3-(1H-benzimidazol-2-yl)-7-(diethylamino)-2-benzopyrone

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

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Data is from peer reviewed journal

Data source

Reference

Reference Type:

publication

Title:

Evaluation of Laser Dye Mutagenicity Using the Ames/Salmonella Microsome Test

Author:

Barbara J.Y. Wuebbles and James S. Felton

Year:

1985

Bibliographic source:

Environmental Mutagenesis 7511-522 (1985)

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: as per mentioned below

Principles of method if other than guideline:

Method as described by Ames et al 1975

GLP compliance:

not specified

Type of assay:

bacterial gene mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

3-(1H-benzimidazol-2-yl)-7-(diethylamino)-2-benzopyrone

EC Number:

248-451-4

EC Name:

3-(1H-benzimidazol-2-yl)-7-(diethylamino)-2-benzopyrone

Cas Number:

27425-55-4

Molecular formula:

C20H19N3O2

IUPAC Name:

3-(1H-benzimidazol-2-yl)-7-(diethylamino)-2-benzopyrone

Constituent 2

Reference substance name:

Coumarin 7

IUPAC Name:

Coumarin 7

Details on test material:

Details on test material
- Name of test material (as cited in study report): Coumarin 7
- Molecular formula (if other than submission substance): C20-H19-N3-O2
- Molecular weight (if other than submission substance): 333.389
- Substance type: Organic
- Physical state: Solid/powder
- Purity: No data available
- Impurities (identity and concentrations): contaminants present

Method

Target gene:

Histidine

Species / strain

Species / strain / cell type:

S. typhimurium, other: Salmonella typhimurium strains TA1538, TA98 and TA100

Details on mammalian cell type (if applicable):

Not applicable

Additional strain / cell type characteristics:

not specified

Metabolic activation:

with and without

Metabolic activation system:

no data

Test concentrations with justification for top dose:

0.1 mg/plate and 1 mg/plate

Vehicle / solvent:

DMSO

Controls

Untreated negative controls:

not specified

Negative solvent / vehicle controls:

not specified

True negative controls:

not specified

Positive controls:

not specified

Positive control substance:

not specified

Remarks:

no data

Details on test system and experimental conditions:

Details on test system and conditions
METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Preincubation period:
- Exposure duration: 2 days
- Expression time (cells in growth medium): 2 days
- Selection time (if incubation with a selection agent): No data available
- Fixation time (start of exposure up to fixation or harvest of cells): No data available

SELECTION AGENT (mutation assays): No data available
SPINDLE INHIBITOR (cytogenetic assays): No data available
STAIN (for cytogenetic assays): No data available

NUMBER OF REPLICATIONS: duplicate

NUMBER OF CELLS EVALUATED: No data available

DETERMINATION OF CYTOTOXICITY
- Method: mitotic index; cloning efficiency; relative total growth; other: No data available

OTHER EXAMINATIONS: No data available
- Determination of polyploidy: No data available
- Determination of endoreplication: No data available
- Other: No data available

OTHER: No data available

Evaluation criteria:

A sample was judged mutagenic if it produced greater than twice the spontaneous background colonies at more than one dose or at the highest dose tested.

Statistics:

No data available

Results and discussion

Test results

Species / strain:

S. typhimurium, other: Salmonella typhimurium strains TA1538, TA98 and TA100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

not specified

Untreated negative controls validity:

not specified

Positive controls validity:

not specified

Additional information on results:

Additional information on results
TEST-SPECIFIC CONFOUNDING FACTORS
- Effects of pH: No data available
- Effects of osmolality: No data available
- Evaporation from medium: No data available
- Water solubility: No data available
- Precipitation: No data available
- Other confounding effects: Less soluble in DMSO

RANGE-FINDING/SCREENING STUDIES: Spot test was performed with and without activation using the Salmonella typhimurium strains TA1538, TA98 and TA100. The spot test results were inconclusive. The dyes were than screened at 0.1 mg/plate and 1 mg/plate.

COMPARISON WITH HISTORICAL CONTROL DATA: No data available

ADDITIONAL INFORMATION ON CYTOTOXICITY: No data available

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 and without

The given test material does not induce gene toxicity in the Salmonella typhimurium strains TA1538, TA98 and TA100. Hence it is negative for gene mutation.

Executive summary:

Liquid-dye lasers are being used in a variety of applications because of their versatility. To date there is little information available on many such dyes since there has been minimal testing of their toxicity and mutagenicity. Because laser technology is an important part of a growing number of research and development procedures and the dyes are potentially genotoxic, special precautions and handling procedures may be required.

One of the families of dyes that are involved in the study is coumarins. Amongst the 12 coumarins studied, the test material Coumarin 7 is also studied for mutagenicity. Bacteria were grown overnight in Oxoid nutrient broth, then refrigerated at 4-5^OC for a few hours before use. 0.1 ml of bacterial culture was added to 2 ml of 45°C molten top agar containing 0.01 mg histidine HCI and 0.012 mg biotin/ml, followed by the test sample in ≤0.2 ml DMSO. Finally, 0.5 ml of sodium phosphate buffer, pH 7.4 (no activation), or 0.5 ml of Aroclor-induced rat S9 mixture was added, and the mixture was poured on minimal glucose agar plates. Histidine revertant colonies were counted on a Biotran II automated colony counter after a 2-day incubation at 37°C. A sample was judged mutagenic if it produced greater than twice the spontaneous background colonies at more than one dose or at the highest dose tested. To estimate mutagenic potency (revertant/µg) from linear dose-response curves, we used the method of Moore and Felton. All compounds were tested to a level at which they were toxic or to the limits of solubility. Duplicate plates were run on all tests except high-performance liquid chromatography (HPLC) fractions. All results were verified in repeat experiments. In the above mentioned study, coumarin 7, the test material failed to induce gene mutation in theSalmonella typhimuriumstrains TA1538, TA98 and TA100 with and without metabolic activation.

Thus the given test material, Coumarin 7, is negative for gene mutation in vitro.