Registration Dossier

Administrative data

Endpoint:
eye irritation: in vivo
Type of information:
experimental study
Adequacy of study:
key study
Study period:
Not reported
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Used in risk assessment report for ZnSO4, acceptable for assessment
Justification for data waiving:
other:
Cross-referenceopen allclose all
Reason / purpose:
reference to same study
Reason / purpose:
reference to other study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1999

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 405 (Acute Eye Irritation / Corrosion)
Deviations:
not specified
Qualifier:
according to
Guideline:
EU Method B.5 (Acute Toxicity: Eye Irritation / Corrosion)
Deviations:
not specified
Principles of method if other than guideline:
Not applicable
GLP compliance:
not specified

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): zinc sulphate (ZnSO4.7H2O)

Test animals / tissue source

Species:
rabbit
Strain:
New Zealand White
Details on test animals or tissues and environmental conditions:
No information

Test system

Vehicle:
unchanged (no vehicle)
Controls:
yes, concurrent no treatment
Amount / concentration applied:
Approximately 98.1 mg of the test material
Duration of treatment / exposure:
Single instillation, no eye wash
Observation period (in vivo):
At 1, 24, 48 and 72 hours, 7, 14 and 21 days after exposure.
Number of animals or in vitro replicates:
Three male animals
Details on study design:
No further details

Results and discussion

In vivo

Resultsopen allclose all
Irritation parameter:
conjunctivae score
Remarks:
redness
Basis:
mean
Time point:
other: 24 h
Score:
ca. 2
Max. score:
3
Reversibility:
not specified
Irritation parameter:
conjunctivae score
Remarks:
redness
Basis:
mean
Time point:
other: 48 h
Score:
2.7
Max. score:
3
Reversibility:
not specified
Irritation parameter:
conjunctivae score
Remarks:
redness
Basis:
mean
Time point:
other: 72 h
Score:
ca. 2.7
Max. score:
3
Reversibility:
not specified
Irritation parameter:
chemosis score
Basis:
mean
Time point:
other: 24 h
Score:
ca. 2
Max. score:
4
Reversibility:
not specified
Irritation parameter:
chemosis score
Basis:
mean
Time point:
other: 48 h
Score:
ca. 2.7
Max. score:
4
Reversibility:
not specified
Irritation parameter:
chemosis score
Basis:
mean
Time point:
other: 72 h
Score:
ca. 3.7
Max. score:
4
Reversibility:
not specified
Irritant / corrosive response data:
Corneal injury was seen as slight dulling of the normal lustre (opacity grade 0) and/or epithelial damage (10% of the corneal area) in two animals. This injury had resolved within 24 hours in one animal and within 72 hours in the other animal.
Irritation of the conjuctivae was seen as redness (mean scores over 24-72 hours 2, 2.7 and 2.7), chemosis (mean scores 2, 2.7 and 3.7) and discharge.
Yellow/white spots were observed in the tissue of the lower eyelid, nictitating membrane and/or sclera in all animals from day 7 until termination. These spots were described as signs of necrosis and consisted of encapsulated material of unknown origin which caused protrusions at termination of the study.
Other effects:
Reduced elasticity of the eyelids was noted in one animal, 72 hours and 7 days after instillation.

Any other information on results incl. tables

None       

Applicant's summary and conclusion

Interpretation of results:
highly irritating
Remarks:
Migrated information Criteria used for interpretation of results: EU
Conclusions:
Based on the degree and persistence of the corneal injury, zinc sulphate is considered to cause severe ocular irritation
Executive summary:

In a well-performed eye irritation/corrosion study, conducted according to Directive 92/69/EEC B.5 and OECD guideline 405, three male New Zealand White rabbits were treated by instillation of approximately 98.1 mg of zinc sulphate (ZnSO4.7H2O) into the conjuctival sac of one eye. The other eye remained untreated and served as control. The eyes (unrinsed) were examined at 1, 24, 48 and 72 hours and 7, 14 and 21 days after instillation.

No symptoms of systemic toxicity were observed and no mortality occurred.

Corneal injury was seen as slight dulling of the normal lustre (opacity grade 0) and/or epithelial damage (10% of the corneal area) in two animals. This injury had resolved within 24 hours in one animal and within 72 hours in the other animal.

Irritation of the conjuctivae was seen as redness (mean scores over 24-72 hours 2, 2.7 and 2.7), chemosis (mean scores 2, 2.7 and 3.7) and discharge.

Yellow/white spots were observed in the tissue of the lower eyelid, nictitating membrane and/or sclera in all animals from day 7 until termination. These spots were described as signs of necrosis and consisted of encapsulated material of unknown origin which caused protrusions at termination of the study. Reduced elasticity of the eyelids was noted in one animal, 72 hours and 7 days after instillation.

Based on the degree and persistence of the corneal injury, zinc sulphate is considered to cause severe ocular irritation.