Disodium disilicate

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1987-05-26 until 1987-05-27

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP and guideline study

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1994

Report date:

1994

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Version / remarks:

adopted 1981-05-12

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.5 (Acute Toxicity: Eye Irritation / Corrosion)

Version / remarks:

of the Directive 84/449/EEC

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Disodium disilicate

EC Number:

237-623-4

EC Name:

Disodium disilicate

Cas Number:

13870-28-5

Molecular formula:

Na2Si2O5

IUPAC Name:

disodium disilicate

Details on test material:

- Name of test material (as cited in study report): Natriumschichtsilikat Na-SKS-6 kristallin
- Physical state and appearance: White powder
- Analytical purity: > 99%
- Storage condition of test material: Darkness at room temperature in a fume cupboard

Test animals / tissue source

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: HOECHST AG, Kastengrund
- Age of animals: About 3-5 months
- Animal weights: 2.8- 3.8 kg
- Housing: In fully air-conditioned rooms, separate cages (arranged in a battery)
- Diet (e.g. ad libitum): Altromin 2123 maintenance diet- rabbit (Altromin GmbH, Lage/Lippe), ad libitum and hay (approx. 15 g daily)
- Water (e.g. ad libitum): Water from automatic water dispensers, ad libitum

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20± 3°C
- Humidity (%): 50± 20%
- Photoperiod (hrs dark / hrs light): Lighting time: 12 hours daily

IN-LIFE DATES: From: 1987-05-26 To: 1987-05-27

Test system

Vehicle:

unchanged (no vehicle)

Controls:

other: The untreated eyes (the right eyes) of the 3 rabbits served in each case as a control.

Amount / concentration applied:

100 mg disodium disilicate (delta-crystalline) was applied in a single dose.

Duration of treatment / exposure:

Not indicated

Observation period (in vivo):

1 hour and 24 hours after application

Number of animals or in vitro replicates:

3 rabbits

Details on study design:

SCORING SYSTEM: As instructed by the relevant guidelines.

TOOL USED TO ASSESS SCORE: Fluorescein (one drop of 0.01% fluorescein-sodium solution).

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

cornea opacity score

Basis:

animal #1

Time point:

other: 24h

Score:

4

Max. score:

4

Reversibility:

not fully reversible within: 24h

Results 2

Irritation parameter:

cornea opacity score

Basis:

animal #2

Time point:

other: 24h

Score:

4

Max. score:

4

Reversibility:

not fully reversible within: 24h

Results 3

Irritation parameter:

cornea opacity score

Basis:

animal #3

Time point:

other: 24h

Score:

4

Max. score:

4

Reversibility:

not fully reversible within: 24h

Results 4

Irritation parameter:

cornea opacity score

Basis:

mean

Time point:

other: 24h

Score:

4

Max. score:

4

Reversibility:

not fully reversible within: 24h

Results 5

Irritation parameter:

iris score

Basis:

animal #1

Time point:

other: 1h

Score:

1

Max. score:

2

Reversibility:

not fully reversible within: 24h

Results 6

Irritation parameter:

iris score

Basis:

animal #2

Time point:

other: 1h

Score:

1

Max. score:

2

Reversibility:

not fully reversible within: 24h

Results 7

Irritation parameter:

iris score

Basis:

animal #3

Time point:

other: 1h

Score:

1

Max. score:

2

Reversibility:

not fully reversible within: 24h

Results 8

Irritation parameter:

iris score

Basis:

mean

Time point:

other: 1h

Score:

1

Max. score:

2

Reversibility:

not fully reversible within: 24h

Results 9

Irritation parameter:

conjunctivae score

Basis:

animal #1

Time point:

other: 24h

Score:

3

Max. score:

3

Reversibility:

not fully reversible within: 24h

Results 10

Irritation parameter:

conjunctivae score

Basis:

animal #2

Time point:

other: 24h

Score:

3

Max. score:

3

Reversibility:

not fully reversible within: 24h

Results 11

Irritation parameter:

conjunctivae score

Basis:

animal #3

Time point:

other: 24h

Score:

3

Max. score:

3

Reversibility:

not fully reversible within: 24h

Results 12

Irritation parameter:

conjunctivae score

Basis:

mean

Time point:

other: 24h

Score:

3

Max. score:

3

Reversibility:

not fully reversible within: 24h

Results 13

Irritation parameter:

chemosis score

Basis:

animal #1

Time point:

other: 24h

Score:

4

Max. score:

4

Reversibility:

not fully reversible within: 24h

Results 14

Irritation parameter:

chemosis score

Basis:

animal #2

Time point:

other: 24h

Score:

3

Max. score:

4

Reversibility:

not fully reversible within: 24h

Results 15

Irritation parameter:

chemosis score

Basis:

animal #3

Time point:

other: 24h

Score:

3

Max. score:

4

Reversibility:

not fully reversible within: 24h

Results 16

Irritation parameter:

chemosis score

Basis:

mean

Time point:

other: 24h

Score:

3.33

Max. score:

4

Reversibility:

not fully reversible within: 24h

Irritant / corrosive response data:

Up to 24 hours after application the conjunctivae of the animals showed swellings: The lids were about half closed and a diffuse red beefy colour appeared. Additionally, clear-colourless or white-mocous discharge were noted. One hour after application the iris of all animals was reddened.
24 hours after application the cornea of the animals showed opacity areas, the iris was invisible. The conjunctivae and the nicating membrane were discoloured white. The conjunctival sac showed severe corrosions.

Other effects:

No other effects.

Any other information on results incl. tables

Due to the severe irritation findings, the animals were killled 24 hours after application.

Applicant's summary and conclusion

Interpretation of results:

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

Remarks:

Migrated information

Conclusions:

Under the study conditions, the test substance applied to the eyes of rabbits was found to be severely irritating to the eyes.

Executive summary:

In a primary eye irritation study (study no.: 94.0713) 100 mg of the test substance disodium disilicate (delta-crystalline) was instilled into the conjunctival sac of three New Zealand albino rabbits (weight: 2.8-3.8 kg, age: 3-5 months) while the untreated eye served in each animal as a control. The study was conducted according to the OECD 405 guideline and the EG guideline B.5. Up to 24 hours after application (the eyes were examined 1 hour and 24 hours after application), the state of the eyes of all animals reached the maximum scores in most of the examined parameters. In addition, a clear- colorless or white-mucous discharge was noted and the conjunctival sac showed severe corrosions. Due to the severe irritation findings the study was terminated after 24 hours and the animals were sacrificed. The test substance is therefore considered to be severely irritating to the eyes under the test conditions, in rabbits.