Tungsten Oxide (WO3), caesium and tin-doped

Endpoint summary

Description of key information

Under the conditions of this study, the oral LD50 value in Wistar rats was established to exceed 2000 mg/kg body weight.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

14 August 2017 to 05 September 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

2001

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

2008

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1100 (Acute Oral Toxicity)

Version / remarks:

2002

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: • Appendix to Director General Notification, No. 12-Nousan-8147. Agricultural Production Bureau, Ministry of Agriculture, Forestry and Fisheries of Japan (JMAFF)

Version / remarks:

2000

Deviations:

no

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

yes

Species:

rat

Strain:

other: Crl: WI(Han)

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Females nulliparous and non-pregnant: yes
- Age at study initiation: approximately 9-10 weeks old
- Weight at study initiation: 166 to 180 g
- Fasting period before study: Animals were deprived of food overnight (for a maximum of 20 hours) prior to dosing and until 3-4 hours after administration of the test material. Water was available.
- Housing: animals were group housed (up to 5 animals of the same sex and same dosing group together) in polycarbonate cages containing sterilized sawdust as bedding material equipped with water bottles. For psychological/environmental enrichment, animals were provided with paper.
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature: 21 to 22 °C
- Humidity: 49 to 72 %
- Air changes: Ten or greater air changes per hour with 100 % fresh air (no air recirculation) were maintained in the animal rooms.
- Photoperiod: A 12 hour light/12 hour dark cycle was maintained

Route of administration:

oral: gavage

Vehicle:

propylene glycol

Details on oral exposure:

VEHICLE
- Justification for choice of vehicle: Trial preparations were performed at the Test Facility to select the suitable vehicle and to establish a suitable formulation procedure.

MAXIMUM DOSE VOLUME APPLIED: 10 mL/kg bw

DOSAGE PREPARATION:
- Test material dosing formulations (w/w) were homogenised to visually acceptable levels at appropriate concentrations to meet dose level requirements.
- The dosing formulations were kept at room temperature until dosing. The dosing formulations and vehicle were stirred until and during dosing.
- Adjustment was made for specific gravity of the vehicle. No correction was made for the purity/composition of the test material.
- Any residual volumes were discarded.


CLASS METHOD:
- Rationale for the selection of the starting dose: The starting dose level was selected as one that is likely to produce mortality in at least some of the animals and was selected based on available toxicity data of the test material.

Doses:

2000 mg/kg body weight

No. of animals per sex per dose:

6 females per dose

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing:
Animals were observed for general health/mortality and moribundity twice daily, in the morning and at the end of the working day.
Post-dose observations were performed at periodic intervals on the day of dosing (at least three times) and once daily thereafter. All the animals were examined for reaction to dosing. The onset, intensity and duration of these signs was recorded (if appropriate). Signs were graded for severity and the maximum grade was predefined at 3 or 4. Grades were coded as slight (grade 1), moderate (grade 2), severe (grade 3) and very severe (grade 4). For certain signs, only its presence (grade 1) or absence (grade 0) was scored.
Animals were weighed individually on Day 1 (pre-dose), 8 and 15. A fasted weight was recorded on the day of dosing.
- Necropsy of survivors performed: yes. All animals surviving to the end of the observation period were sacrificed by oxygen/carbon dioxide procedure. All animals assigned to the study were subjected to necropsy and descriptions of all internal macroscopic abnormalities were recorded.

Statistics:

No statistical analysis was performed (The method used is not intended to allow the calculation of a precise LD50 value).

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality occurred

Clinical signs:

other: Hunched posture, uncoordinated movements and piloerection were noted for all animals between Days 1 and /or 2.

Gross pathology:

No abnormalities were found at macroscopic post mortem examination of the animals.

Interpretation of results:

other: Not classified in accordance with EU criteria

Conclusions:

Under the conditions of this study, the oral LD50 value in Wistar rats was established to exceed 2000 mg/kg body weight.

Executive summary:

The acute oral toxicity potential of the test material to the rat was investigated in accordance with the standardised guidelines OECD 423, EU Method B1 tris, US EPA OPPTS 870.1100 and JMAFF 12 Nousan Notification No 8147 under GLP conditions using the Acute Toxic Class Method.

The test material was administered by oral gavage to two consecutive groups of three female Wistar rats at 2000 mg/kg body weight. Animals were subjected to daily observations for 14 days and weekly determination of body weight. Macroscopic examination was performed after terminal sacrifice (Day 15).

No mortality occurred. Hunched posture, uncoordinated movements and piloerection were noted for all animals between Days 1 and/or 2. The body weight gain shown by the animals over the study period was considered to be normal. No abnormalities were found at macroscopic post mortem examination of the animals.

Under the conditions of this study, the oral LD50 value in Wistar rats was established to exceed 2000 mg/kg body weight.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Quality of whole database:

One study is available, conducted in accordance with standardised guidelines under GLP conditions. The quality of the database is therefore considered to be high.

Additional information

Oral

The acute oral toxicity potential of the test material to the rat was investigated in accordance with the standardised guidelines OECD 423, EU Method B1 tris, US EPA OPPTS 870.1100 and JMAFF 12 Nousan Notification No 8147 under GLP conditions using the Acute Toxic Class Method. The study was awarded a reliability score of 1 in accordance with the criteria set forth by Klimisch et al. (1997).

The test material was administered by oral gavage to two consecutive groups of three female Wistar rats at 2000 mg/kg body weight. Animals were subjected to daily observations for 14 days and weekly determination of body weight. Macroscopic examination was performed after terminal sacrifice (Day 15).

No mortality occurred. Hunched posture, uncoordinated movements and piloerection were noted for all animals between Days 1 and/or 2. The body weight gain shown by the animals over the study period was considered to be normal. No abnormalities were found at macroscopic post mortem examination of the animals.

Under the conditions of this study, the oral LD50 value in Wistar rats was established to exceed 2000 mg/kg body weight.

Justification for classification or non-classification

In accordance with the criteria for classification as defined in Annex I, Regulation (EC) No 1272/2008, the substance does not require classification with respect to acute toxicity via the oral route.