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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
Study period:
2009-08-12
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Acceptable, well-documented study report which meets basic scientific methods; not a guideline method. Method based on modification of OECD TG 471.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2009
Report date:
2009

Materials and methods

Test guideline
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
Version / remarks:
Ames II
Deviations:
yes
Remarks:
Ames II
Principles of method if other than guideline:
The test method is used to evaluate the mutagenic potential of the test substance a based on the ability to induce point mutations in selected loci of several strains of Salmonella typhimurium in a modified version of the Ames test (OECD 471), designated Ames II Assay (microtiter version), both with and without the addition of a metabolizing system (S9 mix) obtained from induced rat liver. According to the authors, this method shows a good accurancy concerning the prediction of the results in the regular Ames test.
GLP compliance:
yes
Remarks:
Sceening in GLP-certified Laboratory
Type of assay:
bacterial gene mutation assay

Test material

Constituent 1
Chemical structure
Reference substance name:
Reaction mass of ethyl (2S,3S)-3,4-dibromo-2-methylbutanoate and ethyl (2R,3R)-3,4-dibromo-2-methylbutanoate and ethyl (2S,3R)-3,4-dibromo-2-methylbutanoate and ethyl (2R,3S)-3,4-dibromo-2-methylbutanoate
EC Number:
700-225-0
Cas Number:
1160806-44-9
Molecular formula:
C7 H12 Br2 O2
IUPAC Name:
Reaction mass of ethyl (2S,3S)-3,4-dibromo-2-methylbutanoate and ethyl (2R,3R)-3,4-dibromo-2-methylbutanoate and ethyl (2S,3R)-3,4-dibromo-2-methylbutanoate and ethyl (2R,3S)-3,4-dibromo-2-methylbutanoate
Details on test material:
- Name of test material (as cited in study report): 2-Methyl-3,4-dibrombuttersäureethylester
- Physical state: liquid, colorless, clear
- Analytical purity: 98.1 wt%
- Lot/batch No.: 35684-12-5; date of production: 2009-07-14
- Storage condition of test material: refrigerator, under light exclusion
No further data.

Method

Species / strainopen allclose all
Species / strain / cell type:
S. typhimurium TA 98
Species / strain / cell type:
S. typhimurium, other: TA mix (TA 7001 - TA 7006)
Metabolic activation:
with and without
Metabolic activation system:
induced rat liver S9
Test concentrations with justification for top dose:
0, 4, 20, 100, 500, 2500, 5000 µg/ml
Vehicle / solvent:
- Vehicle(s)/solvent(s) used: DMSO
- Justification for choice of solvent/vehicle: no data
Controls
Negative solvent / vehicle controls:
yes
Positive controls:
yes
Positive control substance:
other: without S9: 4-nitrofluorene (5 µg/ml) + 2-nitrofluorene (100 µg/ml); with S9: 2-aminoanthracene (125 µg/ml)
Details on test system and experimental conditions:
METHOD OF APPLICATION: in suspension; liquid fluctuation test with and without induced rat liver S9 mix

NUMBER OF REPLICATIONS: 48 wells in triplicate plates per dose or per control

DETERMINATION OF CYTOTOXICITY
- Method: clearing of the background lawn, decrease in the number of yellow wells
Evaluation criteria:
no data
Statistics:
no data

Results and discussion

Test resultsopen allclose all
Species / strain:
S. typhimurium TA 98
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
no cytotoxicity nor precipitates, but tested up to recommended limit concentrations
Vehicle controls validity:
valid
Positive controls validity:
valid
Species / strain:
S. typhimurium, other: TA mix (TA 7001 - TA 7006)
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
no cytotoxicity nor precipitates, but tested up to recommended limit concentrations
Vehicle controls validity:
valid
Positive controls validity:
valid
Additional information on results:
MUTAGENICITY:
A relevant increase in the number of positive wells (his+ revertants) was not observed either without S9 mix or after the addition of a metabolizing system.

TEST-SPECIFIC CONFOUNDING FACTORS:
- Precipitation: No precipitation was observed.

ADDITIONAL INFORMATION ON CYTOTOXICITY:
No bacteriotoxic effect (clearing of the background lawn, decrease in the number of yellow wells) was observed up to the highest applied concentration.

For details, see attached files.
Remarks on result:
other: all strains/cell types tested
Remarks:
Migrated from field 'Test system'.

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):
negative

Under the experimental conditions chosen here, it is concluded that 2-Methyl-3,4-dibrombuttersäureethylester is not a mutagenic substance in the Ames II Assay (Salmonella typhimurium reverse mutation assay) in the absence and the presence of metabolic activation.

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