2-(1,2-dichloro-1,2,2-trifluoroethoxy)-1,1,2,2-tetrafluoroethanesulfonyl fluoride

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 25-August-2016 to 18-January-2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

GLP compliant

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:

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

Version / remarks:

Adopted 28 July 2015

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

Amended by Commission Regulation (EU) No 640/2012 of 06 July 2012

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Inspection dates: 02-04 June 2015 / Date of the certificate: 22 September 2015

Test material

Test material information

Constituent 1

Reference substance name:

2-(1,2-dichloro-1,2,2-trifluoroethoxy)-1,1,2,2-tetrafluoroethane-1-sulfonyl fluoride

EC Number:

604-439-4

Cas Number:

144728-59-6

Molecular formula:

C4Cl2F8O3S

IUPAC Name:

2-(1,2-dichloro-1,2,2-trifluoroethoxy)-1,1,2,2-tetrafluoroethane-1-sulfonyl fluoride

Test material form:

liquid

Details on test material:

See confidential details on test material

Specific details on test material used for the study:

TEST MATERIAL:
- Purity: 99.1%
- Appearance: Colourless liquid

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL:
- Controlled room temperature (15-25°C, below 70 RH%)

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

non-transformed keratinocytes

Justification for test system used:

The EPISKIN (SM) model has been validated for irritation testing in an international validation study and its use is recommended by the relevant OECD guideline for irritation testing (OECD No. 439); therefore, it was considered to be suitable for this study.

Vehicle:

unchanged (no vehicle)

Details on test system:

RECONSTRUCTED HUMAN EPIDERMIS (RHE) TISSUE
- Model used: EPISKIN Small ModelTM (EPISKIN-SMTM, 0.38 cm2)
- Tissue batch number(s): 16-EKIN-035
- Source: SkinEthic Laboratories, Lyon, France

TEMPERATURE USED FOR TEST SYSTEM
- Temperature used during treatment / exposure: All incubations, with the exception of the test item incubation of 15 minutes at room temperature, were carried out at 37.0 °C
- Temperature of post-treatment incubation: 37.0 °C

MTT DYE USED TO MEASURE TISSUE VIABILITY AFTER TREATMENT / EXPOSURE
- MTT concentration: 0.3 mg/mL
- Incubation time: 3 hours (± 5 min) at 37°C in an incubator with 5% CO2, in a >95% humidified atmosphere, protected from light
- Spectrophotometer: Not specified
- Wavelength: 570 nm

FUNCTIONAL MODEL CONDITIONS WITH REFERENCE TO HISTORICAL DATA
- Viability: IC50 = 1.8 mg/mL [1.5 mg/mL =< IC50 =< 3 mg/mL]
- Barrier function: Histology scoring: 22.5 +/- 0.4 (CV= 2.0%) [>= 19.5]
- Morphology: Well-differentiated epidermis consisting of a basal layer, several spinous and granular layers and a thick stratum corneum = satisfactory
- Contamination: EPISKINTM (SM) kits are manufactured according to defined quality assurance procedures (certified ISO 9001). All biological components of the epidermis and the kit culture medium have been tested for the presence of viruses, bacteria and mycoplasma.
- Reproducibility:
- Histology: probability 0.95 that 100% of the batch > 20
- IC50: probability 0.95 that IC50 >= 1.8 mg/mL (threshold value)

NUMBER OF REPLICATE TISSUES: 3 tissues per test item together with negative and positive controls

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

PREDICTION MODEL / DECISION CRITERIA
- The test substance is considered to be irritant to skin if the relative mean tissue viability of three individual tissues after 15 minutes of exposure and 42 hours post incubation is less than or equal to 50% of the mean viability of the negative controls.
- The test substance is considered to be non-irritant to skin if the relative mean tissue viability of three individual tissues after 15 minutes of exposure and 42 hours post incubation is greater than 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 (volume or weight with unit): 10 µL
- Concentration: Undiluted test item.

VEHICLE CONTROL
Not relevant.

NEGATIVE CONTROL
- Amount(s) applied (volume or weight): 50 µL

POSITIVE CONTROL
- Amount(s) applied (volume or weight): 50 µL
- Concentration (if solution): 5% (w/v)

Duration of treatment / exposure:

15 minutes (± 0.5 min) at room temperature (26.3-27.5°C)

Duration of post-treatment incubation (if applicable):

42 hours (± 1h) at 37°C in an incubator with 5% CO2, in a >95% humidified atmosphere

Number of replicates:

3

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

% tissue viability

Remarks:

Mean of the 3 replicates

Value:

94.8

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Remarks:

100.0%

Positive controls validity:

valid

Remarks:

4.0%

Remarks on result:

no indication of irritation

Other effects / acceptance of results:

ACCEPTANCE OF RESULTS:
- The mean OD value of the three negative control tissues should be between 0.6 and 1.5, and the standard deviation value (SD) of the % viability values should be ≤ 18.
- The acceptable mean percentage viability range for positive controls is 0-40% and the standard deviation value (SD) of the % viability values should be ≤ 18.
- The SD calculated from individual % tissue viability values of the three test item treated replicates should be <18.
- The mean OD value of the blank samples (acidified isopropanol) should be <0.1.

Any other information on results incl. tables

Optical Density(OD) and the calculated relative viability % of the samples

Substance	Optical Density (OD)			Viability (% RV)
		Measured	Blank corrected
Negative control:    Phosphate Buffered Saline	1 2 3	0.842 0.779 0.787	0.795 0.732 0.740	105.2 96.9 97.9
	mean	--	0.756	100.0
Positive control:    5% (w/v) SDS solution	1 2 3	0.075 0.084 0.070	0.029 0.038 0.023	3.8 5.0 3.1
	mean	--	0.030	4.0
Test item:    Fluorosulfonic Adduct	1 2 3	0.761 0.766 0.763	0.714 0.719 0.716	94.5 95.1 94.8
	mean	--	0.717	94.8

1. Mean blank value was 0.046.

2. Optical density means the mean value of the duplicate wells for each sample (rounded to three decimal places).

Validity of the test

After receipt, the two indicators of the delivered kit were checked. Based on the observed colours, the epidermis units were in proper conditions.

The mean OD value of the three negative control tissues was in the recommended range (0.756). Standard deviation of the viability results for negative control samples was 4.5.

The positive control treated tissues showed 4.0% viability demonstrating the proper performance of the assay. The standard deviation of the viability results for positive control samples was 1.0.

The standard deviation of viability values of the three test item-treated tissue samples in the MTT assay was 0.3.

The mean OD value of the blank samples (acidified isopropanol) was 0.046.

All these parameters met the acceptability criteria, therefore the study was considered to be valid.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Fluorosulfonic adduct is not irritant in the in vitro skin irritation test (OECD Guideline No. 439, adopted 28 July 2015 and, EU Method B.46, amended 06 July 2012) under the experimental conditions described in this report.
The substance is not classified as irritant to skin according to GHS criteria.

Executive summary:

The assessment of the irritant potential to skin of Fluorosulfonic adduct was carried out, under GLP compliance, using an in vitro skin irritation test based on the guidelines described in: OECD No. 439 (adopted 28 July 2015) and EU Method B.46 (Amended by Commission Regulation (EU) No 640/2012 of 06 July 2012).

Disks of reconstructed human epidermis model. EPISKIN^TM (SM) (three units) were treated with the test item (10 µL) and incubated for 15 minutes at room temperature. Exposure of the undiluted test item was terminated by rinsing with Phosphate Buffered Saline (PBS). The epidermis units were then incubated at 37°C for 42 hours in an incubator with 5% CO2. The viability of each disk was assessed by incubating the tissues for 3 hours with MTT solution at 37°C in an incubator with 5% CO2 protected from light. The precipitated formazan crystals were then extracted using acidified isopropanol and quantified spectrophotometrically.

Following exposure with Fluorosulfoni Adduct, the mean cell viability was 94.8% compared to the negative control. This is above the threshold of 50%, therefore the test item was considered as being non-irritant to skin. The experiment met the validity criteria, therefore the study was considered to be valid. In conclusion, Fluorosulfonic Adduct is considered to be non-irritant. The substance is not classified as irritant to skin according to GHS criteria.