4,4'-isopropylidenediphenyl dicyanate

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

February - March 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2016

Report date:

2016

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EU method B.48 (Isolated chicken eye test method for identifying occular corrosives and severe irritants)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 438 (Isolated Chicken Eye 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:

4,4'-isopropylidenediphenyl dicyanate

EC Number:

214-590-4

EC Name:

4,4'-isopropylidenediphenyl dicyanate

Cas Number:

1156-51-0

Molecular formula:

C17H14N2O2

IUPAC Name:

4-{2-[4-(cyanooxy)phenyl]propan-2-yl}phenyl cyanate

Test material form:

other: flaked solidified melt

Details on test material:

- Physical state: see above
- Appearance: see above

Specific details on test material used for the study:

- Test Substance Name: LZ 514
- Source: Lonza Ltd, Visp/Switzerland
- Lot/batch No. of test material: 5011
- Expiration date of the lot/batch: 2nd December 2017
- Manufacture date: 3rd December 2015

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage conditions: Controlled room temperature (15-25 ºC, below 70 RH%), protected from light and humidity.
- Stability under test conditions: stable
- Safety precautions: Routine safety precautions (lab coat, gloves, safety glasses, face mask) for unknown materials were applied to assure personnel health and safety.

Test animals / tissue source

Species:

chicken

Strain:

other: ROSS 308

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): 30 mg test item

NEGATIVE CONTROL
- Amount(s) applied (volume or weight): 30 mg Imidazole

POSITIVE CONTROL
- Amount(s) applied (volume or weight): 30 μL physiological saline

Duration of treatment / exposure:

10 seconds

Observation period (in vivo):

not applicable

Duration of post- treatment incubation (in vitro):

none

Number of animals or in vitro replicates:

Three test item treated eyes, three positive control treated eyes and one negative control treated eye were examined.

Details on study design:

SELECTION AND PREPARATION OF ISOLATED EYES
- Tissue: chicken eyes from chicken heads; chicken heads collected after slaughter in a commercial abattoir from chickens (approximately 7 weeks old)
- Source: TARAVIS KFT (Address: 9600 Sárvár, Rábasömjéni út. 129., Hungary)
- Preparation:After removing the head from the plastic box, it was put on soft paper. The eyelids were carefully cut away with scissors, avoiding damaging the cornea. One small drop of 2% (w/v) fluorescein solution was applied onto the cornea surface for a few seconds and subsequently rinsed off with 20 mL physiological saline. Then the fluorescein-treated cornea was examined with a hand-held slit lamp or slit lamp microscope, with the eye in the head, to ensure that the cornea was not damaged. If the cornea was in good condition, the eyeball was carefully removed from the orbit by holding the nictitating membrane with a surgical forceps, while cutting the eye muscles with bent scissors. Care was taken to remove the eyeball from the orbit without cutting off the optical nerve too short. The procedure avoided pressure on the eye while removing the eyeball from the orbit, in order to prevent distortion of the cornea and subsequent corneal opacity. Once removed from the orbit, the eye was placed onto damp paper and the nictitating membrane was cut away with other connective tissue. The prepared eyes were kept on the wet papers in a closed box so that the appropriate humidity was maintained.

ENVIRONMENTAL CONDITIONS
If the selected eyes were appropriate for the test, acclimatization started and it was conducted for approximately 45 to 60 minutes. The chambers of the superfusion apparatus were at controlled temperature (32±1.5°C) during the acclimatization and treatment periods.

NUMBER OF REPLICATES
In the study, three test item treated eyes, three positive control treated eyes and one negative control treated eye were examined.

NEGATIVE CONTROL USED
Physiological saline (Salsol solution, 0.9% (w/v) NaCl)

POSITIVE CONTROL USED
Imidazole

APPLICATION DOSE AND EXPOSURE TIME
30 mg test item applied for 10 seconds

OBSERVATION PERIOD
30, 75, 120, 180 and 240 minutes after the post-treatment rinse

REMOVAL OF TEST SUBSTANCE
Volume and washing procedure after exposure period: rinsed thoroughly with 20 mL physiological saline solution at ambient temperature

METHODS FOR MEASURED ENDPOINTS:
Corneal thickness and corneal opacity were measured at all time points. Fluorescein retention was measured on two occasions, at baseline (t=0) and approximately 30 minutes after the post-treatment rinse. Haag-Streit Bern 900 slit-lamp microscope was used for the measurements.

Results and discussion

In vitro

Results

Results 1

Irritation parameter:

cornea opacity score

Run / experiment:

three test item treated eyes, three positive control treated eyes and one negative control treated eye examined

Value:

0.5 - 1

Vehicle controls validity:

not examined

Negative controls validity:

valid

Positive controls validity:

valid

Results 2

Irritation parameter:

fluorescein retention score

Run / experiment:

three test item treated eyes, three positive control treated eyes and one negative control treated eye were examined

Value:

0.5 - 1

Vehicle controls validity:

not examined

Negative controls validity:

valid

Positive controls validity:

valid

Results 3

Irritation parameter:

percent corneal swelling

Run / experiment:

three test item treated eyes, three positive control treated eyes and one negative control treated eye were examined

Value:

0

Vehicle controls validity:

not examined

Negative controls validity:

valid

Positive controls validity:

valid

Other effects / acceptance of results:

The cornea surfaces were not cleared at 240 minutes after the post-treatment rinse. This fact might indicate morphological changes in an in vivo system (although during in vivo conditions the eyelids will probably clear the surface, but abrasion may occur).

In vivo

Irritant / corrosive response data:

no irritation observed

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Based on these in vitro eye irritation assay in isolated chicken eyes, the test item is not classified as a severe irritant and not classified as non-irritant. It is concluded that further information is required for classification.

Executive summary:

An in vitro eye irritation test was performed in a in isolated chicken’s eyes. The irritation effects of the test item were evaluated according to the OECD No. 438 guideline (26 July 2013).

No corneal swelling was observed during the four-hour observation period on test item treated eyes. Slight corneal opacity change (severity 0.5 or 1) was observed in all three eyes. Slight fluorescein retention change (severity 0.5 or 1) was noted on all three eyes. However, the cornea surfaces were not cleared at 240 minutes after the post-treatment rinse. This fact might indicate morphological changes in an in vivo system (although during in vivo conditions the eyelids will probably clear the surface, but abrasion may occur). Based on these in vitro eye irritation assays in isolated chicken eyes, the test item is not classified as a severe irritant and not classified as non-irritant. It is concluded that further information is required for classification.