Yttrium trinitrate

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 1991-01-29 to 1991-02-28

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1991

Report date:

1991

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

other: Code of Federal Regulations 16: 1500.3

Deviations:

not specified

Test guideline 2

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Deviations:

no

GLP compliance:

not specified

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Yttrium trinitrate

EC Number:

233-802-6

EC Name:

Yttrium trinitrate

Cas Number:

10361-93-0

Molecular formula:

N3O9Y

IUPAC Name:

yttrium trinitrate

Test material form:

solid: particulate/powder

Details on test material:

- Name of test material (as cited in study report): Yttrium nitrate
- Substance type: Off-white crystalline/powdered solid
- Physical state: Solid
- Further information on test material confidential.

Specific details on test material used for the study:

The sample was tested as a 50% w/w solution in distilled water. The gravity of the test material was 1.406 (dosage of 1.25 g/kg), 1.382 (dosage of 2.5 g/kg) and 1.354 (dosage of 5.0 g/kg).

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Hilltop Lab Animals, Scottdale, PA, USA
- Age at study initiation: no data
- Weight at study initiation: male: 208-225 g; female: 202-221 g
- Fasting period before study: approximately 18 hours prior to selection and test initiation
- Housing: individually in suspended stainless steel caging with mesh floors
- Diet (e.g. ad libitum): pelleted purina rat chow ad libitum from 1 h after dosing
- Water (e.g. ad libitum): tap water ad libitum
- Acclimation period: 5, 6 or 12 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18.9 to 22.2°C
- Humidity (%): no data
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): no data

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Remarks:

distilled water

Details on oral exposure:

VEHICLE
- Concentration in vehicle: The sample was tested as a 50% w/w solution in distilled water.
- Dosing volumes: 1.78 mL/kg (1250 mg/kg); 3.62 mL/kg (2500 mg/kg); 7.43 mL/kg (5000 mg/kg)

Doses:

1250, 2500 and 5000 mg/kg
Data for the highest dose came from a limit test.

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: The rats were observed at approximately 1, 2 and 4 hours after dosing and at least once daily thereafter for signs of gross toxicity and mortality. Body weights were recorded initially, at termination (day 14) or after death.
- Necropsy of survivors performed: Yes, necropsies were performed on all decedents.

Statistics:

The LD50 was calculated by the Litchfield-Wilcoxon Method of Probit Analysis or estimated graphically.

Results and discussion

Effect levels

Effect levels 1

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

1 650 mg/kg bw

Based on:

test mat.

95% CL:

1 240 - 2 190

Effect levels 2

Sex:

male

Dose descriptor:

LD50

Effect level:

2 000 mg/kg bw

Based on:

test mat.

95% CL:

1 570 - 2 540

Effect levels 3

Sex:

female

Dose descriptor:

LD50

Effect level:

1 300 mg/kg bw

Based on:

test mat.

Remarks on result:

other: estimated graphically

Mortality:

1250 mg/kg: 20% mortality occurred by day 2
2500 mg/kg: 90% mortality occurred by day 2
5000 mg/kg: 100% mortality occurred by day 3

Clinical signs:

other: 1250 mg/kg: Following test material administration, all animals appeared lethargic and had a hunched posture. All surviving animals recovered from the above toxic signs by day 3. 2500 mg/kg: Following test material administration, all animals appeared let

Gross pathology:

1250 mg/kg: Necropsy of the decedents revealed distention of the stomach with discoloration of the pyloric region and intestines.
2500 mg/kg: Necropsy of the decedents revealed distention of the stomach, with discoloration of the pyloric region and intestines.
5000 mg/kg: Necropsy of the decedents revealed distention of the stomach with a cloudy white fluid and discoloration of the intestines. The two animals which died after day 1 also exhibited discoloration of the lungs and liver.

Other findings:

No data

Applicant's summary and conclusion

Interpretation of results:

Category 4 based on GHS criteria

Conclusions:

The acute oral LD50 calculated by Probit analysis was 1650 mg/kg with 95% confidence limits of 1240 to 2190 mg/kg for male and female animals. Therefore the substance is considered classified as category 4 (H302) according to the criteria of the CLP Regulation.