Registration Dossier

Administrative data

Endpoint:
in vivo mammalian somatic and germ cell study: gene mutation
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:
Data is from peer reviewed publication

Data source

Reference
Reference Type:
publication
Title:
Gene mutation toxicity study of the test chemical
Author:
Franzios et al
Year:
1997
Bibliographic source:
J. Agric. Food Chem.

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
other: Refer below principle
Principles of method if other than guideline:
Gene mutation toxicity study was performed to determine the mutagenic nature of the test chemical using D. melanogaster strains
GLP compliance:
not specified
Type of assay:
other: Wing somatic mutation and recombination tests (SMART)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
liquid
Details on test material:
- Name of test material (IUPAC name): (2R,5S)-5-methyl-2-(propan-2-yl)cyclohexan-1-one- Common name: Menthone - Molecular formula: C10H18O- Molecular weight: 154.2512 g/mol- Smiles notation: C1([C@@H](CC[C@@H](C1)C)C(C)C)=O- InChl: 1S/C10H18O/c1-7(2)9-5-4-8(3)6-10(9)11/h7-9H,4-6H2,1-3H3- Substance type: Organic- Physical state: Liquid

Test animals

Species:
Drosophila melanogaster
Strain:
other: The multiple wing hair strain (mwh), with genetic constitution mwh e/mwh e and the flare (flr3) strain with genetic constitution y wco/y wco; flr3 se/TM2 Ubx130 se e. Larvae from the cross between flr3 virgin females with mwh males were used for testing
Details on species / strain selection:
No data
Sex:
male/female
Details on test animals and environmental conditions:
No data

Administration / exposure

Route of administration:
not specified
Vehicle:
Ringer solution
Details on exposure:
No data
Duration of treatment / exposure:
18 hrs
Frequency of treatment:
No data
Post exposure period:
No data
Doses / concentrations
Remarks:
The concentration selected for the study was slightly above the crucial dose of each individual compound that causes death to 50% of the tested larvae (LD50: 1.29 menthone).
No. of animals per sex per dose:
No data
Control animals:
yes, concurrent vehicle
Positive control(s):
No data

Examinations

Tissues and cell types examined:
Wings
Details of tissue and slide preparation:
Details of tissue and slide preparationCRITERIA FOR DOSE SELECTION: No dataTREATMENT AND SAMPLING TIMES ( in addition to information in specific fields): Eggs from the Drosophila cross mentioned above were collected during an 8 h period, and72 (4 h later the larvae were removed from the food. Groups of 50 larvae, after washing with 17% NaCl solution, were transferred to individual Petri dishes (9 cm diameter) containing a Whatman 3 mm paper moistened with Ringer solution and exposed to various amounts of the examined compound. Different amounts of EOs or their components were applied to a small filter paper disk (4 mm). Dishes were kept at 24 ± 1°C and 60% humidity for 18 h. After the exposure period, the larvae were washed with Ringer solution and transferred tonew individual vials with food until emergence of adult fliesDETAILS OF SLIDE PREPARATION: The trans-heterozygous (mwh/flr3) female flies that emerged from the cross were selected and stored in 70% ethanol-glycerol (1:1). Their wings were mounted in Euparal solution and scored at 400X magnification for the presence of mosaic spots. METHOD OF ANALYSIS: On the basis of the size, the number, and the type of cells showing malformed wing hairs, different categories of spots were recorded by following the methods and criteria of Graf et al.OTHER: No data
Evaluation criteria:
No data
Statistics:
For statistical analysis of the genotoxic effects of the tested compounds, the spots were grouped into four categories: (a) small single spots (with one or two affected cells, either mwh or flr3), (b) large single spots (with three or more affected cells, either mwh or flr3), (c) twin spots (consisting of both mwh and flr3 subclones), and (d) total single spots. For the statistical significance of the results, the multiple-decision procedure was used. The procedure is based on the conditional binomial test and the X2 test (K. Pearson’s criterion). Each statistical test was carried out at 5% significance level.

Results and discussion

Test results
Sex:
female
Genotoxicity:
positive
Toxicity:
not specified
Vehicle controls valid:
yes
Negative controls valid:
not specified
Positive controls valid:
yes
Additional information on results:
No data

Any other information on results incl. tables

Table. Summary of Results Obtained in the Wing Somatic Mutation and Recombination Test (SMART) on D. melanogaster after Treatment with the Essential Oils (EOs) of Menthone

Treatment

Wings analyzed

Spots per wing (no. of spots) diagnosis

small single spots

(1-2 cells) m : 2.0

(large single spots

(>2 cells) m : 5.0

twin spots

m : 5.0

total spots

m : 2

1.3µL

62

1.48 (92) +

0.13 (8) i

0.09 (6) -

1.71 (106) +

control (ringer)

74

0.74 (55)

0.06 (5)

0.08 (6)

0.89 (66)

Applicant's summary and conclusion

Conclusions:
The test chemical is considered to be potent mutagenic but not recombinogenic inducer based on the observations made using D. melanogaster flr3 X mwh crosses.
Executive summary:

Gene mutation toxicity study was performed to determine the mutagenic nature of the test chemical using D. melanogaster strains. The study was performed using D. melanogaster. Themultiple wing hair strain (mwh), with genetic constitution mwh e/mwh e and the flare (flr3) strain with genetic constitution y wco/y wco; flr3se/TM2 Ubx130se e were used for the study. Larvae from the cross between flr3virgin females with mwh males were used for testing. The concentration selected for the study was slightly above the crucial dose of each individual compound that causes death to 50% of the tested larvae (LD50: 1.29). Eggs from the Drosophila cross mentioned above were collected during an 8 h period, and 72 (4 h later the larvae were removed from the food. Groups of 50 larvae, after washing with 17% NaCl solution, were transferred to individual Petri dishes (9 cm diameter) containing a Whatman 3 mm paper moistened with Ringer solution and exposed to various amounts of the examined compound. Different amounts of EOs or their components were applied to a small filter paper disk (4 mm). Dishes were kept at 24±1°C and 60% humidity for 18 h. After the exposure period, the larvae were washed with Ringer solution and transferred to new individual vials with food until emergence of adult flies. The trans-heterozygous (mwh/flr3) female flies that emerged from the cross were selected and stored in 70% ethanol-glycerol (1:1). Their wings were mounted in Euparal solution and scored at 400X magnification for the presence of mosaic spots. On the basis of the size, the number, and the type of cells showing malformed wing hairs, different categories of spots were recorded by following the methods and criteria of Graf et al. The test chemical is considered to be potent mutagenic but not recombinogenic inducer based on the observations made using D. melanogaster flr3X mwh crosses.