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Diss Factsheets

Administrative data

Endpoint:
in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus
Remarks:
Type of genotoxicity: chromosome aberration
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Basic data given: comparable to guidelines/standards

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1986
Report date:
1986

Materials and methods

Test guideline
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)
Deviations:
yes
Remarks:
only 1000 PCE counted
GLP compliance:
no
Type of assay:
micronucleus assay

Test material

Constituent 1
Details on test material:
- Analytical purity: commercial grade
- Lot/batch No.: Op. 10002

Test animals

Species:
hamster, Chinese
Strain:
not specified
Sex:
male/female
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: CIBA-GEIGY Tierfarm, Sisseln
- Age at study initiation: female: 6-10 weeks, male: 4-9 weeks
- Weight at study initiation: female: 22-33 g, male: 27-35 g
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period:

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 - 23
- Humidity (%): 47 -50
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
- Vehicle(s)/solvent(s) used: 0.5% CMC (carboxymethyl cellulose)
Duration of treatment / exposure:
single treatment
Frequency of treatment:
single treatment
Post exposure period:
16, 24, 48 hours
Doses / concentrations
Remarks:
Doses / Concentrations:
5000 mg/kg
Basis:
actual ingested
No. of animals per sex per dose:
8
Control animals:
yes, concurrent vehicle
Positive control(s):
cyclophosphamide
- Route of administration: no data
- Doses / concentrations: 64 mg/kg at 20 mL/kg

Examinations

Tissues and cell types examined:
bone marrow
Details of tissue and slide preparation:
CRITERIA FOR DOSE SELECTION: In this experiment the dose of 5000 mg/kg was determined as the highest applicable in the mutagenicity assay.

DETAILS OF SLIDE PREPARATION: Small drops of the mixture were transferred on the end of a slide, spread out by pulling it behind a polished cover glass and the preparations were air-dried. Three hours later, the slides were stained in undiluted May-Gruenwald solution for 2 min then in May-Gruenwald solution/water 1/1 for 2 min and then in Giemsa's, 40% for 20 min. After being rinsed in methanol 55% for 5-8 sec and washed off twice in water,
they were left immersed in water for approx. 2 min. After rinsing with distilled water and air-drying, the slides were cleared in Xylene and mounted in Eukitt.

METHOD OF ANALYSIS: microscopically, 1000 polychromatic erythrocytes each were scored for the incidence of micronuclei per animal. The ratio of polychromatic to normochromatic erythrocytes was determined for each animal by counting a total of 1000 erythrocytes.
Statistics:
The significance ot difference was assessed by chi-square -test.

Results and discussion

Test results
Sex:
male/female
Genotoxicity:
negative
Toxicity:
no effects
Vehicle controls validity:
valid
Negative controls validity:
not examined
Positive controls validity:
valid

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information): negative
It is concluded that under the conditions of this experiment, no evidence of mutagenic effects was obtained in Chinese hamsters treated with the test substance.