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Toxicological information

Genetic toxicity: in vivo

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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
Study period:
1986-12-09 to 1986-12-12
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: - Guideline study - GLP study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1987
Report Date:
1987

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)
Version / remarks:
as at 1983
Deviations:
yes
Remarks:
: in contrast to the OECD guideline from 1997, only 1000 PCE analyzed
Principles of method if other than guideline:
- cells were harvested from bone marrow
GLP compliance:
yes
Type of assay:
micronucleus assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: particulate/powder
Remarks:
migrated information: powder

Test animals

Species:
mouse
Strain:
other: BOR: NMRI, (SPF Han)
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Winkelmann, Versuchstierzucht GmbH & Co. KG., D-4799 Borchen
- Age at study initiation: 6 weeks
- Weight at study initiation: 33 - 39 g (males), 26 - 32 g (females)
- Assigned to test groups randomly: yes, under following basis: computer generated random numbers
- Fasting period before study:
- Housing: 1 per cage (Makrolon cage, type II)
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: 6 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 2 °C
- Humidity (%): 50 ± 15 %
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
- Vehicle(s)/solvent(s) used:peanut oil
- Justification for choice of solvent/vehicle: non stated, but test substance decomposes in water
- Concentration of test material in vehicle: 61.9 mg/mL
- Amount of vehicle: 10 mL/kg/bw
- Lot/batch no. : not reported
- Purity: not reported
- Identity of vehicle: Peanut oil (Oleum arachidis DAB 8, Fa. H. Lamotte, D-2800 Bremen)
Details on exposure:
PREPARATION OF DOSING SOLUTIONS:
- suspension of the test substance in the vehicle was prepared immediately before administration by adding the test substance to the vehicle. The mixture was homogenized using an ultra turrax homogenizer (Janke u. Kunkel, D-7813 Staufen, Germany)

Duration of treatment / exposure:
- single dosage via gavage
Frequency of treatment:
- single dosage via gavage
Post exposure period:
- 24, 48, and 72 h post administration 6 animals of each sex were sacrificed for examination
Doses / concentrations
Remarks:
Doses / Concentrations:
619 mg/kg bw
Basis:
other: via gavage
No. of animals per sex per dose:
18
Control animals:
yes, concurrent vehicle
Positive control(s):
cyclophosphamide
- Justification for choice of positive control(s): none stated
- Route of administration: oral via gavage
- Dose: 51.1 mg/kg bw, dissolved in 0.9% saline solution

Examinations

Tissues and cell types examined:
bone marrow cells from the femurs
Details of tissue and slide preparation:
CRITERIA FOR DOSE SELECTION:
Obvious clinical symptoms of intoxication and deaths were observed at 1000 mg/kg bw in an orientating study

TREATMENT AND SAMPLING TIMES ( in addition to information in specific fields):
single dosage via gavage, sampling at 24, 48, and 72 h post administration (6 animals of each sex)

DETAILS OF SLIDE PREPARATION:
- at least two slides per animals were prepared
- animals were sacrificed by CO2 overdose
- both femurs removed and bone marrow cells flushed into labelled centrifuge tubes with 1.5 ml fetal calf serum (Art. No. 210463, Boehringer Mannheim, D-6800 Mannheim 1)
- centrifugation of tubes: 1000 rpm, 5 min (Labofuge 6000, Heraeus-Christ GmbH, D3360 Osterode am Harz)
- supernatant discarded, bone marrow cells suspended upon a thin layer of serum
- the marrow serum suspension was smeared on a slide and dried over night (slide identification: project no., animal no., species, sex, material, date of preparation)
- two slides were stained using the panoptic stain method (Pappenheim et. al, Das Knochenmark, p. 12, ed. Queisser W., Georg Thieme Verlag, Stuttgart, 1978)

METHOD OF ANALYSIS:
- 1000 PCE were scored for the incidence of micronuclei under the microscope (magnification 1000 x, C. Zeiss, D-7082 Oberkochem, Germany) (one slide used per animal, the second as back up)

OTHER:

- The ration of polychromatic to normochromatic erythrocytes was calculated based on 1000 erythrocytes as a measure of the toxic efficacy of the test material
Evaluation criteria:
- If a test material produced no statistical significant and reproducible positive response at any one of the test points compared to the negative control group, it was considered non mutagenic in this system (significance level: 5%)
Statistics:
- The frequencies of micronuclei of the test group and the positive control group were compared with those of the negative control group at each sampling time.
- A POISSON test was applied. Estimation and test for each treatment group and each sex by means of a VAX 750 computer

Results and discussion

Test resultsopen allclose all
Sex:
male
Genotoxicity:
negative
Toxicity:
yes
Remarks:
two animals died, one at day 1, one at day 3 post administration
Vehicle controls validity:
valid
Negative controls validity:
not applicable
Positive controls validity:
valid
Sex:
female
Genotoxicity:
negative
Toxicity:
yes
Remarks:
two animals died, both on day 2 post administration
Vehicle controls validity:
valid
Negative controls validity:
not applicable
Positive controls validity:
valid

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information): negative
Based on the results of the present mammalian erythrocyte micronucleus test cyanuric chloride can be regarded as non mutagenic under the test conditions.