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Toxicological information

Genetic toxicity: in vitro

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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
Study period:
06 August 2013 to 23 August 2013
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP compliant, guideline study, available as an unpublished report.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2013
Report Date:
2013

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
Deviations:
not specified
Principles of method if other than guideline:
Potassium dicyanoaurate was tested for mutation (and toxicity) in three histidine-requiring starins of Salmonella typhimurium (TA98, TA100 and TA102) using a plate incorporation treatment methodology, in the absence and presence of S-9.
GLP compliance:
not specified
Type of assay:
bacterial reverse mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: particulate/powder
Remarks:
migrated information: powder
Details on test material:
- Name of test material: Potassium dicyanoaurate
- Substance type: White powder
- Physical state: Solid
- Stability under test conditions: Stable for the duration of the study.
- Storage condition of test material: Room temperature, protected fro light, in a tightly closed container.

Method

Target gene:
histidine
Species / strainopen allclose all
Species / strain / cell type:
S. typhimurium TA 98
Details on mammalian cell type (if applicable):
Not applicable
Additional strain / cell type characteristics:
not applicable
Species / strain / cell type:
S. typhimurium TA 100
Details on mammalian cell type (if applicable):
Not applicable
Additional strain / cell type characteristics:
not applicable
Species / strain / cell type:
S. typhimurium TA 102
Details on mammalian cell type (if applicable):
Not applicable
Additional strain / cell type characteristics:
not applicable
Metabolic activation:
with and without
Metabolic activation system:
rat liver metabolising system (S-9)
Test concentrations with justification for top dose:
Experiment 1: 5, 15.81, 50, 158.1, 500, 1581 and 5000 μg/plate.

Experiment 2: 0.03906, 0.1563, 0.625, 2.5, 10 and 40 μg/plate.
Vehicle / solvent:
- Vehicle(s)/solvent(s) used: purified water
- Justification for choice of solvent/vehicle: The test article was completely soluble in the aqueous assay system at all concentrations tested.
Controlsopen allclose all
Untreated negative controls:
yes
Remarks:
TA98
Negative solvent / vehicle controls:
yes
Remarks:
purified water
True negative controls:
no
Positive controls:
yes
Positive control substance:
2-nitrofluorene
Remarks:
without S-9
Untreated negative controls:
yes
Remarks:
TA98
Negative solvent / vehicle controls:
yes
Remarks:
purified water
True negative controls:
no
Positive controls:
yes
Positive control substance:
benzo(a)pyrene
Remarks:
with S-9
Untreated negative controls:
yes
Remarks:
TA100
Negative solvent / vehicle controls:
yes
Remarks:
purified water
True negative controls:
no
Positive controls:
yes
Positive control substance:
sodium azide
Remarks:
without S-9
Untreated negative controls:
yes
Remarks:
TA100
Negative solvent / vehicle controls:
yes
Remarks:
purified water
True negative controls:
no
Positive controls:
yes
Positive control substance:
other: 2-aminoanthracene
Remarks:
with S-9
Untreated negative controls:
yes
Remarks:
TA102
Negative solvent / vehicle controls:
yes
Remarks:
purified water
True negative controls:
no
Positive controls:
yes
Positive control substance:
mitomycin C
Remarks:
without S-9
Untreated negative controls:
yes
Remarks:
TA102
Negative solvent / vehicle controls:
yes
Remarks:
purified water
True negative controls:
no
Positive controls:
yes
Positive control substance:
other: 2-aminoanthracene
Remarks:
with S-9
Details on test system and experimental conditions:
METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Preincubation period: no
- Exposure duration: not reported
- Expression time (cells in growth medium): not applicable
- Selection time (if incubation with a selection agent): not applicable

NUMBER OF REPLICATIONS: triplicate plates. Negative control were included in quintuplicate and positive controls in triplicate.

DETERMINATION OF CYTOTOXICITY
- Method: plates were assessed for numbers of revertant colonies and examined for effects on the growth of the bacterial background lawn.
Statistics:
Standard deviation

Results and discussion

Test resultsopen allclose all
Species / strain:
S. typhimurium TA 98
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
cytotoxicity
Vehicle controls validity:
valid
Untreated negative controls validity:
valid
Positive controls validity:
valid
Species / strain:
S. typhimurium TA 100
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
cytotoxicity
Vehicle controls validity:
valid
Untreated negative controls validity:
valid
Positive controls validity:
valid
Species / strain:
S. typhimurium TA 102
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
cytotoxicity
Vehicle controls validity:
valid
Untreated negative controls validity:
valid
Positive controls validity:
valid
Additional information on results:
TEST-SPECIFIC CONFOUNDING FACTORS
- Water solubility: The test article was completely soluble in the aqueous assay system at all concentrations tested.

Remarks on result:
other: all strains/cell types tested
Remarks:
Migrated from field 'Test system'.

Any other information on results incl. tables

Toxicity

Following Mutation Experiment 1 treatments of all the test strains, evidence of toxicity, in the form of a complete killing of the test bacteria was observed at 15.81 μg/plate and above in strains TA98 and TA100 in the absence and presence of S-9 and at 158.1 μg/plate and above in strain TA102 in the absence and presence of S-9. In addition, a marked reduction in revertant numbers was observed at 5 μg/plate in strains TA98 and TA100 in the absence of S-9 and at 50 μg/plate in strain TA102 in the absence and presence of S-9.

Following Mutation Experiment 2 treatments of all the test strains, evidence of toxicity, ranging from a slight thinning of the background bacterial lawn and/or a marked reduction in revertant numbers to complete killing of the test bacteria, was observed at 2.5 μg/plate and above in strains TA98 and TA100 in the absence and presence of S-9 and at 10 or 40 μg/plate and above in strain TA102 in the absence and presence of S-9 respectively.

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):
negative

The test item, potassium dicyanoaurate, was considered to be non-mutagenic under the conditions of the test.
Executive summary:

Objective

The objective of the study was to evaluate the potential mutagenic activity of Potassium dicyanoaurate by examining its ability to revert three histidine-requiring strains of Salmonella typhimurium in the absence and presence of a rat liver metabolising system (S-9).

Method

Potassium dicyanoaurate was tested for mutation (and toxicity) using a plate incorporation treatment methodology, in the absence and presence of S-9. Appropriate negative (vehicle) and positive controls were included.

Conclusion

It was concluded that Potassium dicyanoaurate did not induce mutation in three histidine-requiring strains (TA98, TA100, and TA102) of Salmonella typhimurium when tested under the conditions of this study. These conditions included treatments up to toxic concentrations in the absence and in the presence of a rat liver metabolic activation system (S-9).