Zinc sulphide

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

migrated information: read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Guideline study used as a key study in EU risk assessment of zinc metal

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1999

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EU Method B.5 (Acute Toxicity: Eye Irritation / Corrosion)

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Zinc

EC Number:

231-175-3

EC Name:

Zinc

Cas Number:

7440-66-6

IUPAC Name:

zinc

Details on test material:

metallic zinc dust (median particle diameter 4 micrometer

Test animals / tissue source

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

none

Test system

Vehicle:

not specified

Controls:

yes, concurrent no treatment

Amount / concentration applied:

100 mg of test substance

Duration of treatment / exposure:

24 hours

Observation period (in vivo):

1, 24, 48 and 72 hours

Number of animals or in vitro replicates:

3

Details on study design:

three male New Zealand White rabbits were treated by instillation of approximately 100 mg of the substance into the conjuctival sac of one eye. The other eye remained untreated and served as control. After 24 hours, both eyes of two animals were rinsed with water. The eyes were examined at 1, 24, 48 and 72 hours after instillation.

Results and discussion

In vivo

Results

Irritation parameter:

conjunctivae score

Basis:

mean

Time point:

other: 24-72 h

Score:

>= 0.7 - < 1

Reversibility:

fully reversible

Remarks:

in 72 h

Irritant / corrosive response data:

Slight irritation of the conjuctivae, which was seen as redness (grade 1-2; mean scores over 24-72 hours 1, 1 and 0.7) that had completely resolved at 72 hours in all animals. Chemosis (grade 1-2) was also observed in all animals at 1 hour only, while discharge (grade 1) was observed at 1 (two animals) and 24 hours (one animal).

Other effects:

no symptoms of systemic toxicity and no mortality occured. No iridial irritation and no corneal opacity or epithelial damage was observed in any of the animals.

Any other information on results incl. tables

none

Applicant's summary and conclusion

Interpretation of results:

slightly irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Based on the eye irritation data, zinc dust is not irritating/corrosive to the eyes. Hence, according to EU criteria, metallic zinc does not have to be classified/labelled for irritating properties.

Executive summary:

A well-performed eye irritation/corrosion studie, conducted according to Directive 92/69/EEC B.5 and OECD guideline 405, was carried out with metallic zinc dust (median particle diameter 4mm).

Three male New Zealand White rabbits were treated by instillation of approximately 100 mg of the substance into the conjuctival sac of one eye. The other eye remained untreated and served as control. After 24 hours, both eyes of two animals were rinsed with water. The eyes were examined at 1, 24, 48 and 72 hours after instillation.

No symptoms of systemic toxicity were observed and no mortality occurred. Also, no iridial irritation and no corneal opacity or epithelial damage was observed in any of the animals. Zinc dust caused slight irritation of the conjuctivae, which was seen as redness (grade 1-2; mean scores over 24-72 hours 1, 1 and 0.7) that had completely resolved at 72 hours in all animals. Chemosis (grade 1-2) was also observed in all animals at 1 hour only, while discharge (grade 1) was observed at 1 (two animals) and 24 hours (one animal).