Phenol, ethoxylated

Skin irritation / corrosion

Administrative data

Endpoint:

skin corrosion: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

02 October 2019 - 17 October 2019

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2019

Report date:

2019

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Deviations:

yes

Remarks:

See " Principles of method if other than guideline"

Principles of method if other than guideline:

The CV value of the PC after 3 min was above 30% therefore, acceptance criterion 3 was not met. However, as this was borderline above 30% (31.196%), the PC values at 1 hour met their acceptance criteria and the overall result for the test item was not close to the borderline, this deviation was considered to have had no impact on the overall outcome of the study.

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

2-phenoxyethanol

EC Number:

204-589-7

EC Name:

2-phenoxyethanol

Cas Number:

122-99-6

Molecular formula:

C8H10O2

IUPAC Name:

2-phenoxyethanol

Constituent 2

Reference substance name:

2-(2-phenoxyethoxy)ethanol

EC Number:

203-227-5

EC Name:

2-(2-phenoxyethoxy)ethanol

Cas Number:

104-68-7

Molecular formula:

C10H14O3

IUPAC Name:

2-(2-phenoxyethoxy)ethanol

Constituent 3

Reference substance name:

Triethylene glycol monophenyl ether

Cas Number:

7204-16-2

Molecular formula:

C12H18O4

IUPAC Name:

Triethylene glycol monophenyl ether

impurity 1

Reference substance name:

Unknown impurity of Phenol, ethoxylated

IUPAC Name:

Unknown impurity of Phenol, ethoxylated

Constituent 4

Reference substance name:

Water

EC Number:

231-791-2

EC Name:

Water

Cas Number:

7732-18-5

Molecular formula:

H2O

IUPAC Name:

Water

Test material form:

liquid

In vitro test system

Test system:

human skin model

Cell type:

non-transformed keratinocytes

Cell source:

other: Human-derived epidermal keratinocytes

Justification for test system used:

The EpiDermTM skin model and assay for skin corrosion testing is endorsed by OECD TG 431.

Vehicle:

unchanged (no vehicle)

Details on test system:

RECONSTRUCTED HUMAN EPIDERMIS (RHE) TISSUE
- Model used: MatTek Corporation EpidermTM reconstructed tissue model: EPI-200
- Tissue batch number(s): Lot: 30831
- Delivery date: 15 October 2019
- Date of initiation of testing: 02 October 2019

TEMPERATURE USED FOR TEST SYSTEM
- Temperature used during treatment / exposure: 37°C, 5% CO2, Relative Humidity: ≥95%


MTT DYE USED TO MEASURE TISSUE VIABILITY AFTER TREATMENT / EXPOSURE
- Incubation time: 60 minutes
- Spectrophotometer: BMG LabTech FluoStar Optima
- Wavelength: 570 nm
- Filter: no reference filter


FUNCTIONAL MODEL CONDITIONS WITH REFERENCE TO HISTORICAL DATA
- Viability: Pass
- Barrier function: Pass
- Morphology: Pass
- Contamination: Pass


NUMBER OF REPLICATE TISSUES: 3

CONTROL TISSUES USED IN CASE OF MTT DIRECT INTERFERENCE : Prior to the assay, the test item was checked for interference (water colouration or MTT interference) and found not to interfere.


NUMBER OF INDEPENDENT TEST SEQUENCES / EXPERIMENTS TO DERIVE FINAL PREDICTION: 3 tissues per condition

PREDICTION MODEL / DECISION CRITERIA (choose relevant statement)
- The test substance is considered to be corrosive to skin if the relative tissue viability after 3 minutes treatment exposure is less than 50%, or if the viability after 3 minutes exposure is greater than or equal to 50 % and the viability after 1 hour exposure is less than 15%.
- The test substance is considered to be non- corrosive to skin if the relative tissue viability after 3 minutes treatment exposure is more and after 1 hour is less than or equal to 15%.
- Justification for the selection of the cut-off point(s) if different than recommended in TG 431 and 439: Justification in accordance with Table 5 of testing guideline OECD 431

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): Single topical administration of 50µl of neat test item
- Concentration (if solution): Undiluted

VEHICLE : Not used

NEGATIVE CONTROL : Sterile water (tissue grade) (Lot: RNBH4825)
- Amount(s) applied (volume or weight): 50µl
- Concentration (if solution): Neat

POSITIVE CONTROL : Potassium Hydroxide (Lot: H3410)
- Amount(s) applied (volume or weight): 50µl
- Concentration (if solution): 8N

Duration of treatment / exposure:

3 and 60 minutes

Number of replicates:

3

Results and discussion

In vitro

Results

Results 1

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

3 minutes

Value:

89.006

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Results 2

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

60 minutes

Value:

29.186

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Other effects / acceptance of results:

- OTHER EFFECTS:
- Visible damage on test system: None reported
- Direct-MTT reduction: No direct reduction
- Colour interference with MTT: No colour interference


ACCEPTANCE OF RESULTS:
- Acceptance criteria met for negative control: The mean OD570 of the negative control tissues must be ≥0.8. Results for 3 minutes = 2.106 and 1 hour = 2.051 therefore passed
- Acceptance criteria met for positive control: The mean of the positive control relative percentage viability, after 1hour exposure must be < 15% of the mean of the negative control. The result was a pass at 7.875
- Acceptance criteria met for variability between replicate measurements: should not exceed 0.3 (30%), result = pass.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The skin corrosion potential of Phenol, ethoxylated was tested. The tissue viability of the test item treated tissues were assessed and compared to a negative control. The percentage viability obtained after 3 minutes was 89.006% and after 60 minutes was 29.186%. The substance did not meet the criteria for classification as a corrosive in accordance with CLP Regulation (EC) No. 1272/2008.

Executive summary:

The skin corrosion potential of Phenol, ethoxylated was evaluated using OECD Guideline 431 (In Vitro Skin Corrosion: Reconstructed Human Epidermis (RHE) Test Method). The test was GLP-compliant. Triplicate EpiDerm^TM skin model tissues were treated with a single topical application of 50µl of Phenol ethoxylated. Additional triplicate tissues were treated with 50µl of Sterile Water (Negative control) and 50µl of Potassium Hydroxide (Positive control). All tissues were exposed for 30 minutes and 60 minutes at 37°C, 5% CO2, ≥95% Relative Humidity, prior to the MTT endpoint. Corrosion is directly related to cytotoxicity in the EpiDerm™ tissue. Cytotoxicity is demonstrated by the reduction of MTT (3-[4,5dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide) to formazan by viable cells in the test item treated tissues compared to the corresponding negative control. The results are then used to make a prediction of the corrosivity potential of the test item. All controls were valid and demonstrated the reliability of the test system. Mean tissue viability (as a percentage of the negative control), was 89.006% and 29.186 % after 3 and 60 minutes of exposure, respectively. Therefore, Phenol ethoxylated does not meet the criteria for classification according to CLP Regulation (EC) No. 1272/2008.