Cobalt(II) 4-oxopent-2-en-2-olate

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2006-06-15 to 2006-07-12

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Minor deviations with no effect on the study: - According to the guideline, when no deaths occurred at 300 mg/kg then another group of three animals should be test at this dose-level of 300 mg/kg. If again no deaths occurred then a group of three animals should be test at 2000 mg/kg. When deaths occur at 2000 mg/kg (2-3 deaths) then the test item is classified in category 4 (GHS); LD50 cut off of 500 mg/kg bw. In this study first an assay with 300 mg/kg was conducted and no deaths occurred. Then an assay at 2000 mg/kg was conducted and all animals died. In a third assay the dose level 300 mg/kg was tested again. The LD50 was then recorded to be between 300 mg/kg and 2000 mg/kg. - According to the guideline, the test report must include a justification for the choice of the vehicle, if other than water. In this report no justification for the use of 0.5 % methylcellulose in purified water was given.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2007

Report date:

2007

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

2001-12-17

Deviations:

yes

Remarks:

, minor deviations with no effect on the study (see "rationale for reliability").

GLP compliance:

yes (incl. QA statement)

Test type:

acute toxic class method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Cobalt(II) 4-oxopent-2-en-2-olate

EC Number:

237-855-6

EC Name:

Cobalt(II) 4-oxopent-2-en-2-olate

Cas Number:

14024-48-7

Molecular formula:

C10H14CoO4

IUPAC Name:

cobalt(II) 4-oxopent-2-en-2-olate

Details on test material:

- Name of test material (as cited in study report): Peconal H
- Physical state: Pink powder
- Storage condition of test material: At room temperature and under argon gas

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Janvier, Le Genest-Saint-Isle, France
- Age at study initiation: approx. 8 weeks old
- Weight at study initiation: mean body weight +/- standard deviation of 206 +/- 5 g
- Fasting period before study: The animals were fasted for an overnight period of approximately 18 hours before dosing, but had free access to water. Food was given back approximately 4 hours after administration of the test item.
- Housing: The animals were housed in ploycarbonate cages with stainless steel lid (48 cm X 27 cm X 20 cm). Each cage contained one to seven animals during the acclimation period and three rats of the same group during the treatment period. Each cage contained autoclaved sawdust (SICSA, Alfortville, France.)
- Diet: All animals had free access to SsniffR/M-H pelleted diet (SSNIFF Spezialdiäten, GmbH, Soest, Germany)
- Water (ad libitum): drinking water
- Acclimation period: At least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature: 22 +/- 2 °C
- Relative humidity: 30 to 70 %
- Ventilation: approx. 12 cycles/hour of filtered, non-recycled air
- Photoperiod (hrs dark / hrs light): 12 / 12
No further information on the test animals was stated.

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

other: methylcellulose in purified water

Details on oral exposure:

VEHICLE
The vehicle used was 0.5 % methylcellulose, methylcellulose: batch No. 014K00811 (Sigma, Saint-Quentin-Fallavier, France) in purified water (prepared at CIT by reverse osmosis)

MAXIMUM DOSE VOLUME APPLIED: The dosage from preparations were administered to the animals under a volume of 10 mL/kg. The volume administered to each animal was adjusted according to body weight determined on the day of treatment.

DOSAGE PREPARATION: On the day of treatment, the test item was ground to a fine powder using a mortar and pestle, then was prepared at the chosen concentrations in the vehicle. The dosage form preparations were used within 30 minutes after preparation.

CLASS METHOD
- Rationale for the selection of the starting dose: As no information on the toxic potential of the test item was available, for animal welfare reasons, the starting dose-level of 300 mg/kg was chosen.
No further information on details on oral exposure was stated.

Doses:

300 mg/kg, 2000 mg/kg

No. of animals per sex per dose:

3 females (Since the dose-level 300 mg/kg was tested twice 6 females were test at this dose-level)

Control animals:

yes

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: The animals were observed frequently during the hours following administration of the test item, for detection of possible treatment-related clinical signs. Thereafter, observation of the animals was made at least once a day. The animals were weighed individually just before administration of the test item on day 1 and then on days 8 and 15.
- Necropsy of survivors performed: Yes, on day 15, all surviving animals wer killed by carbon dioxide asphyxiation. All study animals were subjected to a macroscopic examination as soon as possible after death. After opening the thoracic and abdominal cavities, a macroscopic examination of the main organs (digestive tract, heart, kidneys, liver, lngs, pancreas, spleen and any other organs with obvious abnormalities) was performed.
- Other examinations performed: Type, time of onset and duration of clinical signs were recorded for each animal individually. Time of death was recorded individually, in terms of the number of hours or days after dosing. Individual weights of animals found dead during the study were measured at necropsy when survival exceeded 24 hours and if no signs of "cannibalism" were present. The body weight gain of the treated animals was compared to that of CIT control animals with the same initial body weight.
No further information on details on study design was stated.

Statistics:

The interpretaiton of results was based on the flow charts of Annex 2 of the OECD Guideline No. 423, 17th December 2001 and of Annex 3 of the Directive 2004/73/EC, B.1 tris, 29th April 2004.

Results and discussion

Effect levels

Sex:

female

Dose descriptor:

LD50

Effect level:

> 300 - <= 2 000 mg/kg bw

Based on:

test mat.

Mortality:

Dose-level of 300 mg/kg (three females then confirmation on three other females):
No death occured at this dose-level.
Dose level of 2000 mg/kg (three females):
Two out three females died 2 hours after treatment and the last female was found dead on day 2.

Clinical signs:

other: Dose-level of 300 mg/kg (three females then confirmation on three other females): Hypoactivity and piloerection were observed in all the animals between 1 and 4 hours after treatment. No other clinical signs were noted thereafter, until the end of the obs

Gross pathology:

Macroscopic examination of the main organs of the animals revealed no apparent abnormalities.

Applicant's summary and conclusion

Interpretation of results:

Category 4 based on GHS criteria

Conclusions:

Under the experimental conditions, the oral LD50 of the test item Peconal H was comprised between 300 and 2000 mg/kg in rats.
According to the EC Regulation No. 1272/2008 and subsequent regulations, the test item is classified as Category 4.