Cesium tungsten oxide

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

13 Apr-11 May 2005

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2005

Report date:

2005

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

adopted 17 December 2001

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

Commision Directive 2004/73/EC

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

The Department of Health of the Government of the United Kingdom, London, England

Test type:

acute toxic class method

Limit test:

yes

Test material

Test material information

Constituent 1

Test material form:

solid: nanoform, no surface treatment

Test animals

Species:

rat

Strain:

Sprague-Dawley

Remarks:

CD (Crl: CD® (SD) IGS BR)

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River (UK) Ltd., Margate, Kent, UK
- Females nulliparous and non-pregnant: yes
- Age at study initiation: 8 to 12 weeks
- Weight at study initiation: 191 - 213 g (females)
- Fasting period before study: overnight
- Housing: rats were housed in groups of three in suspended solid-floor polypropylene cages furnished with woodflakes.
- Diet: Certified Rat and Mouse Diet (Code 5LF2), BCM IPS Limited, London, UK, ad libitum
- Water: mains drinking water, ad libitum
- Acclimation period: at least five days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3
- Humidity (%): 30 - 70
- Air changes (per hr): at least 15
- Photoperiod (hrs dark / hrs light): 12 hrs / 12 hrs

IN-LIFE DATES: From: 13 Apr 2005 To: 11 May 2005

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

arachis oil

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 30 mg/mL (starting) and 200 mg/mL (study)
- Justification for choice of vehicle: The test material did not dissolve/suspend in distilled water.
- Lot/batch no. (if required): batch number 050214

MAXIMUM DOSE VOLUME APPLIED: 10 mL/kg bw

DOSAGE PREPARATION: same as starting material, freshly prepared, as required

CLASS METHOD: Acute Toxic Class Method
- Rationale for the selection of the starting dose: Three fasted females were treated at a starting dose level of 300 mg/kg bw. Based on the results from this dose level further groups of fasted females were treated at a dose level of 2000 mg/kg bw.

Doses:

300, 2000 mg/kg bw

No. of animals per sex per dose:

3 females (starting)
6 females (study)

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: The animals were observed for deaths or overt signs of toxicity ½, 1, 2 and 4 hours after dosing and subsequently once daily for fourteen days. Individual bodyweights were recorded prior to dosing and seven and fourteen days after treatment.
- Necropsy of survivors performed: Yes
- Other examinations performed: No

Results and discussion

Preliminary study:

300 mg/kg bw to three fasted female rats. No clinical signs of toxicity were noted up to the end of the 14-day observation period. No mortality occurred during the study period.

Effect levels

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality occurred during the study period.

Clinical signs:

other: No clinical signs of systemic toxicity were observed up to the end of the 14-day observation period.

Gross pathology:

All animals were killed Day 14 and no abnormalities were detected at necropsy.

Applicant's summary and conclusion

Interpretation of results:

other: CLP/EU GHS criteria are not met, no classification required according to Regulation (EC) No 1272/2008

Conclusions:

The acute oral LD50 of the test substance in female Sprague-Dawley CD rats was estimated according to this OECD 423 to be greater than 2000 mg/kg bw.

Executive summary:

This study was conducted to assess the acute toxicity of the test item, following a single oral administration to small groups of rats. The study design provides information for hazard assessment and classification and enables a chemical to be assigned to toxicity classes but severely restricts animal usage.

A group of three female fasted rats were given the test item as a single dose by oral gavage at 300 mg/kg bw. Based on the results from this dose level, a further dose level at 2000 mg/kg bw was performed using 6 rats. 


The test item was dispersed in arachis oil. All animals underwent a full necropsy. No clinical, gross pathological or body weight changes were seen in the test item dosed rats. 

There were no deaths at 2000 mg/kg bw, the LD50 is considered to be > 2000 mg/kg bw.