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Toxicological information

Eye irritation

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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 guidelineopen allclose all
Qualifier:
according to guideline
Guideline:
EU Method B.5 (Acute Toxicity: Eye Irritation / Corrosion)
Qualifier:
according to guideline
Guideline:
OECD Guideline 405 (Acute Eye Irritation / Corrosion)
GLP compliance:
yes

Test material

Constituent 1
Chemical structure
Reference substance name:
Zinc
EC Number:
231-175-3
EC Name:
Zinc
Cas Number:
7440-66-6
Molecular formula:
Zn
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).