Registration Dossier

Toxicological information

Genetic toxicity: in vitro

Currently viewing:

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:
September 3 2002 - September 30 2002
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Study conducted in accordance with generally accepted scientific principles, possibly with incomplete reporting or methodological deficiencies, which do not affect the quality of the relevant results.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2002
Report Date:
2002

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
JAPAN: Guidelines for Screening Mutagenicity Testing Of Chemicals
Deviations:
no
GLP compliance:
yes
Type of assay:
bacterial reverse mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent

Method

Target gene:
Histadine for Salmonella
Tryptophan for E. coli
Species / strainopen allclose all
Species / strain / cell type:
S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Details on mammalian cell type (if applicable):
Not applicable
Additional strain / cell type characteristics:
not specified
Species / strain / cell type:
E. coli WP2 uvr A
Details on mammalian cell type (if applicable):
Not applicable
Additional strain / cell type characteristics:
not specified
Metabolic activation:
with and without
Metabolic activation system:
S9, post-mitochondrial supernatant of rat-liver homogenate. 5,6-Benzoflavone and phenobarbital were used as an inducer of drug-metabolizing enzyme system.
Test concentrations with justification for top dose:
156, 313, 625, 1250, 2500 and 5000 micro gramper plate.

The mutagenicity was assayed from a maximum level of 5000 micro gram test substance/plate.
Vehicle / solvent:
- Vehicle(s)/solvent(s) used: Anhydrous DMSO

- Justification for choice of solvent/vehicle: Not recorded
Controlsopen allclose all
Untreated negative controls:
no
Negative solvent / vehicle controls:
yes
Remarks:
Dimethylsulfoxide
True negative controls:
no
Positive controls:
yes
Positive control substance:
other: 2-(2-Furyl)-3-(5-nitoro-2-furyl)acrylamide (AF-2)
Remarks:
99.0 wt% Purity
Positive controls:
yes
Positive control substance:
sodium azide
Remarks:
99.9 wt% Purity
Positive controls:
yes
Positive control substance:
9-aminoacridine
Remarks:
97.0 wt% Purity
Positive controls:
yes
Positive control substance:
other: 2-Aminoanthracene (2-AA)
Remarks:
96.7 wt% Purity
Details on test system and experimental conditions:
METHOD OF APPLICATION:
in agar (plate incorporation)

DURATION
- Preincubation period:
20 minutes at 37 deg C

- Exposure duration:
48 hours

- Expression time:
48 hours and 20 minutes

- Selection time (if incubation with a selection agent):
48 hours and 20 minutes preincubation.

- Fixation time (start of exposure up to fixation or harvest of cells):
Not applicable


NUMBER OF REPLICATIONS:
2 x 2 experiments

NUMBER OF CELLS EVALUATED:
Not recorded.
Evaluation criteria:
A compound is regarded as mutagenetic when it induced the revertant colonies dose-dependently and the number of revertants is more than twice the control.
Statistics:
None recorded

Results and discussion

Test resultsopen allclose all
Species / strain:
S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Metabolic activation:
with and without
Genotoxicity:
negative
Remarks:
Diethylaminotriethoxysilane did not increase revertant colonies up to 5000 micro gram/plate with or withpout metabolic activation.
Cytotoxicity / choice of top concentrations:
not specified
Vehicle controls validity:
not specified
Untreated negative controls validity:
not specified
Positive controls validity:
valid
Species / strain:
E. coli WP2 uvr A
Metabolic activation:
with and without
Genotoxicity:
negative
Remarks:
Diethylaminotriethoxysilane did not increase revertant colonies up to 5000 micro gram/plate with or withpout metabolic activation.
Cytotoxicity / choice of top concentrations:
not specified
Vehicle controls validity:
not specified
Untreated negative controls validity:
not specified
Positive controls validity:
valid
Additional information on results:
TEST-SPECIFIC CONFOUNDING FACTORS
- Effects of pH: Not recorded

- Effects of osmolality: Not recorded

- Evaporation from medium: Not recorded

- Water solubility: The substance decomposed with water. This did not affect the study data.

- Precipitation: Not recorded

- Other confounding effects: None recorded.

RANGE-FINDING/SCREENING STUDIES:
Please see Attachment 1.

COMPARISON WITH HISTORICAL CONTROL DATA:
None recorded.


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

Any other information on results incl. tables

Please see attachment 2 for full table of results.

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):
negative Diethylaminotriethoxysilane did not increase revertant colonies up to 5000 micro gram/plate with or withpout metabolic activation.

The test material was considered to be non-mutagenic under the conditions of this test.
Executive summary:

In a reverse gene mutation assay in bacteria TA1535, TA1537, TA98 and TA100 strains of S. typhimurium and WP2 uvr A strain of  E. coli were exposed to Diethylaminotriethoxysilane at concentrations of  156, 313, 625, 1250, 2500 and 5000  micro g/plate in the presence and absence of rat liver homogenate metabolising system (0.1 ml liver S9 in 1ml S9 with standard co-factors). 

Diethylaminotriethoxysilane was tested up to the maximum recommended dose level of 5000 micro g/plate.

The positive controls induced the appropriate responses in the corresponding strains.  There was no recorded evidence of induced mutant colonies over background.

This study is classified as acceptable.  This study satisfies the requirement for Test Guideline: : Guidelines for Screening Mutagenicity Testing Of Chemicals for in vitromutagenicity (bacterial reverse gene mutation) data.

Diethylaminotriethoxysilane was considered to be non-mutagenic under the conditions of this test.