Triethoxy(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)silane

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:

1997-03-13 to 1997-03-24

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

The range of strains does not comply with the current guideline.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1997

Report date:

1997

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Version / remarks:

1983

Deviations:

yes

Remarks:

only 4 strains used

GLP compliance:

yes (incl. QA statement)

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

[2-(Perfluorohexyl)ethyl]triethoxysilane

IUPAC Name:

[2-(Perfluorohexyl)ethyl]triethoxysilane

Constituent 2

Reference substance name:

Triethoxy(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)silane

EC Number:

257-473-3

EC Name:

Triethoxy(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)silane

Cas Number:

51851-37-7

Molecular formula:

C14H19F13O3Si

IUPAC Name:

triethoxy(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)silane

Test material form:

other: liquid

Method

Species / strain

Species / strain / cell type:

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

Metabolic activation:

with and without

Metabolic activation system:

Phenobarbital and Beta-Naphthoflavone induced rat liver S9

Test concentrations with justification for top dose:

Plate incorporation (+ / - MA) 50, 160, 500, 1600, 5000 µg/plate

Pre-incubation (+ / - MA) 50, 160, 500, 1600, 5000 µg/plate

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: ethanol

- Justification for choice of solvent/vehicle: It is assumed by the reviewer that the solvent was chosen for its solubility properties and relative non-toxicity to bacteria

Controls

Controls 1

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)

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, 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:

other: 2-aminoanthracene

Remarks:

All strains (with activation)

Details on test system and experimental conditions:

ACTIVATION: One part of S9 fraction was mixed with 9 parts of a cofactor solution resulting in the following mixture: 10% S9 fraction, 22 mM KCl, 5 mM glucose-6-phosphate, 4mM NADP, 100 mM Na2HPO4/NaH2PO4 (pH 7.4), 8 mM MgCl2

APPLICATION: plate incorporation; pre-incubation

DURATION
- Preincubation period: 30 minutes at 30°C with gentle agitation
- Exposure duration: 72 hours at 37°C

NUMBER OF REPLICATIONS: triplicate plates, experiment repeated. Initial experiment used plate incorporation method, the repeat used pre-incubation.

SELECTION AGENT (mutation assays): histidine-deficient agar

DETERMINATION OF CYTOTOXICITY: condition of bacterial lawn/reduction in number of revertants

Evaluation criteria:

For a test compound to be considered positive, it must (in two independent experiments) cause at least a doubling in the mean revertants per plate of at least one tester strain. This increase must be accompanied by a dose response towards increasing concentrations of the test article.

Statistics:

For all replicate platings, the mean number of revertants per plate and the standard deviation around the mean were calculated.

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

Untreated negative controls validity:

not applicable

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

Untreated negative controls validity:

not applicable

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

Untreated negative controls validity:

not applicable

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

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Any other information on results incl. tables

Table 1: Plate incorporation test: revertants per plate (mean of three plates)

Dose/plate (µg)	TA 98		TA 100		TA 1535		TA 1537
	+ MA	- MA	+ MA	- MA	+ MA	- MA	+ MA	- MA
untreated	30	12	184	133	16	9	18	18
ethanol	28	17	160	129	9	8	25	15
50	26	15	142	157	16	10	18	16
160	26	12	167	156	16	7	20	15
500	29	16	169	132	13	6	24	13
1600	27	12	150	119	20	8	21	14
5000	35	17	175	157	14	9	20	8
positive control (2.5)	1305	110	1497	-	189	396	147	-
positive control (5)	-	-	-	621	-	-	-	-
positive control (40)	-	-	-	-	-	-	-	150

Table 2: Preincubation test: revertants per plate (mean of three plates)

Dose/plate (µg)	TA 98		TA 100		TA 1535		TA 1537
	+ MA	- MA	+ MA	- MA	+ MA	- MA	+ MA	- MA
untreated	19	16	161	165	14	12	17	19
ethanol	18	17	151	173	16	10	13	14
50	18	16	143	175	13	9	8	20
160	15	13	142	139	13	7	15	16
500	25	19	161	165	16	10	15	17
1600	18	11	161	149	14	11	13	15
5000	22	17	163	170	18	12	16	13
positive control (2.5)	1189	103	1586	-	234	440	163	-
positive control (5)	-	-	-	682	-	-	-	-
positive control (40)	-	-	-	-	-	-	-	153

Applicant's summary and conclusion

Conclusions:

Interpretation of results: negative with and without metabolic activation

[2-(Perfluorohexyl)ethyl]triethoxysilane has been tested for mutagenicity to bacteria, in a study which was conducted according to the OECD Guideline 471, compliant with GLP. The range of strains does not comply with the current guideline. No evidence of a test-substance related increase in the number of revertants was observed in Salmonella typhimurium strains TA 98, TA 100, TA 1535 or TA 1537 when tested with or without metabolic activation in the initial plate incorporation assay or the repeat preincubation experiment up to cytotoxic/limit concentrations. Appropriate positive and solvent controls were included and gave the expected results. It is concluded that the test substance is negative for mutagenicity to bacteria under the conditions of the test.