Fatty acids, C18-36, esters with ethylene glycol

Skin irritation / corrosion

Administrative data

Endpoint:

skin corrosion: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

11 October 2017 to 13 October 2017

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

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

2016

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: Method B.40bis of Commission Regulation (EC) No 440/2008, of 30 May 2008,

Version / remarks:

laying down test methods pursuant to Regulation (EC) No 1907/2006 of the European Parliament and of the Council on the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Fatty acids, C18-36, esters with ethylene glycol

EC Number:

305-673-7

EC Name:

Fatty acids, C18-36, esters with ethylene glycol

Cas Number:

94944-95-3

Molecular formula:

C40H78O4/C70H138O4

IUPAC Name:

Fatty acids, C18-36, esters with ethylene glycol

Test material form:

solid

Specific details on test material used for the study:

the test substance was ground into a powder before application

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

other: EpiDerm™ Human Skin Mode

Cell source:

other: EpiDerm™ Human Skin Mode

Vehicle:

unchanged (no vehicle)

Details on test system:

RECONSTRUCTED HUMAN EPIDERMIS (RHE) TISSUE
- Model used: EpiDerm™ Human Skin Mode (MatTek)
- Tissue batch number(s): 25848
- Delivery date: 10 Octobert 2017

TEMPERATURE USED FOR TEST SYSTEM
- Temperature used during treatment / exposure: 37 ˚C, 5% CO2
- Temperature of post-treatment incubation (if applicable): 37 ˚C, 5% CO2

REMOVAL OF TEST MATERIAL AND CONTROLS: rinsed under a constant soft stream of DPBS and blotted dry with a tissue

MTT DYE USED TO MEASURE TISSUE VIABILITY AFTER TREATMENT / EXPOSURE
- MTT concentration: 1.0 mg/mL MTT
- Incubation time: 3 h
- Spectrophotometer: Labtech LT-4500 microplate reader
- Wavelength: 570 nM

NUMBER OF REPLICATE TISSUES: 2/treatment

TISSUES:
- Fresh tissues: for treatment, negative control and positive control

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

PREDICTION MODEL / DECISION CRITERIA (choose relevant statement)
- The test substance is considered to be corrosive to skin if [complete, e.g. the viability after 3 minutes exposure is less than 50% (H314 1A), 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% (H314 1B or 1C)
- The test substance is considered to be non-corrosive to skin if [complete, e.g. the viability after 3 minutes exposure is greater than or equal to 50% and the viability after 1 hour exposure is greater than or equal to 15% (not classified as corrosive)
:

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 25 mg as such (tissues wetted with 25 µL sterile water)

NEGATIVE CONTROL
- Amount(s) applied (volume or weight with unit): 50 µL distilled water

POSITIVE CONTROL
- Amount(s) applied (volume or weight): 50 µL 8.0 N Potassium Hydroxide

Duration of treatment / exposure:

3 min and 60 min

Duration of post-treatment incubation (if applicable):

The plates was incubated (37 ˚C, 5% CO2) for 3 hours in presence of MTT. Thereafter tissues were placed in isopropanol for MTT extraction, which was measured in triplicate samples as optical density at 570 nm.

Number of replicates:

2/treatment

Results and discussion

In vitro

Results

Results 1

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

A 3 minutes exposure

Value:

97.1

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

other: non-corrosive

Results 2

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

B 60 minutes exposure

Value:

102.4

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

other: non-corrosive

Other effects / acceptance of results:

The results were in agreement with the quality criteria:

Negative Control
The absolute OD570 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 OD 570 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

 

	Exposure time	Mean OD570	Relative mean viability
Negative control	3 min	1.408	100%
	60 min	1.382	100%
Test substance	3 min	1.367	97.1%
	60 min	1.415	102.4%
Positive control	3 min	0.044	3.1%
	60 min	0.045	3.3%

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The substance is considered non-corrosive

Executive summary:

The substance was tested in the EpiDerm™ Human Skin Model using duplicate tissues during 3 and 60 minutes. The relative mean viability of the test substance treated tissues was 97.1 % for the 3 minutes exposure and 102.4% for the 60 minutes exposure. Therefore it can be concluded that the substance is not corrosive to the skin.