Yttrium zirconium oxide

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

2001-02-13 to 2001-03-28

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Well documented, scientifically sound study performed according to OECD Guideline 401; however, environmental conditions were not provided.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2001

Report date:

2001

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Deviations:

no

GLP compliance:

not specified

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Yttrium zirconium oxide

EC Number:

264-885-7

EC Name:

Yttrium zirconium oxide

Cas Number:

64417-98-7

Molecular formula:

(ZrO2)x (Y2O3)y 0.59 < x < 1.0 and 0 < y < 0.41

IUPAC Name:

zirconium(4+) yttrium dioxidandiide

Test material form:

solid: particulate/powder

Details on test material:

- Name of test material (as cited in study report): zirconium oxide
- Composition: zirconium oxide containing yttrium oxide intercrystallised
- Physical state: white powder
- Stability under test conditions: stability to water and other solvent, heat, light, etc.
- Storage condition of test material: room temperature (10~30 degrees C)
- Further details on test material confidential

Test animals

Species:

rat

Strain:

other: Crj: CD (SD) IGS rat (SPF)

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Laboratories Japan, Inc.
- Age at study initiation: 5 weeks
- Weight at study initiation: 103.9-113.6 g for males and 89.0-101.2 g for females
- Fasting period before study: overnight before the administration, and for 3-4 hours after the administration
- Housing: no data
- Diet (e.g. ad libitum): no data
- Water (e.g. ad libitum): no data
- Acclimation period: no data


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


IN-LIFE DATES: From: 2001-02-20 To: 2001-03-06

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

other: purified water

Details on oral exposure:

VEHICLE
- Concentration in vehicle: no data
- Amount of vehicle (if gavage): 10 mL/kg
- Justification for choice of vehicle: no data
- Lot/batch no. (if required): A113; Takasugi Pharmaceutical Co., Ltd
- Purity: no data

MAXIMUM DOSE VOLUME APPLIED: 10 mL/kg

DOSAGE PREPARATION (if unusual): The animals were put on fasting overnight before the administration, and for 3-4 hours after the administration. The administration was done in the morning by single dose forced oral administration using flexible catheter (Terumo Corporation) and syringes (Terumo Corporation).

CLASS METHOD (if applicable)
- Rationale for the selection of the starting dose: not applicable

Doses:

2000 mg/kg

No. of animals per sex per dose:

5 male and 5 female

Control animals:

yes

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Observed all the samples frequently for up to 6 hours after the administration, then once a day for the next day to 14 days after the administration. All samples were weighed right before the administration, then 1, 3, 7, 14 days after the administration.
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight and autopsy

Statistics:

For weight, the average and the standard deviation were calculated for males and females of each group.

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Mortality:

There were no deaths in either male or female animals.

Clinical signs:

other: Ash gray stools were observed 1 day after the administration, but they disappeared in 2 days. The ash grey stools seen were considered to be a change resulting from the color of the test agent since it was white, and toxicological significance is conside

Gross pathology:

No abnormality was seen in either males or females.

Other findings:

no data

Applicant's summary and conclusion

Conclusions:

The LD50 of the test substance is higher than 2000 mg/kg body weight by the oral route in the rat.