Lithium difluoro(oxalato)borate(1-)

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2021.01

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2021

Report date:

2021

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Lithium difluoro(oxalato)borate(1-)

EC Number:

803-919-2

Cas Number:

409071-16-5

Molecular formula:

C2BF2LiO4

IUPAC Name:

Lithium difluoro(oxalato)borate(1-)

Test material form:

solid: particulate/powder

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source (i.e. manufacturer or supplier) and lot/batch number of test material:
Provided by sponsor, Batch No.:G200810043

- Purity, including information on contaminants, isomers, etc.:
99.80%


STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material:
Refrigeration (+2 to +8°C)

In vitro test system

Test system:

human skin model

Remarks:

EpiSkin

Source species:

other: a three dimensional Reconstructed Human Epidermis model

Cell type:

non-transformed keratinocytes

Cell source:

other: cultured on a collagen matrix at the air liquid interface

Details on animal used as source of test system:

SkinEthic Laboratories
4, rue Alexander Fleming - 69366
Lyon, Cedex 07
France

The EpiSkin kit is produced by SkinEthic and sourced through a local supplier.

Justification for test system used:

The assessment of skin irritation has typically involved the use of laboratory animals (OECD TG 404). In relation to animal welfare concerns, TG 404 recommends the use of a tiered testing strategy for the determination of skin corrosion and irritation which includes the use of validated in vitro or ex vivo test methods avoiding pain and suffering of animals.

One of the validated in vitro test methods adopted by the OECD TG 439 makes use of reconstructed human epidermis (RhE) which closely mimics the biochemical and physiological properties of the upper parts of the human skin, i.e. the epidermis.

Vehicle:

unchanged (no vehicle)

Details on test system:

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

REMOVAL OF TEST MATERIAL AND CONTROLS
After the respective incubation periods, at room temperature, the epidermis units were removed from the wells and thoroughly rinsed with PBS placed on an absorbent paper to remove excess PBS. The epidermis units were then placed in a 12-well plate filled with 2 mL pre-warmed assay medium to rinse.

After rinsing, each of these epidermal units was gently tapped on an absorbent paper to remove excess assay medium.


DYE BINDING METHOD
- Dye used in the dye-binding assay: [ MTT ]
- Spectrophotometer:
Microplate reader Flex Station
- Wavelength:
570 nm

NUMBER OF INDEPENDENT TESTING RUNS / EXPERIMENTS TO DERIVE FINAL PREDICTION:
1
PREDICTION MODEL / DECISION CRITERIA (choose relevant statement)

Mean tissue viability % is ≤ 50 % Category 2 or Category 1
Mean tissue viability % is > 50 % Non-Irritant

Control samples:

yes, concurrent negative control

yes, concurrent no treatment

Amount/concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 10 mg
- Concentration (if solution):

NEGATIVE CONTROL
- Amount(s) applied (volume or weight): 10 μL PBS
- Concentration (if solution):

POSITIVE CONTROL
- Amount(s) applied (volume or weight): 10 μL Sodium Dodecyl Sulfate
- Concentration (if solution): 5%

Duration of treatment / exposure:

15 min

Duration of post-treatment incubation (if applicable):

4 hour

Number of replicates:

3

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

3

Value:

17.83

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Applicant's summary and conclusion

Interpretation of results:

Category 2 (irritant) based on GHS criteria

Conclusions:

The mean relative tissue viability for the test item, Lithium difluoro(Oxalato)borate(1-) was 17.83 % and hence, it is predicted to be irritant under the experimental conditions described in this report.

Executive summary:

The test item, Lithium difluoro(Oxalato)borate(1-) was tested for its possible skin irritation potential using a three-dimensional Reconstructed Human Epidermis model, EpiSkin, through topical application for 15 minutes.

 

The test item is a powder and after moistening with 5 µL of water on the top of the skin tissues at 10 mg/tissue and exposed for 15 minutes.  

 

Ten microliters (10 µL) of PBS and 10 µL of 5% aqueous SDS were used as the negative and positive controls, respectively.

 

After 4-hour post-incubation period, irritation potential of Lithium difluoro(Oxalato)borate(1-) was evaluated by assessing the reduction of cell viability after exposure to the test item. Cell viability was measured by determining mitochondrial dehydrogenase activity measured by formazan production from MTT at the end of the treatment.The relative mean tissue viability obtained after 15 minutes treatment with the test item was compared to the negative control tissues.

 

The absolute mean OD₅₇₀ (optical density at 570 nm) of the negative control tissues was 0.827. The positive control had a mean cell viability of 4.88 % after 15 minutes exposure, indicating that the test system functioned properly.

 

The study indicated that the test item as the percent viability was 17.83 %, in this In Vitro Skin Irritation Test using Reconstructed Human Epidermis under the conditions of testing employed.