4-bromo-3,3,4,4-tetrafluorobut-1-ene

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

24-28 February 2020

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2020

Report date:

2020

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

18 June 2019

Deviations:

yes

Remarks:

See "Any other information on materials and methods incl. tables"

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

4-bromo-3,3,4,4-tetrafluorobut-1-ene

EC Number:

242-440-8

EC Name:

4-bromo-3,3,4,4-tetrafluorobut-1-ene

Cas Number:

18599-22-9

Molecular formula:

C4H3BrF4

IUPAC Name:

4-bromo-3,3,4,4-tetrafluorobut-1-ene

Test material form:

liquid

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

non-transformed keratinocytes

Cell source:

foreskin from a single donor

Source strain:

other:

Vehicle:

unchanged (no vehicle)

Details on test system:

The EpiDerm™ Model (EPI-200) (MatTek Corporation, Ashland, USA) consists of normal, human derived epidermal keratinocytes which have been cultured to form a multilayered, highly differentiated model of the human epidermis. It consists of organized basal, spinous and granular layers, and a multilayered stratum corneum containing intercellular lamellar lipid layers arranged in patterns analagous to those found in vivo. The EpiDerm™ Model incorporates several features which make it advantageous in the study of the potential dermal toxicity. First, the test system uses a serum-free medium which eliminates the possibility of serum protein and test article interaction [1]. Secondly, the target cells are epithelial, derived from human skin. Third, since the tissue has a functional stratum corneum, the test materials are applied directly to the tissue surface, at air interface, so that undiluted and/or end use dilutions can be tested directly.

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Duration of post-treatment incubation (if applicable):

42 ± 2 hours

Number of replicates:

3 tissues/treatment

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

1 experiment

Value:

10.04

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Remarks:

3.18%

Any other information on results incl. tables

The figure below summarizes the results of the Skin Irritation Test (SIT) for the test article and the positive control. The assay results were accepted. The mean OD570 of the negative control, sterile Ca++ and Mg+ Free Dulbecco’s Phosphate Buffered Saline (CMF-DPBS) was 1.712. The mean viability of the positive control, 5% SDS, was 3.18%. The standard deviation calculated from individual percent tissue viabilities of the 3 identically treated replicates was <18% for the positive and negative controls. The test article was not observed to directly reduce MTT in the absence of viable cells. The test article was not considered to have potential interference with the MTT measurement (was not considered a colorant).

Applicant's summary and conclusion

Interpretation of results:

other: requires further testing for classification and labeling for skin irritation according to UN GHS and EU classification system (Category I/II)

Conclusions:

The mean viability of the test substance was 10.0%. Based upon the results of this assay and according to the prediction model presented in OECD TG 439, the test substance was predicted to be an irritant. Additional testing would be needed to determine if the test article was a GHS Category 1 (Severe/ Corrosive) or GHS Category 2 (Irritant) for skin irritation.

Executive summary:

The EpiDerm™ Skin Model (MatTek Corporation, MA, USA) was used to assess the potential dermal irritation of the test substance. The MTT (3‑[4,5‑dimethylthiazol‑2‑yl]‑2,5‑diphenyltetrazolium bromide) conversion assay, which measures the NAD(P)H‑dependent microsomal enzyme reduction of MTT (and to a lesser extent, the succinate dehydrogenase reduction of MTT) to a blue formazan precipitate, was used to assess cellular metabolism after exposure to the test substance. The protocol was based upon the OECD guideline, “In Vitro Skin Irritation: Reconstructed Human Epidermis Test Method” (TG 439). Under the conditions specified in this study, the mean viability of the tissues treated with the test article was 10.0%. According to the prediction model presented in OECD TG 439, the test substance was predicted to be an irritant. Additional testing would be needed to determine if the test article was a GHS Category 1 (Severe/Corrosive) or GHS Category 2 (Irritant) for skin irritation.