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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:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
supporting study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Published studies: screening data for a number of metal compounds, limited reporting, non-standard method

Data source

Reference
Reference Type:
publication
Title:
Rec assay mutagenicity studies on metal compounds
Author:
Kanematsu N, Hara M, & Kad T
Year:
1980
Bibliographic source:
Mutation Research, 77(2): 109-16

Materials and methods

Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
Test for reverse bacterial mutation according to Ames (1975); spot test and liquid pre-incubation assay using strains of S. typhimurium and E. coli.
GLP compliance:
no
Remarks:
: older, published study
Type of assay:
bacterial reverse mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
Sodium hexafluorosilicate; stated to be the highest purity commercially available

Method

Target gene:
Various: reversion to histidine independence
Species / strainopen allclose all
Species / strain / cell type:
S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Additional strain / cell type characteristics:
not specified
Species / strain / cell type:
S. typhimurium, other: TA 1538
Additional strain / cell type characteristics:
not specified
Species / strain / cell type:
E. coli WP2
Additional strain / cell type characteristics:
not specified
Metabolic activation:
without
Metabolic activation system:
not used
Test concentrations with justification for top dose:
Between 0.001- 10 M
Controls
Untreated negative controls:
yes
Remarks:
other metal compounds used in the screening assay gave negative results
Negative solvent / vehicle controls:
not specified
True negative controls:
not specified
Positive controls:
yes
Positive control substance:
other: other metal compounds used in the screening assay gave positive results

Results and discussion

Test resultsopen allclose all
Species / strain:
S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Metabolic activation:
without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
not specified
Vehicle controls validity:
not specified
Untreated negative controls validity:
not specified
Positive controls validity:
not specified
Species / strain:
S. typhimurium, other: TA 1538
Metabolic activation:
without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
not specified
Vehicle controls validity:
not specified
Untreated negative controls validity:
not specified
Positive controls validity:
not specified
Remarks on result:
other: all strains/cell types tested
Remarks:
Migrated from field 'Test system'.

Any other information on results incl. tables

No evidence of reverse mutation was seen under the conditions of the study. The sensitivity of the assay was confirmed by positive results with some of the compounds screened, which are known mutagens.

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):
negative without metabolic activation

No evidence of reverse mutation was seen under the conditions of the study.
Executive summary:

The mutagenicity of a number of metal compounds was investigated in bacterial screening studies. No evidence of mutagenicity was seen with sodium hexafluorosilicate (without metabolic activation) in screening assays in S. typhimurium TA98, TA100, TA1535, TA1537 and TA1538) and E. coli WP2 strains. The absence of metabolic activation is not considered to affect the integrity of the study as the substance is unlikely to be subject to biotransformation. The sensitivity of the assay is confirmed by positive responses to some known chemical mutagens also screened in this study.