Decyltrimethoxysilane

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

The genotoxicity in bacteria of the test substance was assessed during a study performed according to the pre-incubation method and therefore similar to the OECD Testing Guideline 471. Strains S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and E. coli WP2 were used. A dose-range finding study was performed in order to determine the doses to be used in the final test. Negative and positive controls were valid. No reproducible increase in the number of revertant colonies were observed in presence of the test substance compared with the solvent control group with and without metabolic activation. It can be concluded that the substance was not mutagenic under the conditions of the test.

 

In accordance with Annex VII of REACH it is not required to perform in vitro genotoxicity testing in mammalian cells or in vivo genotoxicity testing.

Link to relevant study records

Reference

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 29 September 1987 to 09 October 1987

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Version / remarks:

Preincubation method

Deviations:

no

GLP compliance:

no

Type of assay:

bacterial reverse mutation assay

Target gene:

Histidine (S. typhimurium). Tryptophan (E. coli).

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and E. coli WP2

Metabolic activation:

with and without

Metabolic activation system:

S9-mix

Test concentrations with justification for top dose:

A dose finding test was performed.
Final test was performed at 157, 313, 625, 1,250, 2,500, and 5,000 µg/plate with and without metabolic activation for strains TA1535 and WP2.
Final test was performed at 2, 3, 7, 13, 25, 50 and 100 µg/plate with and without metabolic activation for strains TA100, TA98, and TA1537.

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: DMSO
- Justification for choice of solvent/vehicle: Standard solvent.

Negative solvent / vehicle controls:

yes

Positive controls:

yes

Positive control substance:

4-nitroquinoline-N-oxide

9-aminoacridine

N-ethyl-N-nitro-N-nitrosoguanidine

benzo(a)pyrene

other: 2-Aminoanthracene

Details on test system and experimental conditions:

DURATION
- Preincubation period: 10 hours
- Exposure duration: 48 hours

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Conclusions:

The test substance is non-mutagenic under the conditions of the test with and without metabolic activation.

Executive summary:

The genotoxicity in bacteria of the test substance was assessed during a study performed according to the pre-incubation method and therefore similar to the OECD Testing Guideline 471.

Strains S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and E. coli WP2 were used.

A dose-range finding study was performed in order to determine the doses to be used in the final test.

Each bacterium was inoculated in a test tube containing nutrient broth and incubated for 10h at 37°C. Test solution, buffer solution, and bacterium suspension were introduced in a test tube with or without S9-mix and shaken for 20 min in a water bath at 37°C. Agar was added to the mixture and uniformly overlaid on a minimal glucose agar plate. Each plate was incubated for 48h at 37°C and then the number of revertant colonies were colonies.

Negative and positive controls were valid.

No reproducible increase in the number of revertant colonies were observed in presence of the test substance compared with the solvent control group with and without metabolic activation. It can be concluded that the substance was not mutagenic under the conditions of the test.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Justification for classification or non-classification

An in vitro gene mutation study in bacteria was performed on Decyltrimethoxysilane in accordance with a method similar to the OECD Testing Guideline 471. Results were negative with and without metabolic activation. The substance does not meet the criteria for classification according to Regulation (EC) No.1272/2008.