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Toxicological information

Genetic toxicity: in vitro

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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
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1998
Report Date:
1998

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
Qualifier:
according to
Guideline:
OECD Guideline 472 (Genetic Toxicology: Escherichia coli, Reverse Mutation Assay)
GLP compliance:
yes
Type of assay:
bacterial reverse mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
Name of test substance: MGDN
Batch No.: Gre 3038/F 535
Date of manufacture: September 9 - 11, 1994
Test substance No.: 96/83
Degree of purity: 97.9%
Appearance of consistency: White powder
Storage: Room temperature

Method

Target gene:
His (Salmonella);
Trp (E. coli)
Species / strainopen allclose all
Species / strain / cell type:
S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Details on mammalian cell type (if applicable):
All strains have a defective excision repair System (uvrB), which prevents the repair of lesions which are induced in the DNA, and this deficiency results in greatly enhanced sensitivity of some mutagens. Furthermore, all strains show a considerably reduced hydrophilic polysaccharide layer (rfa), which leads to an increase in permeability to lipophilic substances.
The strains TA 1535 and TA 100 are derived from histidine-prototrophic Salmonella strains by the substitution mutation his G 46 and are used to detect base pair substitutions. TA 1537 and TA 98 are strains for the detection of frameshift mutagens.
Species / strain / cell type:
E. coli WP2 uvr A
Details on mammalian cell type (if applicable):
Escherichia coli WP2 uvrA is a derivative of E. coli WP2 with a deficient excision repair and is used to detect substances which induce base pair
substitutions.
Metabolic activation:
with and without
Metabolic activation system:
S9-mix
Test concentrations with justification for top dose:
Experiment 1: 0; 20; 100; 500; 2500 and 5000 µg/plate.
Experiment 2: 0; 20; 100; 500; 2500 and 5000 µg/plate.
Vehicle / solvent:
- Vehicle(s)/solvent(s) used: [DMSO]
- Justification for choice of solvent/vehicle: The test substance was soluble in DMSO
Controls
Untreated negative controls:
other: sterility control
Negative solvent / vehicle controls:
yes
True negative controls:
not specified
Positive controls:
yes
Positive control substance:
other: 2-aminoanthracene, N-methyl-N´-nitro-N-nitrosoguanidine, 4-nitro-o-phenylendiamine, 9-aminoacridine, N-ethyl-N'-nitro-N-nitrosoguanidin
Details on test system and experimental conditions:
Positive controls:
with S-9 mix: 2.5 µg 2-aminoanthracene (2-AA) (dissolved in DMSO) for the strains TA 100, TA 98, TA 1537 and TA 1535
60 µg 2-AA (dissolved in DMSO) for the strain E. coli WP2 uvrA
without S-9 mix: 5 µg N-methyl-N`-nitro-N-nitrosoguanidine (MNNG) (dissolved in DMSO) for the strains TA 100 and TA 1535
10 µg 4-nitro-o-phenylendiamine(NOPD, dissolved in DMSO) for the strain TA 98
100 µg 9-aminoacridine (AAC) chloride monohydrate (dissolved in DMSO) for the strain TA 1537
10 µg N-ethyl-N'-nitro-N-nitrosoguanidin (ENNG, dissolved in DMSO) for the strain E. coli WP2 uvrA

Experiment 1: Standard plate test.
Experiment 2: Preincubation test.
Evaluation criteria:
In general, a substance to be characterized as positive in the bacterial tests has to fulfill the following requirements:
- doubling of the spontaneous mutation rate (control)
- dose-response relationship
- reproducibility of the results.
Statistics:
no data

Results and discussion

Test resultsopen allclose all
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: Occasionally a slight decrease in the number of revertants was observed.
Vehicle controls validity:
valid
Untreated negative controls validity:
not specified
Positive controls validity:
valid
Species / strain:
E. coli WP2 uvr A
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
other: Occasionally a slight decrease in the number of revertants was observed.
Vehicle controls validity:
valid
Untreated negative controls validity:
not specified
Positive controls validity:
valid
Additional information on results:
No test substance precipitation was found.
Remarks on result:
other: all strains/cell types tested
Remarks:
Migrated from field 'Test system'.

Applicant's summary and conclusion