Calcium sulfate

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Not specified

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study was performed according to internationally accepted testing guidelines.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1990

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

no

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Calcium sulfate

EC Number:

231-900-3

EC Name:

Calcium sulfate

Cas Number:

7778-18-9

Molecular formula:

CaSO4

IUPAC Name:

calcium sulfate

Details on test material:

- Name of test material (as cited in study report): Calcium sulfate anhydrite
- Analytical purity: 92.9%
- Lot no: 7439
- Storage condition of test material: Kept at room temperature in the dark.

Test animals / tissue source

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: provided by Granjas Jordi.
- Age at study initiation: ~ 12 weeks
- Weight at study initiation: 2.2 - 2.7 kg
- Housing: The rabbits were accommodated individually in stainless steel cages with rack floors
- Diet: Rabbit standard diet ad libitum
- Water : Water available ad libitum



ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19 ± 2ºC
- Humidity (%): 46 - 70 %
- Photoperiod (hrs dark / hrs light): 12 h of light and 12 h of dark every 24 h

Test system

Vehicle:

not specified

Controls:

other: One eye in each rabbit was treated, with the other eye remaining as a control.

Amount / concentration applied:

100 mg of anhydrite was applied to each animal.

Duration of treatment / exposure:

A single dose of anhydrite was applied to each animal. The animal was immobilised for the application and the product was placed in the conjunctival sac of the right eye, which was perfectly accessible by gently pulling the lower lid away from the eyeball.

Observation period (in vivo):

The behaviour of the animals was observed immediately after the product instillation and then they were returned to their cages. The grade of eye irritation was evaluated for every rabbit 1, 24, 48 and 72 h after the treatment.
After 24 h further corneal observations were performed by the instillation of a 2 % aqueous solution of fluorescein sodium, The aqueous solution was intilled on the test area, washing this with a physiological solution. Once the excess fluorescein was removed, the corneal alterations were observed with the aid of a transiluminator fitted with a cobalt blue filter.

Number of animals or in vitro replicates:

3

Details on study design:

The lids of the treated eye were then hed together for about 1 sec. The left eye was untreated and served as a control. Immediately after the product instillation, the rabbits were kept with a plastic collar for 1 h so that they could not rub their eyes.
In order to facillitate the evaluation of the eye alterations, the document "Illustrated Guide for Grading Eye Irritation by Hazardous Substances", was used, edited by Superintendent Documents, Government Printing Office, Washington D. C. USA.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

cornea opacity score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

4

Results 2

Irritation parameter:

cornea opacity score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

4

Results 3

Irritation parameter:

cornea opacity score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0.33

Max. score:

4

Reversibility:

fully reversible within: 48 hrs

Results 4

Irritation parameter:

iris score

Basis:

mean

Remarks:

all animals

Time point:

24/48/72 h

Score:

0

Max. score:

2

Reversibility:

fully reversible within: 24 hrs

Results 5

Irritation parameter:

conjunctivae score

Basis:

animal #1

Time point:

24/48/72 h

Score:

1

Max. score:

4

Reversibility:

not fully reversible within: 72 hrs

Results 6

Irritation parameter:

conjunctivae score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0.33

Max. score:

4

Reversibility:

fully reversible within: 48 hrs

Results 7

Irritation parameter:

conjunctivae score

Basis:

animal #3

Time point:

24/48/72 h

Score:

1

Max. score:

4

Reversibility:

not fully reversible within: 72 hrs

Results 8

Irritation parameter:

chemosis score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

fully reversible within: 24 hrs

Results 9

Irritation parameter:

chemosis score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0.33

Max. score:

4

Reversibility:

fully reversible within: 48 hrs

Results 10

Irritation parameter:

chemosis score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0.33

Max. score:

4

Reversibility:

fully reversible within: 48 hrs

Irritant / corrosive response data:

The substance anhydrite induced, 1 h after the instillation, blood vessels of a diffused crimson colour (grade 2) in the conjunctivae, accompanied by obvious swelling with partial eversion fo the eyelids (grade 2) and slight lacrimation (grade 1). One rabbit also showed an area of diffuse opacity in the cornea. All the animals showed irridial lesions (grade 1).
24 h after the treatment, blood vessels of a diffused crimson colour (grade 2) in the conjunctivae were observed in one animal and blood vessels clearly hyperaemic (grade 1) were observed in the other two. Two rabbits showed slight eyelid swelling (grade 1). One rabbit also showed an area of opacity in the cornea (grade 1) that covered less than a quarter of it.
48 h after application, two animals showed hyperaemia (grade 1).
72 h after instillation, only one animal showed blood vessels slightly hyperaemic (grade 1) in the conjunctivae.

Other effects:

The behaviour and physical condition of the rabbits were normal during the whole study; there were no mortalities.

Any other information on results incl. tables

Table 1: Observations of ocular alterations after administration:

Animal No.	Region of the eye	1 h	24 h	48 h	72 h
951	Cornea	0	0	0	0
	Iris	1	0	0	0
	Conjunctiva: Hyperemia	2	1	1	1
	Conjunctiva:Edema	2	0	0	0
973	Cornea	0	0	0	0
	Iris	1	0	0	0
	Conjunctiva: Hyperemia	2	1	0	0
	Conjunctiva:Edema	2	1	0	0
593	Cornea	1	1	0	0
	Iris	1	0	0	0
	Conjunctiva: Hyperemia	2	2	1	0
	Conjunctiva:Edema	2	1	0	0

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Calcium sulfate is not irritating to eyes