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

Monitoring data

Administrative data

Endpoint:

monitoring data

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

1990/05/24 to 1992/03/04

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1992

Report date:

1992

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: Pesticide Assessment Guidelines, Environmental Fate: 166-1 Ground water monitoring. US Environmental Protection Agency

Deviations:

no

GLP compliance:

yes

Type of measurement:

background concentration

Media:

ground water

Test material

Test material information

Constituent 1

Reference substance name:

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

EC Number:

266-257-8

EC Name:

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

Cas Number:

66215-27-8

Molecular formula:

C6H10N6

IUPAC Name:

N2-cyclopropyl-1,3,5-triazine-2,4,6-triamine

Study design

Details on sampling:

Samples of soil and ground water were collected before and after spraying at regular intervals up to 307 days after the last treatment.

Results and discussion

Concentration

Concentration 1

Key result

Country:

United States (the)

Location:

South Florida

Substance or metabolite:

metabolite

Remarks:

Melamine

Conc.:

0.1 other: µg/kg

Remarks on result:

other: following day 176

Concentration 2

Key result

Country:

United States (the)

Location:

South Florida

Substance or metabolite:

substance

Remarks:

Cyromazine

Conc.:

0.1 other: µg/kg

Remarks on result:

other: following day 176

Details on results:

Movement of cyromazine in soil was not detected below a 0-15 cm soil depth. In the 0-15 cm soil layer residues were as high as 47 µg/kg (subplot B) after the fourth application but decreased significantly from day 61 after the last (sixth) application. The great variability of cyromazine residues in the 0-15 cm soil samples was attributed to the foliar treatment and to the agricultural practices (plastic covered bedded-up rows). Melamine did exhibit some intermittent movement to the 15-30 cm soil depth. Residues of cyromazine and of melamine were below the detection limit of 0.1 µg/kg in all soil samples after day 176.
Actual breakthrough of bromide into ground water was inconclusive due to the limited amount of detections in the well samples. Analyses of the water samples from the 10 monitoring wells taken at 29 time intervals during the treatment period and up to 307 days after the last treatment showed no detectable residues of cyromazine at the screening level of 0.10 µg/L. Only sporadic trace levels in the range of 0.10 to 0.21 µg/L of the metabolite melamine were detected in 6 out of 290 water samples.
During the first three months of the study duration the field was drastically irrigated. Therefore the conditions can be considered as a worst-case scenario regarding leaching. It was concluded that due to lack of detection of cyromazine and the degradate melamine in the monitoring wells following typical agronomic practices for tomato production in southern Florida the use of cyromazine results in no potential impact on ground water resources.

Any other information on results incl. tables

Table 2: Florida ground water monitoring study, results of soil residue analysis

Days after last application^$	Cyromazine (mg/kg)*			Melamine (mg/kg)*
	0 - 15 cm	15 - 30 cm	30 - 46 cm	0 - 15 cm	15 - 30 cm	30 - 46 cm
-1	< 0.010	< 0.010	< 0.010	< 0.010	< 0.010	< 0.010
0 (1)	0.0109	< 0.010	< 0.010	< 0.010	< 0.010	< 0.010
-1	< 0.010	< 0.010	< 0.010	0.0133	< 0.010	< 0.010
0 (2)	0.0143	< 0.010	< 0.010	0.0159	< 0.010	< 0.010
+6	< 0.010	< 0.010	< 0.010	0.0118	< 0.010	< 0.010
-1	< 0.010	< 0.010	**	0.0139	< 0.010	**
0 (3)	< 0.010	< 0.010	**	0.0177	< 0.010	**
+6	< 0.010	< 0.010	**	0.0118	< 0.010	**
-1	0.0139	< 0.010	**	0.0378	0.0192	**
0 (4)	0.0216	< 0.010	**	0.0472	< 0.010	**
+6	0.0312	< 0.010	**	0.0276	0.0140	**
-1	0.0111	< 0.010	**	0.0194	< 0.010	**
0 (5)	0.0191	< 0.010	**	0.0447	0.0107	**
-1	0.0149	< 0.010	**	0.0210	< 0.010	**
0 (6)	0.0145	< 0.010	**	0.0232	< 0.010	**
1	0.0115	< 0.010	**	0.0202	0.0138	**
3		< 0.010	**	0.0464	< 0.010	**
7	0.0159	< 0.010	**	0.0152	< 0.010	**
14	0.0307	< 0.010	**	0.0252	< 0.010	**
30	0.0340	< 0.010	< 0.010	0.0446	< 0.010	< 0.010
61	0.0138	< 0.010	< 0.010	0.0293	< 0.010	< 0.010
91	0.0119	< 0.010	< 0.010	0.0252	< 0.010	< 0.010
120	0.0253	< 0.010	< 0.010	0.0414	< 0.010	< 0.010
152	0.0203	< 0.010	< 0.010		< 0.010	< 0.010
176	0.0111	< 0.010	< 0.010	0.0295	0.0149	< 0.010
216	< 0.010	< 0.010	< 0.010	0.0174	< 0.010	< 0.010
246	< 0.010	< 0.010	< 0.010	0.0198	< 0.010	< 0.010
273	0.0106	< 0.010		0.0265	< 0.010	**
307	< 0.010	< 0.010	< 0.010	0.0298	< 0.010	< 0.010

^$: number of application in brackets; negative values: days before next application

*Average from three subplots

** samples not taken due to water table depth of 46 cm

 

Table 3: Florida ground water monitoring study, precipitation during study duration

Month	Monthly precipitation 1976 - 1986 *		Irrigation and precipitation for study duration
	(mm)	Cumulative (mm)	(mm)	Cumulative (mm)
September	176.3	176.3	1609.3	1609.3
October	46.5	222.8	1393.7	3028.4
November	49.3	272.0	494.0	3522.5
December	58.7	330.7	11.7	3534.2
January	69.1	399.8	79.0	3613.2
February	87.4	487.2	23.9	3637.0
March	80.3	567.4	138.7	3775.7
April	37.6	605.0	97.0	3873.0
May	96.0	701.0	217.2	4090.2
June	160.0	861.1	105.4	4195.6
July	191.8	1052.8	257.3	4452.9
August	198.9	1251.7	169.9	4622.8
September	176.3	1428.0	97.3	4720.1

*Source: National Weather Service, Ruskin, Florida

Applicant's summary and conclusion

Conclusions:

During the first three months of the study duration the field was drastically irrigated. Therefore the conditions can be considered as a worst-case scenario regarding leaching. It was concluded that due to lack of detection of cyromazine and the degradate melamine in the monitoring wells following typical agronomic practices for tomato production in southern Florida the use of cyromazine results in no potential impact on ground water resources.

Executive summary:

A small-scale prospective ground water monitoring study was conducted in a worst-case hydrogeologically vulnerable area in South Florida. It represents typical practices for tomato production and for use of the test substance in an extreme worst-case environment with respect to potential for ground water contamination associated with the use of agricultural chemicals.

Ten monitoring wells were installed at the test site prior to application of cyromazine with a ground boom sprayer at a rate of six times 140 g a.s./ha over a period of 8 weeks beginning September 12, 1990. Sodium bromide was applied as the reference substance to monitor chemical movement.

During the first three months of the study duration the field was drastically irrigated. Therefore the conditions can be considered as a worst-case scenario regarding leaching. It was concluded that due to lack of detection of cyromazine and the degradate melamine in the monitoring wells following typical agronomic practices for tomato production in southern Florida the use of cyromazine results in no potential impact on ground water resources.