Hexane, 1,6-diisocyanato-, homopolymer, 2-hydroxyethyl acrylate- and propylene glycol monoacrylate-blocked

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:

2016

Report date:

2016

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:

Hexane, 1,6-diisocyanato-, homopolymer, 2-hydroxyethyl acrylate- and propylene glycol monoacrylate-blocked

EC Number:

806-984-5

Cas Number:

1392411-89-0

IUPAC Name:

Hexane, 1,6-diisocyanato-, homopolymer, 2-hydroxyethyl acrylate- and propylene glycol monoacrylate-blocked

Test material form:

liquid: viscous

Details on test material:

Name: Ebecryl 4738, Batch no.: DR0004393

Test animals / tissue source

Species:

other: Bos primigenius Taurus

Strain:

not specified

Details on test animals or tissues and environmental conditions:

Fresh bovine eyes were obtained from the slaughterhouse Müller Fleisch GmbH, Enzstr on the day of the test. The cattle were between 12 and 60 months old. The eyes were transported to the test facility in Hank’s Balanced Salt Solution (supplemented with 0.01% streptomycin and 0.01% penicillin). Then, the corneas were dissected and incubated in medium at 32 ± 1°C in an incubation chamber for 1 h.

Test system

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent positive control

yes, concurrent negative control

Amount / concentration applied:

The test substance (pure) was given on the epithelium in such a manner that as much as possible of the cornea was covered with the test substance.

Duration of treatment / exposure:

10 min at 32 ± 1°C

Observation period (in vivo):

-

Duration of post- treatment incubation (in vitro):

2 h at 32 ± 1°C

Number of animals or in vitro replicates:

For each treatment group (negative control solution, test substance and positive control), three replicates were used.

Details on study design:

- The BCOP (The Bovine Corneal Opacity and Permeability) test method is an organotypic model that provides short-term maintenance of normal physiological and biochemical function of the bovine cornea in vitro. In this test method, damage by the test substance is assessed by quantitative measurements of changes in corneal opacity and permeability.
- After the initial incubation, the medium was changed and the baseline opacity for each cornea was recorded. None of the corneas showed tissue damage, therefore, all corneas were used. For each treatment group (negative control solution, test substance and positive control), three replicates were used. After removal of the pre-incubation medium, negative control and positive control solution were applied by pipetting 750 μL of the appropriate liquid through the refill hole in the holder on the cornea. In order to apply the test substance, the nut was unscrewed to remove the glass disc. Then, the test substance was applied on the epithelium in such a manner that as much as possible of the cornea was covered with the test substance. Exposure time on the corneas was 10 min at 32 ± 1°C. After thorough rinsing with cMEM with phenol red and final rinsing with cMEM without phenol red, the anterior chamber was filled with cMEM without phenol red, and the corneas were stored for additional 2 h at 32 ± 1°C (post-incubation). After the post-incubation, the cMEM without phenol red was renewed in both chambers. Then, the final opacity value of each cornea was recorded. The cMEM without phenol red was removed from the front chamber, and 1 mL sodium fluorescein solution (concentration: 4 mg/mL) was added to the front chamber. The chambers were closed again and incubated for 85 min at 32 ± 1°C. After incubation, the content of the posterior chamber was thoroughly mixed. Finally, the corneal permeability was measured with the spectral photometer at 492 nm.

Results and discussion

In vitro

Results

Irritation parameter:

in vitro irritation score

Remarks:

corneal opacity and permeability

Run / experiment:

BCOP test

Value:

4.41

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Other effects / acceptance of results:

In the negative control, no signs of eye irritation were observed. The positive control induced serious eye damage. The test substance showed effects on the cornea of the bovine eye. The calculated IVIS (in vitro irritancy score) was 4.41. The experiment is considered as sufficient for a reliable calculation of the IVIS of the test substance, because all three replicates of the test substance led to the same assessment for the test substance (IVIS for each replicate of the test substance: 5.70; 3.25; 4.28; Mean IVIS: 4.41; Relative Standard Deviation IVIS: 27.98%).

Applicant's summary and conclusion

Interpretation of results:

study cannot be used for classification

Conclusions:

Under the study conditions, no prediction for eye irritation can be made.

Executive summary:

A study was conducted to determine the eye irritation potential of the test substance according to OECD Guideline 437 (Bovine Corneal Opacity and Permeability test method), in compliance with GLP. Bovine corneas were collected from cattle. One valid experiment was performed with three replicates each for the negative control, the positive control (dimethyl formamide) and the test substance. The pure, undiluted test substance was applied for 10 min at 32°C in a way that as much as possible of the cornea surface was covered. After removal of the test substance and a 2 h post-incubation, opacity and permeability values were measured to give the in vitro irritation score (IVIS). The IVIS for the test substance was determined to be 4.41 (i.e. between > 3 and ≤ 55). No signs of eye irritation were observed following exposure with the negative control. The positive control induced serious eye damage. Both the controls met the validity criteria. Under the study conditions, the test substance produced a in vitro irritancy score of 4.41 and therefore, according to OECD Guideline 437 criteria, no prediction for eye irritation can be made (Andres, 2017).