Ethyl nicotinate

Skin irritation / corrosion

Administrative data

Endpoint:

skin corrosion: 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 431 (In Vitro Skin Corrosion: Reconstructed Human Epidermis (RHE) Test Method)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Ethyl nicotinate

EC Number:

210-370-7

EC Name:

Ethyl nicotinate

Cas Number:

614-18-6

Molecular formula:

C8H9NO2

IUPAC Name:

ethyl nicotinate

Test material form:

liquid

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

non-transformed keratinocytes

Cell source:

foreskin from multiple donors

Source strain:

not specified

Details on animal used as source of test system:

EpiDerm™ Reconstructed Human Epidermis Model Kit
Supplier : MatTek
Date received : 15 September 2015
EpiDermTM Tissues (0.63cm
2
) lot number : 21695
Assay Medium lot number : 091015TMA
Upon receipt of the EpidermTM tissues, the sealed 24-well plate was stored in a refrigerator until
use.

Details on test system:

RECONSTRUCTED HUMAN EPIDERMIS (RHE) TISSUE
- Model used: MAttek EpiDerm
- Tissue batch number(s): 21695
- Production date:
- Shipping date:
- Delivery date: 15 Sept 2015
- Date of initiation of testing: 15 sept 2015

TEMPERATURE USED FOR TEST SYSTEM
- Temperature used during treatment / exposure: 37 celsius
- Temperature of post-treatment incubation (if applicable): 37 cesius

REMOVAL OF TEST MATERIAL AND CONTROLS
-Volume and number of washing steps: Rinsing was achieved by filling and
emptying each tissue under a constant soft stream of DPBS to gently remove any residual test
item. Excess DPBS was removed by blotting the bottom of the tissue insert with tissue paper.
- Observable damage in the tissue due to washing: not reported
- Modifications to validated SOP: none noted

MTT DYE USED TO MEASURE TISSUE VIABILITY AFTER TREATMENT / EXPOSURE
- MTT concentration: 1.0 mg/mL MTT solution.
- Incubation time: 3 hours
- Spectrophotometer: Anthos 2001 microplate
reader
- Wavelength: 562nm
- Filter: not reported
- Filter bandwidth: not reported
- Linear OD range of spectrophotometer: not reported

FUNCTIONAL MODEL CONDITIONS WITH REFERENCE TO HISTORICAL DATA
- Viability:
- Barrier function:
- Morphology:
- Contamination:
- Reproducibility:

NUMBER OF REPLICATE TISSUES: 3

CONTROL TISSUES USED IN CASE OF MTT DIRECT INTERFERENCE - Not applicable

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

PREDICTION MODEL / DECISION CRITERIA
- The test substance is considered to be corrosive to skin if [complete, e.g. the viability after 3 minutes exposure is less than 50%, or if the viability after 3 minutes exposure is greater than or equal to 50 % and the viability after 1 hour exposure is less than 15%.]

Control samples:

yes, concurrent negative control

yes, concurrent positive control

yes, concurrent MTT non-specific colour control

Amount/concentration applied:

50 µL (microlitres)

Duration of treatment / exposure:

3 minutes and 60 minutes

Duration of post-treatment incubation (if applicable):

Not Applicable

Number of replicates:

three

Results and discussion

In vitro

Results

Results 1

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

3 minutes

Value:

ca. 90.5

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Results 2

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

60 minutes

Value:

ca. 9

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

positive indication of irritation

Other effects / acceptance of results:

3.7 Quality Criteria
The results of the assay are considered acceptable if the following assay acceptance criteria are
achieved:
Negative Control:
The absolute OD562 of the negative control treated tissues in the MTT-test is an indicator of
tissue viability obtained in the testing laboratory after the shipping and storing procedure and
under specific conditions of the assay. The mean OD562 of the two negative control tissues
should be ≥ 0.8 and ≤ 2.8 for each exposure time, which ensures that the tissue viability meets
the acceptance criteria.
Positive Control:
Potassium Hydroxide 8.0N solution is used as a positive control. An assay meets the acceptance
criterion if mean relative tissue viability of the 60 minute positive control is < 15%.
Coefficient of Variation:
In the range 20 and 100% viability, the Coefficient of Variation between tissue replicates should
be ≤ 30%.

Any other information on results incl. tables

4.5 Quality Criteria

The mean OD562 for the negative control treated tissues was 2.078 for the 3-Minute exposure period and 2.159 for the 60-Minute exposure period. The negative control acceptance criteria were therefore satisfied.

The relative mean tissue viability for the positive control treated tissues was 3.8% relative to the negative control following the 60-Minute exposure period. The positive control acceptance criterion was therefore satisfied.

In the range 20 to 100% viability the Coefficient of Variation between the two tissue replicates of each treatment group did not exceed 30%. The acceptance criterion was therefore satisfied.

Applicant's summary and conclusion

Interpretation of results:

Category 1B (corrosive) based on GHS criteria

Conclusions:

The test item was classified as corrosive to the skin. The following classification criteria apply:
EU CLP and UN GHS: Hazard statement H314 Category 1B or 1C.
UN Packing Group II or III.