

in vitro irritation score

Run / experiment:

8

Value:

1.15

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Results 3

Irritation parameter:

in vitro irritation score

Run / experiment:

9

Value:

1.42

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Results 4

Irritation parameter:

in vitro irritation score

Run / experiment:

Average

Value:

1.77

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Other effects / acceptance of results:

OTHER EFFECTS:
- Visible damage on test system:

DEMONSTRATION OF TECHNICAL PROFICIENCY:

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:

Any other information on results incl. tables

Histopathology showed at most mild irritation.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The mean in vitro irritation score was 1.77. By UN GHS guidelines, the substance is not categorized as an eye irritant.

Executive summary:

The eye irritancy potential of apritone was tested in an OECD guideline 437 Bovine Corneal Opacity and Permeability Assay. Three fresh bovine eyes were exposed to 750 uL of the test substance for 10 minutes. The eyes were then washed, and the optical density was determined after 3.5 hrs of incubation. Physiological saline was used as a negative control, and 100% ethanol was used as a positive control. Negative and positive control results were valid. The mean in vitro irritation score was determined to be 1.77. By UN GHS guidelines, the substance is not categorized as an eye irritant.