4,6-diphenyl-1,3,5-triazin-2(1H)-one

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:

19 Feb - 28 Jun 1993

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: GLP guideline study. Lack of a second positive control substance in the assays with metabolic activation.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1993

Report date:

1993

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

, 2-aminoanthracene was used as sole positive control in assays with metabolic activation in TA98, 100, 1537, and 102.

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

2-Hydroxy-4,6-diphenyl-1,3,5-triazin

IUPAC Name:

2-Hydroxy-4,6-diphenyl-1,3,5-triazin

Details on test material:

- Name of test material (as cited in study report): 2-Hydroxy-4,6-diphenyl-1,3,5-triazin; (FAT 92376/A)
- Analytical purity: 98%
- Lot/batch No.: 10.26
- Expiration date of the lot/batch: December 1996

Method

Target gene:

HIS

Species / strain

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA 102

Metabolic activation:

with and without

Metabolic activation system:

Aroclor 1254 induced rat liver S9 Mix

Test concentrations with justification for top dose:

Range finding test in TA100 (+/- metabolic activation):
20 µg/plate
61 µg/plate
185 µg/plate
555 µg/plate
1666 µg/plate
5000 µg/plate

Main test in TA98, TA100, TA1535, TA1537, TA102 (+/- metabolic activation):
61 µg/plate
185 µg/plate
555 µg/plate
1666 µg/plate
5000 µg/plate

Vehicle / solvent:

Dimethylsulfoxid (DMSO)

Controls

Untreated negative controls:

not specified

Negative solvent / vehicle controls:

yes

True negative controls:

not specified

Positive controls:

yes

Positive control substance:

other: Without S9: 2-nitrofluorene, sodium azide, mitomycin C, 9-aminoacridine-HCl*H2O; with S9: 2-aminoanthracene, cyclophosphamide

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Exposure duration: 48 h

NUMBER OF REPLICATIONS: Three plates per concentration.

DETERMINATION OF CYTOTOXICITY
- Method:
A toxicity test (check for reduction in the number of revertant colonies) was carried out with strain TA 100 without and with microsomal activation at six concentrations of the test substance and one negative control.

Positive controls: One positive control is run per strain.
Without activation:
TA 98: 2-nitrofluorene, in DMSO, 2 to 20 µg/plate
TA 100 and TA 1535: sodium azide, in bidistilled water 2 to 20 µg/plate
TA 102: mitomycin C, in bidistilled water, 0.2 to 10 µg/plate
TA 1537: 9-aminoacridine-HCl*H2O, in DMSO 50 to 300 µg/plate
With activation:
TA 98, TA 100 and TA 1537: 2-aminoanthracene, in DMSO 1 to 10 µg/plate
TA 102: 2-aminoanthracene, in DMSO, 5 to 100 µg/plate
TA 1535: cylophosphamide, in bidistilled water, 100 to 600 µg/plate

Evaluation criteria:

Assay acceptance criteria:
A test is considered acceptable if the mean colony counts of the control values of all strains are within the acceptable ranges and if the results of the positive controls meet the criteria for a positive response. In either case the final decision is based on the scientific judgement of the Study Director.

Criteria for a positive response:
At least a reproducible meaningful increase of the mean number of revertants per plate above that of the negative control at any concentration for one or more of the following strains: S. typhimurium TA 98, TA 100, TA 102, TA 1535 and TA 1537.
Generally a concentration-related effect should be demonstrable.

Statistics:

No statistics used.

Results and discussion

Test results

Species / strain:

S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA 102

Metabolic activation:

with and without

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

5000 µg/plate, TA 100, without metabolic activation (range finding assay): slight reduction of revertants; 5000 µg/plate, TA 102, with and without metabolic activation (main experiment): slight reduction of revertants

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Additional information on results:

TEST-SPECIFIC CONFOUNDING FACTORS
- Precipitation:
Precipitates were observed in the plates with 555, 1666, and 5000 µg/plate

RANGE-FINDING/SCREENING STUDIES:
No increase in revertant colonies was observed.

COMPARISON WITH HISTORICAL CONTROL DATA:
Arithmetic Mean and Standard Deviation of colony counts obtained in 68 separate experiments over the period of January 01, 1992 to December 31, 1992 were provided. The results obtained in this study were within the given limits of the historical control data.

INFORMATION ON CYTOTOXICITY:
5000 µg/plate, TA 100, without metabolic activation (range finding assay): slight reduction of revertants
5000 µg/plate, TA 102, with and without metabolic activation (Main experiment): slight reduction of revertants

OTHER DATA:
The various mutagens, promutagens, sterility checks, sensitivity and resistance tests, etc., employed to ensure the test system was acceptable, all produced results within the testing laboratories established limits. There were no known circumstances or occurrences in this study that were considered to have affected the quality or integrity of the data.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

Table 1: Number (arithmetic mean) of colonies of histidine-prototrophic back-mutants in experiments without microsomal activation (original experiment).

Concentration (µg/plate)	TA98	TA100	TA1535	TA1537	TA102
0	11	116	9	6	181
61	11	98	9	6	130
185	16	98	8	6	138
555	13	99	9	6	149
1666	12	101	9	3	141
5000	9	94	9	3	90
2-Nitrofluorene	1814
Sodium azide		1063	936
9-Aminoacridine		1631		6(control)
Mitomycin-C					1097

 Table 2: Number (arithmetic mean) of colonies of histidine-prototrophic back-mutants in experiments with microsomal activation (original experiment).

Concentration (µg/plate)	TA98	TA100	TA1535	TA1537	TA102
0	31	115	11	8	212
61	22	109	11	6	172
185	20	107	11	7	170
555	17	98	10	6	182
1666	19	109	12	5	159
5000	17	104	13	5	109
2-Aminoanthracene		1146		92
Cyclophosphamide	1016		385		1811

 Table 3: Number (arithmetic mean) of colonies of histidine-prototrophic back-mutants in experiments without microsomal activation (confirmatory experiment).

Concentration (µg/plate)	TA98	TA100	TA1535	TA1537	TA102
0	19	129	13	8	215
61	18	115	12	5	199
185	17	124	11	5	151
555	19	100	11	5	139
1666	17	105	11	4	147
5000	13	103	12	4	140
2-Nitrofluorene	1759
Sodium azide		1153	933
9-Aminoacridine				1895
Mitomycin-C					1421

 Table 4: Number (arithmetic mean) of colonies of histidine-prototrophic back-mutants in experiments with microsomal activation (confirmatory experiment).

Concentration (µg/plate)	TA98	TA100	TA1535	TA1537	TA102
0	37	137	10	7	301
61	35	138	11	8	251
185	32	119	10	7	193
555	28	117	11	5	192
1666	29	110	11	6	196
5000	21	110	11	4	142
2-Aminoanthracene	1768	2092		278	1892
Cyclophosphamide			418

 

 

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative