2-[2-[4-(diethylamino)phenyl]vinyl]-1,3,3-trimethyl-3H-indolium acetate

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:

1981

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1981

Report date:

1981

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

No E. coli strain tested

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

2-[2-[4-(diethylamino)phenyl]vinyl]-1,3,3-trimethyl-3H-indolium chloride

EC Number:

228-799-3

EC Name:

2-[2-[4-(diethylamino)phenyl]vinyl]-1,3,3-trimethyl-3H-indolium chloride

Cas Number:

6359-45-1

Molecular formula:

C23H29N2.Cl

IUPAC Name:

2-{2-[4-(diethylamino)phenyl]vinyl}-1,3,3-trimethyl-3H-indolium chloride

Test material form:

solid: particulate/powder

Details on test material:

Basic Violet 16

Method

Target gene:

Histidine locus

Species / strain

Species / strain 1

Species / strain / cell type:

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

Species / strain 2

Species / strain / cell type:

S. typhimurium TA 1538

Metabolic activation:

with and without

Metabolic activation system:

rat S9-mix

Test concentrations with justification for top dose:

Concentrations used: 2500, 500, 100, 20, and 4 µg/plate
Bacteriotoxic effects starting at 100 µg/plate without and 500 µg/plate with S9-mix

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: water
- Justification for choice of solvent/vehicle: good solubility of test substance

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

9-aminoacridine

other: MNNG, 4-Nitro-o-phenylendiamine, 2-aminoanthracene

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Preincubation: 0.1 mL TS+0.1 mL bacteria+0.5 mL S9+2 mL soft agar: 30 sec at 45 °C
- Incubation period: 48 hours at 37°C

NUMBER OF REPLICATIONS: 4 plates/strain/concentration

DETERMINATION OF CYTOTOXICITY
- Method: - background growth
- marked and dose-dependent reduction in mutant count compared to negative controls
- titer determination

Acceptance criteria:
a) The negative controls had to be within the expected range, as defined by published data (i.e. Maron and Ames, 1983) and the laboratory's own historical data
b) The positive controls had to show sufficient effects, as defined by the laboratory's experience
c) Titer determinations had to demonstrate sufficient bacterial density in the suspension.

An assay which did not comply with at least one of the above criteria was not used for assessment. Furthermore, the data generated in this assay needed to be confirmed by two additional independent experiments. Even if the criteria for points (a), (b) and (c) were not met, an assay was accepted if it showed mutagenic activity of the test compound.

Evaluation criteria:

A reproducible and dose-related increase in mutant counts of at least one strain is considered to be a positive result; this increase should be about twice the amount of controls.

Statistics:

N.A.

Results and discussion

Test results

Test results 1

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 2

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 3

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 4

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 5

Species / strain:

S. typhimurium TA 1538

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

There was a bacteriotoxic effect of the test item starting at 100 and 500 µg per plate without and with metabolic activation, respectively. No increase in mutation frequencies were observed in any strains.

All four strains concerned showed a dose related and biologically relevant increase in mutant counts over those of the negative controls. This applied both to both batches with and without S9 mix.

Applicant's summary and conclusion

Conclusions:

The test item showed no mutagenic effects under te conditions tested

Executive summary:

In a reverse gene mutation assay in bacteria, strains TA 100, TA 1537, TA 1535, TA 1538 and TA 98 of S. typhimurium were exposed to Basic Violet 16 at concentrations of up to 2500 µg/plate with and without metabolic activation.

There was a bacteriotoxic effect of the test item starting at 100 and 500 µg per plate without and with metabolic activation, respectively.

No evidence for mutagenic activity of Basic Violet 16 was found with or without metabolic activation.

 

The positive controls acted markedly mutagenic, as can be seen from the biologically relevant increase of mutant colonies compared with the corresponding negative control.