(3-chloropropyl)triethoxysilane

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:

2002-04-03 to 2002-05-10

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2002

Report date:

2002

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EU Method B.13/14 (Mutagenicity - Reverse Mutation Test Using Bacteria)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Version / remarks:

1997

Deviations:

no

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

(3-chloropropyl)triethoxysilane

EC Number:

225-805-6

EC Name:

(3-chloropropyl)triethoxysilane

Cas Number:

5089-70-3

Molecular formula:

C9H21ClO3Si

IUPAC Name:

(3-chloropropyl)triethoxysilane

Method

Target gene:

histidine

Species / strain

Species / strain / cell type:

S. typhimurium, other: TA 1535, TA 1537, TA 98, TA 100 and TA 102

Metabolic activation:

with and without

Metabolic activation system:

Aroclor induced rat liver S9

Test concentrations with justification for top dose:

100-5000 µg/plate

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: ethanol
- Justification for choice of solvent/vehicle: none given in report

Controls

Controls 1

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 metabolic activation

Controls 2

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 metabolic 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 metabolic activation

Controls 4

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

methylmethanesulfonate

Remarks:

TA 102 without metabolic activation

Controls 5

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 2-anthracene amide

Remarks:

TA 98, TA 102, TA 1537 with metabolic activation

Controls 6

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

cyclophosphamide

Remarks:

TA 100, TA 1535 with metabloic activation

Details on test system and experimental conditions:

METHOD OF APPLICATION: in medium; in agar (plate incorporation); preincubation;
DURATION
- Preincubation period: 60 minutes
- Exposure duration: 48 hours
- Expression time (cells in growth medium): 48 hours
- Fixation time (start of exposure up to fixation or harvest of cells): 48 hours

NUMBER OF REPLICATIONS: 3 plates per concentration and 2 independent experiments

NUMBER OF CELLS EVALUATED:

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

Evaluation criteria:

A response is considered positive if there is a statistically significant dose-related increase in the number of revertants relative to the solvent control, by at least 2-fold (TA 98, 100 and 102) or 3-fold (TA 1535 or 1537), and that this is reproducible and revertants are confirmed by streaking to histidine-free agar plates.

Statistics:

Mann and Whitney U-test and Spearman's rank correlation coefficient.

Results and discussion

Test results

Test results 1

Key result

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

Preincubation method: 316 µg/plate -S9; 3160 µg/plate +S9

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Test results 2

Key result

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

Preincubation method: 5000 µg/plate -S9

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Test results 3

Key result

Species / strain:

S. typhimurium TA 102

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

Preincubation method: 1000 µg/plate - S9 and +S9

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Test results 4

Key result

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

Plate incorporation method: 5000 µg/plate -S9; 316 µg/plate + S9 Preincubation method: 316 µg/plate -S9; 3160 µg/plate +S9

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Test results 5

Key result

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

Pre-incubation method: 316 µg/plate -S9; 1000 µg/plate +S9

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 average number of revertants per plate (mean of 3 plates)

 

Concentration (µg/plate)	TA 98		TA 100		TA 102		TA 1535		TA 1537
	-MA	+MA	-MA	+MA	-MA	+MA	-MA	+MA	-MA	+MA
5000	35.3	34.3	179.7	157.3	150.7	151.7	0.0*	0.0*	4.0*	3.7*
3160	31.7	26.3	134.0	137.3	172.3	120	39.7*	0.0*	2.7*	5.7*
1000	40.3	19.0	122.7	128.0	161.7	155.7	22.7	0.0*	5.0	5.3*
316	32.0	27.3	121.3	166.0	172.3	202	28.0	1.3	2.7	5.3
100	46.7	28.3	109.3	159.7	197.3	240.7	22.7	37.7	4.7	4.3
Negative control 100 µL/plate	32.0	36	119.0	153.0	220.7	292.0	16.3	27.7	5.3	3.7
Positive control	817.0	333	447.3	491.7	1231.0	905.7	957.3	841.3	290.3	290.7

 * = scarce background lawn

Table 2 Preincubation test average number of revertants per plate (mean of 3 plates)

Concentration (µg/plate)	TA 98		TA 100		TA 102		TA 1535		TA 1537
	-MA	+MA	-MA	+MA	-MA	+MA	-MA	+MA	-MA	+MA
5000	0.0*	0.0*	31.0*	72.7*	1.3*	0.0*	0.0*	0.0*	0.0*	0.0*
3160	10.3*	0.0*	65.3*	80.3*	0.0*	0.0*	0.0*	7.0*	0.0*	2.3*
1000	10.7*	50.0*	93.0*	116.3*	74.3*	0.0*	0.0*	18.7*	0.0*	0.0*
316	12.3	25.7	119.7	135	280	340.7	3.3	20.7	3	13.3
100	19.7	29.7	102.3	132.3	275.3	370.7	11	17.3	3.7	12.3
Negative control 100 µl/plate	32.3	35	119.7	126	246.7	364.7	12	18.7	6.3	14.7
Positive control	303.3	313	464	477	1131	1153.7	891	984.3	286.3	288.7

* = scarce background lawn

Applicant's summary and conclusion

Conclusions:

(3-chloropropyl)triethoxysilane has been tested in a valid and reliable study according to OECD Test Guideline 471 and in compliance with GLP. No increase in the number of revertants was observed in any strain with or without activation in either the initial plate incorporation assay or the subsequent preincubation assay. The solvent and positive controls gave the expected results. It is concluded that the substance is negative for mutagenicity to bacteria under the conditions of the test.