Tungsten trioxide

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2002-07-02 to 2002-08-20

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Well documented, scientifically sound study that was conducted in accordance with GLP and OECD Guideline 423, limit test.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2002

Report date:

2002

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Tungsten trioxide

EC Number:

215-231-4

EC Name:

Tungsten trioxide

Cas Number:

1314-35-8

Molecular formula:

O3W

IUPAC Name:

trioxotungsten

Details on test material:

- Name of test material (as cited in study report): Tungsten oxide (WO3)
- Physical state: Yellow to greenish powder
- Analytical purity: 99.88%
- Purity test date: 2002-05-28
- Stability under test conditions: 5 years
- Storage condition of test material: Ambient temperature, dry
- Melting Point: Approx. 1473 degrees C
- pH: 6.1 (aqueous suspension, 100 g/L)
- Solubility in water: <10 mg/L WO3

Test animals

Species:

rat

Strain:

other: Crl:CD(SD)IGS BR

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River WIGA
- Age at study initiation: Approximately 8 weeks
- Weight at study initiation: 166-167 g (females), 195-201 (males)
- Fasting period before study: Yes; the feed was withdrawn the evening before the administration of the test substance and was offered again about three hours afterwards.
- Housing: Single caging in Makrolon cages type III (39 cm x 23 cm bottom area, 18 cm height). Wire mesh lids. Sanitation of cages once a week.
- Diet: Altromin 1324 forte, gamma irradiated with 25 kGy60Co, ad libitum.
- Water: Tap water from an automatic watering system, ad libitum.
- Acclimation period: At least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): average of 22.2 °C
- Humidity (%): Average of 64.7%
- Air changes (per hr): 12/hr
- Photoperiod (hrs dark / hrs light): 12 dark/12 light (6 am to 6 pm)

IN-LIFE DATES: From: 2002-07-02 To: 2002-07-17

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

DOSE VOLUME APPLIED: 10 mL /kg body weight

DOSAGE PREPARATION: Doses of 2000 mg/kg body weight were prepared as suspensions in deionised water. Suspensions were prepared freshly before administration and were administered within 5 minutes after the preparation.

CLASS METHOD (if applicable)
- Rationale for the selection of the starting dose: As requested by the sponsor

Doses:

2000 mg/kg body weight (in two steps)

No. of animals per sex per dose:

3 males and 3 females

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing:
- Clinical observations- 0-0.5, 0.5-1, 1-2, 2-4, and 4-6 hours after administration and then at least once a day for a total of 2 weeks. Observations included but were not limited to changes in skin, fur, eyes, the occurrence of secretions and excretions, autonomic activity, changes in gait, posture and the presence of convulsions.
- Body weights- before administration, day 7, and day 14 post administration. Bodyweight gain was calculated for each week of the study, i.e. between 0 and 7 days post administration and 7 and 14 days post administration.
- Necropsy of survivors performed: Yes

Statistics:

no data

Results and discussion

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Remarks on result:

other: No toxic effects were present after a single dose of 2000 mg/kg of the test substance.

Mortality:

None

Clinical signs:

other: All animals were normal during the whole observation period.

Gross pathology:

All animals were normal at the necropsy, 14 days post administration.

Other findings:

There was no significant sex difference in the response to the test substance at 2000 mg/kg body weight.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

No toxic effects of the test substance were noted by signs in life and post mortem. No mortality occurred. An LD50 of > 2000 mg/kg body weight for rats was established for the test substance.