Potassium dicyanoargentate

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Reliable without restriction - GLP-compliant and conducted according to guideline.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2015

Report date:

2015

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 437 (Bovine Corneal Opacity and Permeability Test Method for Identifying Ocular Corrosives and Severe Irritants)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU method B.47 (Bovine corneal opacity and permeability test method for identifying ocular corrosives and severe irritants)

Test guideline 3

Qualifier:

according to guideline

Guideline:

other: INVITTOX protocol 127 (Bovine Opacity and Permeability (BCOP) Assay)

Test guideline 4

Qualifier:

according to guideline

Guideline:

other: ICCVAM and NICEATM test method March 2006 (Bovine Corneal Opacity and Permeability (BCOP))

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Potassium dicyanoargentate

EC Number:

208-047-0

EC Name:

Potassium dicyanoargentate

Cas Number:

506-61-6

Molecular formula:

C2AgN2.K

IUPAC Name:

Potassium silver(1+) cyanide (1:1:2)

Test material form:

solid: crystalline

Details on test material:

- Physical state: White crystals
- Expiration date of the lot/batch: 31 December 2015
- Storage condition of test material: Stored at room temperature.

Test animals / tissue source

Species:

other: Bovine

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: Vitelco, -'s Hertogenbosch, The Netherlands
- Age at study initiation: Bovine eyes were used as soon as possible after slaughter.
- Storage: Eyes were collected and transported in physiological saline in a suitable container under cooled conditions.
- Preparation: The isolated corneas were stored in a petri dish with cMEM (Eagle’s Minimum Essential Medium) containing 1% (v/v) L-glutamine and 1% (v/v) Foetal Bovine Serum). The isolated corneas were mounted in a corneal holder.
- Acclimation period: Minimum of 1 hour
- Temperature (°C): 32 ± 1°C

Test system

Vehicle:

physiological saline

Controls:

yes

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 750 μl
- Concentration (if solution): 20 % (w/v) potassium dicyanoargentate 54.2% in physiological saline, actual concentration of 10.84% potassium dicyanoargentate

VEHICLE
- Amount(s) applied (volume or weight with unit): 750 μl
- Concentration (if solution): physiological saline or 20% (w/v) Imidazole solution

Duration of treatment / exposure:

240 ± 10 minutes

Number of animals or in vitro replicates:

3 corneas per treatment

Details on study design:

The treatment solution was introduced onto the epithelium of the cornea and the cornea holder was maintained in a horizontal position, to ensure uniform distribution of the solutions over the entire cornea. Corneas were incubated in a horizontal position for 240 ± 10 minutes at 32 ± 1°C. After the incubation the solutions were removed and the epithelium was washed at least three times with MEM with phenol red (Eagle’s Minimum Essential Medium). The cornea was placed in fresh cMEM and opacity and permeability determinations were performed.

Results and discussion

In vitro

Results

Irritation parameter:

in vitro irritation score

Value:

65

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

other: mean irritancy score, time point: 240 min

Other effects / acceptance of results:

The corneas treated with Potassium dicyanoargentate 54.2% showed opacity values ranging from 34.0 to 51.0 and permeability values ranging from 1.131 to 1.801. The corneas were turbid after the 240 minutes of treatment with Potassium dicyanoargentate 54.2%. The in vitro irritancy scores ranged from 54.5 to 78.0, with a mean irritancy score of 65, after 240 minutes of treatment with Potassium dicyanoargentate 54.2%.

The assay is considered acceptable if:
- The positive control gives an in vitro irritancy score that falls within two standard deviations of the current historical mean.
- The negative control responses should result in opacity and permeability values that are less than the upper limits of the laboratory historical range.
All validity criteria were met.

Applicant's summary and conclusion

Interpretation of results:

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

Remarks:

Criteria used for interpretation of results: OECD GHS

Conclusions:

A 20% (w/v) solution of Potassium dicyanoargentate 54.2% which contains 10.84% potassium dicyanoargentate induced serious eye damage through both opacity and permeability, resulting in a mean in vitro irritancy score of 65 after 240 minutes of treatment.

Executive summary:

The eye hazard potential of potassium dicyanoargentate 54.2% was determined by its ability to induce opacity and increase permeability in an isolated bovine cornea. A 20% (w/v) solution of Potassium dicyanoargentate 54.2% was prepared in physiological saline, resulting in an actual concentration of 10.84% potassium dicyanoargentate. Physiological saline was used as the negative control and 20 % (w/v) imidazole served as the positive control. 750 μl of treatment solution was introduced onto the epithelium of the cornea and corneas were incubated in a horizontal position for 240 ± 10 minutes at 32 ± 1°C. Cornea opacity and permeability were assessed. Exposure to the test material induced serious eye damage through both opacity and permeability, resulting in a mean in vitro irritancy score of 65 after 240 minutes of treatment. This study is reliable without restriction as it was GLP-compliant and was performed according to guideline.