Phosphoric acid, mixed esters with alcohols, C7-9-iso-, C8-rich and alcohols, C11-14-iso-, C13-rich, ethoxylated, potassium salt

Skin irritation / corrosion

Administrative data

Endpoint:

skin corrosion: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

July-October 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:

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

Version / remarks:

from 29 July 2016

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.40 (In Vitro Skin Corrosion: Transcutaneous Electrical Resistance Test (TER))

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

other: MatTek Corporation Protocol for: In Vitro EpiDermTM Skin Corrosion Test (EPI-200-SCT) For use with MatTek Corporation’s Reconstructed Human Epidermal Model EpiDerm; Version 07/11/2014

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Phosphoric acid, mixed esters with alcohols, C7-9-iso-, C8-rich and alcohols, C11-14-iso-, C13-rich, ethoxylated, potassium salt

EC Number:

947-738-8

Molecular formula:

Molecular formulas of exemplary components: C33H68KO10P C49H100KO16P C24H49K2O10P C24H50KO10P C16H34KO4P C8H17K2O4P C8H18KO4P

IUPAC Name:

Phosphoric acid, mixed esters with alcohols, C7-9-iso-, C8-rich and alcohols, C11-14-iso-, C13-rich, ethoxylated, potassium salt

Test material form:

liquid

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

non-transformed keratinocytes

Cell source:

other: single donor neonatal-foreskin tissue or, alternatively, adult breast skin

Vehicle:

unchanged (no vehicle)

Details on test system:

RECONSTRUCTED HUMAN EPIDERMIS (RHE) TISSUE
- Model used: EpiDermTM (MatTek)
- Tissue batch number(s): 25835
- Production date:
- Shipping date:
- Delivery date:
- Date of initiation of testing: 7 August 2017

TEMPERATURE USED FOR TEST SYSTEM
- Temperature used during treatment / exposure: 37 +/- 1°C
- Temperature of post-treatment incubation (if applicable): 37 +/- 1°C

REMOVAL OF TEST MATERIAL AND CONTROLS
-Volume and number of washing steps: 20 times with PBS after 3 and 60 minute incubation with test item; twice with PBS after incubation with MTT

MTT DYE USED TO MEASURE TISSUE VIABILITY AFTER TREATMENT / EXPOSURE
- MTT concentration: final concentration 1 mg/mL
- Incubation time: 3 hrs
- Spectrophotometer: plate spectrophotometer
- Wavelength: 570 nm
- Filter:
- Filter bandwidth:
- Linear OD range of spectrophotometer:

NUMBER OF REPLICATE TISSUES: 2

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

PREDICTION MODEL / DECISION CRITERIA
- The test substance is considered to be corrosive to skin if [complete, e.g. the viability after 3 minutes 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 [complete, e.g. the viability after 3 minutes exposure is greater than or equal to 50% and the viability after 1 hour exposure is greater than or equal to 15%.]

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 50 uL

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

POSITIVE CONTROL
- Amount(s) applied (volume or weight): 50 uL

Duration of treatment / exposure:

3-minute experiment
60-minute experiment

Duration of post-treatment incubation (if applicable):

3 hrs

Number of replicates:

2

Results and discussion

In vitro

Results

Results 1

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

mean of 2 values

Value:

17.6

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

other: after 3 minutes

Results 2

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

mean of 2 values

Value:

25.8

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

other: after 60 minutes

Other effects / acceptance of results:

- OTHER EFFECTS:
The mixture of 50 µL test item per 1 mL MTT medium showed no reduction of MTT as compared to the solvent. The mixture did not turn blue/purple. Therefore, NSMTT equalled 0%.
The mixture of 50 µL test item per 300 µL Aqua dest. and per 300 µL isopropanol showed no colouring as compared to the solvent. Therefore NSCliving equalled 0%.

DEMONSTRATION OF TECHNICAL PROFICIENCY: YES

ACCEPTANCE OF RESULTS:
- Acceptance criteria met for negative control: YES
- Acceptance criteria met for positive control: YES
- Acceptance criteria met for variability between replicate measurements: YES for 3-minute experiment; NO for 60-minute experiment (coefficient of variation clearly exceeding the 30% threshold (66.2%))

Applicant's summary and conclusion

Interpretation of results:

Category 1A (corrosive) based on GHS criteria

Conclusions:

The test item showed clearly corrosive effects. The mean relative tissue viability (% negative control) was reduced below 25% (17.6%) after 3 min treatment. Therefore, the test item will be classified as “corrosive”, optional sub-category 1A.
After 60 min treatment, mean tissue viability was reduced to 25.8%. The two tissues treated identically showed a high coefficient of variation, clearly exceeding the 30% threshold (66.2%). This is accepted since the 60 min treatment period has no impact on classification or sub-categorization of the test item.