Hexamethylene diisocyanate, trimers, reaction products with 2-hydroxyethyl acrylate

Skin irritation / corrosion

Administrative data

Endpoint:

skin corrosion: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

30 Mar - 01 Apr 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:

OECD Guideline 431 (In Vitro Skin Corrosion: Reconstructed Human Epidermis (RHE) Test Method)

Version / remarks:

adopted in 2015

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: EU Method B.40 BIS (In Vitro Skin Corrosion: Human Skin Model Test)

Version / remarks:

adopted in 2008

Test guideline 3

Qualifier:

according to guideline

Guideline:

other: ECVAM INVITTOX Protocol No 118: "EpiSkinTM Skin Corrosivity Test"

Version / remarks:

adopted in 2011

GLP compliance:

yes (incl. QA statement)

Remarks:

Bayerisches Landesamt für Gesundheit und Lebensmittelsicherheit, Schwabach, Germany

Test material

Test material information

Constituent 1

Reference substance name:

Hexamethylene diisocyanate, trimers, reaction products with 2-hydroxyethyl acrylate

EC Number:

500-734-6

EC Name:

Hexamethylene diisocyanate, trimers, reaction products with 2-hydroxyethyl acrylate

Cas Number:

162492-01-5

Molecular formula:

C39 H60 N6 O15

IUPAC Name:

Hexamethylene diisocyanate, trimers, reaction products with 2-hydroxyethyl acrylate

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

other: normal human epidermal keratinocytes (NHEK)

Source strain:

other: reconstructed three-dimensional human epidermis model (SkinEthic)

Justification for test system used:

This test uses the EPISKIN-SMTM reconstructed human epidermis model (SkinEthic) which consists of normal human epidermal keratinocytes (NHEK) and therefore represents in vitro the target organ of the species of interest and closely mimics the biochemical and physiological properties of the upper parts of the human skin, i.e. the epidermis. This method allows the identification of corrosive and non-corrosive substances and mixtures in accordance with UN GHS. It further allows a partial sub-caregorisation of corrosives in optional sub-category 1A or a combination of optional sub-categories 1B and 1C.

Vehicle:

unchanged (no vehicle)

Details on test system:

RECONSTRUCTED HUMAN EPIDERMIS (RHE) TISSUE
- Model used: reconstituted three-dimensional human skin model EPISKIN-SMTM (SkinEthic) consisting of normal human epidermal keratinocytes
- Tissue batch number: 16-EKIN-013

TEMPERATURE USED FOR TEST SYSTEM
- Temperature used during treatment / exposure: room temperature
- Temperature of post-treatment incubation: 37 ± 1°C

REMOVAL OF TEST MATERIAL AND CONTROLS
-Volume and number of washing steps: 25 mL, about 15 times

MTT DYE USED TO MEASURE TISSUE VIABILITY AFTER TREATMENT / EXPOSURE
- MTT concentration: 0.3 mg/mL
- Incubation time: 3 h ± 15 min
- Spectrophotometer: plate spectrophotometer
- Wavelength: 570 nm

FUNCTIONAL MODEL CONDITIONS WITH REFERENCE TO HISTORICAL DATA
For historical control data see table 1.

NUMBER OF REPLICATE TISSUES: 2

NUMBER OF INDEPENDENT TEST SEQUENCES / EXPERIMENTS TO DERIVE FINAL PREDICTION: 1

PREDICTION MODEL / DECISION CRITERIA (choose relevant statement)
- The test substance is considered to be corrosive to skin in accordance with Regulation EC 1272/2008 and UN GHS "Category 1" if the relative tissue viability after 4 h treatment is decreased below 35%: if viability is reduced to less than 35% after 4 h treatment and to more than 35% after 60 min treatment or to less than 35% viability after 60 min but not more than 35% after 3 min treatment, the test item is classified as corrosive, in accordance with optional UN GHS sub-categories 1B and 1C. A test item which decreases viability below 35% after 3 min treatment is classified as corrosive in accordance with optional UN GHS sub-category 1A.
- The test substance may be considered as non-corrosive to skin in accordance with UN GHS "No Category" if realtive tissue viability after 4 h treatment is not decreased to less than 35% of the corresponding negative control tissues.

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 50 ± 2 mg

NEGATIVE CONTROL
- Amount(s) applied (volume or weight): 50 µL
- Concentration (if solution): 0.9%

POSITIVE CONTROL
- Amount(s) applied (volume or weight): 50 µL
- Concentration (if solution): 100%

Duration of treatment / exposure:

4 h, 60 min and 3 min

Duration of post-treatment incubation (if applicable):

Not applicable

Number of replicates:

2

Results and discussion

In vitro

Results

Results 1

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

3 min

Value:

59

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

not examined

Remarks on result:

other: no indication of corrosion

Results 2

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

60 min

Value:

102

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

not examined

Remarks on result:

other: no indication of corrosion

Results 3

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

4 h

Value:

58

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Remarks:

2% tissue viability

Remarks on result:

other: no indication of corrosion

Other effects / acceptance of results:

- OTHER EFFECTS:
- Direct-MTT reduction: A mixture of 20 mg test item per 2 mL MTT medium showed no reduction of MTT as compared to the solvent. The mixture did not turn purple/blue. Therefore, the non-specific reduction of MTT equaled 0%.
- Colour interference with MTT: A mixture of 10 mg of the test item per 90 µL aqua dest. and per 90 µL isopropanol showed no colouring as compared to the solvent. Therefore, non-specific colour of additional viable tissues equaled 0%.

DEMONSTRATION OF TECHNICAL PROFICIENCY: The controls confirmed the validity of the study.

ACCEPTANCE OF RESULTS:
- Acceptance criteria met for negative control: yes
- Acceptance criteria met for positive control: yes
- Acceptance criteria met for variability between replicate measurements: yes
- Range of historical values if different from the ones specified in the test guideline: See table 1 for historical control data.

Applicant's summary and conclusion

Interpretation of results:

other: CLP/GHS criteria not met; no classification required according to Regulation (EC) No. 1272/208

Conclusions:

CLP: not classified