Cobalt di(acetate)

Eye irritation

Administrative data

Endpoint:

eye irritation, other

Remarks:

in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2012-10-09 to 2012-11-12

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Version / remarks:

2002-04-24

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

date of inspection: 2012-07-10

Test material

Test material information

Constituent 1

Reference substance name:

Cobalt di(acetate)

EC Number:

200-755-8

EC Name:

Cobalt di(acetate)

Cas Number:

71-48-7

Molecular formula:

C2H4O2.1/2Co

IUPAC Name:

cobalt(2+) diacetate

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

- Name of test material (as cited in study report): COBALT ACETATE
- Physical state: pink powder
- Storage condition of test material: room temperature in the dark

Test animals / tissue source

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS - New Zealand White (Hsdlf:NZW) strain rabbits
- Source: Harlan Laboratories UK Ltd., Leicestershire, UK
- Age at study initiation: twelve to twenty weeks old
- Weight at study initiation: 2.42 or 2.66 kg
- Housing: the animals were individually housed in suspended cages.
- Diet (ad libitum): 2930C Teklad Global Certified Rabbit diet supplied by Harlan Laboratories UK Ltd., Oxon, UK)
- Water (ad libitum): mains drinking water
- Acclimation period: at least five days

The animals were provided with environmental enrichment items which were considered not to contain any contaminant of a level that might have affected the purpose or integrity of the study.

ENVIRONMENTAL CONDITIONS
- Temperature: 17 to 23°C
- Relative humidity: 30 to 70%
- Air exchange: at least fifteen changes per hour
- Photoperiod (hrs dark / hrs light): 12/12

Test system

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): a volume of 0.1 ml of the test item, which was found to weigh approximately 77 mg (as measured by gently compacting the required volume into an adapted syringe) was placed into the conjunctival sac of the right eye, formed by gently pulling the lower lid away from the eyeball. The upper and lower eyelids were held together for about one second immediately after treatment, to prevent loss of the test item, and then released. The left eye remained untreated and was used for control purposes.

Duration of treatment / exposure:

not applicable

Observation period (in vivo):

approximately 1 hour and 24, 48 and 72 hours following treatment as well as on days 7 and 14

Number of animals or in vitro replicates:

2 male rabbits

Details on study design:

Immediately before the start of the test, both eyes of the provisionally selected test rabbits were examined for evidence of ocular irritation or defect with the aid of a light source from a standard ophthalmoscope. Only animals free of ocular damage were used.

INITIAL AND CONFIRMATORY TEST
Initially, a single rabbit was treated. Immediately after administration of the test item, an assessment of the initial pain reaction was made according to the six point scale (please refer to table 2 in the field "Any other information on materials and methods incl. tables" below).
After consideration of the ocular responses produced in the first treated animal, a second animal was treated.

SCORING SYSTEM: according to the Draize scale
Any other ocular effects were also noted.
Any clinical signs of toxicity, if present, were also recorded.
Individual bodyweights were recorded on Day 0 (the day of dosing) and at the end of the observation period.
If evidence of irreversible ocular damage is noted, the test item will be classified as corrosive to the eye.

TOOL USED TO ASSESS SCORE: examination of the eye was facilitated by the use of the light source from a standard ophthalmoscope.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

cornea opacity score

Basis:

mean

Remarks:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

4

Remarks on result:

other: Initial pain reaction: slight initial pain; Slight to moderate discharge was observed at the 1, 24 and 48 hour observations.

Results 2

Irritation parameter:

iris score

Basis:

mean

Remarks:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

2

Results 3

Irritation parameter:

conjunctivae score

Basis:

mean

Remarks:

animal #1

Time point:

24/48/72 h

Score:

2

Max. score:

3

Reversibility:

fully reversible within: 14 days

Remarks on result:

other: Moderate conjunctivae redness was observed at the 1 hour observation.

Results 4

Irritation parameter:

chemosis score

Basis:

mean

Remarks:

animal #1

Time point:

24/48/72 h

Score:

1.67

Max. score:

4

Reversibility:

fully reversible within: 14 days

Remarks on result:

other: Moderate chemosis was observed at the 1 hour observation.

Results 5

Irritation parameter:

cornea opacity score

Basis:

mean

Remarks:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

4

Remarks on result:

other: Initial pain reaction: moderate initial pain; Slight to moderate discharge was observed at the 1, 24, 48 and 72 hour observation.

Results 6

Irritation parameter:

iris score

Basis:

mean

Remarks:

animal #2

Time point:

24/48/72 h

Score:

0.33

Max. score:

2

Reversibility:

fully reversible within: 48 hours

Results 7

Irritation parameter:

conjunctivae score

Basis:

mean

Remarks:

animal #2

Time point:

24/48/72 h

Score:

2

Max. score:

3

Reversibility:

fully reversible within: 14 days

Remarks on result:

other: Small areas of petechial haemorrhage of the nictitating membrane was observed at the 24, 48 adn 72 hour observations. Moderate conjunctivae redness was observed at the 1 hour observation.

Results 8

Irritation parameter:

chemosis score

Basis:

mean

Remarks:

animal #2

Time point:

24/48/72 h

Score:

1.33

Max. score:

4

Reversibility:

fully reversible within: 14 days

Remarks on result:

other: Moderate chemosis was observed at the 1 hour observation.

Irritant / corrosive response data:

No corneal effects were noted during the study.
Iridial inflammation was noted in one treated eye at the 24-hour observation.
Moderate conjunctival irritation was noted in both treated eyes one hour after treatment and at the 24 and 48-Hour observations. Moderate conjunctival irritation was noted in one treated eye with minimal conjunctival irritation noted in the other treated eye at the 72-Hour observation. Minimal conjunctival irritation was noted in both treated eyes at the 7-Day observation.
Small areas of petechial haemorrhage on the nictitating membrane were noted in one treated eye at the 24, 48 and 72-hour observations.
Both treated eyes appeared normal at the 14-Day observation.

Other effects:

- Bodyweight: both animals showed expected gain in bodyweight during the study.

Applicant's summary and conclusion

Interpretation of results:

Category 2 (irritating to eyes) based on GHS criteria

Conclusions:

The test material is irritating to the eyes.
According to the EC Regulation No. 1272/2008 and subsequent regulations, the substance is classified as Category 2.