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Toxicological information

Genetic toxicity: in vitro

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Administrative data

Endpoint:
in vitro gene mutation study in bacteria
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1979
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
guideline study with acceptable restrictions
Remarks:
TA102 strain is missing
Justification for type of information:
In addition to the Ames test on Dihydromyrcenyl acetate, Ames information from Dihdyromyrcenol is added to make up for the missing TA102 strain. The read across rationale is presented in the Genetic toxicity Endpoint summary, the accompanying files are also attached there.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1979
Report date:
1979

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
other: Ames test method et al. (1975)
Version / remarks:
Ames test method et al. (1975)
GLP compliance:
no
Remarks:
conduected prior to the GLP guideline
Type of assay:
bacterial forward mutation assay

Test material

Constituent 1
Chemical structure
Reference substance name:
2,6-dimethyloct-7-en-2-yl acetate
EC Number:
258-751-7
EC Name:
2,6-dimethyloct-7-en-2-yl acetate
Cas Number:
53767-93-4
Molecular formula:
C12H22O2
IUPAC Name:
2,6-dimethyloct-7-en-2-yl acetate
Test material form:
liquid

Method

Species / strainopen allclose all
Species / strain / cell type:
S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Species / strain / cell type:
S. typhimurium TA 98
Metabolic activation:
with and without
Test concentrations with justification for top dose:
0, 0.008, 0.04, 0.2, 1.0 and 5.0 microL/plate
Vehicle / solvent:
Appropriate dilutions in DMSO were prepared immediately before use.
Controls
Untreated negative controls:
yes
Positive controls:
yes
Positive control substance:
not specified
Details on test system and experimental conditions:
2 ml molten soft agar were added to 0.1 mL of a fully grown culture of one of the tester strains and 0.1 mL of the appropriate dilution /suspension of the test compound (and 0.5 mL of the S-9 mix if indicated). The ingredients were thoroughly mixed and immediately poured into minimal glucose agar plates. After the top agar had been allowed to harden, the plates were incubated at 37°C for two days. Then the colonies (revertants which are histidine-independant) were counted, and the background lawn of baterial growth examined microscopically. All determination were made in triplicate and appropriate controls were included in each assay.

Results and discussion

Test results
Key result
Species / strain:
other: S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
cytotoxicity
Remarks:
at 1.0 and 5.0 microL/plate DHMA was clearly toxic to strains TA1537, TA1538, TA98 and TA100 in the absence of S9
Vehicle controls validity:
not valid
Positive controls validity:
valid
Additional information on results:
Incorporation of 0.008 up to 0.5 - 0.5 microL of the test liquid par plate did not induce an increase in the number of his +revertants with any of the five tester strains either in the presence ot absence of S-9 mix. At 1.0 and 5.0 microL/plate DHMA was clearly toxic to strains TA1537, TA1538, TA98 and TA100 in the basence of S9 mix as revealed by a less dense background lawn of bacterial growth.

Applicant's summary and conclusion

Conclusions:
From the present results it can be concluded that the substance up to non- inhibitory levels did not reveal any mutagenic activity in the plate incorporation assay with S.Typhimurium TA1535, TA1537, TA1538, TA98 or TA100 in the presence or absence of the liver microsome activation system under the test condition employed in this evaluation.
Executive summary:

The mutagenic activity of the substance was examined in the Salmonella/microsome mutagenicity test, using a set of five histidine requiring mutants of S. Typhimurium (TA1535, TA1537, TA1538, TA98 and TA100) and liver homogenate of Aroclor induced rats. Incorporation of the test liquid up to non-inhibitory levels i.e. 0.2 - 5.0 microl/plate did not increase the number of his +revertants in any of the five tester strains either in the presence or in the absence of the liver microsome activation system.

It was concluded that the present results did not reveal any mutagenic activity of the test material in the Salmonella/microsome metagenicity test.