Registration Dossier

Toxicological information

Genetic toxicity: in vitro

Currently viewing:

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: guideline study and GLP

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2012
Report Date:
2012

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
GLP compliance:
yes
Type of assay:
bacterial reverse mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: particulate/powder
Remarks:
migrated information: powder
Details on test material:
black powder
content 80.7 %

Method

Species / strain
Species / strain / cell type:
S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA 102
Additional strain / cell type characteristics:
other: S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA 102
Metabolic activation:
with and without
Metabolic activation system:
S9-mix was made from the livers of at least 5 adult male Sprague-Dawley rats . For enzyme induction the animals received a single intraperitoneal injection of Aroclor 1254 dissolved in corn oil five days prior to sacrifice
Test concentrations with justification for top dose:
with and without S9-mix:
50, 160, 500, 1600, 5000 µg/plate
Vehicle / solvent:
deionized water
Controls
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
True negative controls:
not specified
Positive controls:
yes
Positive control substance:
2-nitrofluorene
sodium azide
cumene hydroperoxide
mitomycin C
other: 4-nitro-1,2-phenylend diamine; 2-aminoanthracene
Details on test system and experimental conditions:
2 independent trials :
according to preincubation methodology or according to plate incorporation methodology
Evaluation criteria:
A reproducible and dose-related increase in mutant counts of at least one strain is considered to be a positive result. For TA1535, TA100, TA1537, TA98 this increase should be about twice that of negative controls. For TA102 an increase of about 100 mutants should be reached.
Otherwise the result is evaluated as negative
Statistics:
no data

Results and discussion

Test results
Species / strain:
S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA 102
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
no cytotoxicity
Vehicle controls validity:
valid
Untreated negative controls validity:
valid
Positive controls validity:
valid
Remarks on result:
other: other: S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA 102
Remarks:
Migrated from field 'Test system'.

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):
negative
Executive summary:

Nigrosin was initially investigated in the Ames test according to OECD TG 471 and GLP using the Salmonella typhimurium TA 98, TA100, TA102, TA1535, TA1537 and concentrations up to and including 5000 µg/plate.Bacteriotoxicity was not reached. None of the 5 strains used showed a dose-related and biologically relevant increase in mutant counts over those of the negative controls neither in the presence nor in the absence of the metabolic activation system S9 -mix. The positve controls were functional.

Due to these results Nigrosin WLF has to be regarded as non-mutagenic in the Ames test .