Tris(2-methoxyethoxy)vinylsilane

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1999-07-09 to 1999-10-16

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1999

Report date:

1999

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Tris(2-methoxyethoxy)vinylsilane

EC Number:

213-934-0

EC Name:

Tris(2-methoxyethoxy)vinylsilane

Cas Number:

1067-53-4

Molecular formula:

C11H24O6Si

IUPAC Name:

ethenyl-tris(2-methoxyethoxy)silane

Method

Species / strain

Species / strain 1

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Species / strain 2

Species / strain / cell type:

E. coli WP2 uvr A

Metabolic activation:

with and without

Metabolic activation system:

Aroclor induced rat liver S9

Test concentrations with justification for top dose:

100, 333, 1000, 3333, and 5000 µg/plate

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: DMSO
- Justification for choice of solvent/vehicle: Stability in solvent

Controls

Controls 1

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 2-aminoanthracene

Remarks:

all strains with activation

Controls 2

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

sodium azide

Remarks:

TA 100 and TA 1535 without activation

Controls 3

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

9-aminoacridine

Remarks:

TA 1537 without activation

Controls 4

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

methylmethanesulfonate

Remarks:

E. coli WP2 uvrA without activation

Controls 5

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

2-nitrofluorene

Remarks:

TA 98 without activation

Details on test system and experimental conditions:

METABOLIC ACTIVATION
0.5 ml of S9 mix containing 10% Aroclor induced rat liver S9 with NADP as cofactor. The S9 was assayed for ability to metabolize 2-aminoanthracene and 7,12-dimethylbenz(a)anthracene to forms mutagenic to S. typhimurium TA100

METHOD OF APPLICATION: in agar (plate incorporation); preincubation

DURATION
- Preincubation period: 60 minutes
- Exposure duration: 48-72 hours
- Expression time (cells in growth medium): 48-72 hours
- Fixation time (start of exposure up to fixation or harvest of cells): 48-72 hours

SELECTION AGENT (mutation assays): not specified

NUMBER OF REPLICATIONS: concentrations were plated in triplicate, experiment was repeated

NUMBER OF CELLS EVALUATED: 0.3 x 10E09 cells per ml

DETERMINATION OF CYTOTOXICITY
- Method: other: condition of bacterial lawn

OTHER EXAMINATIONS:
- Determination of polyploidy:
- Determination of endoreplication:

OTHER: The study was performed in two phases, using the preincubation and plate incorporation methodology. The first phase, the preliminary toxicity study, was used to establish the dose range for the mutagenicity assay. The second phase, the mutagenicity assay (initial and independent repeat assays), was used to evaluate the mutagenic potential of the test article.

Evaluation criteria:

A substance is considered positive if it causes a dose-related increase in the mean revertants per plate of at least one tester strain with a minimum of two increasing concnetrations of test substance, of greater than two times (TA 98, 100 and E. coli) or 3 times (TA 1535 and 1537) the vehicle control value.

Statistics:

No statistical evaluation carried out.

Results and discussion

Test results

Test results 1

Key result

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity nor precipitates, but tested up to recommended limit concentrations

Vehicle controls validity:

valid

Positive controls validity:

valid

Test results 2

Key result

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity nor precipitates, but tested up to recommended limit concentrations

Vehicle controls validity:

valid

Positive controls validity:

valid

Test results 3

Key result

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity nor precipitates, but tested up to recommended limit concentrations

Vehicle controls validity:

valid

Positive controls validity:

valid

Test results 4

Key result

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity nor precipitates, but tested up to recommended limit concentrations

Vehicle controls validity:

valid

Positive controls validity:

valid

Test results 5

Key result

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity nor precipitates, but tested up to recommended limit concentrations

Vehicle controls validity:

valid

Positive controls validity:

valid

Any other information on results incl. tables

Preliminary Toxicity Test: Ten dose levels, ranging from 6.7 to 5000 ug/plate were tested with the four Salmonella strains and WP2 uvrA in the presence or absence of S9.  Neither precipitate nor appreciable toxicity was observed. 

No positive responses were observed in the mutagenicity assays. Neither precipitate nor appreciable toxicity was observed. All bacterial strains exhibited mutagenic responses to the positive control substances, indicating that the tests were sensitive and valid.

Table 1: Preincubation experiment 1: Number of revertants per plate (mean of 3 plates)  

Concentration µg/plate	Strain    TA 98		Strain    TA 100		Strain    TA 1535		Strain    TA 1537		E. coli WP2 uvrA
	- MA	+ MA	- MA	+ MA	- MA	+ MA	- MA	+ MA	- MA	+ MA
0*	16	21	137	134	10	9	8	8	12	17
100	12	18	146	122	11	14	5	6	15	16
333	11	16	141	154	9	10	7	7	15	15
1000	13	17	141	161	9	8	6	6	16	15
3333	12	11	134	159	12	7	6	6	16	16
5000	12	15	135	147	9	7	7	5	19	17
Positive control	745	416	700	611	420	100	229	78	371	173

* Solvent control with DMSO

Table 2: Preincubation experiment 2: Number of revertants per plate (mean of 3 plates)

Concentration µg/plate	Strain    TA 98		Strain    TA 100		Strain    TA 1535		Strain    TA 1537		E. coli WP2 uvrA
	- MA	+ MA	- MA	+ MA	- MA	+ MA	- MA	+ MA	- MA	+ MA
0*	14	16	104	131	13	12	9	9	12	15
100	14	15	112	136	10	13	10	9	15	12
333	13	17	127	143	13	12	9	9	16	13
1000	14	16	108	147	13	11	6	8	13	14
3333	11	14	111	123	11	12	6	9	15	14
5000	12	17	109	153	13	13	5	7	12	14
Positive control	480	400	620	617	294	68	51	68	282	91

* Solvent control with DMSO

Applicant's summary and conclusion

Conclusions:

In an in vitro gene mutation study in bacteria, conducted accordig to OECD test guideline 471 and in compliance with GLP, tris(2-methoxyethoxy)vinylsilane has been tested using S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and E. coli WP2 uvrA. No increase in the number of revertants was observed in any strain with or without metabolic activation, neither in the preliminary plate incorporation range-finding study nor in the initial and repeat preincubation assays. The substance was tested to limit concentrations and appropriate solvent and positive controls were included and gave expected results. It is concluded that the test substance is negative for mutagenicity to bacteria under the conditions of the test.