Registration Dossier

Diss Factsheets

Administrative data

Endpoint:
in vitro gene mutation study in bacteria
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2004-04-8 to 2004-06-28
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2004
Report date:
2004

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
JAPAN: Guidelines for Screening Mutagenicity Testing Of Chemicals
Version / remarks:
2003-11-13
GLP compliance:
yes
Type of assay:
bacterial reverse mutation assay

Test material

Constituent 1
Chemical structure
Reference substance name:
-
EC Number:
442-650-1
EC Name:
-
Cas Number:
56450-90-9
Molecular formula:
F4Mg5Na2O20Si8
IUPAC Name:
silanedione hydrofluoride magnesium dihydride sodium hydride
Test material form:
solid: particulate/powder
Details on test material:
One sample of Sodium Magnesium Fluoride Silicate, Lot No. 91107
EINECS# 442-650-1
CAS# 56450-90-9
Sample submission date: 16.11.2009
Specific details on test material used for the study:
SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: Topy Indsutries Ltd. / 040430
- Expiration date of the lot/batch: does not expire

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: 19.6 to 25.7 °C under dehumified conditions in a container
- Stability under test conditions: stable
- Solubility and stability of the test substance in the solvent/vehicle: soluble and stable
- Reactivity of the test substance with the solvent/vehicle of the cell culture medium: no

Method

Species / strainopen allclose all
Species / strain / cell type:
S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Species / strain / cell type:
E. coli WP2 uvr A
Metabolic activation:
with and without
Metabolic activation system:
S9 mix
Test concentrations with justification for top dose:
5000, 2500, 1250, 625, 312.5 and 156.3 µg/plate for TA98 in the presence of S9 mix.
1250, 625, 312.5 and 156.3 µg/plate for TA1537 in the presence of S0 mix.
5000, 2500, 1250, 625 and 312.5 µg/plate for all bacterial strains in the absence of S9 mix and for TA100, TA1535, and WP2uvrA in the presence of S9 mix.

The top dose of 5000 µg/plate was the dose in the dose-finding test.
Vehicle / solvent:
- Vehicle(s)/solvent(s) used: CMSO
- Justification for choice of solvent/vehicle: good solubility of test substance, negative genetic toxicity
Controls
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
True negative controls:
yes
Positive controls:
yes
Positive control substance:
sodium azide
other: 2-(2-Furyl)-3-(5-nitro-2-furyl)acrylamide, 9-Aminoacridine h
Details on test system and experimental conditions:
METHOD OF APPLICATION: in medium; in agar (plate incorporation)

DURATION
- Preincubation period: 20 min
- Exposure duration: 48 h
- Expression time (cells in growth medium): 48 h

NUMBER OF REPLICATIONS: 2

METHODS OF SLIDE PREPARATION AND STAINING TECHNIQUE USED: After incubation, the presence or absence of precipiates on the plates was observed macroscopically. As a result, it was found to be difficult to count the number of revertant colonies with a colony analyzer, since the shape of the precipitates on the plates treated with magnesium sodium fluoride silicate was similar to that of colonies. Therefore, the number of revertant colonies on the plates treated with the negative control substance and the number of revertant colonies on the plates treated with magnesium sodium fluoride silicate were counted by hand with a handy colony counter.
The number of revertant colonies on the plates treated with positive control substances was counted with a colony analyzer. Then presence or absence or absence of batierial growth inhibition was examined using a microscope at 100-fold magnification.

Rationale for test conditions:
Guideline
Evaluation criteria:
The number of revertant colonies on the plates treated with magnesium sodium fluoride silicate was less than twice the number of colonies on the plates treated witgh the negative control substance for all baterial strains in the absence and presence of S9 mix.
Statistics:
The mean number of revertant colonies was calculated for each concentration. Statistical analysis was not perforemd since results were evaluated following the evaluation criteria described.

Results and discussion

Test resultsopen allclose all
Key result
Species / strain:
S. typhimurium TA 1537
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
Key result
Species / strain:
S. typhimurium TA 98
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
Key result
Species / strain:
E. coli WP2 uvr A
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
Key result
Species / strain:
S. typhimurium TA 1535
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
Key result
Species / strain:
S. typhimurium 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

Applicant's summary and conclusion

Conclusions:
Magnesium sodium fluoride silicate has no mutagenic potential under the conditions of the study.
Executive summary:

The genetic toxicity potential of magnesium sodium fluoride silicate was examined in a guideline study similar to OECD 471 (Ames test). Magnesium sodium fluoride silicate has no mutagenic potential under the conditions of the study.