Registration Dossier

Toxicological information

Genetic toxicity: in vivo

Currently viewing:

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:
no data available
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions
Remarks:
Comparable to OECD Guideline 474. Deficiencies were: only four animals tested per dose; bone marrow taken only once, six hours after final treatment; only 1000 erythrocytes scored per animal

Data source

Reference
Reference Type:
publication
Title:
STUDY OF ARTIFICIAL FLAVOURING SUBSTANCES FOR MUTAGENICITY IN THE SALMONELLA/MICROSOME, BASC AND MICRONUCLEUS TESTS
Author:
Wild, D., King, M. T., and Gocke
Year:
1983
Bibliographic source:
Food and Chemical Toxicology Vol 21., No. 6, pp 707-719.

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)
Deviations:
yes
Remarks:
4 animals/dose (guideline recommends ≥ 5/sex/dose); bone marrow taken once, 6 h after final treatment (guideline recommends taking twice, 18-24 and 36-48 h after final treatment); 1000 erythrocytes scored (guideline recommends ≥ 2000)
GLP compliance:
not specified
Type of assay:
micronucleus assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
liquid
Specific details on test material used for the study:
Source: ICN-K &K (Plainview, NY, USA)

Test animals

Species:
mouse
Strain:
NMRI
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: lvanovas GmbH (Kisslegg)
- Age at study initiation: 10 to 14 weeks
- Weight at study initiation: no data available
- Assigned to test groups randomly: no data available
- Fasting period before study: no data available
- Housing: no data available
- Diet (e.g. ad libitum): standard chow (Altromin) ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: no data available

ENVIRONMENTAL CONDITIONS
- Temperature (°C): no data available
- Humidity (%): no data available
- Air changes (per hr): no data available
- Photoperiod (hrs dark / hrs light): no data available

IN-LIFE DATES: no data available

Administration / exposure

Route of administration:
intraperitoneal
Vehicle:
- Vehicle(s)/solvent(s) used: olive oil
- Justification for choice of solvent/vehicle: no data available
- Concentration of test material in vehicle: no data available
- Purity: no data available
Details on exposure:
intraperitoneal injections
Duration of treatment / exposure:
single injections at 0 and 24 h
Frequency of treatment:
once daily, for 2 days
Post exposure period:
6 hours
Doses / concentrations
Remarks:
Doses / Concentrations:
438, 292 or 146 mg/kg bw/day
Basis:
no data
No. of animals per sex per dose:
probably 2 [4 animals/dose tested]
Control animals:
other: yes: concurrent negative controls (possibly given vehicle or no treatment)
Positive control(s):
no data
- Justification for choice of positive control(s): no data available
- Route of administration: no data available
- Doses / concentrations: no data available

Examinations

Tissues and cell types examined:
bone marrow micronucleated polychromatic erythrocytes
Details of tissue and slide preparation:
CRITERIA FOR DOSE SELECTION: no data available

TREATMENT AND SAMPLING TIMES (in addition to information in specific fields): treatment at 0 and 24 hours, sampling at 30 hours

DETAILS OF SLIDE PREPARATION: stained with May-Gruenwald and Giemsa stains. 1000 polychromatic erythrocytes analysed for each animal on coded slides.

METHOD OF ANALYSIS: no data available
Evaluation criteria:
no data available
Statistics:
no data available

Results and discussion

Test results
Key result
Sex:
male/female
Genotoxicity:
negative
Toxicity:
not specified
Vehicle controls valid:
other: possibly negative control
Negative controls valid:
yes
Positive controls valid:
not specified
Additional information on results:
RESULTS OF RANGE-FINDING STUDY
- Dose range: no data available
- Solubility: no data available
- Clinical signs of toxicity in test animals: no data available
- Evidence of cytotoxicity in tissue analyzed: no data available
- Rationale for exposure: no data available
- Harvest times: no data available
- High dose with and without activation: no data available

RESULTS OF DEFINITIVE STUDY
- Induction of micronuclei (for Micronucleus assay): no data available
- Ratio of PCE/NCE (for Micronucleus assay): 1.7, 2.0 and 2.2 per thousand (for animals given 438, 292 and 146 mg/kg bw/day respectively). 2.0 per thousand for negative control.
- Appropriateness of dose levels and route: no data available
- Statistical evaluation: no data available

Applicant's summary and conclusion

Conclusions:
Interpretation of results: negative
In an in vivo bone marrow micronucleus test, similar to that recommended by OECD Guideline 474, no consistent evidence of mutagenic activity was observed in mice following intraperitoneal injections of α-methylcinnamaldehyde at up to 438 mg/kg bw/day for 2 days.
Executive summary:

A publication briefly describes an in vivo micronucleus test carried out on groups of mice, conducted using a protocol similar to OECD Guideline 474.

Groups of four mice were given two intraperitoneal injections (at 0 and 24 hours) of α-methylcinnamaldehyde at 146, 292 or 438 mg/kg bw/day. Six hours after the final injection, mice were killed, and bone-marrow smears were prepared. Following fixation and staining, 1000 polychromatic erythrocytes were analysed from each animal, and the number of micronucleated polychromatic erythrocytes was recorded.

Treatment with α-methylcinnamaldehyde did not significantly induce increased numbers of micronuclei. Under the conditions of this assay, no convincing evidence of mutagenic activity was demonstrated for α-methylcinnamaldehyde.