Registration Dossier

Administrative data

Description of key information

key studies demonstrate a lack of irritation/corrosion potential

Key value for chemical safety assessment

Skin irritation / corrosion

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not irritating)

Eye irritation

Link to relevant study records
Reference
Endpoint:
eye irritation: in vivo
Type of information:
read-across based on grouping of substances (category approach)
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Justification for type of information:
See appendix on read across in iuclid section 13
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)
Principles of method if other than guideline:
none
GLP compliance:
yes
Species:
rabbit
Strain:
New Zealand White
Details on test animals or tissues and environmental conditions:
see reference
Vehicle:
unchanged (no vehicle)
Controls:
yes, concurrent no treatment
Amount / concentration applied:
64 mg ZnO (volume of 0.1 mL)
Duration of treatment / exposure:
24 hours
Observation period (in vivo):
1, 24, 48 and 72 hours after exposure
Number of animals or in vitro replicates:
3 males
Details on study design:
see reference
Irritation parameter:
conjunctivae score
Basis:
mean
Time point:
24/48/72 h
Score:
>= 0.7 - <= 1
Max. score:
3
Reversibility:
fully reversible
Remarks:
in 72h
Remarks on result:
no indication of irritation
Irritation parameter:
cornea opacity score
Basis:
mean
Time point:
24/48/72 h
Score:
0
Max. score:
4
Remarks on result:
no indication of irritation
Irritation parameter:
iris score
Basis:
mean
Time point:
24/48/72 h
Score:
0
Max. score:
2
Remarks on result:
no indication of irritation
Irritation parameter:
chemosis score
Basis:
mean
Time point:
24/48/72 h
Score:
0
Max. score:
4
Remarks on result:
no indication of irritation
Irritant / corrosive response data:
No symptoms of systemic toxicity were observed and no mortality occurred. Slight iridial irritation (grade 1) was observed in one animal, at 1 hour only. Slight irritation of the conjuctivae (grade 1-2) was seen as redness (mean scores over 24-72 hours 0.7, 1 and 1), which had completely resolved at 72 hours in all animals. Chemosis (grade 2) and discharge (grade 1) were also observed in all animals, but at 1 hour only. No corneal opacity or epithelial damage was observed in any of the animals
Other effects:
none
Interpretation of results:
not irritating
Remarks:
Migrated information Criteria used for interpretation of results: EU
Conclusions:
ZnO not irritating in an vivo rabbit study.
Executive summary:

In an eye irritation/corrosion well-performed study according to Directive 92/69/EEC B.5 and OECD guideline 405, three male New Zealand White rabbits were treated by instillation of approximately 64 mg of zinc oxide (a volume of about 0.1 ml) 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. Slight iridial irritation (grade 1) was observed in one animal, at 1 hour only. Slight irritation of the conjuctivae (grade 1-2) was seen as redness (mean scores over 24-72 hours 0.7, 1 and 1), which had completely resolved at 72 hours in all animals. Chemosis (grade 2) and discharge (grade 1) were also observed in all animals, but at 1 hour only. No corneal opacity or epithelial damage was observed in any of the animals.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not irritating)

Additional information

Based on the available information it appears that he slightly soluble zinc oxide and insoluble zinc sulphide are not skin irritants and therefore slightly soluble zinc hydroxide, zinc phosphate, zinc carbonate and zinc metal are also expected to be not irritating to skin. Zinc oxide, zinc phosphate, zinc metal and zinc sulphide are not eye irritants and therefore zinc carbonate and zinc hydroxide are also expected to be not irritating to eyes. None of the slightly soluble or insoluble zinc compounds appear to cause respiratory tract irritation.

The slightly soluble and insoluble zinc compounds (zinc oxide, zinc hydroxide, zinc phosphate, zinc carbonate, zinc metal and zinc sulphide) are not corrosive based on the available irritation data.

Justification for classification or non-classification

The slightly soluble and insoluble zinc compounds ( zinc oxide, zinc hydroxide, zinc phosphate, zinc carbonate, zinc metal and zinc sulphide)

are not irritating or corrosive based on the available irritation data and therefore no classification is required according to EC criteria either for irritation or corrosion.