2,2'-[(3,3'-dichloro[1,1'-biphenyl]-4,4'-diyl)bis(azo)]bis[N-(2-methylphenyl)-3-oxobutyramide]

Genetic toxicity: in vitro

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

Test material information

Constituent 1

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)

Controls

Controls 1

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

Controls 2

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 results

Test results 1

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

Test results 2

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.