Registration Dossier

Administrative data

Description of key information

Skin irritation:
An in vivo study realized according to the OECD Guideline 404 shows that the test substance is not irritating to the skin of rabbits (The British Industrial Biological Research Association, 1986). This study was scored Klimisch 2.
Eye irritation:
2 reliable studies are used in a 'weight-of-evidence' approach: one in vitro study (scored Klimisch 2) with zirconium basic carbonate (Harlan Laboratories, 2010) and one read-across in vivo study (scored Klimisch 2) with yttrium zirconium dioxide (Chemical Evaluation and Research Institute, 2000).
Harlan Laboratories Ltd (2010) studied the eye irritation potential of the test material using the SkinEthic Reconstituted Human Corneal model (HCE, SkinEthic Laboratories, Nice, France) after a treatment period of 10 minutes. The test is based on the hypothesis that irritant chemicals are able to penetrate the stratum corneum of the SkinEthic RHC model and are sufficiently cytotoxic to cause cell death in the underlying cell layers. According to the protocol followed the test material was considered to be a non-irritant.
Based on the test results on New Zealand White rabbit according to OECD Guideline 405, the read-across substance yttrium zirconium dioxide did not have to be classified for eye irritation according to the rules of the DSD and CLP (Chemical Evaluation and Research Institute, 2000). This study is added to the weight of evidence approach as in vivo testing is assumed to be more reliable than in vitro testing.
The read-across justification is included in the Section 13 of IUCLID.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records
Reference
Endpoint:
skin irritation: in vivo
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1986-03-04 to 1986-07-17
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Remarks:
Well documented, scientifically sound GLP study that was based on the OECD Guideline 404 "Acute Dermal Irritation/Corrosion". The substance was used as a reference substance and was also tested on the same animals a week following testing of other substances in the study.
Qualifier:
according to guideline
Guideline:
OECD Guideline 404 (Acute Dermal Irritation / Corrosion)
Deviations:
yes
Remarks:
Substance was tested on the same animals a week following testing of the other substances in the study.
GLP compliance:
yes
Species:
rabbit
Strain:
New Zealand White
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: Regal Rabbits, Great Bookham, Surrey
- Housing: individually in metal grid-floored cages
- Diet: ad libitum, Grain Harvester's special rabbit diet 679
- Water: ad libitum tap water
- Acclimation period: 14 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18-23
- Humidity (%): 43-73
Type of coverage:
occlusive
Preparation of test site:
shaved
Vehicle:
water
Controls:
not required
Amount / concentration applied:
TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 g
Duration of treatment / exposure:
4 hours
Observation period:
24, 48 and 72 hours
Number of animals:
4 male animals
Details on study design:
TEST SITE
- Area of exposure: dorsal
- Type of wrap if used: 2.5 cm square patches were applied to the skin on 6 cm square patches of polythene were held in place by adhesive tape and elastic net bandages.


REMOVAL OF TEST SUBSTANCE
- Washing (if done): tap water
- Time after start of exposure: 4 hours


SCORING SYSTEM: Draize (1959), Indices of irritation were calculated for each animal by totalling the scores for oedema and erythema for each animal and dividing by two.
Irritation parameter:
overall irritation score
Basis:
mean
Time point:
other: 24 hours
Score:
ca. 0
Max. score:
8
Irritation parameter:
overall irritation score
Basis:
mean
Time point:
other: 48 hours
Score:
ca. 0
Max. score:
8
Irritation parameter:
overall irritation score
Basis:
mean
Time point:
other: 72 hours
Score:
ca. 0
Max. score:
8
Irritant / corrosive response data:
No reaction to the test substances was reported in any of the test animals.
Interpretation of results:
not irritating
Remarks:
Migrated information Criteria used for interpretation of results: EU
Conclusions:
Under the conditions of the test the test substance was determined not to be irritating to the skin of rabbits.
Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not irritating)

Eye irritation

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

Respiratory irritation

Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

Skin irritation / corrosion:

One reliable study (Klimisch 2) has been identified (BIBRA, 1986). This GLP study was performed according to the OECD 404 guideline with minor deviations and four animals were used.

The substance was determined not to be irritating to New Zealand White rabbit shaved skin after 4 hours of exposure using a occlusive dressing. This study was considered as the key study.

Eye irritation:

A reliable study with zirconium basic carbonate was performed (Harlan Laboratories Ltd, 2010) in vitro in SkinEthic HCE tissues. The purpose of this study was to determine the eye irritation potential of the test material using the SkinEthic Reconstituted Human Corneal model (HCE, SkinEthic Laboratories, Nice, France) after a treatment period of 10 minutes. The test is based on the hypothesis that irritant chemicals are able to penetrate the stratum corneum of the SkinEthic RHC model and are sufficiently cytotoxic to cause cell death in the underlying cell layers. According to the protocol followed the test material was considered to be a non-irritant.

In addition, an in vivo study was performed in New Zealand White rabbits with the read-across substance yttrium zirconium oxide (Chemical Evaluation and Research Institute, 2000). The test substance was determined to be slightly irritating based on the AFNOR criteria. Observed effects were fully reversible within 72 hours. It does however not need to be classified for eye irritation according to the rules in the DSD and CLP. In the case of the zirconium basic carbonate, read across is proposed from yttrium zirconium dioxide in vivo eye testing as both are insoluble and not skin irritant (in vitro). This study is added to the weight of evidence approach for eye irritation as in vivo testing is assumed to be more reliable than in vitro testing.

The read across justification is included in Section 13 of IUCLID.


Justification for selection of skin irritation / corrosion endpoint:
Only one study available

Justification for selection of eye irritation endpoint:
No test is selected as the endpoint is covered by 'Weight-of-evidence' approach.

Justification for classification or non-classification

Based on the available data and according to DSD/CLP criteria, zirconium basic carbonate should not be classified for skin irritation / corrosion or for eye irritation / corrosion.