Caesium hydroxide

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

1974

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: No GLP, equivalent or similar to OECD and EU guideline.

Cross-reference

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference 1

Reference Type:

publication

Title:

Acute toxicity of cesium and rubidium compounds

Author:

Johnson, G.T.; Lewis, R.T. and Wagner, W.D.

Year:

1975

Bibliographic source:

Toxicology and applied pharmacology 32, 239-245 (1975)

Reference 2

Reference Type:

publication

Title:

Unnamed

Year:

1972

Materials and methods

Test guideline

Test guideline 1

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

not specified

Test guideline 2

Qualifier:

equivalent or similar to guideline

Guideline:

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

Deviations:

not specified

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Caesium hydroxide

EC Number:

244-344-1

EC Name:

Caesium hydroxide

Cas Number:

21351-79-1

Molecular formula:

CsHO

IUPAC Name:

caesium hydroxide

Constituent 2

Reference substance name:

Cesium hydroxide

IUPAC Name:

Cesium hydroxide

Test material form:

solid: crystalline

Test animals / tissue source

Species:

rabbit

Strain:

other: albino

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Weight at study initiation: 2.0 to 3.0 kg

Test system

Vehicle:

water

Controls:

not specified

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied: 0.1 mL
- Concentrations: 0.1, 0.5 and 5.0 %

VEHICLE
CsOH was dissolved in deionized-distilled water on a weight-to-weight basis prior to administration.

Duration of treatment / exposure:

Single treatment for either 5 min or 24 hr before washing.

Observation period (in vivo):

21 days

Number of animals or in vitro replicates:

5 min treatment: 5 animals
24 h treatment: 3 animals
Sex not specified.

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing: Eyes were washed with a gentle, continuous stream of distilled water until a volume of approximately 250 mL was used.
- Time after start of exposure: 5 min or 24 h

SCORING SYSTEM:
Grades were assigned for the presence and/or degree of ulceration or opacity of the cornea and iris for redness (erythema), chemosis and ulceration or necrosis of the conjunctival mucosa according to the method of Draize. The eyes were examined at 1, 24, 48 , and 72 h at 7 days. If any injury persisted, the animals were re-examined at 24 and/or 21 days.

TOOL USED TO ASSESS SCORE:
The eyes were examined with the aid of fluorescein but without the aid of a hand slit-lamp.

Results and discussion

In vivo

Results

Remarks on result:

other: CsOH (5%) is considered extremely irritating and corrosive to the rabbits eye. Due to the severely of the effects no clear scores could be evaluated. 0.5 % CsOH produced no ocular reaction in the eye of rabbits.

Irritant / corrosive response data:

CsOH (5%) is considered extremely irritating and corrosive to the rabbits eye. Due to the severely of the effects no clear scores could be evaluated. Based on the marked response, an attempt was made to determine the concentration that produced no ocular reaction. 0.5 % CsOH produced no ocular reaction in the eye of rabbits.

Other effects:

One animal died in the high dose group (5%).

Applicant's summary and conclusion

Interpretation of results:

Category I

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Based in the results obtained cesium hydroxide (5%) is considered extremely irritating and corrosive to the rabbits eye. Based on the marked response, an attempt was made to determine the concentration that produced no ocular reaction. 0.5 % CsOH produced no ocular reaction in the eye of rabbits.

Executive summary:

In a primary eye irritation study, 0.1 mL of cesium hydroxide (0.1, 0.5 and 5.0 %) in water was instilled into the conjunctival sac of the eye of albino rabbits (in total eight animals) for 5 min or 24 hours. Eyes were washed with water after the exposure period. Animals then were observed for 21 days. Irritation was scored by the method of Draize. CsOH (5%) is considered extremely irritating and corrosive to the rabbits eye. Based on the marked response, an attempt was made to determine the concentration that produced no ocular reaction. 0.5 % CsOH produced no ocular reaction in the eye of rabbits.