PIGMENT ROT 5021 A

Genetic toxicity: in vitro

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

Study period:

2004-08-24 to 2004-11-15

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP compliant; Guideline Study (OECD 471)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2004

Report date:

2004

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EU Method B.13/14 (Mutagenicity - Reverse Mutation Test Using Bacteria)

Version / remarks:

of May 19, 2000

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Version / remarks:

adopted July 21, 1997

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

JAPAN: Guidelines for Screening Mutagenicity Testing Of Chemicals

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Details on test material:

- Aggregate State at Room Temperature: solid;
- Colour: red;
- Storage: room temperature;

Method

Species / strain

Species / strain 1

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Species / strain 2

Species / strain / cell type:

E. coli WP2 uvr A

Metabolic activation:

with and without

Metabolic activation system:

Phenobarbital/p-Naphthoflavone induced rat liver S9

Test concentrations with justification for top dose:

Experiment I: 3; 10; 33; 100; 333; 1000; 2500; and 5000 µg/plate;
Experiment II: 33; 100; 333; 1000; 2500; and 5000 µg/plate;

Vehicle / solvent:

DMSO

Controls

Controls 1

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: sodium azide (S. typh. TA1535, TA100); 4-nitro-o-phenylene diamine (S. typh. TA1537, TA98; methyl methanesulphonate (E. coli WP2 uvrA);

Remarks:

without metabolic activation

Controls 2

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 2-aminoanthracene (S. typh. TA1535, TA1537, TA98, TA100, E. coli WP2uvrA);

Remarks:

with metabolic activation

Details on test system and experimental conditions:

METHOD OF APPLICATION: plate incorporation (experiment I) and preincubation (experiment II)

DURATION
- Preincubation period: 60 min
- Exposure duration: 48 hours

NUMBER OF REPLICATIONS: three replicates per dose and per strain

DETERMINATION OF CYTOTOXICITY
Toxicity of the test item results in a reduction in the number of spontaneous revertants or a clearing of the bacterial background lawn.

Evaluation criteria:

A test item is considered as a mutagen if a biologically relevant increase in the number of revertants exceeding the threshold of twice (strains TA 98, TA 100, and WP2 uvrA) or thrice (strains TA 1535 and TA 1537) the colony count of the corresponding solvent control is observed.

A dose dependent increase is considered biologically relevant if the threshold is exceeded at more than one concentration.

An increase exceeding the threshold at only one concentration is judged as biologically relevant if reproduced in an independent second experiment.
A dose dependent increase in the number of revertant colonies below the threshold is regarded as an indication of a mutagenic potential if reproduced in an independent second experiment. However, whenever the colony counts remain within the historical range of negative and solvent controls such an increase is not considered biologically relevant.

Statistics:

No statistical evaluation of the data is required.

Results and discussion

Test results

Test results 1

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:

cytotoxicity

Remarks:

in TA 1535 and TA 1537 (-S9) and in strain TA 100 (+/- S9)

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 2

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity nor precipitates, but tested up to recommended limit concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

TEST-SPECIFIC CONFOUNDING FACTORS
- Precipitation: Occurred in experiment I at concentrations of 333 µg/plate and higher and in experiment II at concentrations of 1000 µg/plate and higher in all test strains with and without S9.

COMPARISON WITH HISTORICAL CONTROL DATA:

ADDITIONAL INFORMATION ON CYTOTOXICITY:
Minor toxic effects, evident as a reduction in the number of revertants, occurred in experiment I in strains TA 1535 and TA 1537 at 2500 µg/plate with metabolic activation and in strain TA 100 at 5000 µg/plate with and without metabolic activation.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative