Dichloromethyl(3,3,3-trifluoropropyl)silane

Genetic toxicity: in vitro

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

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

The study was conducted similar to an appropriate OECD test guideline, with acceptable restrictions and predates GLP . The restrictions were that the test did not include an additional strain to detect cross-linking mutagens. In view of the lack of genetic toxicity demonstrated in studies on mammalian cells, and the absence of structural features that indicate that such mutagenicity is likely, testing in an appropriate 5th strain is not considered necessary. In addition, the only silicon-containing substance which has given a positive result in a bacterial strain capable of detecting cross-linking or oxidising mutagens contains an epoxy- side-chain (which is associated with cross-linking mutagenicity), and this substance was positive in Salmonella typhimurium strains TA 100, TA 1535 as well as in E.coli WP2uvrA

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1979

Report date:

1979

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Version / remarks:

(adopted 1997)

Deviations:

yes

Remarks:

(the test did not include an additional strain to detect cross-linking mutagens; only 4 concentrations instead of 5 stated in the guideline were tested)

GLP compliance:

no

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Dichloromethyl(3,3,3-trifluoropropyl)silane

EC Number:

211-623-4

EC Name:

Dichloromethyl(3,3,3-trifluoropropyl)silane

Cas Number:

675-62-7

Molecular formula:

C4H7Cl2F3Si

IUPAC Name:

(dichloromethyl)(3,3,3-trifluoropropyl)silane

Details on test material:

- Name of test material (as cited in study report): Dichloromethyl (3,3,3-trifluoropropyl)silane
- Substance type: Chlorosilane

Method

Target gene:

his-operon

Species / strain

Species / strain 1

Species / strain / cell type:

S. typhimurium TA 1538

Species / strain 2

Species / strain / cell type:

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

Metabolic activation:

with and without

Metabolic activation system:

Aroclor 1254 induced rat liver

Test concentrations with justification for top dose:

0.5, 5, 100, or 500 μl/plate

Vehicle / solvent:

The solvent (negative control) for all treament/strains was deionised water, absolute ethanol or dimethylsulfoxide (DMSO).

Controls

Controls 1

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: -S9: TA100 and TA1535 (Sodium azide 100 µg/plate), TA1537 (9-Aminoacridine 100 µg/plate) and TA 1538 (2-Nitrofluorene 100 µg/plate).

Controls 2

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 2-Anthramine (Anth) +S9: All strains = 100 µg/plate. -S9: TA 98 and TA1538 =100 µg/plate.

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Exposure duration: 48 hours

NUMBER OF REPLICATIONS: 3

Evaluation criteria:

Strains TA 1535, TA 1537 and TA 1538:
If the solvent control value is within the normal range, a chemical that produces a positive dose response over three concentrations with the lowest increase equal to twice the solvent control value is considered to be mutagenic.
Strains TA 98 and TA 100:
If the solvent control value is within the normal range, a chemical that produces a positive dose response over three concentrations with the highest increase equal to twice the solvent control for TA 100 and two to three times solvent control value for strain TA 98 is considered to be mutagenic. For these strains, the dose response increase should start at approximately the solvent control values.
Reproducibility: If a chemical produces a response in a single test that cannot be reproduced in one or more additional runs, the initial positive test data loses significance.

Statistics:

Not reported

Results and discussion

Test results

Test results 1

Species / strain:

S. typhimurium TA 1538

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Test results 2

Species / strain:

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

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Additional information on results:

Not reported

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

Table 1: Overlay plate test results

Test	Revertants per plate
	TA 1535	TA 1537	TA 1538	TA 98	TA 100
Non-activation
Solvent control	23	5	38	20	176
Postive control*	173	61	294	154	>10^3
Test material (µl)
0.5	22	3	40	23	142
5	21	6	38	20	160
100	28	4	40	21	164
500	20	4	32	22	114
Activation
Solvent control	24	7	36	26	181
Postive control**	263	97	>10^3	>10^3	>10^3
Test material (µl)
0.5	22	6	45	26	191
5	26	4	39	26	197
100	23	4	41	29	183
500	22	3	30	24	156
* TA-1535	AZ 100 µg/plate		** TA-1535	ANTH 100 µg/plate
*TA-1537	AZ 100 µg/plate		**TA-1537	ANTH 100 µg/plate
*TA-1538	NF 100 µg/plate		**TA-1538	ANTH 100 µg/plate
*TA98	NF 100 µg/plate		**TA98	ANTH 100 µg/plate
*TA100	AZ 100 µg/plate		**TA100	ANTH 100 µg/plate
Solvent	DMSO 50 µl/plate		Solvent	DMSO 50 µl/plate

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative with and without metabolic activation

The test item was tested for bacterial mutagenicity (Ames Test) similar to the OECD TG 471 and predates GLP. The Salmonella typhimurium strains TA 1535, TA 1537, TA 1538, TA 98, and TA 100 were exposed to the test material both in absence and presence of a metabolic activation system. An additional strain for the detection of cross-linking agents was not included into the test. No treatment related increase in the number of revertants was observed in any of the tester strains. Appropriate solvent and positive controls were included into the test and gave the expected results. Hence, the test item was considered to be non-mutagenic to bacteria under the conditions of the test.