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Toxicological information

Genetic toxicity: in vitro

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Administrative data

Endpoint:
in vitro gene mutation study in mammalian cells
Remarks:
Type of genotoxicity: gene mutation
Type of information:
experimental study
Adequacy of study:
key study
Study period:
no data
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference
Reference Type:
publication
Title:
Unnamed
Year:
1984

Materials and methods

Test guideline
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 476 (In Vitro Mammalian Cell Gene Mutation Test)
Principles of method if other than guideline:
Mouse Lymphoma Study
GLP compliance:
not specified
Type of assay:
mammalian cell gene mutation assay

Test material

Constituent 1
Chemical structure
Reference substance name:
2,2'-[(3,3'-dichloro[1,1'-biphenyl]-4,4'-diyl)bis(azo)]bis[3-oxo-N-phenylbutyramide]
EC Number:
228-787-8
EC Name:
2,2'-[(3,3'-dichloro[1,1'-biphenyl]-4,4'-diyl)bis(azo)]bis[3-oxo-N-phenylbutyramide]
Cas Number:
6358-85-6
Molecular formula:
C32H26Cl2N6O4
IUPAC Name:
2,2'-[(3,3'-dichlorobiphenyl-4,4'-diyl)didiazene-2,1-diyl]bis(3-oxo-N-phenylbutanamide)
Test material form:
not specified

Method

Target gene:
thymidine kinase locus
Species / strain
Species / strain / cell type:
mouse lymphoma L5178Y cells
Additional strain / cell type characteristics:
not specified
Metabolic activation:
with and without
Metabolic activation system:
S9 from the livers of either Aroclor 1254-induced or non-induced male Fischer 344 rats
Test concentrations with justification for top dose:
0.0312, 0.0625, 0.125, 0.25, 0.5 µg/ml (Nonactivation Trial 1)
0.1, 0.2, 0.3, 0.4, 0.5 (Nonactivation Trial 2; Induced S9 Trial 1, 2, 3)
Vehicle / solvent:
- Vehicle(s)/solvent(s) used: dimethylsulfoxide (DMSO)

Controlsopen allclose all
Untreated negative controls:
no
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
other: methylmethanesulfonate, ethylmethanesulphonate
Remarks:
without metabolic activation
Untreated negative controls:
no
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
3-methylcholanthrene
Remarks:
with metabolic activation
Details on test system and experimental conditions:
METHOD OF APPLICATION: in medium

DURATION
- Exposure duration: 4 h
- Expression time (cells in growth medium): 48 h
- Selection time (if incubation with a selection agent): 10-12 days


SELECTION AGENT (mutation assays): trifluorothymidine


NUMBER OF REPLICATIONS: all treatment levels within an experiment were performed in duplicate; experiments were performed twice (nonactivated) or in triplicate (S9)


DETERMINATION OF CYTOTOXICITY
- Method: cloning efficiency
Statistics:
statistical analysis for trend and peak responses

Results and discussion

Test resultsopen allclose all
Key result
Species / strain:
mouse lymphoma L5178Y cells
Metabolic activation:
without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
no cytotoxicity
Vehicle controls validity:
valid
Untreated negative controls validity:
not examined
Positive controls validity:
valid
Key result
Species / strain:
mouse lymphoma L5178Y cells
Metabolic activation:
with
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
no cytotoxicity
Vehicle controls validity:
valid
Untreated negative controls validity:
not examined
Positive controls validity:
valid
Remarks on result:
other: all strains/cell types tested

Any other information on results incl. tables

- results without metabolic activation were negative in two replicates, the tested concentrations were non-toxic

Trial 1 (mean mutant frequency): 36, 40, 44, 40 and 46 at 0.03, 0.06, 0.125, 0.25 and 0.5 µg/ml; DMSO control: 31

Trial 2 (mean mutant frequency): 30, 30, 45, 38 and 37 at 0.1, 0.2, 0.3, 0.4 and 0.5 µg/ml; DMSO control: 30

- with metabolic activation one trial revealed increased mutant frequencies at concentrations >/= 0.2 µg/ml in comparison to the vehicle control, but without dose response relationship; in two further trials negative responses were observed

Trial 1 (mean mutant frequency): 25, 61, 68, 69 and 62 at 0.1, 0.2, 0.3, 0.4 and 0.5 µg/ml; DMSO control: 30

Trial 2 (mean mutant frequency): 48, 57, 62, 61 and 60 at 0.1, 0.2, 0.3, 0.4 and 0.5 µg/ml; DMSO control: 54

Trial 3 (mean mutant frequency): 79, 68, 76, 94 and 88 at 0.1, 0.2, 0.3, 0.4 and 0.5 µg/ml; DMSO control: 71

- solvent and positve controls were within the normal range

Applicant's summary and conclusion

Conclusions:
Interpretation of results:
negative with metabolic activation
negative without metabolic activation

The test item did not induce mammalian cell gene mutations under the conditions tested.

Executive summary:

Induction of mammalian cell gene mutations in vitro has been investigated in mouse lymphoma L5178Y cells in the presence (rat liver S9) and absence of metabolic activation. The test item did not induce gene mutations in concentrations up to 0.5 µg/ml under the tested conditions.