Registration Dossier

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other: GLP compliant guideline study, available as unpublished report, no restrictions, fully adequate for assessment.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1997
Report Date:
1997

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:
- Substance number: 96/184
- Batch number: Vers. 130/U
- Analytical purity: 99.4%
- Appearance: liquid, colourless, clear

Method

Target gene:
his
Species / strain
Species / strain / cell type:
S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and E. coli WP2
Metabolic activation:
with and without
Metabolic activation system:
Aroclor-induced rat liver S-9 mix
Test concentrations with justification for top dose:
20 - 5000 µg/plate (standard plate tes, first test)
20 - 1500 µg/plate (standard plate tes, second test)
20 - 1500 µg/plate (preincubation test)
Vehicle / solvent:
- Vehicle used: DMSO
Controls
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
other: with metabolic activation: 2-aminoanthracene, without metabolic activation: N-methyl-N' -nitro-N-nitrosoguanidine, 4-nitro-o-phenyleridiamine, 9-aminoacridine chloride monohydrate and N-ethyl-N'-nitro-N-nitrosoguanidine
Details on test system and experimental conditions:
METHOD OF APPLICATION: standard plate test (SPT) and preincubation test (PIT)
SPT: incubation at 37°C for 48 - 72 hours in the dark
PIT: preincubation at 37°C for a duration of 20 minutes; incubation at 37°C for 48 - 72 hours in the dark

NUMBER OF REPLICATIONS: three plates per dose/control
Evaluation criteria:
In general, a substance to be characterised 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.

Results and discussion

Test results
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
Remarks:
from 1,500 μg/plate in the standard plate test and from 500 µg/plate in the preincubation assay
Vehicle controls validity:
valid
Untreated negative controls validity:
valid
Positive controls validity:
valid
Additional information on results:
No precipitation of the test substance was found.
A bacteriotoxic effect (reduced his- or trp- background growth, decrease in the number of his+ or trp+ revertants) was observed at doses from 1,500 μg/plate in the standard plate test and at doses from 500 µg/plate in the preincubation assay.
Remarks on result:
other: all strains/cell types tested
Remarks:
Migrated from field 'Test system'.

Applicant's summary and conclusion