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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
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Study well described, and meets generally the strandard guidelines.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1994

Materials and methods

Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
Study done according to NTP standard protocols
GLP compliance:
not specified
Type of assay:
micronucleus assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
no data

Test animals

Species:
mouse
Strain:
B6C3F1
Sex:
male
Details on test animals and environmental conditions:
No more information on animals. No data on environmental conditions.

Administration / exposure

Route of administration:
intraperitoneal
Vehicle:
- Vehicle(s)/solvent(s) used: corn oil
- Justification for choice of solvent/vehicle: no data
- Concentration of test material in vehicle: no data
Duration of treatment / exposure:
72 hours
Frequency of treatment:
Daily during 3 days
Post exposure period:
24 hours after last dosing.
Doses / concentrations
Remarks:
Doses / Concentrations:
0; 47; 94; 187; 375; 750 mg/kg in corn oil
Basis:
nominal conc.
No. of animals per sex per dose:
5 males per dose
Control animals:
yes, concurrent no treatment
Positive control(s):
none

Examinations

Tissues and cell types examined:
bone marrow
Details of tissue and slide preparation:
CRITERIA FOR DOSE SELECTION: Doses extend up to the maximum tolerated dose.
TREATMENT AND SAMPLING TIMES ( in addition to information in specific fields): Based on the cell cycle and maturation times of the erythrocytes, harvesting of the bone marrow usually occurs 24 hours after the last dosing; this interval is indicated in the data tables as "sample collection time."

DETAILS OF SLIDE PREPARATION: The bone marrow is flushed from the femurs and spread onto slides. The slides are air-dried, fixed, and stained with a fluorescent DNA-specific stain that easily illuminates any micronuclei that may be present.

METHOD OF ANALYSIS: no data
Evaluation criteria:
Typically, 2000 polychromatic erythrocytes (PCEs, reticulocytes; immature erythrocytes) are scored per animal for frequency of micronucleated cells in each of 5 animals per dose group. In addition, the percentage of PCEs among the total erythrocyte population in the bone marrow is scored for each dose group as an indicator of chemical-induced toxicity. In non-treated healthy mice and rats, the %PCE in bone marrow is usually around 50-60%. If a chemical interferes with the production of erythrocytes in the bone marrow, then the %PCE in the bone marrow may decline from the typical normal level. Conversely, if erythrocyte production is stimulated by chemical exposure, then a higher percentage of immature erythrocytes may be observed.
Statistics:
no data

Results and discussion

Test results
Sex:
male
Genotoxicity:
negative
Toxicity:
no effects
Vehicle controls validity:
not specified
Negative controls validity:
not specified
Positive controls validity:
not specified

Applicant's summary and conclusion

Conclusions:
negative
Executive summary:

In the NTP report (1984), male mice (5 per dose) were exposed by i.p. route to ethylvanillin at doses 0; 47; 94; 187; 375; 750 mg/kg in corn oil for 72 hours. 2000 polychromatic erythrocytes were scored per animal for frequency of micronucleated cells.

Negative result was reported.