Divanadium trioxide

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1991-10-01 to 1991-11-04

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Guideline study without restrictions Minor deviations: - One concentration besides the limit dose was measured. -According to the guideline, the weight variation in animals or between groups used in a test should not exceed +/- 20 per cent of the mean weight. In the males there was a slightly larger weight variation. - According to the guideline, the relative humidity in the animal room should be between 30 - 70 % . In this study the relative humidity was slightly higher (60 +/- 20 %). -According to the guideline, animals should be tested with inhalation equipment designed to sustain a dynamic air flow of 12 to 15 air changes per hour. In this study in the high concentration group the air flow was 19.5 changes per hour. - According to the guideline, the duration of exposure should be at least 4 hours after equilibration of the chamber concentration. It was not stated if the 4 hours started after equilibration of the chamber concentration. - According to the guideline, body weight changes should be calculated and recorded when survival exceeds one days. This is missing in this study. -The GSD for the MMAD is missing.

Data source

Reference

Reference 1

Reference Type:

study report

Title:

Unnamed

Year:

1991

Report date:

1991

Reference 2

Reference Type:

publication

Title:

Unnamed

Year:

1994

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

GLP compliance:

yes (incl. QA statement)

Remarks:

The study report stated that the study was performed according to "Good Laboratory Practice" Regulations of the EEC enacted in Germany in the "Chemikaliengesetz" dated March 14th, 1990, BGBL I, pp. 521, 1990.

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Divanadium trioxide

EC Number:

215-230-9

EC Name:

Divanadium trioxide

Cas Number:

1314-34-7

Molecular formula:

O3V2

IUPAC Name:

Divanadium trioxide

Test material form:

other: solid

Details on test material:

- Name of test material (as cited in study report): Divanadium trioxide technical grade pulverised (V2O3)
- Physical state: Dark-grey, solid
- Stability under test conditions: Stable during course of study
- Storage condition of test material: Dry, in closed containers at room temperature
- Median particle sizeranges: 34 - 55 µm
No further significant information on test material was stated.

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Lippische Versuchstierzucht HAGEMANN GmbH, D-4923 Extertal 1
- Age at study initiation: 49 - 61 days
- Weight at study initiation: 197 - 270 g (males); 180 - 219 g (females)
- Fasting period before study: approx. 16 hours
- Housing: Animales were kept in groups of two or three in Makrolon cages (type III). Granulated textured wood (type 2, supplied by Johannes Brandenburg, D-4937 Goldenstedt) was used as bedding material.
- Diet (ad libitum): Standardized diet for rats ALTROMIN 1324 (supplied by: ALTROMIN GmbH, D- 4937 Lage/Lippe)
- Water (ad libitum): tap water
- Quarantine period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature: 22 °C +/- 3 °C (maximum range)
- Relative humidity: 60 % +/- 20 % (maximum range)
- Photoperiod (hrs dark / hrs light): 12/12
No further significant information on test animals was stated.

Administration / exposure

Route of administration:

inhalation: dust

Type of inhalation exposure:

nose only

Vehicle:

other: air

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus & Exposure chamber volume: The study was carried out using a dynamic inhalation apparatus with a nose only exposure of the animals according to KIMMERLE & TREPPER (Rhema-Labortechnik, D-6238 Hofheim/Taunus). The apparatus consists of a cylindrical exposure chamber (volume 40 l) which holds a maximum of 20 animals in pyrex tubes at the edge of the chamber in a radial position.

- Source and rate of air: At the bottom of the exposure chamber the air was sucked off at the similar rate as created by the dust generator in order to produce a homogenous distribution in the exposure chamber. Air-flow meters (Rotameter, ROTA Apparate- und Maschinenbau, D-7867 Wehr 2/Baden) were used to control the constant supply of compressed air and vacuum. Flow rates were checked at least once/hour and corrected if necessary. Air flow was 480 l/h for the low concentration, and 780 l/h for the high concentration. The air change was 12.0 changes per hour for the low concentration, and 19.5 changes per hour for the high concentration.

- System of generating particulates/aerosols: The dust was generated with a dust generator and dosing apparatus (BURGHART, D-2000 Wedel/Holstein). The generator was fed with compressed air from a compressor.

- Method of particle size determination: An analysis of the particle size distribution was carried out twice during the exposure period using a cascade impactor according to MAY (1975).
The impactor is a device that classifies particles present in a sample of air or gas into known size ranges. It does this by drawing the air sample through a cascade of progressively finer nozzles. The air jets from these impact on plane sampling surfaces (slides) covered with adhesive tape. Each stage represents an aerodynamic size range. The dust from the exposure chamber was sucked through the cascade impactor for 1 0r 2 minutes at a constant flow rate of 5 l/min. The slides were removed from the impactor and were weighed on an analytical balance (SARTORIUS, type 1601004, precision 10µg).
Respirable amount (particle size <= 4 µm)
Dose level 1.58 mg/l air: 0.30 mg/l air
Dose level 6.65 mg/l air: 0.74 mg/l air

- Temperature, humidity: The temperature (GTH 1200 Digital Thermometer, Fa. Greisinger Electronic GmbH, D-8413 Regenstauf) and humidity (Sekunden -Hygrometer Typ 6100, Testoterm) was continuously monitored close to the animals' nose in the inhalation chamber. The temperature was 19 °C - 21 °C and the relative humidity was 60 % - +/- 20 %.

TEST ATMOSPHERE (Test substance concentration)
- Brief description of analytical method used: The dust concentration in the inhalation chamber was measured with an air sample filter (Minisart SM 17598) and pump (water jet air pump controlled by a rotameter). Dust samples were taken during the first half and during the second half of the exposure. The Minisart SM 17598 filters were placed close to the animals' nose and sucked through with a constant flow of air of 300 l/h for 1 or 2 minutes with a water jet air pump controlled by a rotameter. The filters were weighed before and after sampling (accuracy 0.01 mg).
- Samples taken from breathing zone: yes/no

TEST ATMOSPHERE
- Particle size distribution: The sample supplied had a particle size distribution of 70.6 % in the particle size range of 23.7 to 54.9 µm measured with a Malvern particle sizer.
Particle size (µm) and mean (concentration 1.58 mg/l air):
<0.5 µm: 0.06 %
0.5 µm: 2.59 %
1 µm: 5.73 %
2 µm: 9.78 %
4 µm: 19.19 %
8 µm: 32.69 %
16 µm: 56.71 %
>= 32 µm: 100.0 %
Particle size (µm) and mean (concentration 6.65 mg/l air):
<0.5 µm: 0.67 %
0.5 µm: 2.34 %
1 µm: 4.71 %
2 µm: 9.43 %
4 µm: 11.10 %
8 µm: 21.75 %
16 µm: 60.62 %
>= 32 µm: 100.0 %
- MMAD:
Dose level 1.58 mg/l air: 15.14 µm
Dose level 6.65 mg/l air: 19.48 µm
No further significant information on inhalation exposure was stated.

Analytical verification of test atmosphere concentrations:

yes

Remarks:

see "details on inhalation exposure" above

Duration of exposure:

4 h

Remarks on duration:

Exposition started by locating the rats into the exposure chamber.

Concentrations:

Mean actual concentration: 1.58 +/- 0.11 mg/l air (nominal concentration: 8.1 mg/l air) and 6.65 +/- 2.11 mg/l air (nominal concentration: 35.1 mg/l air). 6.65 mg/l air was the highest concentration that could be generated in the inhalation chamber. Since neither mortalitiy nor toxic symptoms were observed up to the concentration of 6.65 mg/l air for 4 hours, no higher dosage was applied.

No. of animals per sex per dose:

5 males / 5 females

Control animals:

not specified

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: During and following exposure, observations were made. A careful clinical examination was made at least once each day until all symptoms subsided, thereafter each working day. Observations on mortality were made at least once daily with appropriate actions taken to minimize loss of animals to the study. Individual body weights of the animals were determined before the exposure, after 1 week and at study termination.
- Necropsy of survivors performed: Yes, necropsy of all animals was carried out and all gross pathological changes were recorded. From animals which survived 24 hours or longer a microscopic examination of all organs which showed evident lesions was performed after preparation of paraffin sections and HE-staining.
- Other examinations performed: clinical signs, body weight,organ weights, histopathology, other: Cageside observations included, but were not limited to, changes in the skin and fur, eyes, mucous membranes, respiratory, circulatory, autonomic and central nervous system, and somatomotor activity and behaviour pattern. Particluar attention was directed to observation of tremors, convulsions, salivation, diarrhoea. lethargy, sleep and coma.
No further significant information on study design was stated.

Statistics:

The mass median aerodynamic diameter (MMAD) was estimated by means of nonlinear regression analysis (LITCHFIELD & WILCOXON). The 32 µm particle size range was not included in the determination of the MMAD in order not to give undue weight to this value.The LC50 could not be calculatedbecause no mortality occurred.

Results and discussion

Effect levels

Effect levels 1

Sex:

male

Dose descriptor:

LC50

Effect level:

> 6.65 mg/L air

Exp. duration:

4 h

Effect levels 2

Sex:

male

Dose descriptor:

LC0

Effect level:

> 6.65 mg/L air

Exp. duration:

4 h

Effect levels 3

Sex:

female

Dose descriptor:

LC50

Effect level:

> 6.65 mg/L air

Exp. duration:

4 h

Effect levels 4

Sex:

female

Dose descriptor:

LC0

Effect level:

> 6.65 mg/L air

Exp. duration:

4 h

Mortality:

Under the present test conditions no mortalitiy was observed up to 6.65 mg V2O3 technical grade pulverised/l air for 4 hours.

Clinical signs:

other: Dose level & toxic signs: 1.58 mg/l air: No signs of systemic intolerance 6.65 mg/l air: No signs of systemic intolerance 5.2 mg/l air: except for mortality, no signs of systemic intolerance

Body weight:

There was no inhibition of body weight gain in either males or females.

Any other information on results incl. tables

	1.58 mg/l air	1.58 mg/l air	6.65 mg/l air	6.65 mg/l air
Lungs	male	female	male	female
macroscopic-number examined	5	5	5	5
white foci	0	0	1	0
haemorrhagic	1	2	0	2
microscopic-number examined	1	1	1	1
vascular congestion	0	1	1	1
initial haemorrhagic bronchopneumania	1	1	0	0

The histopathological changes found in the lung were regarded as unspecific effects, which usually occur after an inhalative exposure to a dust.

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

No acute toxicity was observed in an 4-h acute toxicity inhalation test of V2O3 in rats (LD50 > 6.65 mg/L), Thus, according to Regulation 83/467/EEC, V2O3 (technical grade pulverised) will not be classified for acute toxicity via inhalation.