Registration Dossier

Toxicological information

Genetic toxicity: in vitro

Currently viewing:

Administrative data

Endpoint:
in vitro gene mutation study in mammalian cells
Remarks:
Type of genotoxicity: gene mutation
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Study period:
1984
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Equivalent or similar to OECD Guideline 476.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1984
Report Date:
1984

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 476 (In Vitro Mammalian Cell Gene Mutation Test)
GLP compliance:
not specified
Type of assay:
mammalian cell gene mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent

Method

Target gene:
TK locus
Species / strain
Species / strain / cell type:
mouse lymphoma L5178Y cells
Details on mammalian cell type (if applicable):
na
Metabolic activation:
with and without
Metabolic activation system:
S9 homogenate
Test concentrations with justification for top dose:
Without activation: 6.25 nl/ml to 37.5 nl/ml
With activation: 3.91 nl/ml to 62.5 nl/ml
Vehicle / solvent:
- Vehicle(s)/solvent(s) used: [ethanol]
- Justification for choice of solvent/vehicle:The test material was miscible with ethanol.
Controls
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
True negative controls:
not specified
Positive controls:
yes
Positive control substance:
ethylmethanesulphonate
Details on test system and experimental conditions:
METHOD OF APPLICATION: in medium

DURATION
- Exposure duration: 4 hours
- Expression time (cells in growth medium): 24 hours

SELECTION AGENT (mutation assays): BrdU

NUMBER OF REPLICATIONS: Variable with or without activation

NUMBER OF CELLS EVALUATED: 3x10^6

DETERMINATION OF CYTOTOXICITY
- Method: cloning efficiency

Results and discussion

Test results
Species / strain:
mouse lymphoma L5178Y cells
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
cytotoxicity
Remarks:
None of the assayed treatments induced a mutant frequency that exceeded the minimum criterion of 40.8 x 10^-6
Vehicle controls validity:
valid
Untreated negative controls validity:
valid
Positive controls validity:
valid
Additional information on results:
The test material induced a good range of toxicities for evaluation of the test material (percent relative growths, 65.3% to 2.8%). The toxicities did show some variability between replicate samples. In the presence of metabolic activation, no indication of mutagenic activity was observed. The average cloning efficencies for the solvent and untreated negative controls varied from 119.1% without activation to 82.7% with activation which demonstrated very good cloning conditions for the assays. The negative control mutant frequencies were all in the normal range and the positive compounds yielded normal mutant frequencies that were greatly in excess of the background.
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):
negative with metabolic activation
negative without metabolic activation

It is concluded in this study that the test material is not a mutagenic agent with or without activation. Classification is not warranted under the new Regulation (EC) 1272/2008 on classification, labeling, and packaging of substances and mixtures (CLP) or under the Directive 67/518/EEC for dangerous substances and Directive 1999/45/EC for preparations.
Executive summary:

The test material was examined for mutagenic activity in the mouse lymphoma forward mutation assay in the absence and presence of a liver S9 fraction for metabolic activation. The test material did not induce significant increases in the mutant frequency at the TK locus in L5178Y mouse lymphoma cells. Treatments up to 37.5 nl/ml without activation and 62.5 nl/ml with activation were assayed and high toxicities were induced without inducing significant increases in the mutant frequency. It is concluded in this study that the test material is not a mutagenic agent with or without activation. Classification is not warranted under the new Regulation (EC) 1272/2008 on classification, labeling, and packaging of substances and mixtures (CLP) or under the Directive 67/518/EEC for dangerous substances and Directive 1999/45/EC for preparations.