1,3,5-triazine-2,4,6(1H,3H,5H)-trione, compound with 1,3,5-triazine-2,4,6-triamine (1:1)

Genetic toxicity: in vivo

Administrative data

Endpoint:

in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus

Remarks:

Type of genotoxicity: chromosome aberration

Type of information:

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

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Comparable to guideline study with acceptable restricitions.

Data source

Reference

Reference 1

Reference Type:

publication

Title:

Unnamed

Year:

1993

Reference 2

Reference Type:

publication

Title:

Evaluation of a Three-Exposure Mouse Bone Marrow Micronucleus Protocol: Results With 49 Chemicals

Author:

Shelby M.D. et al.

Year:

1993

Bibliographic source:

Environ. Mol. Mutagen., 21, 160-179

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)

Deviations:

yes

Remarks:

only 5-7 males per dose used, differing staining agent

Principles of method if other than guideline:

NTP Standard protocol

GLP compliance:

not specified

Type of assay:

micronucleus assay

Test material

Test material information

Constituent 1

Reference substance name:

Melamine

EC Number:

203-615-4

EC Name:

Melamine

Cas Number:

108-78-1

Molecular formula:

C3H6N6

IUPAC Name:

1,3,5-triazine-2,4,6-triamine

Details on test material:

All test chemicals were received from the NTP chemical repository (Radian Corporation, Austin, TX).

Test animals

Species:

mouse

Strain:

B6C3F1

Sex:

male

Details on test animals or test system and environmental conditions:

Male B6C3F1 mice (obtained from the National Toxicology Program production facility at Taconic Farms) of a common age between 9 and 14 weeks and weighing within a 2 g range of a mean weight between 25 and 33 g were used. Additional information on animal husbandry can be found in Tice et al. [1990a].

Administration / exposure

Route of administration:

intraperitoneal

Vehicle:

- Vehicle(s)/solvent(s) used: corn oil

Details on exposure:

Injection volume was 0.4 ml.

Duration of treatment / exposure:

one injection/day on 3 consecutive days

Frequency of treatment:

one injection/day on 3 consecutive days

Post exposure period:

1st study: For evaluation of bone marrow smears animals were sacrificed 24 hours after the 3rd exposure; for evaluation of peripheral blood smears
animals were sacrificed 48 hours after the 3rd exposure
2nd study: animals were sacrificed 24 hours after the 3rd exposure for both evaluation of bone marrow smears and evaluation of peripheral blood smears.

Doses / concentrations

Doses / concentrations 1

Remarks:

Doses / Concentrations:
0; 500; 1000; 2000 mg/kg (1st study)
Basis:

Doses / concentrations 2

Remarks:

Doses / Concentrations:
1000 and 2000 mg/kg (2nd study)
Basis:

No. of animals per sex per dose:

5 (exemption: only 3 animals were scored at the concentration of 2000 mg/kg bw in the first study)

Control animals:

yes, concurrent vehicle

Positive control(s):

7,12-dimethylbenzanthracene (12.5 mg/kg)

Examinations

Tissues and cell types examined:

bone marrow and peripheral blood

Details of tissue and slide preparation:

DETAILS OF SLIDE PREPARATION:
Staining with acridine orange

METHOD OF ANALYSIS:
Bone marrow:
Slides were evaluated for the number of MN-PCE among 2000 PCE and for the percentage of PCE among 200 erythrocytes.
Peripheral blood:
According to the NTP-Standard protocol 2000 PCEs are evaluated for the number of MN-PCE and 1000 erythrocytes are evaluated for teh percentage of PCE among erythrocytes.

Evaluation criteria:

Statistically significant increase in micronuclei.

Statistics:

When corn oil solvent control data were compared (two-tailed t-test) between laboratories, there was no statistically significant differences. But for PBS, the mean of ILS was significantly higher than that for EHRT (P = 0.009). For the positive control data, there were no significant differences between laboratories.

Results and discussion

Test results

Sex:

male

Genotoxicity:

negative

Toxicity:

no effects

Vehicle controls validity:

valid

Negative controls validity:

not examined

Positive controls validity:

valid

Additional information on results:

No signs of toxicity were observed

Any other information on results incl. tables

Table 1: MN data analysis

	Dose (mg/kg)	MN-PCE/1000 (No. of animals scored)	P value (a)	Survival	%PCEs (b)
1^st study, bone marrow (Sample collection time: 24 hours)			0.003
	0	2.10 +/- 0.62 (5)		5/5	57.3
	500	1.80 +/-0.34 (5)	0.685	5/5	56.6
	1000	2.20 +/- 0.25 (5)	0.439	5/5	57.1
	2000	3.80 +/- 0.70 (5)	0.013	6/6	56.1
	Positive control	6.90 +/- 0.87 (5)	0.0001	-	-
2^nd study, bone marrow (Sample collection time: 24 hours)			0.340
	0	4.60 +/- 0.64 (5)		5/5	60.9
	1000	4.20 +/- 1.21 (5)	0.596	5/5	51.7
	2000	5.30 +/- 1.59 (5)	0.344	5/6	56.3
	Positive control	8.40 +/- 0.56 (5)		-	-
1st study, peripheral blood (c) (Sample collection time: 48 hours)			0.964
	0	2.70 +/- 0.26 (5)		5/5	1.2
	500	3.50 +/- 0.91 (5)	0.154	5/5	1.5
	1000	2.40 +/- 0.56 (5)	0.663	5/5	1.1
	2000	1.50 +/- 0.76 (3)	0.940	3/5	1.2
2nd study, peripheral blood (Sample collection time: 24 hours)			0.411
	0	4.10 +/- 0.73 (5)		no data available	no data available
	1000	3.60 +/- 0.93 (5)	0.716	no data available	no data available
	2000	4.30 +/- 0.56 (5)	0.413	no data available	no data available
	Positive control	8.40 +/- 0.40 (5)	0.0001	no data available	no data available

(a) omitting the high dose value

 (b) ((No. of PCEs)/(No. of PCEs + No. of NCEs)) x 100

(c) no data on positive control available

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information): negative