Terbium trinitrate

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

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

Remarks:

the number of deaths at each dose were not reported; the specific doses (mg/kg) were not provided; individual clinical observations, body weights, pathology were not reported; sex of the animals was not provided.

Data source

Reference

Reference 1

Reference Type:

publication

Title:

Unnamed

Year:

1963

Reference 2

Reference Type:

secondary source

Title:

Toxicity

Author:

Haley T.J

Year:

1979

Bibliographic source:

Handbook on the Physics and Chemistry of Rare Earths, 553-585

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

GLP compliance:

no

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Terbium trinitrate

EC Number:

233-138-7

EC Name:

Terbium trinitrate

Cas Number:

10043-27-3

Molecular formula:

HNO3.1/3Tb

IUPAC Name:

terbium trinitrate

Test material form:

solid: crystalline

Details on test material:

- Name of test material (as cited in study report): Terbium nitrate
- Purity > 98%
- Other: Terbium nitrate obtained from the Lindsay Chemical Company, West Chicago, Illinois, and the K and K Laboratories, Jamaica, New York. The six hydrate form was tested (6H2O).
No other information are available.

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: No data
- Age at study initiation: adult
- Weight at study initiation: 190 g to 250 g
- Fasting period before study: no data
- Housing: Animals were housed in air-conditioned quarters
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: no data

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

Aqueous solutions (pH 4.0 - 5.9) of the rare earth nitrates were prepared immediately before injection.
The solutions were given in single doses as 50% aqueous solutions.

Doses:

Unknown

No. of animals per sex per dose:

5 or 10 animals per group

Control animals:

not specified

Details on study design:

- Duration of observation period following administration: 30 days

Statistics:

On the basis of the mortality that occurred during the 30-day observation period, the LD50 values with 95% confidence limits were calculated by the method of Litchfield and Wilcoxon (1949).

Results and discussion

Effect levels

Effect levels 1

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 5 000 mg/kg bw

Based on:

test mat.

Effect levels 2

Sex:

female

Dose descriptor:

LD50

Effect level:

> 1 753 mg/kg bw

Based on:

element

Mortality:

The animals were observed for 30 days although no deaths occurred later than 4 days after administration of the nitrate salts.

Clinical signs:

other: Within 1 to 2 hours after oral administration of the rare earth nitrates, most of the rats were depressed, and animals that received lethal doses showed little activity during the survival period.

Gross pathology:

Throughout the observation period no gross pathologic changes were noted.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The acute oral LD50 of terbium trinitrate in female rats was higher than 5000 mg/kg bw.

Executive summary:

In an acute oral toxicity study (Bruce DW et al., 1963), female Sprague-Dawley rats were given in single doses of terbium trinitrate as 50% aqueous solution and observed for 30 days.

Within 1 to 2 hours after oral administration of the rare earth nitrates, most of the rats were depressed, and animals that received lethal doses showed little activity during the survival period. The animals were observed for 30 days although no deaths occurred later than 4 days after administration of the nitrate salts. Throughout the observation period no gross pathologic changes were noted.

The acute oral LD50 of terbium trinitrate in female rats was higher than 5000 mg/kg bw.