Registration Dossier

Administrative data

Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Study period:
13 January 1982 – 4 February 1982
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Although no indication that a specific guideline was followed, the study was to GLP, and appears scientifically acceptable and well reported.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1982
Report Date:
1982

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 401 (Acute Oral Toxicity)
Deviations:
no
Principles of method if other than guideline:
A single acute oral administration of ruthenium (IV) oxide was given to rats at 2000 mg/kg bw (the highest dose causing no deaths in a range-finding study).
GLP compliance:
yes
Test type:
fixed dose procedure
Limit test:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Test material form:
solid: particulate/powder
Remarks:
migrated information: powder
Details on test material:
- Name of test material (as cited in study report): ruthenium (IV) oxide-water (1/n)
- Molecular formula (if other than submission substance): RuO2
- Substance type: black powder
- Physical state: solid
-Purity: no data
- Lot/batch No.: 061151

Test animals

Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Tuck & Sons Ltd, Battlesbridge, Essex
- Weight at study initiation: 172-225 g
- Fasting period before study: overnight (16-20 hrs) fast directly before treatment
- Housing: maximum of 5 rats (of onesex) in polypropylene cages
- Diet: ad libitum rat diet supplied by Nottingham University, School of Agriculture, Sutton Bonington, Near Loughborough, Leics
- Water: ad libitum

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3
- Air changes (per hr): minimum of 20 air changes per hr
- Photoperiod (hrs dark / hrs light): 12 hrs light, 12 hrs dark with no daylight

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
arachis oil
Details on oral exposure:
VEHICLE
- Concentration in vehicle: 100 mg/ml
- Amount of vehicle (if gavage): 0.25-20.0 ml/kg

MAXIMUM DOSE VOLUME APPLIED: 20 ml/kg
Doses:
In the range-finding study, male and female rats were administered 25, 50, 200, 500 or 2000 mg/kg bw using an all metal stomach tube. In the main study male and female rats were administered 2000 mg/kg bw.
No. of animals per sex per dose:
One rat/sex/dose in the range finding study, five rats/sex/dose in the main study.
Control animals:
no
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: ½, 1 and 4 hrs following dosing and then once daily for 14 days.
- Necropsy of survivors performed: no
- Other examinations performed: clinical signs

Statistics:
Acute oral median lethal dose (LD50)

Results and discussion

Preliminary study:
In the range-finding study, no deaths were recorded within the 5 day observation period.
Effect levels
Sex:
male/female
Dose descriptor:
LD50
Effect level:
> 2 000 mg/kg bw
Mortality:
No deaths were reported in the range-finding or the main study throughout the 5-day and 14-day observation periods respectively.
Clinical signs:
Subdued activity and pilar erection within the first hr were the only clinical effects seen.
Body weight:
Not reported.
Gross pathology:
Not reported.

Applicant's summary and conclusion

Interpretation of results:
not classified
Remarks:
Migrated information Criteria used for interpretation of results: EU
Conclusions:
In a GLP study, similar/equivalent to OECD guidelines, the acute oral LD50 of ruthenium (IV) oxide hydrate in rats was found to be greater than 2000 mg/kg bw.
Executive summary:

Ruthenium (IV) oxide hydrate was tested for its acute oral toxicity in rats, in a GLP study similar/equivalent to OECD Test Guideline 401. In a range finding study, one male and one female rat/group were administered 25, 50, 200, 500 or 2000 mg ruthenium (IV) oxide hydrate/kg bw by stomach tube. No deaths were recorded within the 5-day observation period and, therefore, in the main study, 5 rats/sex were given 2000 mg/kg bw (the highest dose causing no deaths in the range-finding study) by stomach tube. No deaths were again recorded during the 14-day observation period.

 

Based on the results of this study, ruthenium (IV) oxide should not be classified for acute oral toxicity according to EU CLP criteria (EU 1272/2008).