Decyl 2-ethylhexanoate

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

25 July - 01 Aug 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

/ No demonstration of technical proficiency

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 439 (In Vitro Skin Irritation: Reconstructed Human Epidermis Test Method)

Version / remarks:

28 July 2015

Deviations:

yes

Remarks:

/ No demonstration of technical proficiency

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.46 (In Vitro Skin Irritation: Reconstructed Human Epidermis Model Test)

Version / remarks:

06 July 2012

Deviations:

yes

Remarks:

/ No demonstration of technical proficiency

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Decyl 2-ethylhexanoate

EC Number:

298-078-6

EC Name:

Decyl 2-ethylhexanoate

Cas Number:

93777-46-9

Molecular formula:

C18H36O2

IUPAC Name:

decyl 2-ethylhexanoate

Test material form:

liquid

Specific details on test material used for the study:

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

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

non-transformed keratinocytes

Cell source:

other: Adult donors

Source strain:

other: EPISKIN Small Model™ (EPISKIN-SM™, 0.38 cm2, 09-KERA-009, 11-KERA-002, 08-KERA-001, 10-KERA-005)

Details on animal used as source of test system:

- Source: SkinEthic Laboratories, Lyon, France

Justification for test system used:

In the interest of sound science and animal welfare, a sequential testing strategy is recommended to minimise the need of in vivo testing. One of the validated in vitro skin irritation tests is the EPISKIN test, which is recommended in international guidelines (e.g. OECD and EC)

Vehicle:

unchanged (no vehicle)

Details on test system:

RECONSTRUCTED HUMAN EPIDERMIS (RHE) TISSUE
- Model used: EPISKIN Small Model™ (EPISKIN-SM™, 0.38 cm², 09-KERA-009, 11-KERA-002, 08-KERA-001, 10-KERA-005 )
- Tissue batch number(s): 16-EKIN-030
- Date of initiation of testing: 25 July 2016

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

REMOVAL OF TEST MATERIAL AND CONTROLS
- Volume and number of washing steps: one washing step
- Observable damage in the tissue due to washing: no

MTT DYE USED TO MEASURE TISSUE VIABILITY AFTER TREATMENT / EXPOSURE
- MTT concentration: 0.3 mg/mL in PBS
- Incubation time: 3 h
- Spectrophotometer: TECAN Infinite® M200 Pro Plate Reader
- Wavelength: 570 nm

FUNCTIONAL MODEL CONDITIONS WITH REFERENCE TO HISTORICAL DATA
- Viability:
Negative control (OD 570): 1.06 ± 0.14
Positive control (OD 570): 0.16 ± 0.11
Positive control (viability %): 14.78 ± 9.29

- Barrier function: tested and acceptable
- Morphology: tested and acceptable
- Contamination: negative
- Reproducibility: no information

NUMBER OF REPLICATE TISSUES: 3

NUMBER OF INDEPENDENT TEST SEQUENCES / EXPERIMENTS TO DERIVE FINAL PREDICTION: 3

PREDICTION MODEL / DECISION CRITERIA
A test item is considered irritant or corrosive in the skin irritation test if:
The relative mean tissue viability of three individual tissues after 15 minutes of exposure to the test item and 42 hours of post incubation is ≤ 50% of the mean viability of the negative controls.
A test item is considered non-irritant in the in vitro skin irritation test if:
The relative mean tissue viability of three individual tissues after 15 minutes of exposure to the test item and 42 hours of post incubation is > 50% of the mean viability of the negative controls.

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

TEST MATERIAL
- Amount(s) applied: 25 μL
- Concentration (if solution): neat/ undiluted

NEGATIVE CONTROL
- Amount(s) applied (volume or weight): 25 μL
- Concentration (if solution): neat/ undiluted

POSITIVE CONTROL
- Amount(s) applied (volume or weight): 25 μL
- Concentration (if solution): 5% in PBS

Duration of treatment / exposure:

15 ± 0.5 min at room temperature

Duration of post-treatment incubation (if applicable):

42 h at 37° C

Number of replicates:

3

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

mean value of test item (neat/ undiluted)

Value:

ca. 102

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Other effects / acceptance of results:

- OTHER EFFECTS:
- Visible damage on test system: no
- Direct-MTT reduction: no
- Colour interference with MTT: no

DEMONSTRATION OF TECHNICAL PROFICIENCY: no

ACCEPTANCE OF RESULTS:
- Acceptance criteria met for negative control: The absolute mean OD570 (optical density at 570 nm) of the three tissues should be within the laboratory historical control data range and the Standard Deviation value (SD) of the % viability should be ≤18.
- Acceptance criteria met for positive control: The mean relative tissue viability should be ≤ 50% relative to the negative control and the Standard Deviation value (SD) of the % viability should be ≤18.
- Acceptance criteria met for variability between replicate measurements: the Standard Deviation value (SD) of the % viability should be ≤18.

Any other information on results incl. tables

Table 1: MTT assay (15 ± 0.5 min exposure)

	Tissue No.	OD570*	Mean (OD570)	Standard Deviation	Mean tissue viability (% of negative control)	Standard Deviation [%]
Negative Control	1	1.151	0.999	0.160	100	16
	2	1.015
	3	0.833
Positive Control	1	0.103	0.161	0.093	16	9
	2	0.269
	3	0.112
Test Item	1	0.899	1.015	0.185	102	19
	2	1.228
	3	0.918

OD = optical density

SD = Standard deviation

 

* The values represent the mean values of two OD₅₇₀ measurements per well and are corrected for background absorption (0.042).

Isopropanol was used to measure the background absorption.

Applicant's summary and conclusion

Interpretation of results:

other: CLP/ EU GHS criteria not met, no classification required according to Regulation (EC) No 1272/2008

Conclusions:

CLP: not classified