Benzyltriphenylphosphonium, salt with 4,4'-[2,2,2-trifluoro-1-(trifluoromethyl)ethylidene]bis[phenol] (1:1)

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

SIT- Skin Irritation Test

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Benzyltriphenylphosphonium, salt with 4,4'- [2,2,2- trifluoro-1- (trifluoromethyl)ethylidene]bis[phenol] (1:1)

Cas Number:

75768-65-9

IUPAC Name:

Benzyltriphenylphosphonium, salt with 4,4'- [2,2,2- trifluoro-1- (trifluoromethyl)ethylidene]bis[phenol] (1:1)

Test material form:

solid

Details on test material:

Purity: 98 %

Specific details on test material used for the study:

Purity: > 98%

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

non-transformed keratinocytes

Cell source:

other: not reported

Source strain:

other: human cells

Vehicle:

unchanged (no vehicle)

Details on test system:

RECONSTRUCTED HUMAN EPIDERMIS (RHE) TISSUE
- Model used: EpiDerm(TM) Skin Kit (MatTek Corporation)
- Tissue batch number(s): not reported
- Production date: not reported
- Shipping date: not reported
- Delivery date: not reported
- Date of initiation of testing: 13 February 2017

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

REMOVAL OF TEST MATERIAL AND CONTROLS
-Volume and number of washing steps: The tissue inserts were filled and emptied 15 times using sterile CMF-DPBS. After the 15th rinse, the cell culture inserts were completely submerged, gently swirled, and rinse media dumped into a beaker containing 150 mL of CMF-DPBS three times. The tissues were rinsed once more on the inside and outside of the cell culture insert with sterile CMF-DPBS from a wash bottle, and the excess CMF-DPBS was decanted.
- Observable damage in the tissue due to washing: none reported
- Modifications to validated SOP: none

MTT DYE USED TO MEASURE TISSUE VIABILITY AFTER TREATMENT / EXPOSURE
- MTT concentration: 1.0 mg/mL
- Incubation time: 3±0.1 hours
- Spectrophotometer: Molecular Devices Vmax plate reader with the AUTOMIX function selected
- Wavelength: 570 nm

NUMBER OF REPLICATE TISSUES: 3

PREDICTION MODEL / DECISION CRITERIA (choose relevant statement)
- The test substance is considered to be an irritant to skin if the mean relative viability of the three treated tissues is less than or equal to 50% of the mean viability of the negative control.

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

25 mg of test substance

Duration of treatment / exposure:

60 ± 1 minutes

Duration of post-treatment incubation (if applicable):

42 ± 2 hours

Number of replicates:

3

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

% tissue viability

Value:

2.93

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

positive indication of irritation

Other effects / acceptance of results:

- OTHER EFFECTS:
- Visible damage on test system: none reported
- Direct-MTT reduction: There was no direct reduction of MTT
- Colour interference with MTT: There was no colour interference

ACCEPTANCE OF RESULTS:
- Acceptance criteria met for negative control: yes (mean OD570 was 1.575)
- Acceptance criteria met for positive control: yes (mean viability was 3.55%)
- Acceptance criteria met for variability between replicate measurements: yes (standard deviation calculated from individual percent tissue viabilities of the 3 identically treated replicates was <18% for the positive control and negative control)

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The test substance was predicted to be a skin irritant (mean viability was 2.93%).This result is probably reflecting the results of the existing in vivo supporting data, which indicated the substance caused transient slight erythema (1 of 6 rabbits) resolved by 48 hrs. The overall conclusion is the test substance causes slight irritation which reverses after 48h, which is conclusive but insufficient to classify as skin irritant.

Executive summary:

The purpose of this study was to evaluate the skin irritation potential of the test substance. The skin irritation potential was evaluated based upon measuring the relative conversion of MTT (3-[4,5 - dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) in the test article-treated tissues after exposure to the test article for a 60-minute exposure period, followed by a 42-hour post-exposure expression period. Skin irritation potential of the test article was predicted if the relative viability was less than or equal to 50%. The protocol was based upon the OECD guideline, “In VitroSkin Irritation: Reconstructed Human Epidermis Test Method” (TG439).

 

The substance was tested in one valid definitive assay to determine the identification and classification of skin irritation hazard according to the UN GHS classification system (Category 1/2 or No Category). The test substance was not observed to directly reduce MTT in the absence of viable cells. The test substance was not determined to be a colorant (was not considered to have potential interference with the MTT measurement. The test substance was predicted to be a skin irritant with a mean viability of 2.93%.