1-(4-methyl-2-nitrophenylazo)-2-naphthol

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:

1992

Reliability:

2 (reliable with restrictions)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1992

Report date:

1992

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

1-(4-methyl-2-nitrophenylazo)-2-naphthol

EC Number:

219-372-2

EC Name:

1-(4-methyl-2-nitrophenylazo)-2-naphthol

Cas Number:

2425-85-6

Molecular formula:

C17H13N3O3

IUPAC Name:

1-(4-methyl-2-nitrophenylazo)-2-naphthol

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

Purity > 99%

Method

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:

Hamster S9-mix

Test concentrations with justification for top dose:

7 different doses from 100 microgram/plate to 7 500 microgram/plate

Results and discussion

Test results

Key result

Species / strain:

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

Metabolic activation:

with and without

Genotoxicity:

positive

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

other: strain/cell type: TA 1537

Remarks:

Migrated from field 'Test system'.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative with metabolic activation

Summarizing, it can be stated that C.I Pigment Red 3 is not mutagenic in the standard plate test (Ames Test) but in the preincubation method to Prival.

Executive summary:

C.I Pigment Red 3 was tested for mutagenicity with the strains TA 100, TA 1535, TA 1537 and TA 98 of Salmonella typhimurium.

The mutagenicity studies were conducted in the standard plate test (Ames Test) and in a modified preincubation test (Prival Test). The studies were performed in the absence and in the presence of a metabolizing system derived from hamster liver homogenate. A dose range of 6 different doses from 4 microgram/plate to 5 000 microgram/plate was used for the mutagenicity study. In a third independent experiment a dose range of 7 different doses from 100 microgram/plate to 7 500 microgram/plate was used.

 

Control plates without mutagen showed that the number of spontaneous revertant colonies was similar to that described in the 1iterature. All the positive control compounds gave the expected increase in the number of revertant colonies.

 

Toxicity: The test compound proved to be not toxic to the bacterial strains. 5 000 microgram/plate was chosen as top dose level for the mutagenicity study.

 

a) Ames Test: Mutagenicity: In the absence of the metabolic activation system the test com- pound did not show a dose dependent increase in the number of revertants in any of the bacterial strains.

 

b) Prival Test: In the presence of hamster liver S-9 using the preincubation method according to Prival C.I Pigment Red 3 induce a dose dependent increase in the number of revertant colonies, with the tester strain TA 1537.

 

Summarizing, it can be stated that C.I Pigment Red 3 is not mutagenic in the standard plate test (Ames Test) but in the preincubation method to Prival.