N-[3-(trimethoxysilyl)propyl-1,3-Benzenedimethanamine

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:

12/08/1997 to 02/10/1997

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

The study was conducted according to a protocol that is similar to the appropriate OECD test guideline, with acceptable restrictions. The restrictions were that only duplicate plates were used.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1997

Report date:

1997

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

other: "Standards for Mutagenicity Tests using Microorganisms" (Notification No. 77, Ministry of Labour, Japan, September 1, 1988

Test guideline 2

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

Only duplicate plates tested

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

439-510-7

EC Name:

-

Cas Number:

149048-48-6

Molecular formula:

Constituent 1: C14H26N2O3Si Constituent 2: C13H22N2O2Si

IUPAC Name:

1-(3-{13-[3-(aminomethyl)phenyl]-6,6,8,8-tetramethoxy-7-oxa-2,12-diaza-6,8-disilatridecan-1-yl}phenyl)methanamine; 1-[3-({[3-(trimethoxysilyl)propyl]amino}methyl)phenyl]methanamine

Test material form:

liquid

Method

Target gene:

Histidine (Salmonella strains) and tryptophan (E. coli strain)

Base-pair substitution type: Salmonella typhimurium TA100, TA1535, and Escherichia coli WP2 uvrA.
Frame-shift type: Salmonella typhimurium TA98, TA1537.

Species / strain

Species / strain 1

Species / strain / cell type:

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

Additional strain / cell type characteristics:

not applicable

Species / strain 2

Species / strain / cell type:

E. coli WP2 uvr A

Additional strain / cell type characteristics:

not applicable

Metabolic activation:

with and without

Metabolic activation system:

phenobarbital and 5,6-benzoflavene induced rat

Test concentrations with justification for top dose:

1.2, 4.9, 20, 78, 313, 1250 and 5000 µg/plate

Vehicle / solvent:

Test substance
- Vehicle(s)/solvent(s) used: DMSO.
- Justification for choice of solvent/vehicle: None given.

Positive controls
- AF-2, ICR-191, 2AA and B[a]P: DMSO.
- sodium azide: distilled water.

Controls

Controls 1

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 2-(2-furyl)-3-(5-nitro-2-furyl)acrylamide (AF-2)

Remarks:

-MA: TA 100, WP2 uvrA - 0.01 µg/plate; TA 98 - 0.1 µg/plate

Controls 2

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

sodium azide

Remarks:

-MA: TA 1535 - 0.5 µg/plate

Controls 3

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 2-Methoxy-6-chloro-9-[3-(2-chloroethyl)aminopropylamino]acridine·2HCl (ICR-191)

Remarks:

-MA: TA 1537 - 1.0 µg/plate

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:

+MA: TA 1535 - 2.0 µg/plate; WP2 uvrA - 10.0 µg/plate

Controls 5

Untreated negative controls:

yes

Negative solvent / vehicle controls:

no

True negative controls:

yes

Positive controls:

no

Positive control substance:

benzo(a)pyrene

Remarks:

+MA: TA 100, TA 98, TA 1537 - 5.0 µg/plate

Details on test system and experimental conditions:

ACTIVATION:
Composition of S9 mix (per 1 ml):
Water: 0.9 mL
S9: 0.1 mL
MgCl2: 8.0 µmol
KCl: 33.0 µmol
G-6-P: 5.0 µmol
NADPH: 4.0 µmol
NADH: 4.0 µmol
Na-phosphate buffer (pH 7.4): 100.0 µmol

METHOD OF APPLICATION: preincubation

DURATION
- Preincubation period: 20 minutes at 37°C
- Exposure duration: 48 hours at 37°C

SELECTION AGENT (mutation assays): minimal glucose agar

NUMBER OF REPLICATIONS: duplicate plates. An initial dose range-finding study was followed by two further independent experiments.

DETERMINATION OF CYTOTOXICITY: reduction in number of revertant colonies

Evaluation criteria:

If the number of revertant colonies on the test plates increased significantly in comparison with that on the control plates (based on twice as many as that of the negative control), and dose-response and reproducibility were also observed, the test substance was judged to be positive.

Statistics:

No statistical analysis done.

Results and discussion

Test results

Key result

Species / strain:

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

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Additional information on results:

RANGE-FINDING STUDY: Growth inhibition was determined for seven concentrations of test substance: 1.2, 4.9, 20, 78, 313, 1250 and 5000 µg/plate.

Growth inhibition was observed as follows:
≥4.9 µg/plate for TA1537 without S9.
≥20 µg/plate for TA100, TA1535 and TA98 without S9.
≥78 µg/plate for E.coli WP2 uvrA without metabolic activation.

Hence, the highest concentrations of test substance used in the main test were as follows:

S. typhimurium TA1537 without S9: 4.9 µg/plate.
S. typhimurium TA100, TA1535, TA98 without S9: 20 µg/plate.
E. coli WP2 uvrA without S9: 78g µg/plate.
All S. typhimurium strains with S9: 313 µg/plate.
E. coli WP2 uvrA with S9: 1250 µg/plate.

Remarks on result:

other: all strains/cell types tested

Applicant's summary and conclusion

Conclusions:

The submission substance has been tested for mutagenicity to bacteria in a study conducted according to a protocol that is similar to OECD 471. No evidence for a test substance induced increase in the number of revertants was observed when tested up to cytotoxic concentrations with and without metabolic activation in S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and E. coli WP2 using the preincubation method in the initial and the repeat experiment. Appropriate positive and solvent controls were included and gave expected results. It is concluded that the test substance is negative for mutagenicity under the conditions of the test.