Lithium difluoro(oxalato)borate(1-)

Eye irritation

Administrative data

Endpoint:

eye 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 437 (Bovine Corneal Opacity and Permeability Test Method for Identifying i) Chemicals Inducing Serious Eye Damage and ii) Chemicals Not Requiring Classification for Eye Irritation or Serious Eye Damage)

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)

Test animals / tissue source

Species:

cattle

Strain:

other: Cornea

Details on test animals or tissues and environmental conditions:

SOURCE OF COLLECTED EYES
- Source:
Local abattoir (Slaughter house), Near Frazer
town, Bengaluru.

- Number of animals:
3

- Characteristics of donor animals (e.g. age, sex, weight):
Between 3 to 4 years

- Storage, temperature and transport conditions of ocular tissue (e.g. transport time, transport media and temperature, and other conditions):
The bovine eyes were procured from local abattoir and transported in a jar containing Hank’s Balanced Salt Solution (HBSS) and penicillinstreptomycin (100 IU/mL & 100 μg/mL) in an ice box. The experiment was initiated within 6 hours from the collection of eyes.

- Time interval prior to initiating testing:

- Indication of any existing defects or lesions in ocular tissue samples:
none

- Indication of any antibiotics used:
penicillin-streptomycin (100 IU/mL & 100 μg/mL).

- Selection and preparation of corneas:
Post pretest examination, all eyes were dissected with approximately 2-mm to
3-mm sclera with cornea from surrounding tissue and then placed in a
container with fresh HBSS (Hank’s Balanced Salt Solution), containing
penicillin-streptomycin (100 IU/mL & 100 μg/mL).

- Quality check of the isolated corneas:
Immediately after receiving the eyes in the lab, all eyes were observed for any
evidence of vascularization, pigmentation, opacity or scratches. All fourteen
collected eyes were found to be suitable for the experiment purpose.

Test system

Vehicle:

water

Controls:

yes, concurrent positive control

yes, concurrent negative control

Amount / concentration applied:

positive control: 0.75 ml 20% w/v Imidazole
negative control: 0.75 ml undiluted distilled water
test group: 0.75 ml 20% w/v test material

Duration of treatment / exposure:

4 hour

Duration of post- treatment incubation (in vitro):

1 hour

Number of animals or in vitro replicates:

3

Details on study design:

NUMBER OF REPLICATES
3
NEGATIVE CONTROL USED
Negative control (Distilled water)

POSITIVE CONTROL USED
positive control (Imidazole)

APPLICATION DOSE AND EXPOSURE TIME
20% w/v
4 hour

TREATMENT METHOD:
closed chamber

POST-INCUBATION PERIOD:
yes. 1 hour

REMOVAL OF TEST SUBSTANCE
- Number of washing steps after exposure period:
the test substances from anterior chambers were removed and washed with EMEM (with phenol red) until test material was completely removed from the corneal surface. A final wash was made with EMEM without phenol red. Both the chambers were filled with fresh EMEM (without phenol red) and final opacity was measured.

- POST-EXPOSURE INCUBATION:

METHODS FOR MEASURED ENDPOINTS:
- Corneal opacity:
- Corneal permeability: passage of sodium fluorescein dye measured with the aid of [UV/VIS spectrophotometry / microtiter plate reader] (OD490)
- Others (e.g, pertinent visual observations, histopathology): (please specify)
After final opacity measurement, the EMEM (without phenol red) was removed from anterior chamber of each cornea holder and 1 mL of 5 mg/mL sodium fluorescein solution (in Dulbecco’s Phosphate-Buffered Saline) was added.

SCORING SYSTEM: In Vitro Irritancy Score (IVIS)

Results and discussion

In vitro

Results

Irritation parameter:

in vitro irritation score

Run / experiment:

3

Value:

171.616

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Applicant's summary and conclusion

Interpretation of results:

Category 1 (irreversible effects on the eye) based on GHS criteria

Conclusions:

In this study, the negative control (Distilled water) & positive control (Imidazole) exhibited expected response as No category (IVIS score 0.825) &
Category I (IVIS score 103.584) respectively. The test item Lithium Difluoro
(Oxalato) Borate (1-) exhibited IVIS score of 171.616.

From the results, it can be concluded as the test item Lithium Difluoro
(Oxalato) Borate (1-) has severe ocular hazard potential or compound causing serious eye damage, with the BCOP test method.

Executive summary:

The evaluation of the ocular hazard potential of Lithium Difluoro (Oxalato)
Borate (1-) was carried out using the Bovine Corneal Opacity and Permeability
test. A 0.75 mL of 20% w/v in distilled water of the test item (Lithium Difluoro
(Oxalato) Borate (1-), a 0.75 mL of 20% w/v in distilled water of positive
control (Imidazole) and a 0.75 mL of negative control (Distilled water) was
applied to each cornea by means of closed chamber method. The control and
treated corneas were then subjected to the opacity and permeability
measurements.
In this study, the negative control (Distilled water) was classified as UN GHS
No Category (IVIS score 0.825) and the positive control (Imidazole) was
classified under Category 1 (IVIS score 103.584). The test item Lithium
Difluoro (Oxalato) Borate (1-) exhibited an IVIS score of 171.616 and was
classified under UN GHS “Category 1”.
From the results, it can be concluded as the test item Lithium Difluoro
(Oxalato) Borate (1-) has severe ocular hazard potential or compound causing
serious eye damage, with the BCOP test method.