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:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: GLP compliant guideline study, available as unpublished report, restriction in design (no E.coli WP2 or S.typhimurium TA 102 used and only one positive control used to test efficacy of the S9-mix), but adequate for assessment

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1994
Report Date:
1994

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
Deviations:
yes
Remarks:
, no E.coli WP2 or S.typhimurium TA 102 used and only one positive control used to test efficacy of the S9-mix
Qualifier:
according to
Guideline:
EU Method B.13/14 (Mutagenicity - Reverse Mutation Test Using Bacteria)
Deviations:
yes
Remarks:
, no E.coli WP2 or S.typhimurium TA 102 used and only one positive control used to test efficacy of the S9-mix
GLP compliance:
yes
Type of assay:
bacterial reverse mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of the test substance used in the study report: Asta-C9-Diol-Natrium
- Appearance, consistency: Redbrown liquid
- Storage: Refrigerator (protected from light)

Method

Species / strain
Species / strain / cell type:
S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Metabolic activation:
with and without
Metabolic activation system:
Aroclor induced rat liver S-9 mix
Test concentrations with justification for top dose:
1562.5, 3125, 6250, 12500, 25000 µg/plate
Vehicle / solvent:
aqua dest.
Controlsopen allclose all
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
other: 2-aminoanthracene
Remarks:
with S-9 mix for all strains
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
other: N-methyl-N'-nitro-N-nitrosoguanidine
Remarks:
without S-9 mix for strains 100 and TA 1535
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
other: 4-nitro-o-phenylendiamine
Remarks:
without S-9 mix for strain TA 98
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
other: 9-aminoacridine chloride monohydrate
Remarks:
without S-9 mix for strain TA 1537
Details on test system and experimental conditions:
EXPERIMENT 1
- METHOD OF APPLICATION: in agar (plate incorporation)
- DURATION: Exposure duration: 48 h
- NUMBER OF REPLICATIONS: 3 test plates per dose or per control
- DETERMINATION OF CYTOTOXICITY: Toxicity detected by a reduced his- background growth, decrease in the number of his+ revertants

EXPERIMENT 2 and 3
- METHOD OF APPLICATION: preincubation
- DURATION: Preincubation period: 20 min; Exposure duration: 48 h
- NUMBER OF REPLICATIONS: 3 test plates per dose or per control
- DETERMINATION OF CYTOTOXICITY: Toxicity detected by a reduced his- background growth, decrease in the number of his+ revertants
Evaluation criteria:
In general, a substance to be characterized as positive in the Ames test has to fulfill the following requirements:
- doubling of the spontaneous mutation rate (control)
- dose-response relationship
- reproducibility of the results

Results and discussion

Test results
Species / strain:
S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
no cytotoxicity
Vehicle controls validity:
valid
Untreated negative controls validity:
valid
Positive controls validity:
valid
Additional information on results:
No test substance precipitation was found.
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

According to the results of the present study, the test substance is not mutagenic in the Ames test under the experimental conditions chosen here.
Executive summary:

In a GLP compliant mutagenicity test, performed according to OECD guideline 471, 4 Salmonella typhimurium strains (TA 1535, TA 1537, TA 98, and TA 100) were used to test the mutagenic potential of the test substance both with and without metabolic activation. Two experiments were performed; a standard plate test and preincubation test, respectively. In both tests, bacteria were exposed to 0, 1562.5, 3125, 6250, 12500, 25000 µg/plate. No precipitation of the test substance was found and no bacteriotoxic effect was observed. An increased in the number of his+ revertants was not observed in the standard plate test or in the preincubation test either without S9 mix or after the addition of a metabolizing system. It was therefore concluded that the test substance is not mutagenic under these experimental conditions.