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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:
1992-09-04 to 1992-09-12
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: This study is classified as reliable with restriction because although it is an acceptable and well documented study report the GLP compliance was unknown.
Justification for type of information:
A discussion and report on the read across strategy is given as an attachment in Section 13.
Cross-reference
Reason / purpose:
read-across: supporting information

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1993
Report Date:
1993

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)
GLP compliance:
not specified
Type of assay:
micronucleus assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): Heptenes (CAS 68526-53-4)
- Physical state: colourless liquid
Stability, identity, strength, purity, and composition are the responsibility of the sponsor and not provided in the study report.

Test animals

Species:
mouse
Strain:
B6C3F1
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Charles River Raleigh
- Age at study initiation: approximately 7 to 9 weeks
- Weight at study initiation: Between 19 to 28 grams
- Assigned to test groups randomly: Chosen by body weight by computer generated sorting system.
- Fasting period before study: not reported
- Housing: Single after approximately one week in suspended stainless steel
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: 13 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 to 24 degrees Celsius
- Humidity (%): 40 to 70% humidity
- Air changes (per hr): not reported
- Photoperiod (hrs dark / hrs light): 12 hours dark/ 12 hours light.


IN-LIFE DATES: From: 1992-09-01 To: 1992-11-04

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
- Vehicle(s)/solvent(s) used: corn oil
- Justification for choice of solvent/vehicle: not reported
- Concentration of test material in vehicle: equal amounts of test material and vehicle.
- Amount of vehicle (if gavage or dermal): Same amount as test material (1.25, 2.05, or 5.0 g/kg/bw
- Purity: 100%
Details on exposure:
PREPARATION OF DOSING SOLUTIONS: The test material was weighed on the day of dosing and mixed with the corn oil to provide stock solution such that each individual animal dose volume did not exceed 1.0 ml/100 grams bw.


DIET PREPARATION - test material administered by oral gavage
- Rate of preparation of diet (frequency): not applicable
- Mixing appropriate amounts with (Type of food): not applicable
- Storage temperature of food: not applicable
Duration of treatment / exposure:
Animals from the appropriate groups were sacrificed approximately 24, 48, and 72 hours after dose administration. Animals dosed with cyclophosphamide were sacrificed at 24 hours only.
Frequency of treatment:
Test material was administered by oral gavage as a single dose
Post exposure period:
Not applicable.
Doses / concentrationsopen allclose all
Remarks:
Doses / Concentrations:
1.25 g/kg bw
Basis:
other: Corn oil was dosed with the test material at the same volume as the test material.
Remarks:
Doses / Concentrations:
2.5 g/kg bw
Basis:
other: Corn oil was dosed with the test material at the same volume as the test material.
Remarks:
Doses / Concentrations:
5.0 g/kg bw
Basis:
other: Corn oil was dosed with the test material at the same volume as the test material.
No. of animals per sex per dose:
15 animals per sex per dose
Control animals:
not specified
Positive control(s):
cyclophosphamide
- Justification for choice of positive control(s): not reported
- Route of administration: oral gavage
- Doses / concentrations: equal volume to the test material dose volume

Examinations

Tissues and cell types examined:
Bone marrow from femurs.
Details of tissue and slide preparation:
CRITERIA FOR DOSE SELECTION: Not reported

TREATMENT AND SAMPLING TIMES ( in addition to information in specific fields): No additional data reported


DETAILS OF SLIDE PREPARATION:
Two slides were prepared per animals, labelled with animal identification number and study number. Prior to microscopic evaluation, slides were trained using acridine orange. Polychromatic erythrocytes stain fluorescent red/orange, normochromatic erythrocytes are unstained or stain a dull green, and micronuclei stain fluorescent bright yellow.

METHOD OF ANALYSIS:


OTHER:
Evaluation criteria:
Criteria for scoring micronuclei are circular appearance and diameter between 1/20 and 1/5 of the cell's diameter. 1000 polychromatic erythrocytes (PCE) from each animal were examined for micronuclei, and the ratio of PCE's to normochromatic erythrocytes (NCE) was determined for each animal by counting 1000 erythrocytes.
Statistics:
Calculation of means and standard deviations of the micronuclei data and a test of equality of group means by a standard one way analysis of variance at each time period. When the ANOVA was significant, Duncan's Multiple Range Test was used to compare carrier control to dosed group means. A standard regression analysis was performed to test for a dose response.

Results and discussion

Test results
Sex:
male/female
Genotoxicity:
negative
Toxicity:
no effects
Vehicle controls valid:
yes
Negative controls valid:
yes
Positive controls valid:
yes
Additional information on results:
None reported

Applicant's summary and conclusion

Conclusions:
negative

The test material did not induce statistically significant decrease in the mean percent of polychromatic erythrocytes which is a measure of bone marrow toxicity. Thus the test material was not toxic to mouse bone marrow under the conditions of the test. This test material did not induce a statistically significant increase in the mean number of micronucleated polychromatic erythrocytes. Both positive and negative controls for the assay responded in an appropriate manner. The test material did not produce clastogenic abnormalities in the bone marrow cells of B6C3F1 mice at doses up to and including 5.0 g/kg under the conditions of the assay.
Executive summary:

In a B6C3F1 bone marrow micronucleus assay 65 male and 65 female mice were treated via oral gavage with heptenes at doses of 1.25, 2.5, and 5.0 g/kg bw. Bone marrow cells were harvested at 24, 48, and 72 hours post treatment. The vehicle was corn oil via oral gavage.

The test material did not induce statistically significant decrease in the mean percent of polychromatic erythrocytes which is a measure of bnbone marrow toxicity. Thus the test material was not toxic to mouse bone marrow under the conditions of the test. This test material did not induce a statistically significant increase in the mean number of micronucleated polychromatic erythrocytes. both positive and negative controls for the assay responded in an appropriate manner. The test material did not produce clastogenic abnormalities in the bone marrow cells of B6C3F1 mice at dose up to and including 5.0 g/kg under the conditions of the assay.

This study received a Klimisch score of two and is classified as reliable with restriction because although it is an acceptable and well documented study report it, GLP compliance was unknown.