Hexamethylene diisocyanate, oligomers, reaction products with Bis-(Trimethoxysilylpropyl)amine

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Jan 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 492 (Reconstructed Human Cornea-like Epithelium (RhCE) Test Method for Identifying Chemicals Not Requiring Classification and Labelling for Eye Irritation or Serious Eye Damage)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

1-{6-[3,5-bis(6-isocyanatohexyl)-2,4,6-trioxo-1,3,5-triazinan-1-yl]hexyl}-3,3-bis[3-(trimethoxysilyl)propyl]urea

EC Number:

918-105-3

IUPAC Name:

1-{6-[3,5-bis(6-isocyanatohexyl)-2,4,6-trioxo-1,3,5-triazinan-1-yl]hexyl}-3,3-bis[3-(trimethoxysilyl)propyl]urea

Test material form:

liquid: viscous

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: 17/0241-1, Batch 294-296

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: room temperature

Test animals / tissue source

Species:

human

Strain:

not specified

Details on test animals or tissues and environmental conditions:

TEST SYSTEM
- Source: MatTek In Vitro Life Science Laboratories, Bratislava, Slovakia
- Tissue model: OCL-200
- Tissue Lot Number: 27004 and 27009
- Incubation conditions: 37°C +/- 1°C, 5% +/- 1% CO2, 90% +/- 5% relative humidity
- Detection agent: MTT
- Ectracting agent: Isopropanol
- Wash buffer: PBS

Test system

Vehicle:

unchanged (no vehicle)

Controls:

yes

Details on study design:

- Negative control: Deionized water, sterile
- Positive control: Neat methyl acetate

Results and discussion

In vitro

Results

Results 1

Irritation parameter:

other: tissue viability (% of NC)

Run / experiment:

Mean 1st Run

Value:

130.5

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

no indication of irritation

Results 2

Irritation parameter:

other: tissue viability (% of NC)

Run / experiment:

Mean of 2nd Run

Value:

95

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

no indication of irritation

Other effects / acceptance of results:

ACCEPTANCE OF RESULTS:
- Acceptance criteria met for negative control: yes
- Acceptance criteria met for positive control: yes

Any other information on results incl. tables

1st Run: Individual and mean OD570 values, individual and mean viability values and inter-tissue variability

Test substance		Tissue 1	Tissue 2	Mean	Inter-tissue variability (%)
NC	Mean OD570	0.814	0.788	0.801
NC	Viability (% of NC)	101.6	98.4	100.0	3.2
Test item	Mean OD570	0.842	1.249	1.045
Test item	Viability (% of NC)	105.1	155.9	130.5	50.8
PC	Mean OD570	0.255	0.215	0.235
PC	Viability (% of NC)	31.8	26.8	29.3	5.1

2nd Run: Individual and mean OD570 values, individual and mean viability values and inter-tissue variability

Test substance		Tissue 1	Tissue 2	Mean	Inter-tissue variability (%)
NC	Mean OD570	1.594	1.727	1.660
NC	Viability (% of NC)	96.0	104.0	100.0	8.0
Test item	Mean OD570	1.540	1.616	1.578
Test item	Viability (% of NC)	92.7	97.3	95.0	4.6
PC	Mean OD570	0.445	0.325	0.385
PC	Viability (% of NC)	26.8	19.6	23.2	7.2

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Based on the results observed for the EpiOcular Test alone and by applying the evaluation criteria it was concluded that the test item does not show an eye irritation potential in the in vitro eye irritation test strategy under the test conditions chosen.

Executive summary:

The objective was to assess the eye irritating potential of the test item. By using the methods currently available a single in vitro assay is not sufficient to cover the full range of eye irritating potential. Therefore, two in vitro assays were part of this in vitro eye irritation test strategy: The Bovine Corneal Opacity and Permeability Test (BCOP Test) and EpiOcular Eye Irritation Test. However, in the current case the results derived with EpiOcular Eye Irritation Test alone were sufficient for a final assessment. Therefore, further testing in BCOPwas waived.

EpiOcular Eye Irritation Test

The potential of the test substance to cause ocular irritation was assessed by a single topical application of 50 μL undiluted test substance to a reconstructed three-dimensional, human cornea model (EpiOcular™). Two test runs were performed. Two EpiOcular™ tissues per test run were incubated with the test substance for 30 minutes followed by a 2-hour post-incubation period. Tissue destruction was determined by measuring the metabolic activity of the tissue after exposure/post-incubation by using a colorimetric test. The reduction of mitochondrial dehydrogenase activity measured by reduced formazan production after incubation with a tetrazolium salt (MTT) was chosen as endpoint. The formazan production of the epidermal tissues treated with the test substance is compared to that of negative control tissues. The ratio

of the values indicates the relative tissue viability. The test substance is not able to directly reduce MTT.

As the acceptance criterion for inter-tissue variability of the test substance was not met (values for single tissues: 105.1% and 155.9%) and the mean OD570 of the NC was exceptionally low (0.801), a 2nd experiment was performed to clarify the result. In the 2nd test run, the mean viability of the tissues treated with the test substance was 95.0%. All acceptance criteria were met. Minimal compound residues remained on the tissues treated with the test substance after the washing procedure of both test runs.

Based on the results observed in the EpiOcular Test alone and by applying the evaluation, it was concluded that the test substance does not show an eye irritation potential in the in vitro eye irritation test strategy under the test conditions chosen.