Calcium sulphidoacetate

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

05 Mar 2003 - 10 July 2003

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2003

Report date:

2003

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

yes

Remarks:

ex vivo study

Principles of method if other than guideline:

The rabbit enucleated eye test is used at SPL as a first stage in the assessment of ocular irritancy potential. The preferred species of choice is the rabbit. The assay has undergone interlaboratory validation and has been shown to reliably detect test materials that are negligible, or moderate to severe ocular irritants compared to the OECD 405 guideline study.

GLP compliance:

yes (incl. QA statement)

Remarks:

Dept. of Health, UK

Test material

Test material information

Constituent 1

Reference substance name:

CaTG

IUPAC Name:

CaTG

Constituent 2

Reference substance name:

Calcium sulphidoacetate

EC Number:

249-881-5

EC Name:

Calcium sulphidoacetate

Cas Number:

29820-13-1

Molecular formula:

C2H4O2S.Ca x 3 H2O

IUPAC Name:

calcium 2-sulfanidylacetate

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

- Physical state: white powder
-The pH of the test item at the concentration of 10% in purified water was 12.2 (SPL).
- Analytical purity: 99.8%
- Lot/batch No.: 4486
- Storage condition of test material: at room temperature, in the dark and under nitrogen gas.

Test animals / tissue source

Species:

other: ex vivo rabbit eyes

Strain:

not specified

Test system

Vehicle:

water

Controls:

yes, concurrent no treatment

Amount / concentration applied:

A volume of 0.1 ml of the test material, which was found to weigh approximately 55 mg (as measured by gently compacting the required volume into an adapted syringe) was sprinkled as evenly as possible over the surface of the cornea. After ten seconds the test material was washed off the cornea using a minimum of 20 ml of saline solution (approximately 32°C). After washing, some of the test material was found to have adhered to the cornea, this did not affect the assessment of irritation or swelling.

Duration of treatment / exposure:

Immediately following washing of the corneal surface, the treated eye was returned to the superfusion chamber and the saline drip repositioned to irrigate the eye. The untreated eyes were similarly washed and used for control purposes.

Observation period (in vivo):

Assessment of corneal cloudiness was made pre-enucleation, post equilibration and approximately 60, 120, 180 and 240 minutes following treatment, according to the numerical evaluation adopted from Advances in Modern Toxicology: Dermatoxicology, 4th Ed, (F Marzulli and H Maibach, eds) Hemisphere Publishing Corporation, Washington DC, 1991, pp 749-815.

Number of animals or in vitro replicates:

Three eyes were treated with test material, two additional eyes remained untreated for control purposes. The treatment eye was removed from thesuperfusion apparatus whilst still being held in the perspex clamp. The clamp/eye was then placed horizontally into a petri dish.

Results and discussion

In vitro

Results

Results 1

Irritation parameter:

cornea opacity score

Value:

0

Vehicle controls validity:

not specified

Negative controls validity:

not specified

Positive controls validity:

not specified

Results 2

Irritation parameter:

other: Corneal Epithelium Condition

Value:

0

Vehicle controls validity:

not specified

Negative controls validity:

not specified

Positive controls validity:

not specified

Other effects / acceptance of results:

Corneal Opacity: No corneal effects were noted in the test eyes or control eyes during the study period.
Corneal thickness and Condition: Corneal swelling of the test eyes during the study period was slightly greater than that observed in the control eyes over the same period. The condition of the corneal epithelium of the test eyes and control eyes appeared normal during the study period.
Fluorescein Uptake: No fluorescein uptake was noted in the test eyes or control eyes 240 minutes after treatment.

Applicant's summary and conclusion

Interpretation of results:

Category 2 (irritating to eyes) based on GHS criteria

Conclusions:

Under the conditions of the test and following assessment of data for all end points, the test material is considered to have the potential to cause ocular irritancy in vivo. The test material is also likely to cause severe ocular irritancy in vivo in respect of its extreme alkalinity in aqueous solution.

Executive summary:

A screening study was performed to assess the ocular irritancy potential of the test material in the rabbit following application onto the cornea of the enucleated eye. The results of the study are believed to be of value in predicting the ocular irritation potential of the test material in man.

For that purpose 0.1 ml of the test material, which was found to weigh approximately 55 mg, was applied onto the cornea of each of three enucleated eyes which had been maintained at a temperature of 32°C ± 1.5°C within a superfusion chamber. A further two enucleated eyes were treated, for control purposes, with saline solution (0.9% Sodium Chloride).

 

Maximal ocular irritation observations recorded for the test eyes were as follows:

Corneal Opacity		Fluorescein Uptake		Corneal Swelling (%)						Condition of Corneal Epithelium
				Test Eyes a [min]			Control Eyes b [min]
Cldy	Area	Int	Area	60	120	240	60	120	240
0	0	0	0	11.2	12.5	20.0	3.4	3.6	3.7	Normal

a          = For each time point the swelling recorded is the mean of three eyes

b         = For each time point the swelling recorded is the mean of two eyes

Cldy = Corneal cloudiness

Int = Intensity of fluorescein uptake

[min] = Minutes following treatment

It can be concluded that under the conditions of the test, the test material is considered to have the potential to cause ocular irritancy in-vivo. The test material is also likely to cause severe ocular irritancy in-vivo in respect of its extreme alkalinity in aqueous solution.