4-(Difluoro-(3,4,5-trifluoro-phenoxy)-methyl)-3,5-difluoro-benzaldehyde

Skin irritation / corrosion

Administrative data

Endpoint:

skin corrosion: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

September 26, 2017 -November 13, 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

Test guideline 1

Qualifier:

according to guideline

Guideline:

other: Council Regulation (EC) No. 440/2008 laying down test methods pursuant to Regulation (EC) No. 1907/2006. B.40.bis. In vitro skin corrosion: human skin model test

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

July 29, 2016

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

other: INVITTOX Protocol SkinEthic Skin Corrosivity Test, April 2012.

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

4-(Difluoro-(3,4,5-trifluoro-phenoxy)-methyl)-3,5-difluoro-benzaldehyde

Cas Number:

685563-70-6

Molecular formula:

C14H5F7O2

IUPAC Name:

4-(Difluoro-(3,4,5-trifluoro-phenoxy)-methyl)-3,5-difluoro-benzaldehyde

Test material form:

solid: crystalline

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

non-transformed keratinocytes

Cell source:

foreskin from a single donor

Justification for test system used:

standard model

Vehicle:

unchanged (no vehicle)

Remarks:

No vehicle used in this study; The test item was applied neat to the tissues.

Details on test system:

CELL CULTURE
- Supplier: EpiSkin/SkinEthic Laboratories, Lyon, France)
- Source: human keratinocytes cultured on a polycarbonate filter in conditions which permit their terminal differentiation
- Format: 24 well plate
- Batch: 17-RHE-108
- Expires: October 30, 2017

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

REMOVAL OF THE TEST MATERIAL AND CONTROL
At the end of the exposure periods, the test item, positive and negative control was removed immediately by gently rinsing with a minimum volume of 20 mL DPBS using a pipette. Excess DPBS was removed by gently shaking the tissue inserts and blotting the bottom of the tissue inserts with blotting paper.

Control samples:

yes, concurrent negative control

Amount/concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 20 mg ± 3 mg of solid test material
- Concentration (if solution): n/a

VEHICLE
- Amount(s) applied (volume or weight with unit): n/a
- Concentration (if solution): n/a
- Lot/batch no. (if required): n/a
- Purity: n/a

NEGATIVE CONTROL
- Amount(s) applied (volume or weight): 40 µL ± 3 µl (deionised water )
- Concentration (if solution): n/a

POSITIVE CONTROL
- Amount(s) applied (volume or weight): 40 µL ± 3 µl
- Concentration (if solution): An 8 N potassium hydroxide solution dissolved deionised water pure was used as positive control.

Duration of treatment / exposure:

3 min & 1 hour

Number of replicates:

2

Results and discussion

In vitro

Results

Results 1

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

Experiment 1 / Run 1 (3 min)

Value:

98.6

Vehicle controls validity:

not applicable

Remarks:

The test item was applied neat to the tissues

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

other: Non-corrosive

Results 2

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

Experiment 1 / Run 1 (1 hour)

Value:

99.6

Vehicle controls validity:

not applicable

Remarks:

The test item was applied neat to the tissues

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

other: Non-corrosive

Other effects / acceptance of results:

OTHER EFFECTS:
- Visible damage on test system: none
- Direct-MTT reduction: none
- Colour interference with MTT: none

ACCEPTANCE OF RESULTS:

Acceptability of the Quality Control Data of the Skin Model with Reference to Historical Batch Data:
The negative control OD values were 1.719, 1.745, 1.743 and 1.661 and, thus, in the range of ≥ 0.8 and ≤ 3.0.

Acceptability of the Positive and Negative Control Data:
After treatment with the positive control (potassium hydroxide, 8N) the mean viability value was 0.5 % and, thus, lower than the historically established threshold of 0.97 %.
After treatment with the negative control (deionised water) the mean ODs were 1.731 (3 minute exposure) and 1.703 (1 hour exposure) and, thus, higher than the historically established thresholds of 1.590 and 1.468, respectively.

Negative Control, Positive Control and Test Substance Data Acceptance Criteria:
The range between identically treated tissues with the negative control was less than 30 % after 3 minutes exposure (1.4 %) and after 1 hour exposure (5.1 %).
The range between identically treated tissues with the positive control was higher than 30 % after 1 hour exposure (50.0 %), but the optical densities measured were <0.3.
The range between identically treated tissues with the test item was less than 30 % after 3 minutes exposure (0.3 %) and after 1 hour exposure (7.2 %).


The study met all acceptance criteria.

Any other information on results incl. tables

Group	Time / [min]	Mean OD	Mean Relative viability / [%]
Negative Control	3	1.731	100.0
Negative Control	60	1.703	100.0
Positive Control	60	0.009	0.5
Test Material	3	1.706	98.6
Test Material	60	1.696	99.6

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

This study was performed according to GLP and the methods applied are fully compliant with OECD TG 431. Under the conditions of the present study, the test item is not considered to possess a corrosive potential to skin.

Executive summary:

This study was performed according to GLP and the methods applied are fully compliant with OECD TG 431. Under the conditions of the present study, the test item is not considered to possess a corrosive potential to skin.