diethylmethoxyborane

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: GLP-guideline study, but restriction due to missing of the E.coli-strain

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1996

Report date:

1996

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

425-380-9

EC Name:

-

Cas Number:

7397-46-8

Molecular formula:

C5H13BO

IUPAC Name:

methyl diethylborinate

Details on test material:

- Name of test material (as cited in study report): DEMB
- Physical state: Water-white liquid
- Analytical purity: 99.4%
- Lot/batch No.: 183
- Expiration date of the lot/batch: August 01, 1997
- Storage condition of test material: At room temperature in the dark

Method

Target gene:

Histidine-mutation

Species / strain

Species / strain / cell type:

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

Additional strain / cell type characteristics:

other: Additional mutations: rfa:deep rough (defective lipopolysaccharide cellcoat); gal: mutation in the galactose metabolism; chl: mutation in nitrate reductase bio defective biotin synthesis: uvrB: loss of the excision repair system

Metabolic activation:

with and without

Metabolic activation system:

S9-mix

Test concentrations with justification for top dose:

with and without S9-mix:
1. experiment: 3, 10, 33, 100, 333, 1000, 3330, 5000 ug/plate
2. experiment: 100, 333, 1000, 3330, 5000 ug/plate

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: methanol
- Justification for choice of solvent/vehicle: Because DEMB is a highly flammable liquid, it was treated with special care. Directly after weighing, the test substance was dissolved in methanol.

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

Positive controls:

yes

Positive control substance:

other: without metabolic activation: sodium azide, 9-aminoacridine, daunomycine, methylmethanesulfonate; with metabolic activation: 2-aminoanthracene (2AA)

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation); preincubation

DURATION
- Exposure duration: 48 hours

NUMBER OF REPLICATIONS: triplicate

DETERMINATION OF CYTOTOXICITY
- Method: bacterial backgroud lawn

Evaluation criteria:

A test substance is considered negative (not mutagenic) in the test if:
a) The total number of revertants in any tester strain at any concentration is not greater than two times the solvent control value, with or without metabolic activation.
b) The negative response should be reproducible in at least one independently repeated experiment.

A test substance is considered positive (mutagenic) in the test if:
a) lt induces at least a 2-fold, dose related increase in the number of revertants with respect to the number induced by the solvent control in any of the tester strains, either with or without metabolic activation.
However, any mean plate count of less than 20 is considered to be not significant.
b) The positive response should be reproducible in at least one independently repeated experiment.

Results and discussion

Test results

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:

other: Toxicity occurred at concentrations of 3330 ug/plate and higher

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

TEST-SPECIFIC CONFOUNDING FACTORS
- Precipitation: DEMB did not precipitate.

RANGE-FINDING/SCREENING STUDIES: DEMB was tested in strain TA100 with concentrations of 3, 10, 33, 100, 333, 1000, 3330 and 5000 ug/plate in the absence and presence of S9-mix.

COMPARISON WITH HISTORICAL CONTROL DATA: The negative and strain-specific positive control values were within the laboratory background historical control data ranges indicating that the test conditions were adequate and that the metabolic activation system functioned properly.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.