Tellurium

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1996-01-31 to 1996-02-16

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1996

Report date:

1996

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

GLP compliance:

yes (incl. QA statement)

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Tellurium

EC Number:

236-813-4

EC Name:

Tellurium

Cas Number:

13494-80-9

Molecular formula:

Te

IUPAC Name:

hydrogen telluride

Test material form:

solid: particulate/powder

Details on test material:

- Name of test material (as cited in study report): Tellurium
- Substance type: inorganic
- Physical state: fine grey powder
- Analytical purity: > 99.5 %
- Lot/batch No.: GI1631/95
- Storage condition of test material: ambient

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Wiga, Sulzfeld, Germany
- Age at study initiation: 5 - 6 weeks old upon arrival
- Weight at study initiation:
- Fasting period before study: overneight
- Housing: five animals per cage (stainless steel cages, fitted with wire screen floor and front)
- Diet (e.g. ad libitum): standard laboratory rat diet ad libitum
- Water (e.g. ad libitum): Tap water ad libitum.
- Acclimation period: 21 - 23 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3°C
- Humidity (%): between 32. 5 - 80 %
- Air changes (per hr): ca 10 air changes/hour
- Photoperiod (hrs dark / hrs light): 12 hours Iight/12 hours dark cycle

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

maize oil

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 50 % w/v
MAXIMUM DOSE VOLUME APPLIED: 10 mL/ kg max. Dose volume

Doses:

5000 mg/kg bw

No. of animals per sex per dose:

5 animals/ sex/ dose

Control animals:

no

Details on study design:

A screening was carried out with two females treated with a dose level of 5000 mg/kg body weight to check for mortality. Since no mortality was observed, the study was continued with three females and five males which were treated with the same dose level. All animals were dosed with a 500 mg/mL suspension in maize oil and a 10mL/kg body weight dosing volume.

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: observations were made within 1 hour and within 4 hours after dosing, and subsequently at least once daily throughout the observation period of 14 days; body weights were recorded on day 0, 3, 7 and 14.
- Necropsy of survivors performed: yes

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 5 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality occured during the 14-day observation period.

Clinical signs:

other: No clinical symptoms were observed.

Gross pathology:

Examination of the animals at autopsy did not reveal any treatment-related gross alterations.

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: other: EU GHS (Regulation (EC) No 1272/2008)

Conclusions:

The LD50 for tellurium (powder) was determined to be above 5000mg/kg bw .

Executive summary:

This acute oral toxicity study was conducted according to OECD Guideline 401 (Acute Oral Toxicity). A screening was carried out with two female Wistar rats treated with a dose level of 5000 mg/kg bw to check for mortality. Since no mortality was observed, the study was continued with three females and five males which were treated with the same dose level and observed for 14 days.

No clinical symptoms were observed and no mortality occurred during the 14-day observation period. All animals gained weight during the 14-day observation period.

Examination of the animals at autopsy did not reveal any treatment-related gross alterations.

Since no mortality occurred during the 14-day observation period, the oral LD₅₀of tellurium is considered to exceed 5000 mg/kg bw in both male and female rats.