Caesium sulphate

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2011-03-24 to 2011-04-13

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP and guideline compliant

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2011

Report date:

2011

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.1 tris (Acute Oral Toxicity - Acute Toxic Class Method)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test type:

acute toxic class method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Caesium sulphate

EC Number:

233-662-6

EC Name:

Caesium sulphate

Cas Number:

10294-54-9

Molecular formula:

Cs.1/2H2O4S

IUPAC Name:

caesium sulphate

Test material form:

solid: crystalline

Test animals

Species:

rat

Strain:

other: Crl(WI)Br

Sex:

female

Details on test animals or test system and environmental conditions:

Test animals
- Source: Toxi-Coop Zrt. 1103 Budapest, Cserkesz u. 90.
- Age at study initiation: young adult rats, 11/12 weeks old
- Weight at study initiation: 223-229 g
- Fasting period before study: food but not water was withheld overnight
- Housing: 3 animals/sex/cage
- Diet: ad libitum (ssniff® SM R/M-Z+H complete diet)
- Water: ad libitum
- Acclimation period: 35 days in first step, 36 days in second step and 40 days in third step

ENVIRONMENTAL CONDITIONS
- Temperature: 22 ± 3 °C
- Humidity: 30 - 70 %
- Air changes: 8 - 12 air exchanges/hour by central air-condition system
- Photoperiod: artifical light, from 6 a.m. to 6 p.m.

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

physiological saline

Control animals:

no

Details on study design:

Testing Procedure
A single oral administration - followed by a fourteen-day observation period - was performed by gavage. The day before treatment the animals were
fasted. The food but not water was withheld overnight. Animals were weighed before the application and the food was given back 3 hours after the treatment.

Dose Level
Starting dose was selected on the basis of the available information about the test item.
The acute toxic class method was carried out involving a stepwise procedure with the use of 2000 mg/kg bw as the starting dose in three female rats.

Observations
Mortality
Inspection for signs of morbidity and mortality were made twice daily at the beginning and end of the working day.
Clinical Observations
Individual observations were performed on the skin and fur, eyes and mucous membranes and also respiratory, circulatory, autonomic and central nervous system, somatomotor activity and behaviour pattern. Particular attention was directed to observation of tremors, convulsions, salivation, diarrhoea, lethargy, sleep and coma.
Body weight
The body weight were recorded on day 0 (shortly before the treatment), at day 7 and at day 15 on all animals with a precision of 1 g.
Pathology
All animals were subjected to gross pathology. All animals were exsanguinated under isoflurane anaesthesia. After examination of the external appearance the cranial, thoracic and abdominal cavities were opened and the appearance of the tissues and organs were observed. All gross pathological changes were recorded for each animal on the post mortem record sheets.

Results and discussion

Effect levels

Sex:

female

Dose descriptor:

LD50

Effect level:

> 300 - < 2 000 mg/kg bw

Based on:

test mat.

Mortality:

All rats dosed at 2000 mg/kg Cesiumsulfat 99,99 died between the treatment day and Day 1.
No death occurred at 300 mg/kg single oral dose of the test item. All rats survived until the end of the 14-day observation period.

Clinical signs:

other: 2000 mg/kg bw: In group 1 treated with 2000 mg/kg dose clinical sign of reaction comprised of decreased activity and general reaction (14 cases out of 14 observations), prostration (10/14), clonic convulsion (1/14), decreased righting reflex (8/14), decre

Gross pathology:

All rats treated with 2000 mg/kg dose of the test item spontaneously died during the study. There was no any macroscopic alteration in died animals.
All animals treated with 300 mg/kg dose of test item survived until the scheduled necropsy on Day 15. Slight hydrometra was found in two females of the group 3. Hydrometra is physiological finding and connected to the cycle of the animal. No pathological changes were found related to the effect of the test item during the macroscopic examination of animals.

Applicant's summary and conclusion

Interpretation of results:

Toxicity Category IV

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The acute oral LD50 obtained for the test item was found to be between 300 and 2000 mg/kg bw. Therefore, the test item is classified as category 4 according to Regulation (EC) No 1272/2008 (CLP/GHS).

Executive summary:

This study was conducted to assess the acute oral toxicity of the test item in Rats (Crl(WI)Br) according to OECD Guideline 423 and EU Method B.1 tris. The acute toxic class method was carried out involving a stepwise procedure with the use of 2000 mg/kg bw as the starting dose in three female rats. Since three female animals died the test was continued at 300 mg/kg bw dose level on further three female rats. No animal died in the second step at 300 mg/kg bw dose level, three further female rats were treated with the same (300 mg/kg bw) dose. No animal died in the third step, too, so the test was finished, the stopping criteria of Annex 2d of OECD Guideline No. 423 (presented in Annex VII) were met. Animals were weighed, observed for lethality and toxic symptoms for 14 days after the treatment. Gross pathological examination was carried out on the 15th day after the treatment.

According to the results from this study the LD50 obtained for the test item was found to be between 300 and 2000 mg/kg bw. Therefore, the test item is classified as category 4 according to Regulation (EC) No 1272/2008 (CLP/GHS).