Vanadium carbide nitride (V(C,N))

Endpoint summary

Description of key information

Vanadium carbide nitride is not acutely toxic via the oral, dermal, or inhalation route.

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:

2011-01-31 to 2011-03-03

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

adopted 2001-12-17

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

signed 2011-01-21

Test type:

acute toxic class method

Limit test:

no

Species:

rat

Strain:

Crj: CD(SD)

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River (UK) Ltd
- Age at study initiation: approximately eight to twelve weeks of age prior to dosing (Day 1)
- Weight at study initiation: 205 - 235 g (Day 1)
- Fasting period before study: overnight prior to and approximately four hours after dosing
- Housing: they were housed in groups of three rats of the same sex, in solid bottomed polycarbonate cages with a stainless steel mesh lid. Each cage contained a quantity of autoclaved wood flake bedding.
- Diet (ad libitum, for exception please refer to "Fasting period before study" above): standard rodent diet (Rat and Mouse No. 1 Maintenance Diet); This diet contained no added antibiotic or other chemotherapeutic or prophylactic agent.
- Water (ad libitum): potable water
- Acclimation period: at least 5 days before treatment

During the acclimatisation period, each cage of animals was provided with a soft white untreated chew block and a plastic shelter for environmental enrichment. The wood blocks were removed from the cage of animals for the same period as the food on the day prior to dosing.

ENVIRONMENTAL CONDITIONS
- Temperature: 19 to 23°C
- Relative humidity: 40 to 70%
- Photoperiod (hrs dark / hrs light): 12/12

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on oral exposure:

DOSAGE PREPARATION: the test substance was formulated at a concentration of 30 and 200 mg/mL in the vehicle and
administered at a volume of 10 mL/kg bodyweight. The test substance formulations were prepared on the day of dosing.
Formulations were mixed using a vortex mixer just before the dosing procedure.

CLASS METHOD (if applicable)
- Rationale for the selection of the starting dose: as no previous toxicological information was available the initial dose level was 300 mg/kg.

Doses:

300 and 2000 mg/kg

No. of animals per sex per dose:

6 female animals

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: cages of rats were checked at least twice daily for any mortalities. Animals were observed for clinical signs soon after dosing and at frequent intervals for the remainder of Day 1. On subsequent days, animals were observed once in the morning and again at the end of the experimental day (with the exception of Day 15 - morning only). The nature and severity, where appropriate, of the clinical signs and the time were recorded at each observation. The body weight of each rat was recorded on Days 1 (prior to dosing), 8 and 15. Individual weekly bodyweight changes and group mean bodyweights were calculated.
- Necropsy of survivors performed: yes
All animals were humanely killed on Day 15 by carbon dioxide asphyxiation.
All animals were subject to a macroscopic examination which consisted of opening the cranial, thoracic and abdominal cavities. The macroscopic appearance of all examined organs was recorded.

Statistics:

not applicable

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

other: LD50 cut off value: 5000 mg/kg bw

Mortality:

There were no deaths during the study.

Clinical signs:

other: There were no clinical signs of reaction to treatment throughout the study.

Gross pathology:

No abnormalities were noted in any animal at the macroscopic examination at study termination on Day 15.

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

LD50 (female rats) > 2000 mg/kg bw (LD50 cut off value: 5000 mg/kg bw)
According to the EC-Commission directive 67/548/EEC and its subsequent amendments, vanadium carbide nitrate is not classified as acute toxic via the oral route.
According to the EC-Regulation 1272/2008 and subsequent regulations, vanadium carbide nitrate is not classified as acute toxic via the oral route.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

discriminating dose

Value:

2 000 mg/kg bw

Quality of whole database:

The GLP study is reliable without restrictions.

Acute toxicity: via inhalation route

Link to relevant study records

Reference

Endpoint:

acute toxicity: inhalation

Data waiving:

other justification

Justification for data waiving:

other:

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Data waiving:

other justification

Justification for data waiving:

other:

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Acute oral toxicity

Vanadium carbide nitride is non-toxic if swallowed as the LD50 (rats, females) > 2000 mg/kg bw.

Acute inhalation toxicity

Due to the particle size, the test material vanadium carbide nitride can safely be assumed to have a very low potential for human inhalation hazard during handling or application. The substance is marketed in the form of briquettes with approximate dimensions up to 4 cm. In a pre-test to determine the friability, briquettes were subjected to mechanically agitation in a rotating steel drum, to simulated mechanical stress under typical industrial handling conditions. The aim of this test was to assess whether the briquettes are friable and if any fine material / dust would be abraded during typical handling conditions. The dust, i.e. friable material, as generated in the drum was subsequently tested for its potential to become airborne (modified Heubach procedure, DIN 55992-1:2006), yielding MMADs of 16.89 and 34.92 µm with GSDs of 1.10 and 4.39. On the basis of results of this dustiness test, MPPD modelling was performed and indicates that the substance does not penetrate to the deep lung tissues (tracheobronchial: 0.41%; pulmonary: 0.57%), whereas the inhaled material (Head: 51.57%) is cleared to the GI tract (by swallowing), where oral bioavailability will determine its uptake.

Acute dermal toxicity

Acute toxicity testing via the dermal route is not considered to be scientifically justified. However, following the HERAG guidance for metals and metal salts (see section 7.1.2 of the technical dossier, dermal absorption), a dermal absorption rate in the range of maximally 0.1-1.0 % can be anticipated. Dermal absorption in this order of magnitude is not considered to be “significant”.

Justification for selection of acute toxicity – oral endpoint
There is only one reliable study available.

Justification for classification or non-classification

The available information indicates that vanadium carbide nitride is not acutely toxic or harmful. Therefore, classification of vanadium carbide nitride for acute toxicity is not required according to Directive 67/548/EEC and Regulation (EC) 1272/2008.

Specific target organ toxicant (STOT) – single exposure

The classification criteria according to Regulation (EC) 1272/2008 as specific target organ toxicant (STOT) – single exposure, oral, inhalation, or dermal are not met since adverse health effects, including reversible and irreversible, were not observed immediately or delayed after exposure.