Ethyl decanoate

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 24 November 2017 to 14 December 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Deviations:

yes

Remarks:

No analysis certificate of the episkin model was given.

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Ethyl decanoate

EC Number:

203-761-9

EC Name:

Ethyl decanoate

Cas Number:

110-38-3

Molecular formula:

C12H24O2

IUPAC Name:

ethyl decanoate

Test material form:

liquid

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: From the sponsor, batch : 16090585
- Expiration date of the lot/batch: 19 september 2018
- Purity test date: 22 September 2016

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: room temperature
- Stability under test conditions:at least 6 months from the manufacture date
- Solubility and stability of the test substance in the solvent/vehicle: not applicable
- Reactivity of the test substance with the solvent/vehicle of the cell culture medium: not applicable

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: not applicable, the test item was used pure
- Final dilution of a dissolved solid, stock liquid or gel: not applicable
- Final preparation of a solid: not applicable

FORM AS APPLIED IN THE TEST (if different from that of starting material)

In vitro test system

Test system:

artificial membrane barrier model

Remarks:

Reconstructed human epidermis

Source species:

human

Cell type:

non-transformed keratinocytes

Cell source:

other: not applicable

Source strain:

other: not applicable

Justification for test system used:

The present test is proposed as an alternative in vitro approach to assess the skin irritant potential of chemicals or cosmetic ingredient.

Vehicle:

unchanged (no vehicle)

Details on test system:

RECONSTRUCTED HUMAN EPIDERMIS (RHE) TISSUE
- Model used: EpiSkinTM
- Tissue batch number(s): lot 17-EKIN-047
- Production date: not specified
- Shipping date: not specified
- Delivery date: not specified
- Date of initiation of testing: 21 November 2017

TEMPERATURE USED FOR TEST SYSTEM
- Temperature used during treatment / exposure: 37°C
- Temperature of post-treatment incubation (if applicable): 37°C ± 1°C

REMOVAL OF TEST MATERIAL AND CONTROLS
-Volume and number of washing steps: thoroughly rinsed with PBS
- Observable damage in the tissue due to washing: not specified
- Modifications to validated SOP:no modification

MTT DYE USED TO MEASURE TISSUE VIABILITY AFTER TREATMENT / EXPOSURE
- MTT concentration: 1mg/ml
- Incubation time: 3 hours
- Spectrophotometer: not specified
- Wavelength: 570nm
- Filter: not filter used
- Filter bandwidth: not applicable
- Linear OD range of spectrophotometer: not specified

FUNCTIONAL MODEL CONDITIONS WITH REFERENCE TO HISTORICAL DATA
- Viability: yes
- Barrier function: yes
- Morphology: stratified differentiated epidermis derived from human keratinocytes
- Contamination: not specified
- Reproducibility:yes

NUMBER OF REPLICATE TISSUES: triplicates were used

CONTROL TISSUES USED IN CASE OF MTT DIRECT INTERFERENCE
- Killed tissues
- Procedure used to prepare the killed tissues (if applicable): Freezed-killed tissue
- N. of replicates : triplicates
- Method of calculation used: % viability = [OD mean of treated condition / OD mean of control condition] x 100

NUMBER OF INDEPENDENT TEST SEQUENCES / EXPERIMENTS TO DERIVE FINAL PREDICTION: 2 independant tests :pretest with interference and MTT reduction test and main test

PREDICTION MODEL / DECISION CRITERIA (choose relevant statement)
- The test substance is considered to be irritant to skin if the viability after 30 minutes exposure and 42 hours post incubation is less than 50%.
- The test substance is considered to be non-irritant to skin if the viability after 30 minutes exposure and 42 hours post incubation is greater than or equal to 50%.

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 50µL/cm2 corresponding to 19 µL (0.38cm2)
- Concentration (if solution): pure

VEHICLE
Not applicable

NEGATIVE CONTROL
- Amount(s) applied (volume or weight): 19 µL
- Concentration (if solution): pure

POSITIVE CONTROL
- Amount(s) applied (volume or weight): 19µL
- Concentration (if solution): 5%

Duration of treatment / exposure:

15 ± 0.5 minutes

Duration of post-treatment incubation (if applicable):

42 hours

Number of replicates:

triplicates were used

Results and discussion

In vitro

Results

Results 1

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

Main test - Negative control

Value:

100

Negative controls validity:

valid

Positive controls validity:

valid

Results 2

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

Main test - Test item

Value:

100

Negative controls validity:

valid

Positive controls validity:

valid

Results 3

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

Main test - Positive control

Value:

17

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: the 5% SDS was used as positive control and showed proficiency of the test system to detect cellular cytotoxicity

ACCEPTANCE OF RESULTS:
- Acceptance criteria met for negative control: conform
- Acceptance criteria met for positive control: conform
- Acceptance criteria met for variability between replicate measurements: conform
- Range of historical values if different from the ones specified in the test guideline: Historical values of positive control : 14±4% ; Positive control values in the test : 17%. Conform

Any other information on results incl. tables

Table 1 :Results

Condtion	Optical Density Mean	Cellular viability
Negative control	1.522 ± 0.012	100
Positive control	0.257 ± 0.015	17
Test item	1.523 ± 0.016	100

 

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Based on the result of this study, the test item when applied on the EpiSkin model for 15 minutes did not induce a decrease of cellular viability. Hence, according to the CLP criteria, the test item, caprate ethyl, was not classified for skin irritation.

Executive summary:

This GLP compliant study was performed in order to assess the potential skin irritation potential of the test item, caprate ethyl. This study was performed according to the OECD TG 439 method.

EpiSkinTM was used as test system in this study. 19 µL of caprate ethyl was applied on the EpiSkinTM for 15 minutes. Buffered saline solution (PBS) was used as negative control and 5% Sodium dodecyl sulfate (SDS) was used as positive control. Triplicates were used for each condition. The 15 minutes exposure period was followed by a 42 hours post incubation period. After this step, the viability of the EpiSkinTM model was measured by a MTT assay.

The postive control induceda decrease of cellular viability (17% of viability). The negative control did not induced a viability decrease. The viability of the test system was 100% when exposed to the test item.

The acceptance criteria of the assay was considered as validated.

Based on the result of this study, the test item whan applied on the EpiSkin model for 15 minutes did not induce a decrease of cellular viability. Hence, according to the CLP criteria, the test item, caprate ethyl, was not classified for skin irritation.