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Toxicological information

Genetic toxicity: in vitro

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Administrative data

Endpoint:
in vitro gene mutation study in bacteria
Type of information:
experimental study
Adequacy of study:
weight of evidence
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
data from handbook or collection of data
Justification for type of information:
Data is from peer reviewed publication

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: Refer below principle
Principles of method if other than guideline:
Gene mutation study was performd to evaluate the mutagenic nature of the test compound Coumarin 30 using Salmonella typhimurium strain TA1538, TA98 and TA100
GLP compliance:
not specified
Type of assay:
bacterial gene mutation assay

Test material

Constituent 1
Reference substance name:
7-(diethylamino)-3-(1-methyl-1H-benzimidazol-2-yl)-2-benzopyrone
EC Number:
255-186-8
EC Name:
7-(diethylamino)-3-(1-methyl-1H-benzimidazol-2-yl)-2-benzopyrone
Cas Number:
41044-12-6
IUPAC Name:
7-(diethylamino)-3-(1-methyl-1H-benzimidazol-2-yl)-2H-chromen-2-one
Details on test material:
- Name of test material (as cited in study report): Coumarin 30
- Molecular formula (if other than submission substance): C21H21N3O2
- Molecular weight (if other than submission substance): 347.4159 g/mol
- Substance type: Organic
- Physical state: No data available
- Purity: No data available
- Impurities (identity and concentrations): No data available
Specific details on test material used for the study:
- Name of test material: Coumarin 30
- IUPAC name: 7-(diethylamino)-3-(1-methyl-1H-benzimidazol-2-yl)-2H-chromen-2-one
- Molecular formula: C21H21N3O2
- Molecular weight: 347.4159 g/mol
- Substance type: Organic

Method

Target gene:
Histidine
Species / strain
Species / strain / cell type:
S. typhimurium, other: TA1538, TA98 and TA100
Details on mammalian cell type (if applicable):
Not applicable
Additional strain / cell type characteristics:
not specified
Cytokinesis block (if used):
not specified
Metabolic activation:
with and without
Metabolic activation system:
S9 metabolic ativation system
Test concentrations with justification for top dose:
0.1 or 1 mg/plate
Vehicle / solvent:
- Vehicle(s)/solvent(s) used: DMSO
- Justification for choice of solvent/vehicle: the test chemical was soluble in 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
Details on test system and experimental conditions:
METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Preincubation period: No data available
- 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
Rationale for test conditions:
No data
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:
To estimate mutagenic potency (revertant/µg) from linear dose-response curves, the method of Moore and Felton was used

Results and discussion

Test results
Species / strain:
S. typhimurium, other: 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:
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: Almost insoluble 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: No mutagenic effects were observed

Applicant's summary and conclusion

Conclusions:
Coumarin 30 did not induce gene toxicity in the Salmonella typhimurium strains TA1538, TA98 and TA100 in the presence and absence of S9 metabolic activation system and hence it is negative for gene mutation in vitro.
Executive summary:

Gene mutation study was performd to evaluate the mutagenic nature of the test compound Coumarin 30 using Salmonella typhimurium strain TA1538, TA98 and TA100 with and without S9 metabolic activation system. Bacteria were grown overnight in Oxoid nutrient broth, then refrigerated at 4-5OC 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 0.1 or 1.0 mg/plate 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. Coumarin 30 did not induce gene toxicity in the Salmonella typhimurium strains TA1538, TA98 and TA100 in the presence and absence of S9 metabolic activation system and hence it is negative for gene mutation in vitro.