Registration Dossier

Administrative data

Description of key information

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Endpoint conclusion
Endpoint conclusion:
no study available

Repeated dose toxicity: inhalation - systemic effects

Link to relevant study records
Reference
Endpoint:
sub-chronic toxicity: inhalation
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Study period:
1990
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Remarks:
The EU RAR contains a review and summary of available data on HF. The studies compiled in this report were assessed as part of the EU RAR and are therefore considered to be suitably reliable. The same test was reviewed and assessed in a SCIENCE REPORT by the UK Environment Agency and also considered as reliable. Test done under GLP conditions. Read across justification is given in section 13 assessment reports: WF6 justification for read across
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 412 (Subacute Inhalation Toxicity: 28-Day Study)
Principles of method if other than guideline:
In a range-finding study, groups of five male and five female Fischer 344 rats were exposed to measured concentrations of 0, 1, 10, 25, 65 or 100 ppm (0, 0.83, 8.3, 21, 54 and 83 mg/m3) for 6 hours/day, 5 days/week, for 2 weeks; survivors were sacrificed 2 days later. 10 exposures within 15 days.
GLP compliance:
not specified
Remarks:
As per EU RAR on HF study reported to be GLP complaint.
Limit test:
no
Species:
rat
Strain:
Fischer 344
Sex:
male/female
Route of administration:
inhalation: gas
Type of inhalation exposure:
not specified
Vehicle:
air
Analytical verification of doses or concentrations:
yes
Duration of treatment / exposure:
6 hours
Frequency of treatment:
5 days/week for 2 weeks
Remarks:
Doses / Concentrations:
1 ppm (0,83 mg/m³)
Basis:
analytical conc.
Remarks:
Doses / Concentrations:
10 ppm (8,3 mg/m³)
Basis:
analytical conc.
Remarks:
Doses / Concentrations:
25 ppm (21 mg/m³)
Basis:
analytical conc.
Remarks:
Doses / Concentrations:
65 ppm (54 mg/m³)
Basis:
analytical conc.
Remarks:
Doses / Concentrations:
100 ppm (83 mg/m³)
Basis:
analytical conc.
No. of animals per sex per dose:
five male and five female
Control animals:
yes
Dose descriptor:
NOAEL
Effect level:
1 ppm (analytical)
Based on:
test mat.
Sex:
male/female
Dose descriptor:
NOAEL
Effect level:
0.83 mg/m³ air (analytical)
Based on:
test mat.
Sex:
male/female
Critical effects observed:
not specified
Conclusions:
NOAEL for HF is 1 ppm which equals 0.17 ppm of WF6 and 2.1 mg/m³ WF6 at 20 °C and 1,013 bar.
Executive summary:

In a range-finding study, groups of five male and five female Fischer 344 rats were exposed to measured concentrations of 0, 1, 10, 25, 65 or 100 ppm (0, 0.83, 8.3, 21, 54 and 83 mg/m³) for 6 hours/day, 5 days/week, for 2 weeks; survivors were sacrificed 2 days later (Placke et al, 1990). Exposures to 25 ppm (21 mg/m³) and above resulted in deaths of all females, with deaths beginning on the eighth, third, and second day of exposure at the 25, 65, and 100 ppm (21, 54 and 83 mg/m³) concentrations, respectively. Exposures to 65 and 100 ppm (54 and 83 mg/m³) resulted in deaths of all males, with deaths beginning on the third and second day at the 65 and 100 ppm concentrations, respectively. No deaths occurred during the first day of exposure at any concentration, and no deaths occurred at the lower concentrations.

Endpoint conclusion
Endpoint conclusion:
adverse effect observed
Dose descriptor:
NOAEC
2.1 mg/m³
Study duration:
subacute
Species:
rat
Quality of whole database:
Since WF6 is hydrolising rapidly to HF under ambient and physiological conditions, read across to studies on HF and NaF was done. It is turning out that the fluoride anion is inducing adverse effects, while the effect of the sodium kation or proton (Na+ or H+) is negigible. Tungsten oxides are not considered as dangerous/toxic. So, the read across data are the best possible approach to describe the properties of WF6 and its hydrolisation products.

Repeated dose toxicity: inhalation - local effects

Endpoint conclusion
Endpoint conclusion:
no study available

Repeated dose toxicity: dermal - systemic effects

Endpoint conclusion
Endpoint conclusion:
no study available

Repeated dose toxicity: dermal - local effects

Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

Justification for selection of repeated dose toxicity inhalation - systemic effects endpoint:
Most recent study under GLP conditions.

Justification for classification or non-classification

According to the UN Globally Harmonized System of Classification and Labelling of Chemicals (GHS) Part 3 WF6 is already considered to be acute toxic by inhalation: Category 2