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Toxicological information

Acute Toxicity: dermal

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Administrative data

Endpoint:
acute toxicity: dermal
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: The study is conducted accordign to the OECD Guideline in compliance with GLP.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2010
Report Date:
2010

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 402 (Acute Dermal Toxicity)
Deviations:
no
GLP compliance:
yes (incl. certificate)
Test type:
standard acute method
Limit test:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: nanoform
Details on test material:
- Name of test material (as cited in study report): Z-COTE HP1
- Molecular weight (if other than submission substance): 81.38 g/mol
- Physical state: Solid
- Composition of test material, percentage of components: Z-COTE HP1 (98%), coated with triethoxycaprylylsilane (CAS # 2943-75-1; 2%)
- Lot/batch No.: NPL Ref#: ZB250#65
- Expiration date of the lot/batch: June 2014
- Storage condition of test material: Room temperature, dry, exclusion of light

Test animals

Species:
rat
Strain:
Wistar
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Charles River, Sulzefeld, Germany
- Age at study initiation: 10 - 11 weeks
- Weight at study initiation: males (mean): 308.92 g, females (mean): 193.28 g
- Housing: 2 rats of same sex per cage, wooden absorbing bedding
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: 4 weeks

ENVIRONMENTAL CONDITIONS
- Temperature: 22 +/- 2°C
- Humidity: 55 +/- 15%
- Air changes (per hr): fully airconditioning
- Photoperiod (hrs dark / hrs light): 12 h / 12 h

Administration / exposure

Type of coverage:
semiocclusive
Vehicle:
corn oil
Details on dermal exposure:
TEST SITE
- Area of exposure: back

REMOVAL OF TEST SUBSTANCE
- Washing (if done): water
- Time after start of exposure: 24 h

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 2000mg/kg bw
- Concentration (if solution): 0.5mg test item in 400µl corn oil
- Constant volume or concentration used: no
- For solids, paste formed: yes
Duration of exposure:
24 h
Doses:
2000 mg/kg bw
No. of animals per sex per dose:
5/sex
Control animals:
other: untreated skin of same animal
Details on study design:
- Duration of observation period following administration: 14 d
- Frequency of observations and weighing: Twice a day, once on weekends
- Necropsy of survivors performed: Yes
- Other examinations performed: Clinical signs, body weight, gross pathology
Statistics:
Means and standard deviation were calculated using standard statistical tests.

Results and discussion

Effect levels
Sex:
male/female
Dose descriptor:
LD50
Effect level:
> 2 000 mg/kg bw
Based on:
test mat.
Remarks on result:
other: No mortality occured
Mortality:
Not observed
Clinical signs:
Slight signs of general discomfort as often seen in dermal toxicity studies, the general health status was good throughout the study
Body weight:
Treatment related effects were not observed
Gross pathology:
No abnormalties detected

Applicant's summary and conclusion

Interpretation of results:
not classified
Remarks:
Migrated information Criteria used for interpretation of results: EU
Conclusions:
Under the test conditions, the LD50 of nanoscaled ZnO is estimated to be > 2000mg/kg bw.
Executive summary:

The study was conducted to determine the acute dermal toxicity of nanoscaled ZnO according to the OECD Guideline 402 in compliance with GLP.

2000 mg/kg bw of the test substance were semiocclusively administered for 24 h as pasty formulation in corn oil to the shaved and defaffed back of 5 female and 5 male rats. After the end of the exposure period, the test substance paste was recovered as effectively as possible using water and the animals were observed for 14 d. During the present study no mortality occurred and there were no indications of systemic toxicity, no effects regarding the body weight and neither clinical signs nor pathological findings observed.

The LD50 of the test substance is therefore estimated to be > 2000 mg/kg bw.