Registration Dossier

Environmental fate & pathways

Additional information on environmental fate and behaviour

Administrative data

Endpoint:
additional information on environmental fate and behaviour
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2009-12-17 - 2010-04-15
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
test procedure in accordance with generally accepted scientific standards and described in sufficient detail
Cross-referenceopen allclose all
Reason / purpose:
reference to other study
Reference
Endpoint:
adsorption / desorption: screening
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2009-03-11 - 2009-12-10
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Qualifier:
according to
Guideline:
OECD Guideline 106 (Adsorption - Desorption Using a Batch Equilibrium Method)
Deviations:
no
GLP compliance:
yes (incl. certificate)
Type of method:
batch equilibrium method
Media:
soil
Specific details on test material used for the study:
Molecular weight: 153.2 g/mol
Molecular formula: C7H11N3O
Purity: 99.9 %
Radiolabelling:
no
Test temperature:
20°C
Details on study design: HPLC method:
The analysis of the water phases (blank values and equilibrium concentrations) is based on the highly specific high performance liquid chromatography with mass-spectrometric detection (LC-MS/MS).
The analytical method for the determination of N-[(3(5)-Methyl-1H-pyrazol-1-yl)methyl]acetamide (P 70/05) in water was developed by SGS INSTITUT FRESLNIUS GmbH. The analytical method was proved to be valid within the course of the study.
The detection mode of N-[(3(5)-Methyl-1H-pyrazol-1-yl)methyl]acetamide (P 70/05) is based on an electrospray ionization technique (LSI positive).
Analytical monitoring:
yes
Details on matrix:
LUFA 2.1: July 15, 2009 (batch no.: F2.1 2909, SGS INSTITUT FRESENIUS GmbH identification: 010/9128400), depth of soil collcction was down to 20 cm), Germany, Rheinland- Pfalz, Dudenhofen, Am Hauhofcr Weg links, Nr. 3336/58, location of soil collection of no agricultural use, agricultural plant protection products not used for the sampling year and 4 former years, fertilization performed in 2007: 600 kg/ha CaO I 250 kg/ha MgO.
Soil type: silty sand (DIN) or sand (USDA)
LUFA 2.2: July 15, 2009 (batch no.: F2.2 2909, SGS INSTITUT FRESENIUS GmbH identification: 010/9128451), depth of soil collection was down to 20 cm), Germany, Rheinland- Pfalz, Hanhofen, Großer St riet, Nr. 585, meadow, agricultural plant protection products not used for the sampling year and 4 former years, fertilization performed in 2007: 600 kg/ha CaO + 250 kg/ha MgO.
Soil type: loamy sand (DIN and USDA)
• LUFA 2.3: July 16, 2009 (batch no.: F2.3 2909, SGS INSTITUT FRESENIUS GmbH identification: 010/9128452), depth of soil collection was down to 20 cm), Germany, Rheinland- Pfalz, Offenbach, Im Bildgarten Nr. 507, fallow soil and pumpkin, agricultural plant protection products not used for the sampling year and 4 former years, fertilization performed in 2005 (300 kg/ha): 12 % N, 12 % P205, 17 % K20.
Soil type: silty sand (DIN) or sandy loam (USDA)
The collection and sieving (2 mm screen) of soils was perfomied by LUFA Speyer, Obere Langgasse 40, 67346 Speyer, Germany. LUFA Speyer provided soil certificates for the German standard soils 2.1 (F2.1 2909), 2.2 (F2.2 2909) and 2.3 (F2.3 2909) including information on the history of the soils, geographical information on the German soil locations and characterization data.Soil aliquots were air dried at room temperature and stored in tightly closed all-plastic storage container at ambient temperature (approximately 20 °C). Prior to use the soil moisture analysis was carried out by heating soil aliquots at 105 °C overnight. The soil dry matter content was 99 %. Therefore, the degree of soil humidity was not taken into account for the preparation of the test systems.
Details on test conditions:
The test systems were composed of the test item dissolved completely in aqueous CaCl2 solution (0.01 mol/L) and soil, all placed in tightly closed all-plastic centrifuge bottles (125 mL). The co- solvent (methanol) added to the aqueous solution by test item dosing did not excced 0.1 vol. %.
A CaCl2 solution was used to minimize cation exchange.
Prior to use, experimental soils (sieved: < 2mm, air dried, soil moisture of 1 %) were equilibrated using 0.01 mol/L CaCl2 solution. Equilibration of soil was carried out by shaking (200 strokes/min) a calculated amount of soil with a volume of 59 mL of 0.01 mol/L CaCl2 solution for overnight (17 h) before the day of the experiment.
Afterwards a calculated volume of the test item solution (1 ml.,; 6.35 f.tg/mL P 70/05) was added to the slurry. By the addition of the test item solution the aqueous phase of the slurry was adjusted to 60 mL and the aimed test concentration of 0.1 mg/L P 70/05 was reached.
The soil and treated 0.01 mol/L CaCl2 solution were gently tumbled. The agitation device kept the soil in suspension during shaking (200 strokes/min). Soil (solid phase) and aqueous phase weic separated by centrifugation (4000 rpm for 5 min) and the aqueous phase removed as much as possible. The volume of the removed aqueous phase was recorded.
The adsorption equilibrium time was set to 24 hours.
The experiment was conducted at 20 + 2 °C in the dark, using analytical grade P 70/05, namely N- [(3(5)-Methyl-1H-pyrazol-1 -yl)methyl]acetamide.
Each test system was prepared in triplicate.
For the experiment three German Standard soils were used (sec section 7.1). The experimental soils were selected by the Sponsor, as was the test concentration.
The ratio of aqueous CaCl2 solution to dry soil for the adsorption test was:
• ratio 1:1 60 mL aqueous solution and 60 g dry soil
• ratio 5:1 60 mL aqueous solution and 12 g dry soil
The distribution of N-[(3(5)-Methyl-1H-pyrazol-1-yl)methyl]acetamide (P 70/05) between the water phase and the solid phase was investigated. LC-MS/MS was used for the analysis of the equilibrium concentration in the water phases. The adsorbed N-[(3(5)-Methyl-1H-pyrazol-1-yl)methyl]acetamide (P 70/05) in the solid phase (soil) was calculated.
Adsorption Test
The selection of solution/soil ratios was performed on
• ratio 1:1 60 mL aqueous solution and 60 g dry soil
• ratio 5:1 60 mL aqueous solution and 12 g dry soil
The test item concentration was adjusted to 0.1 mg/L. The experimental soils were pre-conditioned (see section. The test systems were tumbled (20 ± 2 °C in the dark, laboratory shaker at 200 strokes/min, 125 mL all-plastic centrifuge vessel) for 24 hours.
A time period of 24 hours maximum was assumed to be sufficient for reaching equilibrium.
After centrifugation (4000 ipm for 5 min) specimen aliquots of the supernatants were filtered using a membrane filter (OA, 0.45 pm). Specimen aliquots of 0.05 mL, taken at the 24 hours time point, were diluted with 0.95 mL of methanol/water/formic acid; 10/90/0.1, v/v/v and subjected to LC- MS/MS analysis.
Sample No.:
#1
Duration:
24 h
Temp.:
20 °C
Key result
Sample No.:
#1
Type:
Koc
Value:
2 L/kg
pH:
5.57
Temp.:
20 °C
Matrix:
LUFA 2.1
% Org. carbon:
0.74
Remarks on result:
other: ratio 1:1
Key result
Sample No.:
#2
Type:
Koc
Value:
7.5 L/kg
pH:
6.48
Temp.:
20 °C
Matrix:
LUFA 2.2
% Org. carbon:
2.09
Remarks on result:
other: ratio 1:1
Key result
Sample No.:
#2
Type:
Koc
Value:
10 L/kg
pH:
6.48
Temp.:
20 °C
Matrix:
LUFA 2.2
% Org. carbon:
2.09
Remarks on result:
other: ratio 5:1
Key result
Sample No.:
#3
Type:
Koc
Value:
34.9 L/kg
pH:
7.09
Temp.:
20 °C
Matrix:
LUFA 2.3
% Org. carbon:
0.97
Remarks on result:
other: ratio 1:1
Key result
Sample No.:
#3
Type:
Koc
Value:
34.5 L/kg
pH:
7.09
Temp.:
20 °C
Matrix:
LUFA 2.3
% Org. carbon:
0.97
Remarks on result:
other: ratio 5:1
Recovery of test material:
The recovery of N-[(3(5)-Methyl-1H-pyrazol-1-yl)methyl]acetamide (P 70/05) in the 0.01 mol/L CaCl2 solution (pH-value: 6.34) at a test concentration of 0.1 mg/L was 101.2 % (RSD of 0.4 %) after agitation for 24 hours at 20 °C in the dark.
Sample no.:
#1
Duration:
24 h
% Adsorption:
1
Remarks on result:
other: ratio 1:1
Sample no.:
#1
Duration:
24 h
% Adsorption:
0
Remarks on result:
other: ratio 5:1
Sample no.:
#2
Duration:
24 h
% Adsorption:
14
Remarks on result:
other: ratio 1:1
Sample no.:
#2
Duration:
24 h
% Adsorption:
4
Remarks on result:
other: ratio 5:1
Sample no.:
#3
Duration:
24 h
% Adsorption:
25
Remarks on result:
other: ratio 1:1
Sample no.:
#3
Duration:
24 h
% Adsorption:
6
Remarks on result:
other: ratio 5:1
Transformation products:
not measured
Validity criteria fulfilled:
yes
Conclusions:
N-[(3(5)-Melhyl-1H-pyrozol-1-yl)methyl]acetamide (P 70/05) showed a low tendency (o adsorb onto the experimental soils.
The adsorption coefficients on the basis of soil organic carbon content (Koc) were calculated to be:
• LUFA 2.1 soil lest system 2.0 mL/g (ratio L1) at 0.74 % org. carbon
• LUFA 2.2 soil test system 7.5 mL/g (ratio 1:1) at 2.09 % org. carbon
• LUFA 2.3 soil test system 34.9 mL/g (ratio 1:1) at 0.97 % org. carbon
Executive summary:

The extent of adsorption of N-[(3(5)-Methyl-1H-pyrazol-1 -yl)methyl]acetamidc (P 70/05) was studied on basis of the OECD/OCDH Guideline no.106 for the testing of chemicals, adopted January 21, 2000. The study was conducted with analytical grade N-[(3(5)-Methyl-lH-pyrazol-l-yl)mcthylJacetamide (99.9 %) test item.

Following the equilibration of the three German soil systems (soil textures according to DIN/US DA classification were: silty sand/sand for TUFA 2.1 soil, loamy sand for LUFA 2.2 soil, silty sand/sandy loam for TUFA 2.3 soil) with 60 mL of 0.01 mol/L CaCl2, the lest item was applied in 0.01 mol/T CaCI2. The co-solvent (methanol) added to the aqueous solution by test item dosing did not excced 0.1 vol, %.

The adsorption test was performed on two soil/solution ratios of 1:1 (60 mT of 0.01 mol/L CaCl; and 60 g dry soil) and 5:1 (60 mL of 0.01 mol/L CaCI2and 12 g diy soil) using one test concentration of N-[(3(5)-Methyl-l H- pyrazol-1 -yl)methyl]acetamide (0.1 mg/L).

After agitation for 24 hours at 20 °C ill ihe dark, the distribution of N-[(3(5)-Methyl-lH-pyrazol-1-yl)melhyl]- acetamide (P 70/05) between the aqueous phase and the solid phase (soil) was assayed. LC-MS/MS was used for the analysis of the equilibrium concentration in the aqueous phases. The adsorbed N-[(3(5)-Methyl-1H-pyrazol- 1 -yl)methyl]acetamide (P 70/05) in the solid phase (soil) was calculated,

N-[(3(5)-Melhyl-1H-pyrazol-l-yl)methyl]acetamide (P 70/05) showed a low tendency to adsorb onto the experimental soils.

The adsorption coefficients on the basis of soil organic carbon content (Koc) were calculated to be:

     LUFA 2.1 soil lest system             2.0 mL/g (ratio L1) at 0.74 % org. carbon

     LUFA 2.2 soil test system             7.5 mL/g (ratio 1:1) at 2.09 % org. carbon

     LUFA 2.3 soil test system             34.9 mL/g (ratio 1:1) at 0.97 % org. carbon

Reason / purpose:
reference to other study
Reference
Endpoint:
biodegradation in soil: simulation testing
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2009-03-24 - 2009-12-01
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Qualifier:
according to
Guideline:
OECD Guideline 307 (Aerobic and Anaerobic Transformation in Soil)
Deviations:
no
GLP compliance:
yes (incl. certificate)
Test type:
laboratory
Specific details on test material used for the study:
Chemical name: N-[(3(5)-Methyl-1H-pyrazol-1-yl)methyl]acetamide
Molecular weight: 153.2 g/mol
Molecular formula: C7H^11N3O
Purity: 99.9%
Radiolabelling:
no
Oxygen conditions:
aerobic
Soil classification:
DIN 19863 (Deutsche Industrie-Norm)
Soil no.:
#1
Soil type:
other: silty sand/sand
% Org. C:
0.74
pH:
5.1
CEC:
4 meq/100 g soil d.w.
Soil no.:
#2
Soil type:
loamy sand
% Org. C:
2.09
pH:
5.5
CEC:
10 meq/100 g soil d.w.
Soil no.:
#3
Soil type:
other: silty sand
% Org. C:
0.97
pH:
6.6
CEC:
9 meq/100 g soil d.w.
Details on soil characteristics:
LUFA 2.1: July 15, 2009 (batch no.: F2.1 2909, SGS INSTITUT FRESENIUS GmbH identification: 010/9378965), depth of soil collection was down to 20 cm), Germany, Rheinland- Pfalz, Dudenhofen, Am Hanhofer Weg links, Nr. 3336/58, location of soil collection of no agricultural use, agricultural plant protection products not used for the sampling year and 4 former years, fertilization performed in 2007: 600 kg/ha CaO + 250 kg/ha MgO.
Soil type: silty sand (DIN) or sand (USDA).

LUFA 2.2: July 15, 2009 (batch no.: F2.2 2909, SGS INSTITUT FRESENIUS GmbH identification: 010/9378966), depth of soil collection was down to 20 cm), Germany, Rheinland- Pfalz, Hanhofen, Großer Striet, Nr. 585, meadow, agricultural plant protection products not used for the sampling year and 4 former years, fertilization performed in 2007: 600 kg/ha CaO + 250 kg/ha MgO.
Soil type: loamy sand (DIN and USDA)

LUFA 2.3: July 16, 2009 (batch no.: F2.3 2909, SGS INSTITUT FRESENIUS GmbH identification: 010/9378967), depth of soil collection was down to 20 cm), Germany, Rheinland- Pfalz, Offenbach, Itn Bildgarten Nr. 507, fallow soil and pumpkin, agricultural plant protection products not used for the sampling year and 4 former years, fertilization performed in 2005 (300 kg/ha): 12 % N, 12 % P205, 17 % K20.
Soil type: silty sand (DIN) or sandy loam (USDA).



Soil No.:
#1
Duration:
29 d
Soil No.:
#2
Duration:
29 d
Soil No.:
#3
Duration:
29 d
Soil No.:
#1
Initial conc.:
0.48 mg/kg soil d.w.
Based on:
test mat.
Soil No.:
#2
Initial conc.:
0.48 mg/kg soil d.w.
Based on:
test mat.
Soil No.:
#3
Initial conc.:
0.48 mg/kg soil d.w.
Based on:
test mat.
Parameter followed for biodegradation estimation:
test mat. analysis
Soil No.:
#1
Temp.:
20°C
Humidity:
45 % MWHC
Microbial biomass:
22 mg C/100 g soil
Soil No.:
#2
Temp.:
20°C
Humidity:
45 %MWHC
Microbial biomass:
34 mg C/100 g soil
Soil No.:
#3
Temp.:
20°C
Humidity:
45 % MWHC
Microbial biomass:
14 mg C/100 g soil
Details on experimental conditions:
Amounts of conditioned soil at 45 % MWHC equivalent to 100 g dry weight were bottled into 1000 mL all glass metabolism flasks (conical shoulder bottles of 10 cm inner diameter) and maintained under a dynamic atmosphere of air, in the dark, at 20 °C ± 2 °C (see experimental set-up, Section: 7.3). Air entering the system was passed through a washing bottle to reduce the water loss of soil. The metabolism flasks were connected via tubing. A flow meter was used to measure on a weekly basis the air at a flow rate of about 15 to 30 mL/min.
The application of the test item was made to the soil surface,
Each test vessel was allocated a number that was used internally during the experimental phase.
Fortification
The soil (equivalent to 100 g dry weight) was treated at 0.48 mg a.s./kg soil (dry weight).
The test item (see section 8) was applied in 192 ^iL (249.8 pg/mL) of a mixture of methanol/water (10/90; v/v) onto the surface of the soil. The volume of methanol added to 100 g of dry soil did not exceed 0.1 vol. % (w/w). The treated soils were thoroughly mixed, by manual shaking, to incorporate the test item into soil. Following fortification the specimens were incubated for the appropriate amount of time under the conditions previously described.
The application solution (one at the beginning of dosing and one at the completion of dosing) was analyzed each in triplicate by LC-MS/MS to determine the measured concentration of N-[(3(5)- Methyl-lH-pyrazol-l-yl)methyl]acetamide (P 70/05). The recovery range accounted for 97 - 98 % of the theoretic value, based on the primary mass transition m/z 154 —> m/z 83.
The homogeneity of the application solution and the stability of the test item were reflected by the calculated standard deviation of N-[(3(5)-Methyl-lH-pyrazol-l-yl)methyl]acetamide (P 70/05) concentrations found (mean value of 97.3 % and RSD of 0.5 %).
For determination of the microbial activity at the start and end of the experiments (J. P. E. Anderson and K. H. Domsch, "A physiological method for the quantitative measurement of microbial biomass in soils'1), no test item was used.
7.5 Incubation
The test vessels were placed in a constant temperature room at 20 °C, with a temperature control of ± 2 °C and incubated in the dark. The temperature was recorded. Specimens were weighed approximately every two weeks to ensure that the soil moisture is being maintained. If the soil moisture e.g. dropped more than 10 % below this value (in weight equivalents), reagent water was added until the desired moisture level was obtained.
Sampling
Soil specimens were assayed at zero-time (initial value), 1,3, 7, 13 and 29 days after fortification. At each sampling interval replicate specimens were taken and assayed for the test item (P 70/05) and 3- Methylpyrazole.
The validity of the analytical method was proven for N-[(3(5)-Methyl~lH-pyrazol-l-yl)methyl]- acetamide (P 70/05) and 3-Methylpyrazole within each specimen sequence, using two freshly prepared adequate fortification values for each soil type.
Method Validation
Prior to the start of the N-[(3(5)-Methyl-lH-pyrazol-l-yl)methyl]acetamide (P 70/05) investigations in soil, the analytical method was established and validated by analysis of N-[(3(5)-Methyl-lH- pyrazol-l-yl)methyl]acetamide (P 70/05) and 3-Methylpyrazole (possible degradate of P 70/05) applied to and extracted from the experimental soils (see Section 9).
Soil blanks (100 g dry weight) conditioned at 45 % MWHC were fortified each with approximately 0.48 mg and 0.01 mg N-[(3(5)-Methyl-lH-pyrazol-l-yl)metliyl]acetamide (P 70/05) per kilogram dry soil equivalent to 100 and 2 % of the target rate.
Soil blanks (100 g dry weight) conditioned at 45 % MWHC were fortified each with approximately 0.26 mg and 0.005 mg 3-Methylpyrazole per kilogram dry soil.
The extraction and analytical method is considered valid since the following criteria for each analyte are fulfilled:
the blank values were not higher than 30 % of the LOQ (LOQ equivalent to the lowest fortification level)
the mean recovery at each fortification level and for each soil matrix is in the range 70-110 %
the relative standard deviation for each fortification level and for each soil matrix is less or equal 20 %
the overall relative standard deviation for each soil matrix and analyte is less or equal 20 %
Specimen Processing
The conditioned soil (45 % MWHC equivalent to 100 g dry soil) was placed in a 250 mL centrifuge bottle (method validation/laboratory concurrent recovery specimens: fortification at this point). 150 mL of the extraction solvent methanol/water/formic acid (50/50/0.1; v/v/v) were added. For specimens derived from the soil degradation study, the soil was quantitatively transferred into the centrifuge vessel using portions of the 150 mL volume of the extraction solvent.
The specimen was shaken for several seconds by hand, subjected to ultrasonic agitation for 10 minutes and finally subjected to a shaking machine (30 min at 270 strokes/min). After centrifugation for 5 minutes at 4000 rpm the supernatant was filtered over glass wool into a 250 mL volumetric flask. The extraction procedure was repeated two times using portions of 50 mL of the extraction solvent. The supernatants on a specimen basis were combined. The volumetric flask was filled up to the mark using the extraction solvent (final volume: 250 mL).
Further dilutions of the specimen extract were performed by the addition of methanol/water/formic acid (10/90/0.1; v/v/v). The final specimen extracts were subjected to LC-MS/MS analysis.
Key result
Soil No.:
#1
DT50:
2.31 d
Type:
(pseudo-)first order (= half-life)
Temp.:
20 °C
Key result
Soil No.:
#2
DT50:
0.7 d
Type:
(pseudo-)first order (= half-life)
Temp.:
20 °C
Key result
Soil No.:
#3
DT50:
1.05 d
Type:
(pseudo-)first order (= half-life)
Temp.:
20 °C
Transformation products:
yes
No.:
#1
Evaporation of parent compound:
not specified
Volatile metabolites:
not specified
Residues:
not specified
Conclusions:
The degradation of N-[(3(5)-Methyl-1H-pyrazol-1-yl)methyl]acetamide (P 70/05) was investigated under aerobic conditions at 20 °C. Three German soils of different characteristics were used for the experiment (LUFA 2.1 - silty sand/sand, LUFA 2.2 - loamy sand and LUFA 2.3 - silty sand/sandy loam). The formation of 3-Methylpyrazole, a possible degradate of P 70/05, was monitored.
N-[(3(5)-Methyl-1H-pyrazol-1-yl)methyl]acetamide (P 70/05) degraded fastly in the soil test systems.
The DT-50 values of P 70/05 in the soils LUFA 2.1, LUFA 2.2 and LUFA 2.3 soil were 2.31, 0.70 and 1.05 days.
The DT-90 values of P 70/05 in the soils LUFA 2.1, LUFA 2.2 and LUFA 2.3 soil were 7.68, 2.32 and 3.31 days.
Within the course of the P 70/05 degradation, the original isomers ratio of P 70/05 changed.
The formation of 3-Methylpyrazole reached a maximum of 0.1331 mg/kg on day-3 in soil LUFA 2.3. On day-29 the analysed value for 3-Methylparazole accounted for 0.0158 and 0.0193 mg/kg in soil LUFA 2.3.
Executive summary:

N-[(3(5)-Methyl-lH-pyrazol-l-yl)methyl]acetamide (P 70/05) was tested in aerobic soil on the basis of OECD/OCDE Guideline no.307 for the testing of chemicals, adopted April 24, 2002. The study was performed in the laboratory using analytical grade N-[(3(5)-Methyl-lH-pyrazol-l- yl)methyl]acetamide (purity of 99.9 %). The degradation of N-[(3(5)-Methyl-lH-pyrazol-l- yl)methyl]acetamide (P 70/05) was investigated under aerobic conditions at 20 °C.The formation of 3-Methylpyrazole, a possible degradate ofP 70/05, was monitored.Three German soils of different characteristics were used for the experiment (see Section 12.4).The test concentration of 0.48 mg/kg dry soil was based on a penetration depth of the test item in the soil of 10 cm, a soil bulk density of 1 g/cm3and on a total use of 480 g a.s./ha/year (0.2 % active substance based on application of total mass of 240 kg fertilizer N present as ammonium nitrogen and urea nitrogen).The soil systems were acclimatized under a dynamic atmosphere of air to maintain aerobic conditions. The test period consisted of sampling intervals at zero time, 1, 3,7, 13 and 29 days.The recoveries of N-[(3(5)-Methyl-lH-pyrazol-l-yl)methyl]acetamide (P 70/05) for the initial time specimens of the aerobic soil degradation experiment ranged from 92 to 95 % of the applied test item.For the description of the disappearance time of N-[(3(5)-Methyl-lH-pyrazol-l-yl)methyl]acetamide (P 70/05), a 1storder kinetic was chosen. N-[(3(5)-Methyl-lH-pyrazol-l-yl)methyl]acetamide (P 70/05) degraded fastly in the soil test systems.The DT-50 values of P 70/05 in the soils LUFA 2.1, LUFA 2.2 and LUFA 2.3 soil were 2.31, 0.70 and 1.05 days.The DT-90 values of P 70/05 in the soils LUFA 2.1, LUFA 2.2 and LUFA 2.3 soil were 7.68, 2.32 and 3.31 days.Within the course of the P 70/05 degradation, the original isomers ratio of P 70/05 changed.

The formation of 3-Methylpyrazole reached a maximum of 0.1331 mg/kg on day-3 in soil LUFA 2.3. This value is equivalent to 52 % of the possible value of 3-Methylpyrazole formed by degradation of the applied amount of N-[(3(5)-Methyl-lH-pyrazol-l-yl)methyl]acetamide (P 70/05)to the soil. On day-29 the analysed value for 3-Metliylparazole accounted for 0.0158 and 0.0193 mg/kg in soil LUFA 2.3.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2010
Report Date:
2010

Materials and methods

Principles of method if other than guideline:
PELMO, the PEsticide Leaching MOdel
GLP compliance:
yes (incl. certificate)
Type of study / information:
To assess the leaching potential of N-[(3(5)-Methyl-1H-pyrazol-1-yl)methyl]acetamide (P 70/05) PELMO, the PEsticide Leaching MOdel is used. PELMO is a compartmental model for the simulation of chemical movement in the unsaturated soil system within and below the plant root zone. Transport on the passage of time including advection and dispersion are represented in the program. Sorption is estimated based on the Freundlich equation, degradation of chemicals in soil is corrected based on temperature and soil moisture.

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: crystalline
Details on test material:
Name P70/05
Appearance white to yellow powder
Composition N-[(3(5)-Methyl-1 H-pyrazol-1 -yl)-methyl]acetamide (3:5 =66:34)

Results and discussion

Any other information on results incl. tables

The Computer Simulations

Summary of results

Maximum annual average concentrations in the percolate after 20 years

Results of PELMO 3.0 (soil: Borstel,climate: Hamburg, alternately wet and normal)

crop   Percolate (L/m2) Substance flux Max. annua! av. concentration ( µg/L)

(g/ha)

winter wheat              319.8                 0.000                                     0.000

winter barley              362.3                 0.000                                     0.000

winter rape              334.3                 0.000                                     0.000

maize              409.3                 0.000                                     0.000

In all simulations the depth of the soil core was 110 cm. In the tables above the maximum annual outflow of water below 110 cm is called „Percolate". Dissolved in the percolate the nitrification inhibitor may leave the soil core. The maximum annual amount of the nitrification Inhibitor that is transported below 110 cm is called „substance flux". Based on the substance flux (unit g/ha) and the percolate (unit L/m2) the „Maximum annual average concentration" are calculated. The nominal application rate, the timing of the applications and the numbers of applications per year were dependent on the crop.

Dependent on the actual crop development different reductions due to crop interception was considered.

If the input data on degradation and sorption which were used in the computer simulations are valid under agricultural conditions considerable annual concentrations of N-[(3(5)-Methyl-1H- pyrazol-1-yl)methyl]acetamide (P 70/05) above 0.1 pg/L In the percolate at 1.1 m soil depth are not expected.

Mobility and degradability of a chemical predominantly influence its leaching behaviour. The koc- values available for N-[(3(5)-Methyl-1H-pyrazoi-1-yl)methyl]acetamide (P 70/05) were in the range of 2 L/kg to 34.9 L/kg (soil/water ratio = 5/1, n=2 and soil/water ratio 1/1, n=3) indicating relatively weak sorption to soil. For the simulations a koc value of 17.8 L/kg (ar. mean of 5) was considered.

The experimental DT50 values for N-[(3(5)-Methyl-1H-pyrazol-1-yl)methyl]acetamide (P 70/05) were in the range of 0.7 days to 2.31 days. For the simulations the maximum DT50 value of 2.31 days (related to 40 % field capacity as recommended by German authorities as a standard )   value) was considered representing theworst case situation.

First order kinetics was assumed for the degradation in all simulations. Temperature corrections (Q10-factor of 2.2) and soil moisture corrections (moisture exponent of 0.7) were performed. The correction was in agreement with the European FOCUS recommendations.Four different application patterns were analysed on the basis of the sponsor's information that N- [(3(5)-Methyl-1H-pyrazoM-yl)methyljacetamide (P 70/05) is used in winter wheat, winter barley, winter rape, and maize. The application pattern was selected individually dependent on the crop type and based on information given by the sponsor. Crop interception was considered dependent on the crop and the crop development stage according to the European (FOCUS) and German recommendations (Klein 2006).The standard plant uptake factor of plants 0.5 was used for ail simulations.

All simulations were performed with a single soil scenario (Borstel soil). The Borstel soil is the official soil scenario in German pesticide registration. A single climate variation was considered alternating Hamburg wet (872 mm annual rainfall) and Hamburg normal (778 mm annual rainfall) conditions.

Applicant's summary and conclusion

Conclusions:
Annual percolate concentrations at 110 cm depth were simulated to be 0.000 µg/L N-[(3(5)-Methyl-lH- pyrazol-l-yl)methyl]acetamide (P 70/05) independent on the crop simulated.
Executive summary:

To assess the leaching potential of N-[(3(5)-Methyl-lH-pyrazol-l-yl)methyl]acetamide (P 70/05) PELMO, the PEsticide Leaching MOdel is used. PELMO is a compartmental model for the simulation of chemical movement in the unsaturated soil system within and below the plant root zone. Transport on the passage of time including advection and dispersion are represented in the program. Sorption is estimated based on the Freundlich equation, degradation of chemicals in soil is corrected based on temperature and soil moisture.

Annual percolate concentrations at 110 cm depth were simulated to be 0.000 µg/L independent on the crop simulated.

If the input data on degradation and sorption which were used in the computer simulations are valid under agricultural conditions considerable annual concentrations of N-[(3(5)-Methyl-1H- pyrazol-1-yl)methyl]acetamide (P 70/05) above 0.1 µg/L in the percolate at 1.1 m soil depth are not expected.