Cobalt dinitrate

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation / corrosion, other

Remarks:

in vivo study

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2012-03-27 to 2012-04-03

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Version / remarks:

2002-04-24

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Cobalt dinitrate

EC Number:

233-402-1

EC Name:

Cobalt dinitrate

Cas Number:

10141-05-6

Molecular formula:

Co.2NO3

IUPAC Name:

cobalt(2+) dinitrate

Test material form:

solid: crystalline

Details on test material:

- Name of test material (as cited in study report): cobalt dinitrate
- Physical state: brown crystals
- Stability of test item: stable under storage conditions
- Storage condition of test material: closed container, away from light, room temperature

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Kuiper Rabbitry, Gary, Indiana
- Age at study initiation: approximately ten to twelve weeks old
- Weight at study initiation: 2.79 to 2.91 kg
- Housing: individually housed in stainless steel cages
- Diet (ad libitum): Purina Laboratory Rabbit Chow
- Water (ad libitum)
- Acclimation period: at least five days

The rabbits were maintained according to the recommendations contained in the National Academy Press 1996: "Guide for the Care and Use of Laboratory Animals".

ENVIRONMENTAL CONDITIONS
- Temperature: 20 ± 3° C
- Humidity: 30-70%
- Photoperiod (hrs dark / hrs light): 12/12

Test system

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

water

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 g. aliquot of the test material was slightly moistened with the vehicle

Duration of treatment / exposure:

Initial animal: 3 minutes, 1 hour and 4 hours
Confirmatory animals: 4 hours

Observation period:

30 minutes, 24, 48, 72 and 168 hours after removal of the test substance

Number of animals:

3 male rabbits

Details on study design:

INITIAL AND CONFIRMATORY TEST
One animal was screened by applying the test substance for a 3 minute and 1 hour topical exposure. No irritation was observed in either exposure; therefore the four hour exposure was conducted.

TEST SITE
- Area of exposure/Type of wrap if used: the day before study initiation, electric clippers were used to remove the hair from the left side of the trunk, from the midline of the back to the abdomen. The following day an aliquot of the test material was slightly moistened with the vehicle and applied to an area approximately 6 square centimeters on the side of the test animal. The application site is located approximately 5-7 centimeters down from the backbone. The test substance was then covered with a 2.5 cm² - 2 layer gauze patch held in place with non-irritating Kendall Curity Standard Porous Tape and the patch was then covered with a occlusive plastic overwrap secured in place with Kendall Curity Standard Porous Tape for the duration of the exposure period.

REMOVAL OF TEST SUBSTANCE
- Time after start of exposure: at the end of the 4 hour contact period

SCORING SYSTEM: according to the Draize scale
Other adverse changes at the skin will be reocrded if present

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

mean

Remarks:

animal #1

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible within: 7 days

Results 2

Irritation parameter:

edema score

Basis:

mean

Remarks:

animal #1

Time point:

24/48/72 h

Score:

0.67

Max. score:

4

Reversibility:

fully reversible within: 72 hours

Results 3

Irritation parameter:

erythema score

Basis:

mean

Remarks:

animal #2

Time point:

24/48/72 h

Score:

1.67

Max. score:

4

Reversibility:

fully reversible within: 7 days

Results 4

Irritation parameter:

edema score

Basis:

mean

Remarks:

animal #2

Time point:

24/48/72 h

Score:

0.33

Max. score:

4

Reversibility:

fully reversible within: 48 hours

Results 5

Irritation parameter:

erythema score

Basis:

mean

Remarks:

animal #3

Time point:

24/48/72 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 7 days

Results 6

Irritation parameter:

edema score

Basis:

mean

Remarks:

animal #3

Time point:

24/48/72 h

Score:

0.33

Max. score:

4

Reversibility:

fully reversible within: 48 hours

Irritant / corrosive response data:

There were mild irritation reactions in all three the test subjects which cleared by the 168 hour observation.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The test substance is not irritating to the skin.
According to the EC-Regulation 1272/2008 and subsequent regulations, the test item is not classified as skin irritant.