Trisodium bis[3-hydroxy-4-[(2-hydroxy-1-naphthyl)azo]-7-nitronaphthalene-1-sulphonato(3-)]chromate(3-)

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1991

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

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 (incl. QA statement)

Type of assay:

bacterial gene mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Trisodium bis[3-hydroxy-4-[(2-hydroxy-1-naphthyl)azo]-7-nitronaphthalene-1-sulphonato(3-)]chromate(3-)

EC Number:

260-906-9

EC Name:

Trisodium bis[3-hydroxy-4-[(2-hydroxy-1-naphthyl)azo]-7-nitronaphthalene-1-sulphonato(3-)]chromate(3-)

Cas Number:

57693-14-8

Molecular formula:

C40H20CrN6O14S2.3Na

IUPAC Name:

trisodium bis[3-hydroxy-4-[(2-hydroxy-1-naphthyl)azo]-7-nitronaphthalene-1-sulphonato(3-)]chromate(3-)

Test material form:

solid: particulate/powder

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:

Rat liver S9 mix

Test concentrations with justification for top dose:

0-8-40-20-1000-5000 µg/plate + 5 different positive control
Repeat: 0-125-250-500-1000-2000-4000 µg/plate

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: water

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

Positive controls:

yes

Positive control substance:

sodium azide

other: nitro furatoin (TA 100); 4-nitro-1,2-phenylenediamine(TA 1537, TA98); 2- aminoanthracene

Details on test system and experimental conditions:

DURATION
- Exposure duration: 48 h

NUMBER OF REPLICATIONS: 4

DETERMINATION OF CYTOTOXICITY
- Method: background lawn density

Evaluation criteria:

Reproducible and dose-related increase of mutant count in at least one strain is considered a positive result.

Results and discussion

Test results

Test results 1

Species / strain:

E. coli WP2

Remarks:

not tested according to the OECD guideline 471 in force at the time the test was run.

Metabolic activation:

with and without

Genotoxicity:

not determined

Cytotoxicity / choice of top concentrations:

not determined

Test results 2

Species / strain:

S. typhimurium TA 1535

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

Test results 3

Species / strain:

S. typhimurium TA 100

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

Test results 4

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

ambiguous

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 5

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

ambiguous

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Any other information on results incl. tables

Summary of mean values without S9 mix

dose (µg/plate)	TA1535	TA100	TA1537	TA 98
0 8 40 200 1000 5000 Na N3 NF 4 -NPDA	15 15 13 14 13 P 537	110  117 118 112 125 P 243	12  11 14 17 32 P 45	28  34 38 50 68 P 65
0 125 250 500 1000 2000 4000 Na N3 NF 4 -NPDA	12 10 10 14 7 11 P 747	102 92 98 108 115 109 P 460	9 19 17 19 30 23 P 74	32 37 37 38 46 43 P 129
0 400 600 800 1000 1200 1400 1600 4 -NPDA			6 22 20 24 34 32 31 21 83	33 52 56 56 66 65 59 62 291

Summary of mean values with S9-mix

dose (µg/plate)	TA 1535	TA100	TA 1537	TA 98
30 % S9mix 0 8 40 200 1000 5000 2 -AA	22 29 25 23 18 P 152	159 165 182 172 192 P 663	15 11 14 15 23 P 75	34 46 38 57 85 P 464
10 % S9mix 0 125 250 500 1000 2000 4000 2 -AA	15 17 14 15 15 11 P 253	126 145 153 124 109 107 P 934	13 14 13 18 23 22 P 443	36 54 55 53 50 42 P 1304
30 % S9mix 0 400 600 800 1000 1200 1400 1600 2 -AA			13 12 14 15 26 22 18 24 116	52 71 83 83 87 83 82 65 586

Applicant's summary and conclusion

Conclusions:

Test substance showed equivocal mutagenic effects in 2 of 4 strains in Salmonella typhimurim.

Executive summary:

Method

The test material was examined in four strains of Salmonella typhimurium for gene mutations in bacteria (Ames test) in the presence and absence of a metabolic activation system (rat liver S9 mix). The strains employed were TA 98, TA 100, TA 1535, and TA 1537. All concentrations were tested in four plates each. The dose range was 0 (vehicle), 8 to 5000 µg/plate and several positive controls.

Results

Positive as well as negative controls gave the expected results. Plates treated with test item showed precipitation at concentrations of 4000 µg/plate and above. Cytotoxicity was noted at doses above 800 µg/plate. Equivocal mutagenic effects were observed in TA 1537 and TA 98. There were weak increases of revertant colonies, less than three times, mostly less than twice, the negative controls. However, no clear dose response relations could be determined, even when the dose was increased significantly.