Registration Dossier

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)

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Report date:
2003

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
GLP compliance:
yes (incl. QA statement)
Type of assay:
bacterial reverse mutation assay

Test material

Constituent 1
Chemical structure
Reference substance name:
2,2-difluoro-1,3-benzodioxole
EC Number:
216-431-4
EC Name:
2,2-difluoro-1,3-benzodioxole
Cas Number:
1583-59-1
Molecular formula:
C7H4F2O2
IUPAC Name:
2,2-difluoro-2H-1,3-benzodioxole

Method

Target gene:
hystidine
Species / strain
Species / strain / cell type:
S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA 102
Additional strain / cell type characteristics:
not specified
Metabolic activation:
with and without
Metabolic activation system:
S9 Mix
Test concentrations with justification for top dose:
Exp. I and Exp. II without S9 mix: 33, 100, 333, 1000, 2500, 5000 ug/plate
Exp. II with S9 mix: 33, 100, 333, 666, 1000, 1750, 2500, 5000 ug/plate
Confirmatory Exp.: 33, 100, 333, 500, 1000, 1500, 2500, 5000 ug/plate

Results and discussion

Test results
Species / strain:
S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA 102
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
cytotoxicity
Additional information on results:
Slight toxic effects, evident as a reduction in the number of revertants, were observed in strain TA 1535 at 5000 ug/plate and in strain TA102 at 1000 ug/plate and above in the presence of S9 mix in exp. I. In exp. II, slight toxic effects were observed with metabolic activation in strains TA 1537, TA98, TA 100 at 5000 ug/plate and in strain TA 102 at 2500 and 5000 ug/plate.
No substantial increase in revertant colony numbers of any of the five tester strains was observed following treatment at any dose level, neither with or without metabolic activation.
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

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.
Therefor it is considered to be non-mutagenic in this Salmonella thypimurium reverse mutation assay.