Ethers, C5-6-branched alkyl Me

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Remarks:

Type of genotoxicity: gene mutation

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP-compliant guideline study, no restrictions, fully adequate for assessment.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1991

Report date:

1991

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:

2-methoxy-2-methylbutane

EC Number:

213-611-4

EC Name:

2-methoxy-2-methylbutane

Cas Number:

994-05-8

Molecular formula:

C6H14O

IUPAC Name:

1,1-dimethylpropyl methyl ether

Details on test material:

- Name of test material (as cited in study report): TAME
- Physical state: clear aqueous liquid
- Analytical purity: 98.4%
- Purity test date: 23 April 1990
- Lot/batch No.: 25.-30.11.89 sample nr: 500763
- Expiration date of the lot/batch: 24 nov 1992
- Storage condition of test material: refrigirator

Method

Target gene:

his

Species / strain

Species / strain / cell type:

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

Metabolic activation:

with and without

Metabolic activation system:

S9 (from liver homogenate from aroclor 1254 pretreated SD rats)

Test concentrations with justification for top dose:

0, 8, 40, 200, 1000, 2000 and 5000 ug/plate

Vehicle / solvent:

methanol (not tested as negative control only, from literature it is known that methanol is negative)

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

no

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: sodium azide, nitrofurantoin, 4-nitro-1,2-phenylene diamine, 2-aminoanthracene

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Preincubation period: none
- Exposure duration: 2 days at 37 degree centigrade

A toxicity pre-test, an initial and a repeat test were performed.

Evaluation criteria:

A reproducible and dose-related increase in mutant counts of at least one strain is considered to be a positive result. For TA 1535, 100 and 98, this increase should be about twice the amount of the negative controls, whereas for TA 1537, at least a threefold increase should be reached.

Statistics:

After completion of scoring, mean of revertant colonies and standard deviation for each dose are determined.

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: weak strain-specific bacteriotoxic effect from 200 µg/plate

Vehicle controls validity:

not applicable

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

Doses up to and including 40 μg did not cause toxicity. At higher doses, TAME had a weak strain-specific bacteriotoxic effect. Nevertheless all the doses could be used for assessment. No indications of mutagenic effects were seen at doses up to 5,000 g/plate, with or without metabolic activation with male Sprague-Dawley liver S9 fraction.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.