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
Year:
2014

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
Qualifier:
according to
Guideline:
EU Method B.13/14 (Mutagenicity - Reverse Mutation Test Using Bacteria)
GLP compliance:
yes (incl. certificate)
Type of assay:
bacterial reverse mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
other: yellow solid molten

Method

Species / strain
Species / strain:
S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and E. coli WP2
Metabolic activation:
with and without
Metabolic activation system:
S9 mix
Test concentrations with justification for top dose:
Dose range finding: up to 5000 µg/plate in the absence and presence of S9-mix in the strains TA100 and WP2uvrA
Main test: up to limited concentrations/plate because of observed toxicity in dose range finding.
Controls
Negative controls:
yes
Remarks:
DMSO
Solvent controls:
yes
Remarks:
DMSO
Positive controls:
yes
Positive control substance:
4-nitroquinoline-N-oxide
2-nitrofluorene
sodium azide
methylmethanesulfonate
other: ICR-191 (Acros Organics, Geel, Belgium); 2-aminoanthracene (only control with all strains in presence of S9 mix)

Results and discussion

Test resultsopen allclose all
Species / strain:
other: DOSE RANGE FINDING TEST: Salmonella typhimurium TA100 and Escherichia coli WP2uvrA
Metabolic activation:
with and without
Genotoxicity:
positive
Remarks:
TA100: in the absence and presence of S9-mix
Cytotoxicity:
yes
Remarks:
TA100: at 512 μg/plate and above in the absence of S9-mix and at 1600 and 5000 μg/plate in the presence of S9-mix; WP2uvrA: at 1600 and 5000 μg/plate in the absence and presence of S9-mix
Vehicle controls valid:
yes
Negative controls valid:
yes
Positive controls valid:
yes
Species / strain:
other: FIRST MAIN TEST: TA1535, TA1537 and TA98
Metabolic activation:
with and without
Genotoxicity:
positive
Remarks:
TA98: in the presence of S9-mix
Cytotoxicity:
yes
Remarks:
TA1535, TA1537 and TA98
Vehicle controls valid:
yes
Negative controls valid:
yes
Positive controls valid:
yes
Species / strain:
other: SECOND MAIN TEST: TA100, TA1535, TA1537, TA98 and WP2uvrA
Metabolic activation:
with and without
Genotoxicity:
positive
Remarks:
TA100: in the absence and presence of S9-mix; TA98: in the presence of S9-mix
Cytotoxicity:
yes
Remarks:
TA1535, TA1537 and TA98 in the absence of S9-mix and TA100 in the absence and presence of S9-mix
Vehicle controls valid:
yes
Negative controls valid:
yes
Positive controls valid:
yes
Species / strain:
other: THIRD MAIN TEST: TA1535, TA1537, TA98 and WP2uvrA
Metabolic activation:
with and without
Genotoxicity:
positive
Remarks:
TA98: in the presence of S9-mix
Cytotoxicity:
yes
Remarks:
all tester strains, except WP2uvrA in the presence of S9-mix
Vehicle controls valid:
yes
Negative controls valid:
yes
Positive controls valid:
yes
Species / strain:
other: FOURTH MAIN TEST: WP2uvrA
Metabolic activation:
with
Genotoxicity:
negative
Remarks:
in the presence of 10% (v/v) S9-mix and up to 5000 µg/plate
Cytotoxicity:
yes
Remarks:
in the presence of 10% (v/v) S9-mix and up to 5000 µg/plate
Vehicle controls valid:
yes
Negative controls valid:
yes
Positive controls valid:
yes

Any other information on results incl. tables

Since 1.7- to 2.9-fold, dose related increases were observed in two tester strains, in the absence (TA100) and presence of S9-mix (TA98 and TA100) and the results were reproducible in the repeat experiments, these increases are biologically relevant and the substance is considered to be mutagenic in the absence and presence of S9-mix.

All other bacterial strains showed negative responses over the entire dose range, i.e. no dose-related, increase in the number of revertants in follow-up experiments.

In this study, the negative and strain-specific positive control values were within the laboratory historical control data ranges indicating that the test conditions were adequate and that the metabolic activation system functioned properly.

Applicant's summary and conclusion

Conclusions:
Interpretation of results : positive