o-anisidine

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Remarks:

Type of genotoxicity: gene mutation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 9 MAY 1984 to 11 MAY 1984

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Basic data given: comparable to guidelines

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

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

no

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

o-anisidine

EC Number:

201-963-1

EC Name:

o-anisidine

Cas Number:

90-04-0

Molecular formula:

C7H9NO

IUPAC Name:

2-methoxyaniline

Details on test material:

- Name of test material (as cited in study report): Echtrot BB Base flüssig

Method

Species / strain

Species / strain 1

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Additional strain / cell type characteristics:

other: auxotrophic for histidine

Species / strain 2

Species / strain / cell type:

S. typhimurium TA 1538

Additional strain / cell type characteristics:

other: auxotrophic for histidine

Species / strain 3

Species / strain / cell type:

E. coli WP2 uvr A

Additional strain / cell type characteristics:

other: auxotrophic for tryptophan

Metabolic activation:

with and without

Metabolic activation system:

rat liver S9 (Aroclor 1254 induced)

Test concentrations with justification for top dose:

0.004, 0.02, 0.1, 0.5, 2.5 and 10 µl/plate

Controls

Controls 1

Untreated negative controls:

yes

Negative solvent / vehicle controls:

no

Remarks:

, not required in this case

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 2-Aminoanthracene

Remarks:

with metabolic activation

Controls 2

Untreated negative controls:

yes

Negative solvent / vehicle controls:

no

Remarks:

, not required in this case

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 2-Aminoanthracene (all strains tested), 9-Aminoacridine (TA1537), Methylhydrazone derivative (TA98, TA1538, TA100), Streptocotocine (TA1535), ENNG (WP2 uvrA)

Remarks:

without metabolic activation

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Exposure duration: 2 days

NUMBER OF REPLICATIONS:
- 4 plates per strain and dose level, including the negative controls
- only 2 plates per strain and dose level for positive controls

Evaluation criteria:

positive: number of revertants is more than double the spontaneous mutations

Results and discussion

Test results

Test results 1

Species / strain:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

not applicable

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 2

Species / strain:

S. typhimurium TA 1538

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

not applicable

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 3

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

not applicable

Untreated negative controls validity:

valid

Positive controls validity:

valid

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

The test item "Echtrot BB Base flüssig" did not excert mutagenic activity in the reverse bacterial mutation assay (plate incorporation, maximum dose level 10 µl/plate) with or without metabolic activation.

Executive summary:

This study was performed to investigate the potential of "Echtrot BB Base flüssig" to induce gene mutations in the plate incorporation test using the Salmonella typhimurium strains TA 1535, TA 1537, TA 1538, TA 98, and TA 100, and the Escherichia coli strain WP2 uvrA. The assay was performed with and without liver microsomal activation. Each concentration, including the negative controls, was tested in quadruplicate. Positive controls were tested in duplicate. The test item was tested at the following concentrations: 0.004, 0.02, 0.1, 0.5, 2.5 and 10 µl /plate. No toxic effects, evident as a reduction in the number of revertants (below the indication factor of 0.5), were observed. No substantial increase in revertant colony numbers of any of the six tester strains was observed following treatment with "Echtrot BB Base flüssig" at any dose level, neither in the presence nor absence of metabolic activation (S9 mix). There was also no tendency of higher mutation rates with increasing concentrations in the range below the generally acknowledged border of biological relevance. Appropriate reference mutagens were used as positive controls and showed a distinct increase of induced revertant colonies. In conclusion, it can be stated that during the described mutagenicity test and under the experimental conditions reported, the test item did not induce gene mutations by base pair changes or frameshifts in the genome of the strains used.