Cobalt molybdate

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Jul. 30 - Sep. 10, 2015; experimental phase: Aug. 4-19, 2015

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2015

Report date:

2015

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Version / remarks:

1987

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 434 (Acute Dermal Toxicity - Fixed Dose Procedure)

Version / remarks:

2004

GLP compliance:

yes (incl. QA statement)

Test type:

fixed dose procedure

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Cobalt molybdate

EC Number:

237-358-4

EC Name:

Cobalt molybdate

Cas Number:

13762-14-6

Molecular formula:

CoMoO4

IUPAC Name:

λ²-cobalt(2+) dioxomolybdenumbis(olate)

Details on test material:

- Name of test material (as cited in study report): cobalt molybdenum oxide
- Physical state: light green powder
- Analytical purity: 99%
- Batch No.: EH 110005/1
- Expiration date of the lot/batch: June 2013
- Storage condition of test material: The test item was stored in a closed vessel at room temperature.

Specific details on test material used for the study:

Test Item: Cobalt Molybdenum Oxide
Lot Number: EH 110005/1
Certificate: Test Item Specification of LAUS GmbH
Manufacturer: Grace GmbH & Co. KG
Appearance: Light green powder
Composition: 99 % Cobalt (II) molybdenum oxide

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

Source: Velaz Prague, Czech Republic
Age at First Dose: 8-12 weeks; female animals were non-pregnant and nulliparous
Animal Health: The health condition of animals was examined by a veterinarian before initiation of the study.
Acclimation: The animals were acclimated to the condition identical to the conditions during the experiment 5 days prior to the start of treatment. The acclimation was according to the standard operation procedure.
Housing Condition: The animals were housed in plastic cages suspended on stainless steel racks, up to 2-3 animals per cage, males and females separately in a room equipped with central air-conditioning. The room temperature was maintained within the range of 22 ± 2° C, relative humidity within 55 ± 10 %. The light regimen was set to a 12-hour light /12-hour dark cycle. The sanitation was performed according to the standard operation procedures.
Diet: A laboratory food Altromin (Altromin Spezialfutter GmbH, Germany) was offered in recommended doses each day approximately at the same time. The certificate of analysis is included in the raw data.
Water: The animals received tap water for human consumption. Supply of drinking was unlimited. The quality of drinking water is periodical analysed (including microbiological control) and recorded; certificate of analysis is included in raw data.
Bedding: Lignocel S3/4, Lufa - ITL GmbH, Germany

Administration / exposure

Type of coverage:

semiocclusive

Vehicle:

CMC (carboxymethyl cellulose)

Details on dermal exposure:

Approximately 24 hours before the test, fur was removed from the dorsal area of the trunk of the test animals by clipping and shaving. A precise amount of the test item was aspirated into an adjustable pipette and application directly on the shaved skin of back in a single dose uniformly on
over an area approximately 10 % of the total body surface area. Test item was held in contact with the skin by using a Cosmopor E and a semi-occlusive dressing with non-irritating tape throughout the 24-hours exposure period. At the end of the exposure period, any residuals of the test item were removed by using lukewarm water without altering the existing response or integrity of the epidermis.

Duration of exposure:

24 h

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

5

Control animals:

not required

Details on study design:

Available information indicated test item is likely to be nontoxic considering to acute toxicity. Therefore, a limit dose of 2000 mg/kg was used as starting dose. One female was dosed. Test item-related mortality was not produced during 24-hours exposure period. The sighting study was finished; the main test was started with dose of 2000 mg/kg. An additional 4 females and 5 males were dosed in the Main Study with the dose of 2000 mg/kg.

Results and discussion

Preliminary study:

No real preliminary study, but only one animal was dosed in the beginning (cf. above: Details on study design):
Available information indicated test item is likely to be nontoxic considering to acute toxicity. Therefore, a limit dose of 2000 mg/kg was used as starting dose. One female was dosed. Test item-related mortality was not produced during 24-hours exposure period. The sighting study was finished.

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Mortality:

no mortality

Clinical signs:

other: No important signs of toxicity were observed during the first 4 hours neither in females nor in males or in 14 days observation period.

Gross pathology:

All animals (5 females and 5 males) were necropsied. During necropsy, no macroscopically changes were noticed.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The limit dose of 2000 mg/kg did not cause death, evident symptoms of toxicity or important body weight losses during the 14 days long observation period.
Therefore, classification is not warranted.

Executive summary:

The purpose of the study was to evaluate the potential toxic effect of the test item Cobalt Molybdenum Oxide when applicate as a single dermal dose to Wistar rats. The procedure according to OECD Guideline 402 Acute Dermal Toxicity and OECD Proposal for a New Draft Guideline 434: Acute Dermal Toxicity-Fixed Dose Procedure was used.

A limit dose of 2000 mg/kg was used as starting dose. One female was dosed. Test item-related mortality was not produced during 24 hours. A total of five female rats were dosed with a limit dose of 2000 mg/kg. An additional group of 5 males was tested at the same dose.