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Diss Factsheets

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:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: well performed OECD and GLP guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2001
Report date:
2001

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
Deviations:
no
GLP compliance:
yes
Type of assay:
bacterial reverse mutation assay

Test material

Constituent 1
Chemical structure
Reference substance name:
(3H)-benzofuran-2-one
EC Number:
209-052-0
EC Name:
(3H)-benzofuran-2-one
Cas Number:
553-86-6
Molecular formula:
C8H6O2
IUPAC Name:
2,3-dihydro-1-benzofuran-2-one
Details on test material:
- Name of test material (as cited in study report): 2-COUMARANONE
- Physical state: solid
- Analytical purity: >97%
- Lot/batch No.: A010242301
- Expiration date of the lot/batch: 2002-04-10
- Storage condition of test material: At room temperature in the dark

Method

Species / strain
Species / strain / cell type:
other: Salmonella typhimurium TA1535, TA1537, TA100 and TA98, Escherichia coli WP2uvrA
Details on mammalian cell type (if applicable):
not applicable
Additional strain / cell type characteristics:
other: Salmonella typhimurium TA1535, TA1537, TA100 and TA98, Escherichia coli WP2uvrA
Metabolic activation:
with and without
Metabolic activation system:
Aroclor-1254 induced rat liver S9-mix
Test concentrations with justification for top dose:
3, 10, 33, 100, 333, 1000, 3330, 5000 µg/plate
Vehicle / solvent:
ethanol
Controls
Untreated negative controls:
no
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
other: sodium azide, 9-aminoacridine, daunomycine, methylmethanesulfonate, 4-nitroquinoline-N-oxide, 2-aminoanthracene
Evaluation criteria:
A test substance is considered negative (not mutagenic) in the test if:
a) The total number of revertants in any tester strain at any concentration is not greater than two times the solvent control value, with or without metabolic activation.
b) The negative response should be reproducible in at least one independently repeated experiment.

A test substance is considered positive (mutagenic) in the test if:
a) It induces a number of revertant colonies, dose related, greater than two-times the number of revertants induced by the solvent control in any of the tester strains, either with or without metabolic activation.
However, any mean plate count of less than 20 is considered to be not significant.
b) The positive response should be reproducible in at least one independently repeated experiment.
The preceding criteria were not absolute and other modifying factors might enter into the final evaluation decision.

Results and discussion

Test results
Species / strain:
other: Salmonella typhimurium TA1535, TA1537, TA100 and TA98, Escherichia coli WP2uvrA
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
no cytotoxicity
Remarks:
- i.e. no reduction of the bacterial background lawn and no biologically relevant decrease in the number of revertants were observed.
Vehicle controls validity:
valid
Untreated negative controls validity:
not applicable
Positive controls validity:
valid
Remarks on result:
other: all strains/cell types tested
Remarks:
Migrated from field 'Test system'. Remarks: Salmonella typhimurium TA1535, TA1537, TA100 and TA98, Escherichia coli WP2uvrA

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):
negative

Based on the results of this study it is concluded that 2-COUMARANONE is not mutagenic in the Salmonella typhimurium reverse mutation assay and in the Escherichia coli reverse mutation assay.
Executive summary:

2-COUMARANONE was tested in the Salmonella typhimurium reverse mutation assay with four histidine-requiring strains of Salmonella typhimurium (TA1535, TA1537, TA100 and TA98) and in the Escherichia coli reverse mutation assay with a tryptophan-requiring strain of Escherichia colt WP2uvrA. The test was performed in two independent experiments in the presence and absence of S9-mix (Aroclor-1254 induced rat liver S9-mix). 2-COUMARANONE was tested up to concentrations of 5000 µg/plate in the absence and presence of S9-mix.

2-COUMARANONE did not precipitate on the plates at this dose level. The bacterial background lawn was not reduced at all concentrations tested and no biologically relevant decrease in the number of revertants was observed. The presence of 5 and 10% (v/v) liver microsomal activation did not influence these findings. 2-COUMARANONE did not induce a dose-related, two-fold increase in the number of revertant (His+) colonies in each of the four tester strains (TA1535, TA1537, TA98 and TA100) and in the number of revertant (Trp+) colonies in tester strain WP2uvrA both in the absence and presence of S9-metabolic activation. These results were confirmed in independently repeated experiments.

Based on the results of this study it is concluded that 2-COUMARANONE is not mutagenic in the Salmonella typhimurium reverse mutation assay and in the Escherichia coli reverse mutation assay.