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Toxicological information

Genetic toxicity: in vitro

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Administrative data

Endpoint:
in vitro gene mutation study in mammalian cells
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:
2012
Report Date:
2013

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 476 (In Vitro Mammalian Cell Gene Mutation Test)
Principles of method if other than guideline:
The study was performed to investigate the potential of C.I. Direct Blue 264 to induce gene mutations at the HPRT locus in V79 cells of the Chinese hamster. The assay was performed in two independent experiments, using two parallel cultures each. The first main experiment was performed with and without liver microsomal activation and a treatment period of 4 hours. The second experiment was performed with a treatment time of 4 hours with and 24 hours without metabolic activation.
GLP compliance:
yes
Type of assay:
mammalian cell gene mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
not specified
Details on test material:
Identity: C.I. Direct Blue 264

Method

Target gene:
HPRT locus in V79 cells
Species / strain
Species / strain / cell type:
Chinese hamster lung fibroblasts (V79)
Metabolic activation:
with and without
Metabolic activation system:
S9 mix
Test concentrations with justification for top dose:
Experiment I
Exposure period: 4 hours (with and without S9 mix)
Concentrations without S9 mix: 125, 250, 500, 750 and 1000(p) µg/mL
Concentrations with S9 mix: 15.6, 31.3, 62.5(p), 125(p) and 250(p) µg/mL

Experiment II
Exposure period: 4 hours (with and without S9 mix)
Concentrations without S9 mix: 3.9, 7.8, 15.6 and 31 µg/mL
Concentrations with S9 mix: 15.6, 31.3, 62.5(p), 125(p) and 250(p) µg/mL

p = precipitation visible to the unaided eye
Vehicle / solvent:
DMSO
Controls
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
True negative controls:
yes
Positive controls:
yes
Positive control substance:
7,12-dimethylbenzanthracene
ethylmethanesulphonate

Results and discussion

Test results
Species / strain:
Chinese hamster lung fibroblasts (V79)
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
cytotoxicity
Vehicle controls validity:
valid
Untreated negative controls validity:
valid
Positive controls validity:
valid
Remarks on result:
other: all strains/cell types tested
Remarks:
Migrated from field 'Test system'.

Any other information on results incl. tables

The study was performed to investigate the potential of C.I. Direct Blue 264 to induce gene mutations at the HPRT locus in V79 cells of the Chinese hamster.

The assay was performed in two independent experiments, using two parallel cultures each. The first main experiment was performed with and without liver microsomal activation (S9 mix) and a treatment period of 4 hours. The second experiment was performed with a treatment time of 4 hours with and 24 hours without metabolic activation.

The highest concentration of the pre-experiment (2000 μg/mL) was limited by the solubility properties of C.I. Direct Blue 264 in DMSO and aqueous medium. The maximum concentration of the main experiments was limited by cytotoxic effects and precipitation of the test item.

No substantial and reproducible dose dependent increase of the mutation frequency was observed in both main experiments.

Appropriate reference mutagens, used as positive controls, induced a distinct increase in mutant colonies and thus, showed the sensitivity of the test system and the activity of the metabolic activation system.

In conclusion it can be stated that under the experimental conditions reported C.I. Direct Blue 264 did not induce gene mutations at the HPRT locus in V79 cells. Therefore, C.I. Direct Blue 264 is considered to be non-mutagenic in this HPRT assay.

 

Applicant's summary and conclusion

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

The study was performed to investigate the potential of C.I. Direct Blue 264 to induce gene mutations at the HPRT locus in V79 cells of the Chinese hamster.

The assay was performed in two independent experiments, using two parallel cultures each. The first main experiment was performed with and without liver microsomal activation (S9 mix) and a treatment period of 4 hours. The second experiment was performed with a treatment time of 4 hours with and 24 hours without metabolic activation.

The highest concentration of the pre-experiment (2000 μg/mL) was limited by the solubility properties of C.I. Direct Blue 264 in DMSO and aqueous medium. The maximum concentration of the main experiments was limited by cytotoxic effects and precipitation of the test item.

No substantial and reproducible dose dependent increase of the mutation frequency was observed in both main experiments.

Appropriate reference mutagens, used as positive controls, induced a distinct increase in mutant colonies and thus, showed the sensitivity of the test system and the activity of the metabolic activation system.

In conclusion it can be stated that under the experimental conditions reported C.I. Direct Blue 264 did not induce gene mutations at the HPRT locus in V79 cells. Therefore, C.I. Direct Blue 264 is considered to be non-mutagenic in this HPRT assay.