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Toxicological information

Genetic toxicity: in vitro

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Administrative data

Endpoint:
in vitro gene mutation study in bacteria
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions

Data source

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

Materials and methods

Test guideline
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
Principles of method if other than guideline:
In an Ames test MACROLEX Rotviolett R was using Salmonella typhimurium LT2 mutants TA 1535, TA 100, TA 1537, TA 98 and TA 102.
GLP compliance:
not specified
Type of assay:
bacterial reverse mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent

Method

Species / strain
Species / strain / cell type:
S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA 102
Details on mammalian cell type (if applicable):
Histidine deficient mutants - riginal strains were obtained from Prof. Bruce ames
Metabolic activation:
with and without
Metabolic activation system:
S9 mix
Test concentrations with justification for top dose:
0, 16, 50, 158, 500, 1581 or 5000 µg/plate
0, 16, 50, 158, 500, 1581 or 5000 µg/tube
Vehicle / solvent:
DMSO (dimethylsulphoxide)
Controls
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
True negative controls:
not specified
Positive controls:
yes
Positive control substance:
sodium azide
cumene hydroperoxide
other: 4-nitro-1,2-phenylene diamine, 2-aminoanthracene
Details on test system and experimental conditions:
MACROLEX Rotviolett R was initially screened with one plate per dose using the Salmonella/microsome plate incorporation test for point mutagenic effects in doses of up to and including 5000 µg per plate on five Salmonella typhimurium LT2
mutants. These comprised the histidine-auxotrophic strains TA 1535, TA 100, TA 1537, TA 98 and TA 102.
Additionally MACROLEX Rotviolett R was screened in an independent repeat using the Salmonella/microsome test for point mutagenic effects in doses up to 5000 µg per tube after preincubation for 20 minutes at 37°C. All other conditions remained unchanged.
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, A 100 and TA 98 this increase should be about twice that of negative controls, whereas for A 1537, at
least a threefold increase should be reached. For TA 102 an increase of about 150 mutants should be reached. Otherwise, the result is evaluated as negative. However, these guidelines may be overruled by good scientific judgement.

Results and discussion

Test results
Key result
Species / strain:
S. typhimurium, other: TA 98, TA 100, TA 102, TA 1535, TA 1537
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
other: Plate incorporation test: Doses up to and including 500 µg per plate did not cause any bacteriotoxic effects. Preincubation test: Doses up to and including 1581µg per tube did not cause any bacteriotoxic effects.
Vehicle controls validity:
valid
Untreated negative controls validity:
valid
Positive controls validity:
valid
Additional information on results:
Evidence of mutagenic activity of MACROLEX Rotviolett R was not seen. No biologically relevant increase in the mutant count, in comparison with the negative controls, was observed.

Applicant's summary and conclusion

Conclusions:
Negative
Executive summary:

In an Ames test MACROLEX Rotviolett R was using Salmonella typhimurium LT2 mutants TA 1535, TA 100, TA 1537, TA 98 and TA 102. MACROLEX Rotviolett R was negative (non-mutagenic) without and with S9 mix in the plate incorporation as well as in the preincubation modification of the Salmonella/microsome test.