Tetrazinc trioxide phosphite

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 November 2017 - 22 December 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

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:

July 29, 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

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Tetrazinc trioxide phosphite

EC Number:

264-938-4

EC Name:

Tetrazinc trioxide phosphite

Cas Number:

64539-51-1

Molecular formula:

HO6PZn4

IUPAC Name:

Tetrazinc trioxide phosphite

Specific details on test material used for the study:

Batch: 1013Q17761
Purity: 100%
Appearance: White powder
Expiry Date: 25 June 2017
Storage Conditions: At room temperature

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

non-transformed keratinocytes

Justification for test system used:

As per OECD Test Guideline.

Vehicle:

water

Control samples:

yes, concurrent vehicle

yes, concurrent positive control

Amount/concentration applied:

25 μL of deionised water and 25 ± 2mg (39.7 mg/cm2 according to guideline) of the test item.
Each 50 μL were applied to each set of duplicate tissues.

Duration of treatment / exposure:

• Test Item: 3 ± 0.5 minutes, 60 ± 5 minutes
• Negative Control: 3 ± 0.5 minutes, 60 ± 5 minutes
• Positive Control: 3 ± 0.5 minutes, 60 ± 5 minutes

Duration of post-treatment incubation (if applicable):

3 hour post-treatment incubation period

Number of replicates:

Duplicate.

Results and discussion

In vitro

Results

Results 1

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

3 minute

Value:

103.1

Vehicle controls validity:

valid

Negative controls validity:

not applicable

Positive controls validity:

valid

Remarks on result:

no indication of irritation

Results 2

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

60 minutes

Value:

89.2

Vehicle controls validity:

valid

Negative controls validity:

not applicable

Positive controls validity:

valid

Remarks on result:

no indication of irritation

Other effects / acceptance of results:

ACCEPTANCE OF RESULTS:
- Acceptance criteria met for negative control: the mean OD of the tissue replicates treated with the negative control is ≥ 0.8 and ≤ 2.8 for every exposure time (range: 1.535 to 1.700)
- Acceptance criteria met for positive control: the mean viability of the tissue replicates treated with the positive control for 1 hour, is <15% compared to the negative control (2.4%)
- Acceptance criteria met for variability between replicate measurements: the Coefficient of Variation (CV) in the range 20 – 100% viability between tissue replicates is ≤ 30% (range: 0.4% to 5.4%)

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The substance is considered to be a non-corrosive to skin.

Executive summary:

In an in vitro skin corrosion study human skin tissue (eipdermis keratinocytes) was exposed to the substance for 3-minutes and 1-hour. There was 103.1% and 89.2% tissue viability following the 3-minutes and 1-hour exposure points, respectively. Resultantly, the substance is considered to be a non-corrosive to skin.