Dibromopyranthrene-8,16-dione

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Remarks:

Ames test

Type of information:

other: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Study period:

1991

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

The test was conducted by means of Read Across approach. Further information was attached at section 13

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1991

Report date:

1991

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

GLP compliance:

not specified

Remarks:

screening assay

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Vat Orange 002 - Similar Substance 01

IUPAC Name:

Vat Orange 002 - Similar Substance 01

Test material form:

solid: particulate/powder

Method

Target gene:

histidine

Species / strain

Species / strain / cell type:

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

Metabolic activation:

with and without

Metabolic activation system:

S-9 fraction (rat liver homogenate)

Test concentrations with justification for top dose:

First assay: 20, 100, 500, 2500 and 5000 µg/plate all strains
Second assay: 50, 100, 200, 400, 600 µg/plate - TA98

Vehicle / solvent:

DMSO

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

True negative controls:

yes

Positive controls:

yes

Positive control substance:

9-aminoacridine

other: 2-aminoanthracene, N-methyl-N'-nitro-N-nitroso-guanidine, 4-nitro-o-phenylenediamine

Details on test system and experimental conditions:

To 2 mL of molten top agar in a sterile test-tube, were added 0.1 mL of the tester strain culture, graded quantities of the test substance in 0.1 mL solution and, for the S-9 series, 0.5 mL of S-9 Mix. The contents of the test-tube were rapidly mixed and poured onto the surface of previously prepared minimal agar plates with Vogel-Bonner E mixture. The plate were incubated upside down at 37°C for 2 days, after which the number of revertants colonies appearing was counted.

Evaluation criteria:

Doubling of the spontaneous mutation rate (control)

Results and discussion

Test results

Key result

Species / strain:

other: Salmonella typhimurium TA98, TA100, TA1535, and TA1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity, but tested up to precipitating concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

Positive and negative controls were valid

Applicant's summary and conclusion

Conclusions:

Not mutagenic

Executive summary:

A study was conducted to determine the mutagenic potential of the test substance according to OECD Guideline 471. Four strains of Salmonella typhimurium (TA98, TA100, TA1535 and TA1537) were exposed to the test substance at concentrations of 20 to 5000 µg/plate with or without metabolic activation (S-9 Mix) for 48 h. Negative and positive controls were valid. The test substance with and without metabolic activation did not induce mutagenic activity in bacteria. Under the study conditions, the test substance was considered to be not mutagenic.