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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:
data from handbook or collection of data
Justification for type of information:
study supervised by the Food Chemistry Devision, Environmental Health Bureau, MHW, Japan

Data source

Reference
Reference Type:
publication
Title:
Micronucleus tests in mice on 39 food additives and eight miscellaneous chemicals
Author:
Hayashi M, Kishi M, Sofuni T, Ishidate jr. M
Year:
1988
Bibliographic source:
Fd. Chem. Toxic. 26, 487-500

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)
GLP compliance:
not specified
Type of assay:
other: micronucleus assay Type of genotoxicity: chromosome aberration

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
liquid
Specific details on test material used for the study:
All the samples in this study supplied from Japan Food Additives Association, Tokyo, at request of MHW, Japan, where purity and quality were checked.

Test animals

Species:
mouse
Strain:
other: ddY strain, obtained from Shizuoka Agricultural Cooperative Association for Laboratory Animals, Shizuoka, Japan
Sex:
male
Details on test animals and environmental conditions:
Eight-week-old male ddY mice (Shizuoka Agricultural Cooperative Association for Laboratory Animals. Shizuoka) were used at both laboratories and were allowed food pellets CE-2 (Japan Clea. Tokyo) and water ad libitum, throughout the experiments.

Administration / exposure

Route of administration:
intraperitoneal
Vehicle:
saline
Details on exposure:
The maximum doses were based on the LD50 at the supposed maximum tolerated dose. The sampling time after the administration was fixed at 24 hr.
Duration of treatment / exposure:
24 h
Frequency of treatment:
once
Post exposure period:
Animals were sacrificed 24 hours after injection.
Doses / concentrationsopen allclose all
Dose / conc.:
50 mg/kg bw/day
Dose / conc.:
100 mg/kg bw/day
Dose / conc.:
200 mg/kg bw/day
No. of animals per sex per dose:
6
Control animals:
yes, concurrent vehicle
Positive control(s):
Mitomycin C

Examinations

Tissues and cell types examined:
bone mallow cells
Details of tissue and slide preparation:
Femoral bone mallow cells were flushed out with foetal bovine serumand smeared on clean glass slides. Cells were fixed with methanol for 5 min and stained with Giemsa.
The preparations were coded and analysed without any knowledge of the treatment. 1000 polychromatic erythrocytes (PCE) per mouse were scored and the number of micronucleated PCEs (MNPCEs) recorded. The proportion of PCEs among the total erythrocytes were also evaluated.
Evaluation criteria:
Before evaluating the test data statistically the frequencies of MNPCEs in concurrent negative and positive controls were compared with the charts of historical control data to confirm the technical validity of the experiment.
A positive result was recorded onlv when one or more treatment group(s) showed a statistically significant difference (P < 0.01) from the spontaneous level of MNPCEs and the trend test indicated a positive dose response (P < 0.05).
Statistics:
A two-stage statistical procedure was used. In the first step of the procedure the frequency of MNPCEs in each treatment group was compared with the binomial distribution specified by historical control data. In the second step the dose-response relationship was tested by the Cochran-Armitage trend test.
A Monte-Carlo simulation study showed that the probability of a type I error in this two-step procedure was, in general closer to the nominal significance level (P = 0.01) than that of the usual conditional binomial test which has been widely used to evaluate micronucleus test data.

Results and discussion

Test results
Sex:
male
Genotoxicity:
negative
Toxicity:
no effects
Vehicle controls validity:
valid
Negative controls validity:
valid
Positive controls validity:
valid
Additional information on results:
Benzyl alcohol did not induce an increased number of micronuclei in polychromatic erythrocytes.

Any other information on results incl. tables

There was no indication of micronucleus induction at any dose tested.

 

 1 Dose (mg/kg)        MNPCE (%)        PCE (%)     Mortality 

 0                    0.23 +/-0.18      48.8 +/-6.2     0/6 

50                   0.23 +/-0.15      55.5 +/-4.0     0/6

100                 0.27 +/-0.12      51.8 +/-9.5     0/6

200                 0.12 +/-0.10      48.7 +/-5.2     0/6

 (4 doses)

100                 0.20 +/-0.14      63.1 +/-4.1     0/6 

Mitomycin C

 2.0                2.63 +/-0.32*     43.8 +/-1.1     0/6    

MNPCE = Micronucleated polychromatic erythrocyte

PCE = polychromatic erythrocyte

 * = (P < 0.01)

Applicant's summary and conclusion

Conclusions:
No evidence for mutagenicity.Benzyl alcohol did not induce an increased number of micronuclei in polychromatic erythrocytes..There was no indication of micronucleus induction at any dose tested.
Executive summary:

No evidence for mutagenicity. Benzyl alcohol did not induce an increased number of micronuclei in polychromatic erythrocytes..There was no indication of micronucleus induction at any dose tested.