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Toxicological information

Genetic toxicity: in vitro

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Administrative data

Endpoint:
in vitro cytogenicity / chromosome aberration study in mammalian cells
Remarks:
Type of genotoxicity: chromosome aberration
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2005
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2005
Report Date:
2005

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
other: Test No. 487: In Vitro Mammalian Cell Micronucleus Test, OECD 26 Sep 2014
Deviations:
no
GLP compliance:
yes (incl. certificate)
Type of assay:
in vitro mammalian chromosome aberration test

Test material

Reference
Name:
Unnamed
Type:
Constituent

Method

Species / strain
Species / strain / cell type:
Chinese hamster lung fibroblasts (V79)
Details on mammalian cell type (if applicable):
- Type and identity of media: MEM supplemented with 10 % fetal calf serum- Properly maintained: yes- Periodically checked for Mycoplasma contamination: yes- Periodically checked for karyotype stability: yes
Metabolic activation:
with and without
Metabolic activation system:
Phenobarbital/ß-naphthoflavone induced rat liver S9 mix
Test concentrations with justification for top dose:
without S9 mix: 3.8 - 243 ug/mlwith S9 mix: 7.6 - 243 ug/ml
Vehicle / solvent:
DMSO
Controlsopen allclose all
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
ethylmethanesulphonate
other: colcemid
Remarks:
Without metabolic activation
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
cyclophosphamide
Remarks:
With metabolic activation
Details on test system and experimental conditions:
METHOD OF APPLICATION: in mediumDURATION- Exposure duration: 4 or 20h (see table 1)- Recovery: 4, 20, 28 or 44h (see table 1)- preparation interval: 24 or 48h (see table 1)For the micronucleus analysis the cultures of two flasks of each treatment group seeded and treated in parallel were trypsinised approx. 4 hours before the end of the recovery period and the cells were counted and then adhered in quadriperm dishes on slides for approx. 3 hours. Afterwards, the slides in the chambers of the quadriperm dishes were treated with a hypotonic solution (1.5 % [w/v] sodium citrate) for 5 min at 37° C. After incubation in the hypotonic solution the cells were fixed twice for < 1 min with a solution containing 3 parts ethanol, 1 part acetic acid and 1.25 % (v/v) formaldehyde. After preparation the cells were stained with May Grünwald and GiemsaNUMBER OF REPLICATIONS: in triplicateNumber of cells evaluated: 2000
Evaluation criteria:
A test substance can be classified as mutagenic if:- the number of micronucleated cells is not in the range of our historical control data (0.0 - 2.0 % micronucleated cells).and- either a concentration-related increase in three test groups or a significant increase of micronucleated cells in at least one test group is observed.A test substance can be classified as non-mutagenic if:- the number of micronucleated cells in all evaluated test groups is in the range of our historical control data (0.0 - 2.0 % micronucleated cells). and/or- no concentration-related increase in the number of micronucleated cells is observed.
Statistics:
Statistical significance can be confirmed by means of the Chi square test. However, both biological and statistical significance should be considered together. lf the criteria above mentioned for the test substance are not clearly met, the classification with regard to the historical data and the biological relevance is discussed and/or a confirmatory experiment is performed.

Results and discussion

Test results
Species / strain:
Chinese hamster lung fibroblasts (V79)
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
no cytotoxicity
Vehicle controls validity:
valid
Untreated negative controls validity:
valid
Positive controls validity:
valid
Additional information on results:
Test substance precipitation in culture medium 4 hrs alter start of treatment was observedwith 30.4 μg/mL and above in the absence and the presence of 89 mix in Experiment 1. InExperiment II, precipitation occurred alter treatment with 243 μg/mL in the absence of89 mix and with 121.5 μg/mL and above in the presence of 89 mix.In this study, in the absence and the presence of 89 mix, no clear cytotoxicity indicated byreduced cell numbers below 40 % of control was observed
Remarks on result:
other: all strains/cell types tested
Remarks:
Migrated from field 'Test system'.

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):negativeIn conclusion, it can be stated !hat under the experimental conditions reported, the test substance did not induce micronuclei in V79 cells (Chinese hamster cell line) in vitro in the absence and the presence of metabolic activation. Therefore, the test item has to be considered as non-mutagenic in this in vitro testsystem when tested up to the highest applicable test substance concentrations.