Test Material: Nicosulfuron 

 

MRID 48354304 

 

Title: Sarff, P. 2004. Aerobic aquatic metabolism of 14C-nicosulfuron (DPXV9360) in two water/sediment systems. 

 

EPA PC Code: 129008 

 

OCSPP Guideline: 835.4300 

For Cambridge Environmental 

 

Primary Reviewer: Lynne Binari Signature: 

Date: 2/16/12 

 

Secondary Reviewer: Kathleen Ferguson Signature: 

Date: 2/16/12 

 

QC/QA Manager: Joan Gaidos Signature: 

Date: 2/16/12 

Nicosulfuron (PC 129008) MRID 48354304 

Page 3 of 33 

sediment, extractable [14C]residues were 14.2-14.8% of the applied at day 0, a maximum 26.0% at 

60 days and 21.5-22.4% at study termination, while nonextractable [14C]residues increased from 

1.0-1.1% at day 0 to 19.4-20.1% at study termination. For both systems, total evolved CO2 and 

other volatile compounds were each <1% of applied. 

Table 1. Results Summary 

Total System 

Observed 

DT50

(days) 

Calculated 

Half-life 

(days) 

Model 

Parameters 

Transformation Products (% of Applied)1

Major Minor 

Catalonia, Spain lake 

water-silt loam 

sediment (20°C, water 

pH 8.2, sediment pH 

7.8)

ca. 80 82.5 

 C0 = 101.8 

k = -0.0084 

r

2

 = 0.9970 

(2-parameter 

SFO2

) 

IN-37740 (maximum 29.1% 

at 102 days) 

Nonextractable sediment 

residues (maximum 17.7% 

at 102 days) 

IN-V9367 (maximum 5.3% 

at 102 days) 

IN-77799 (maximum 3.0% 

at 102 days) 

IN-HYY21 (maximum 6.6% 

at 102 days) 

CO2 (maximum 0.297% at 

102 days) 

North Dakota lake 

water-sand sediment 

(20°C, water pH 8.3, 

sediment pH 8.2)

ca. 95 101.9 

C0 = 96.2 

k = -0.0068 

r

2

 = 0.9976 

(2-parameter 

SFO) 

IN-37740 (maximum 20.3% 

at 60 days) 

Nonextractable sediment 

residues (maximum 20.1% 

at 102 days) 

IN-V9367 (maximum 4.1% 

at 102 days) 

IN-77799 (maximum 2.3% 

at 102 days) 

IN-HYY21 (maximum 3.2% 

at 102 days) 

CO2 (maximum 0.668% at 

102 days) 

1 IN-37740, IN-77799 and IN-HYY21 contained both the pyridine and pyrimidine labels, while IN-V9367 contained 

only the pyridine label. 

2 SFO means “single first-order” kinetics model. 

I. Materials and Methods 

A. Materials 

1. Test Materials: [Pryidine-2-14C]- and [pyrimidine-2-14C]-nicosulfuron (pp. 19-20). 

Pyridine-2-14C 

Specific activity: 62.9 μCi/mg N

O CH3

O CH3

N

N

H

O

N

H

S

O

O

N

N

H3C

H3C

O

*

Radiochemical purity: ≥96.7% (pp. 19, 25; Figure 5, p. 73) 

Chemical purity: Not reported. 

Lot No.: 2385-050 

Pyrimidine-2-14C 

Specific activity: 62.2 μCi/mg 

N

N

O CH3

O CH3

N

N

H

O

N

H

S

O

O

N

H3C

H3C

O

*

Radiochemical purity: ≥95.1% (pp. 19, 25; Figure 6, p. 74) 

Chemical purity: Not reported. 

Lot No.: 2406-007 
Nicosulfuron (PC 129008) MRID 48354304 

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Solubility in water: 

370 mg/L at pH 4.6 (p. 21) 

390 mg/L at pH 5.1-5.6 

9,000 mg/L at pH 6.3 

15,000 mg/L at pH 6.6 

18,000 mg/L at pH 7.2 

>250,000 mg/L at pH 9.0 

2. Reference Compounds: The following standards were used in the analysis: 

Table 2. Reference Compounds1 

Applicant’s 

Code Name Chemical Name Purity 

(%) Lot No. 

Nicosulfuron 

(DPX-V9360) 

2-[[[[(4,6-Dimethoxy-2-pyrimidinyl)amino]carbonyl]amino]sulfonyl]-N,Ndimethyl-3-pyridinecarboxamide 97.9 116 

IN-V9367 2-(Aminosulfonyl)-N,N-dimethyl-3-pyridinecarboxamide 99.7 3 

IN-37740 2-[[(3,4-Dihydro-6-methoxy-4-oxopyrimidin-2-

yl]aminocarbonyl]aminosulfonyl]-N,N-dimethyl-3-pyridinecarboxamide 

--2 4 

-- 

IN-J0290 4,6-Dimethoxy-2-pyrimidinamine 99.1 3 

IN-H1043 2-Amino-6-hydroxy-4(1H)-pyrimidinone 97.0 7 

IN-74427 2-[(4,6-Dimethoxy-2-pyrimidinyl)-amino]-N,N-dimethyl-3-

pyridinecarboxamide 99.4 2 

IN-W9807 2-[[(4,6-Dimethoxypyrimidin-2-yl)aminocarbonyl]aminosulfonyl]-Nmethyl-3-pyridinecarboxamide 97.2 3 

IN-64554 Isothiaxolo[5,4-B]pyridin-3(2H)-one,1,1-dioxide 99.5 2 

IN-GDC42 2-[[[[(Aminocarbonyl)amino]carbonyl]amino]sulfonyl]-N,N-dimethyl-3-

pyridinecarboxamide -- -- 

IN-77799 2-[(Aminocarbonyl)[4-methoxy-6-(methyldioxy)-2-pyrimidinyl]amino]-

N,N-dimethyl-3-pyridinecarboxamide -- -- 

IN-69188 1-(4,6-Dimethoxypyrimidin-2-yl)pyrido[2,3-d]pyrimidine-2,4-dione -- -- 

IN-H9235 2-Amino-4-hydroxy-6-methoxypyrimidine -- -- 

IN-HYY21 2-[[[[(Aminoiminomethyl)amino]carbonyl]amino]sulfonyl]-N,N-dimethyl3-pyridinecarboxamide -- -- 

Data obtained from pp. 19, 21-22; Figure 1, pp. 65-69 of the study report. 

1 Reference compounds supplied by DuPont Agricultural Products, Wilmington, Delaware. (p. 21). 

2 Information not reported. 

3. Water-sediment: Water-sediment system description and characterization are summarized in 

Table 3 and Tables 4a-4b, respectively. 

Table 3. Water-Sediment Collection and Storage 

Description Estany de Banyoles 

(Lake of Banyoles) Golden Lake 

Geographic location Estany de Banyoles, Catalonia, 

Spain 

Golden Lake, Steele County, 

North Dakota. 

Soil series Not reported. 

Pesticide use history at the collection site Not reported. 

Collection date Not reported. 

Collection 

procedures 

Water: Not reported. 

Sediment: Not reported. 
Nicosulfuron (PC 129008) MRID 48354304 

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Description Estany de Banyoles 

(Lake of Banyoles) Golden Lake 

Storage conditions Sediment stored at ca. 4°C in darkness. Storage conditions of the water 

were not described. 

Storage length Approximately one month; specific intervals/dates were not reported. 

Preparation 

Water: ca. 2-mm sieved. 

Sediment: ca. 2-mm sieved. 

Data obtained from pp. 23, 36 of the study report. 

Table 4a. Properties of the Water-Sediment: Estany de Banyoles 

Parameter 

(unit) 

Field Sampling/Post 

Handling 

Stage of Test Procedure1 

Prior to Test2 During Test End of Test 

Water 

Temperature (oC) -- 

pH 8.2 8.26, 7.83 7.38-8.13 7.17, 7.34 

TOC (mg/L) 2.0 -- -- -- 

O2 (mg/L) -- 8.10, 8.30 5.10-8.50 5.85, 5.83 

Redox potential(mV) +187, +182 +163 to +266 +213, +249 

Sediment 

Sampling Depth (cm) -- 

Soil Texture (USDA) Silt loam 

% Sand 43 

% Silt 52 

% Clay 5 

pH (1:1, soil:water ratio) 7.8 7.78, 7.70 7.33-7.98 7.48, 7.48 

Organic matter (%) Walkley-Black: 2.1 

Furnace method: 1.6 

Organic carbon (%, Walkely-Black with 

heat) 1.2 -- -- 

CEC (meq/100 g) 5.6 

Soil moisture 

content (%) 

At 0 bar: 70.1 

At 1/3 bar: 24.2 

At 1.0 bar: 9.4 

at 15 bar: 4.4 

Bulk density (g/cm3) 0.86 

Microbial biomass (μg/g dry wt.)3 -- 52.9 17.3 

Redox potential (mV) +177, +177 +161 to +252 +215, +248 

Data obtained from pp. 36-37; Table 1, pp. 48-49; Table 4A, p. 53; Table 4C, p. 54 of the study report. Soil texture was 

confirmed using USDA-NRCS technical support tools. 

-- = Not reported. 

1 Treated systems, combined labels (Table 4A, p. 53; Table 4C, p. 54). 

2 Day 0 posttreatment. 

3 Fumigation-extraction method (pp. 36-37). 

Table 4b. Properties of the Water-Sediment: Golden Lake 

Parameter 

(unit) 

Field Sampling/Post 

Handling 

Stage of Test Procedure1 

Prior to Test2 During Test End of Test 

Water 

Temperature (oC) -- 

pH 8.3 8.07, 8.28 7.74-8.52 8.43, 8.51 

TOC (mg/L) 12.2 -- -- -- 

O2 (mg/L) -- 5.44, 6.98 4.50-7.85 5.50, 5.50 
Nicosulfuron (PC 129008) MRID 48354304 

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Parameter 

(unit) 

Field Sampling/Post 

Handling 

Stage of Test Procedure1 

Prior to Test2 During Test End of Test 

Redox potential(mV) +151, +28 +70 to +155.6 +142.5, +132.5 

Sediment 

Sampling Depth (cm) -- 

Soil Texture (USDA) Sand 

% Sand 88 

% Silt 8 

% Clay 4 

pH (1:1, soil:water ratio) 8.2 7.18, 7.03 6.96-8.36 7.62, 8.02 

Organic matter (%, Walkley-Black) 1.6 

Organic carbon (%, Walkely-Black with 

heat) 0.9 -- -- 

CEC (meq/100 g) 11.7 

Soil moisture 

content (%) 

At 0 bar: 45.7 

At 1/3 bar: 12.3 

At 1.0 bar: 9.2 

at 15 bar: 7.2 

Bulk density (g/cm3) 1.10 

Microbial biomass (μg C/g)3 34.2 54.2 

Redox potential (mV) -5, +42 -34 to +161.4 +151.4, +133.4 

Data obtained from pp. 36-37; Table 1, pp. 48-49; Table 5A, p. 55; Table 5C, p. 56 of the study report. Soil texture was 

confirmed using USDA-NRCS technical support tools. 

-- = Not reported. 

1 Treated systems, combined labels (Table 5A, p. 55; Table 5C, p. 56). 

2 Day 0 posttreatment. 

3 Fumigation-extraction method (pp. 36-37). 

B. Study Design

1. Experimental Conditions: Experimental conditions are summarized in Table 5. 

Table 5. Experimental Design 

Parameter Details 

Duration of the test (days) 102 

Water 

Type and size of filter used: ca. 2-mm 

Amount of sediment and water per treatment 

Water: 160 mL total volume 

Sediment: ca. 40 g dry wt. 

Water/sediment ratio: 4:1 (160 mL:40 g dry wt.). 

Control conditions (if used) Sterile controls were not used. 

Pre-treatment acclimation 20 ± 2°C in darkness Estany de Banyoles: 21 days. 

Golden Lake: 13 days. 

Application rates 

Nominal: 0.15 mg a.i./L 

Actual: 

Estany de Banyoles: Pyridine label: 0.152 mg a.i./L 

Pyrimidine label: 0.153 mg a.i./L. 

Golden Lake: Pyridine label: 0.141 mg a.i./L 

Pyrimidine label: 0.139 mg a.i./L 

Number of replicates

Controls (if used): Sterile controls were not used. 
Nicosulfuron (PC 129008) MRID 48354304 

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Parameter Details 

Treatment: 

Per system and label type, twelve water-sediment systems were 

treated to allow for a single system per label/system type at each of 

ten sampling intervals, two reserves. 

Test apparatus 

Type/material/volume: 

Glass gas-washing bottles (250 mL), containing the watersediment system, connected in series (sample train per 

system/label type) to a continuous flow-through (moistened air, 

flow rate not reported) volatiles trapping system. The test 

apparatus is illustrated in Figure 2, p. 70. 

Details of traps for CO2 and other 

volatiles (if any):

In sequence as follows: ethylene glycol (one trap) to collect 

organic volatiles and 1N KOH solution (two traps) to collect CO2; 

trapping solution volumes not reported. 

If no traps were used, is the system 

closed/open? Volatiles traps were used. 

Identity and final concentration (based on 

water volume) of co-solvent 

10mM ammonium 

acetate 

Estany de Banyoles: 0.04-0.06% by 

volume. 

Golden Lake: 0.18-0.19% by volume. 

Test material application method 

Volume of the 

test solution 

used/treatment: 

Estany de Banyoles: 59.9 μL/160 mL for [pyridine-2-14C]-label, 

89.2 μL/160 mL for [pyrimidine-2-14C]-label 

Golden Lake: 304 μL/160 mL for [pyridine-2-14C]-label, 

283 μL/160 mL for [pyrimidine-2-14C]-label 

Application method (e.g., mixed/not 

mixed): 

Test solution applied to surface of water layer using a Rainin EDP 

Plus automatic pipet. 

Any indication of the test material adsorbing 

to the walls of the test apparatus? 

Not indicated. Water-sediment transferred to centrifuge bottles 

using water phase for processing, with system material balances of 

94.8-101.9% of applied at day 0 posttreatment. 

Experimental conditions 

Temperature (C): 20 ± 2C, range not reported 

Continuous darkness: Yes 

Other details (if any) 

Per label type, a water sample (160 mL) was treated in the same 

manner as the water-sediment systems to be used as a dose control. 

Per system type, one untreated water-sediment system (160 mL:40 

g dry wt.) was prepared and maintained to monitor system 

parameters (dissolved oxygen, pH, redox potential) throughout the 

incubation. 

Per system type, two untreated water-sediment systems (1,600 

mL:400 g dry wt.) were prepared in 3-L metabolism vessels 

connected to a continuous air-flow system and maintained for 

biomass determinations at study initiation and termination. 

Per label type, one silt loam sediment (Estany de Banyoles) system 

(160 mL:40 g dry wt.) was treated at a nominal 1 mg a.i./L (10x 

rate) and maintained for possible transformation product 

identification analyses. 

The nominal test application rate of 0.15 μg a.i./g water used in 

this study was reported as equivalent to a field use rate of 450 g 

a.i./ha as applied to a 1 ha body of water of 30-cm depth. This rate 

was reported as ca. 10-fold the maximum field use rate, but was 

required to allow for detection of 1% of the applied radioactivity. 

Data obtained from pp. 19, 23-28; Table 2, p. 50; Tables 6-7, pp. 57-60; Figure 2, p. 70 of the study report. 
Nicosulfuron (PC 129008) MRID 48354304 

Page 8 of 33 

No supplementary studies were described. 

2. Sampling: Sampling details are summarized in Table 6. 

Table 6. Sampling Details 

Criteria Details 

Sampling intervals 

(days) 

Estany de Banyoles: 0, 3, 7, 14, 21, 31, 45, 59, 75 and 102 

Golden Lake: 0, 3, 7, 14, 21, 29, 47, 60, 75 and 102 

Sampling method Per system and label type, a single sample was collected at each 

sampling interval 

Method of collection of CO2 and organic 

volatile compounds 

Volatiles traps were collected and/or replaced at each sampling 

interval after day 0. 

Sampling intervals/times for 

Sterility check (if used): Sterile controls were not used. 

Water level maintenance: None required 

Redox potential, dissolved oxygen and 

pH in the water layer, and redox 

potential and pH in sediment: 

Measured in treated systems collected at each sampling interval. 

Probes were placed in the water phase or just below surface for 

sediment. 

Sample storage before analysis

Water and sediment were separated and the sediment extracted the 

day of sampling. 

Water layer and sediment extract samples were stored frozen until 

analysis. Water samples were typically analyzed within one week 

and sediment extract samples within ca. 1 month; extraction and 

analysis dates were not provided. 

Storage stability experiments reportedly showed nicosulfuron to 

be stable for up to six months; however, supporting data were not 

provided. Repeat analyses of selected water layer and sediment 

extract samples conducted up to ca. 18 months after initial 

analyses found quantitatively similar product profiles. 

Other observation (if any) None. 

Data obtained from pp. 27-28, 43; Table 2, p. 51; Figures 20-21, pp. 106-107 of the study report. 

3. Analytical Procedures:

Separation of the water and sediment: The water layer was separated from the sediment by 

centrifugation, decanted and analyzed by LSC (p. 28). 

Extraction/clean up/concentration methods: Sample processing is illustrated in Figure 3 (p. 71). 

Water samples were filtered (0.2-μm) and analyzed directly using LSC and HPLC (pp. 28-29). 

Sediment was extracted three times with acetone:0.1M ammonium carbonate (4:1, v:v; 160 mL; p. 

29). For each extraction, the sample and extraction solvent were shaken for 30 minutes, then 

centrifuged. Extracts were combined and a subsample was concentrated to near dryness by rotary 

evaporation. Resulting residues were reconstituted in acetone, filtered (0.45-μm), concentrated to 
Nicosulfuron (PC 129008) MRID 48354304 

Page 9 of 33 

dryness under nitrogen, then reconstituted in water:methanol (95:5, v:v) and re-filtered. Aliquots 

were analyzed using LSC and HPLC. 

Determination of unextracted residues: Extracted sediment was air-dried, homogenized using 

mortar and pestle, then analyzed by LSC following combustion (p. 29). Oxidizer efficiency was 

reported as 95-105% (p. 30). 

Determination of volatile compounds: Trapping solutions were analyzed using LSC (p. 28). 

Total radioactivity measurement: Total [14C]residues were determined by summing the 

concentrations of residues measured in the water layer, sediment extracts, extracted sediment and 

trapping solutions (pp. 32-33). 

Derivatization method A derivatization method was not employed. 

Identification and quantification of parent and transformation compounds: Water layer and 

sediment extract samples were analyzed by HPLC using a Supelco Discovery C18 column eluted 

with a gradient mobile phase of (A) 0.1% formic acid in water and (B) methanol (pp. 30-31; Figure 

4, p. 72). Column recoveries were reported as "approximately 90-110%"; HPLC results were not 

corrected for column recovery (p. 38). 

Identifications of parent compound and a major transformation product were confirmed using the 

water layer from the high dose (10x) pyridine label treated silt loam (Estany de Banyoles) system 

(pp. 29, 32, 41-42). An aliquot of the water layer was concentrated under nitrogen, filtered (0.45-

μm, then 0.2-μm), and analyzed using LC/MS/MS with electrospray ionization in positive ion mode 

(p. 32). 

Detection limits (LOD, LOQ) for the parent and transformation products: Limits of detection 

(LOD) and quantitation (LOQ) are summarized in Table 7. 

Table 7. Limits of Detection (LOD) and Quantitation (LOQ), Expressed as Percentage of the 

Applied Radioactivity 

Sample Type LOD LOQ 

HPLC analyses 

Aqueous 0.22-0.25 0.87-0.96 

Organic 0.00030-0.00071 0.0012-0.0027 

LSC analyses 

KOH trap 0.023-0.026 0.085-0.094 

Ethylene glycol trap 0.0088-0.0097 0.034-0.037 

Aqueous phase 0.056-0.062 0.22-0.24 

Organic extracts 0.35-0.39 1.4-1.5 

Soil combustions 0.098-0.11 0.35-0.39 

Data obtained from Table 3, p. 52 of the study report. 
Nicosulfuron (PC 129008) MRID 48354304 

Page 10 of 33 

II. Results and Discussion 

A. Findings: 

Total mass balances and distribution of radioactivity are presented in Tables 8a, 8b, 8c, and 8d. 

The incubation temperature and flood level were reportedly maintained throughout the experiment, 

except on one occasion when the incubation temperature exceeded 20 ± 2°C (maximum 26.3°C) for 

approximately 5 hours; the specific interval the deviation occurred was not reported (p. 36). At 

study termination in the treated silt loam (Estany de Banyoles) system, dissolved oxygen, redox 

potentials and pH in the water layer were 5.83-5.85 mg/L, +213 to +249 mV, and 7.17-7.34, 

respectively, with redox potentials and pH in the sediment of +215 to +248 mV and 7.48 (n = 2), 

respectively (Table 4A, p. 53; Table 4C, p. 54). At study termination in the treated sand (Golden 

Lake) system, dissolved oxygen, redox potentials and pH in the water layer were 5.50 mg/L (n = 2), 

+132.5 to +142.5 mV, and 8.43-8.51, respectively, with redox potentials and pH in the sediment of 

+133.4 to +151.4 mV and 7.62-8.02, respectively (Table 5A, p. 55; Table 5C, p. 56). The 

physical/chemical properties in the treated systems were comparable to those measured in untreated 

control systems (Tables 4A-5D, pp. 53-56). Sediments were viable at initiation and termination (p. 

37). 

Overall [14C]residue recoveries for pyridine- and pyrimidine-label treated systems averaged 102.0 

3.6% (range 97.8-106.6%) and 97.9 ± 4.1% (range 93.0-107.3%) of the applied, respectively, for 

the silt loam sediment system and 99.2  3.7% (range 94.5-105.4%) and 100.5 ± 3.7% (range 94.8-

105.6%), respectively, for the sand sediment system (Tables 6-7, pp. 57-60; DER Attachment 2). 

Recoveries of total residues did not decrease over time. 
Table 8a. Transformation of [Pyridine-2-14C]Nicosulfuron, Expressed as Percentage of the 

Applied Radioactivity, in Aerobic Lake Water-Silt Loam Sediment

Compound Sampling Intervals (days posttreatment) 

0 3 7 14 21 31 45 59 75 102 

Nicosulfuron 

(DPX-V9360) 101.3 94.3 93.5 94.0 91.8 81.6 70.7 67.2 53.4 42.1 

IN-37740 0 0 0 4.4 7.2 13.1 17.5 24.4 26.4 29.1 

IN-V9367 0 0 0 0 0 0 2.4 3.1 3.4 5.3 

IN-77799 0 0 0 0 0 0 1.0 2.3 1.9 2.8 

IN-HYY21 0 0 0 0 0 0 0 0 0 0.8 

Unknowns1 0.6 3.4 4.0 2.8 3.1 5.1 2.6 4.4 8.2 8.7 

Extracted residues 19.5 25.2 23.7 24.6 25.6 25.1 23.9 27.4 23.2 26.1 

Nonextractable 

residues 0 0.189 0.248 0.485 0.831 1.41 3.55 6.52 10.5 17.7 

CO2

2 -- 0.018 0.018 0.018 0.022 0.026 0.026 0.026 0.050 0.102 

Other volatile 

compounds -- 0 0 0 0 0 0 0 0 0 

Total recovery 101.9 97.8 97.8 101.8 102.9 101.2 97.8 107.9 103.8 106.6 

Data obtained from Table 6, p. 57; Table 8, p. 61 of the study report. 

-- = not analyzed. 

1 Unassigned [14C]residues with no individual unidentified HPLC peak detected at >2.1% (day 102) of applied in the 

water layer or >2.1% (day 102) in the sediment (Table 8, p. 61). 

2 All samples were connected to the same set of volatile traps. 

Table 8b. Transformation of [Pyrimidine-2-14C]Nicosulfuron, Expressed as Percentage of the 

Applied Radioactivity, in Aerobic Lake Water-Silt Loam Sediment

Compound Sampling Intervals (days posttreatment) 

0 3 7 14 21 31 45 59 75 102 

Nicosulfuron 

(DPX-V9360) 97.3 91.1 96.5 100.5 89.4 80.4 66.9 61.6 49.4 38.7 

IN-37740 0 1.7 0 5.7 8.1 13.0 17.6 23.8 24.3 22.2 

IN-77799 0 0 0 0 0 0 0.9 2.0 1.9 3.0 

IN-HYY21 0 0 0 0 0 0 0 0 0 6.6 

Unknowns1 0 0.5 0.3 0.6 1.4 1.9 7.7 6.5 7.8 10.0 

Extracted residues 20.0 20.6 21.7 25.4 24.8 23.6 25.0 26.2 22.1 24.4 

Nonextractable 

residues 0 0 0.249 0.581 0.872 1.74 3.65 7.07 9.51 17.5 

CO2

2 -- 0 0 0 0.007 0.020 0.020 0.108 0.177 0.297 

Other volatile 

compounds -- 0 0 0 0 0 0 0 0 0 

Total recovery 97.3 93.3 97.0 107.3 99.8 97.0 96.7 101.0 93.0 96.1 

Data obtained from Table 6, p. 58; Table 8, p. 62 of the study report. 

-- = not analyzed. 

1 Unassigned [14C]residues with no individual unidentified HPLC peak detected at >1.6% (day 102) of applied in the 

water layer or >2.4% (day 102) in the sediment (Table 8, p. 62). 

2 All samples were connected to the same set of volatile traps. 

 
Nicosulfuron (PC 129008) MRID 48354304 

Page 12 of 33 

Table 8c. Transformation of [Pyridine-2-14C]Nicosulfuron, Expressed as Percentage of the 

Applied Radioactivity, in Aerobic Lake Water-Sand Sediment

Compound Sampling Intervals (days posttreatment) 

0 3 7 14 21 29 47 60 75 102 

Nicosulfuron 

(DPX-V9360) 93.3 90.9 95.0 88.1 88.3 73.9 68.6 57.3 54.5 45.6 

IN-37740 0 0 0 3.1 5.9 8.5 14.1 20.3 18.7 18.7 

IN-V9367 0 0 0 0 0 0 0 3.9 3.8 4.1 

IN-77799 0 0 0 0 0 0 0 1.9 1.6 2.3 

IN-HYY21 0 0 0 0 0 0 0 0 0 3.2 

Unknowns1 3.9 1.1 4.5 1.7 2.3 6.5 7.1 5.9 8.4 5.6 

Extracted residues 14.2 18.5 17.1 19.0 22.6 20.6 23.1 24.0 25.9 21.5 

Nonextractable 

residues 1.0 3.3 5.2 4.3 8.9 5.6 8.0 9.2 14.5 19.4 

CO2

2 -- 0 0 0 0.008 0.015 0.039 0.067 0.109 0.199 

Other volatile 

compounds -- 0 0 0 0 0 0 0 0 

Total recovery 98.1 95.2 104.7 97.2 105.4 94.5 97.8 98.4 101.6 99.2 

Data obtained from Table 7, p. 59; Table 9, p. 63 of the study report. 

-- = not analyzed. 

1 Unassigned [14C]residues with no individual unidentified HPLC peak detected at >2.8% (day 75) of applied in the 

water layer or >0.9% (day 102) in the sediment (Table 9, p. 63). 

2 All samples were connected to the same set of volatile traps. 

Table 8d. Transformation of [Pyrimidine-2-14C]Nicosulfuron, Expressed as Percentage of the 

Applied Radioactivity, in Aerobic Lake Water-Sand Sediment

Compound Sampling Intervals (days posttreatment) 

0 3 7 14 21 29 47 60 75 102 

Nicosulfuron 

(DPX-V9360) 90.1 98.1 92.7 86.7 88.8 79.1 76.1 65.5 62.8 48.3 

IN-37740 0 0 0 0.6 5.6 7.9 14.2 14.2 12.2 18.7 

IN-77799 0 0 0 0 0 0 0 1.6 1.3 2.2 

IN-HYY21 0 0 0 0 0 0 0 0 2.2 2.4 

Unknowns1 3.5 1.4 6.3 4.5 2.8 4.3 4.4 10.4 8.5 7.4 

Extracted residues 14.8 17.3 19.3 20.5 25.5 23.5 25.2 26.0 24.3 22.4 

Nonextractable 

residues 1.1 1.8 6.6 4.4 7.2 8.8 8.8 10.8 9.1 20.1 

CO2

2 -- 0.003 0.010 0.016 0.033 0.082 0.199 0.198 0.373 0.668 

Other volatile 

compounds -- 0 0 0 0 0 0 0 0 0 

Total recovery 94.8 101.4 105.6 96.2 104.2 100.3 103.6 102.7 96.6 99.8 

Data obtained from Table 7, p. 60; Table 9, p. 64 of the study report. 

-- = not analyzed. 

1 Unassigned [14C]residues with no individual unidentified HPLC peak detected at >1.7% (day 75) of applied in the 

water layer or >1.1% (day 102) in the sediment (Table 9, p. 64). 

2 All samples were connected to the same set of volatile traps. 
Nicosulfuron (PC 129008) MRID 48354304 

Page 13 of 33 

B. Transformation of Parent Compound and Transformation Products: Transformation 

kinetics of the parent compound and transformation product information are summarized in Tables 

9 and 10, respectively. Degradation patterns were comparable between the foreign (Spain) silt loam 

sediment system and the domestic (North Dakota) sand sediment system. 

Based on nonlinear (SigmaPlot v. 9.0, exponential, one compartment/two parameter) regression 

analysis and using individual total system data for each sampling interval, nicosulfuron dissipated 

with reviewer-calculated half-lives of 83 days in the silt loam sediment system and 102 days in the 

sand sediment system (DER Attachment 2). 

Using first-order kinetics (one compartment/two-parameter single first-order and first-order multicompartment), the study author similarly estimated half-lives of 83 and 102 days in the silt loam 

sediment (Estany de Banyoles) and sand sediment (Golden Lake) systems, respectively, and 

estimated DT90 values of 276 and 340 days, respectively (p. 42; Figure 16, pp. 99-100; Figure 18, 

pp. 103-104). 

Table 9. Transformation Kinetics of Nicosulfuron (Combined Labels) in Aerobic WaterSediment Systems 

Total System Observed DT50

(days)1 

Observed DT90

(days)1 

Calculated 

Half-life2 

(days) 

Kinetics Model Model 

Parameters 

Catalonia, Spain lake watersilt loam sediment (20°C, 

water pH 8.2, sediment pH 

7.8)

ca. 80 >102 82.5 2-Parameter, Single 

first-order 

C0 = 101.8 

k =- 0.0084 

r

2

 = 0.9970 

North Dakota lake watersand sediment (20°C, water 

pH 8.3, sediment pH 8.2)

ca. 95 >102 101.9 2-Parameter, Single 

first-order 

C0 = 96.2 

k = -0.0068 

r

2

 = 0.9976 

1 Based on mean nicosulfuron levels at each interval and 100% application to water layer at time 0. 

2 Calculated by the reviewer using SigmaPlot v 9.0 (exponential; one compartment/two parameter) and data obtained 

from Tables 8-9, pp. 61-64 of the study report (DER Attachment 2). 

Transformation Products: One major transformation product and three minor products were 

identified by HPLC, with identification of the major product confirmed using LC/MS/MS (pp. 41-

42; Figure 1, pp. 65-66, 68-69; Figure 4, p. 72; Figures 9-14, pp. 80-96): 

 2-[[(3,4-dihydro-6-methoxy-4-oxopyrimidin-2-yl]aminocarbonyl]aminosulfonyl]-N,Ndimethyl-3-pyridinecarboxamide (IN-37740); 

 2-[(aminocarbonyl)[4-methoxy-6-(methyldioxy)-2-pyrimidinyl]amino]-N,N-dimethyl-3-

pyridinecarboxamide (IN-77799); 

 2-[[[[(aminoiminomethyl)amino]carbonyl]amino]sulfonyl]-N,N-dimethyl-3-

pyridinecarboxamide (IN-HYY21); and 

 2-(aminosulfonyl)-N,N-diemthyl-3-pyridinecarboxamide (IN-V9367). 
Nicosulfuron (PC 129008) MRID 48354304 

Page 14 of 33 

Table 10. Transformation Products of Nicosulfuron (Combined Labels) in Aerobic WaterSediment Systems1 

Transformation 

products 

Lake Water-Silt Loam Sediment Lake Water-Sand Sediment 

% Applied 

 Maximum Final Maximum Final 

IN-37740 29.1 at 102 days 29.1 at 102 days 20.3 at 60 days 18.7 at 102 days 

IN-V9367 5.3 at 102 days 5.3 at 102 days 4.1 at 102 days 4.1 at 102 days 

IN-77799 3.0 at 102 days 3.0 at 102 days 2.3 at 102 days 2.3 at 102 days 

IN-HYY21 6.6 at 102 days 6.6 at 102 days 3.2 at 102 days 3.2 at 102 days 

Data obtained from Tables 8-9, pp. 61-64 of the study report. 

1 IN-37740, IN-77799 and IN-HYY21 contained both the pyridine and pyrimidine labels, while IN-V9367 contained 

only the pyridine label. 

 

Transformation Pathway: A transformation pathway was provided by the study author and is 

illustrated below (pp. 42-43; Figure 19, p. 105). Based on the study results, nicosulfuron degrades to 

one major transformation product, IN-37740, several minor products, minor levels of CO2 and 

significant levels of sediment bound residues. The primary pathway was demethylation of the 

pyrimidinyl methoxy group to form IN-37740. Cleavage of the pyrimidine ring of IN-37740 yields 

IN-HYY21, while hydrolysis of the sulfonylurea urea bridge forms IN-V9367. Another minor 

pathway was contraction of the sulfonylurea bridge through loss of SO2 to yield IN-77799. 
Nicosulfuron (PC 129008) MRID 48354304 

Page 15 of 33 

III. Study Deficiencies and Reviewer's Comments 

1. For the sand sediment system, average mass balances determined by the reviewer differed from 

those reported by the study author. For the pyridine and pyrimidine labels, the reviewer 

determined average recoveries of 99.2  3.7% and 100.5 ± 3.7%, respectively, whereas the 

study author reported recoveries of 99.0 ± 4.3% and 100.9 ± 4.1%, respectively (p. 39; Table 7, 

pp. 59-60; DER Attachment 2). No explanation for the discrepancies could be determined. 

2. The study was conducted for an insufficient length of time. The patterns of formation and 

decline of the transformation products were not established at study termination. The major 

transformation product, IN-37740, was detected at a maximum 29.1% of the applied at study 

termination in the silt loam system, and was detected at a maximum 20.3% at 60 days in the 

sand system declining only to 18.7% at study termination (Tables 8-9, pp. 61-64). Additionally, 

all three minor products, IN-V9360, IN-77799 and HYY21, were detected at maximum 

concentrations at study termination. 

3. Nonextractable [14C]residues were detected at maximums of 17.5-20.1% of the applied at study 

termination, but were not characterized through organic matter fractionation (Tables 6-7, pp. 57-

60). 

4. Per treatment type (water-sediment system, label), a single treated sample was collected at each 

sampling interval for analysis. Duplicate replicate samples should be taken at each sampling 

interval for analysis to allow for a better assessment of the study results. 

5. The pesticide use histories for the source sites for the test waters and sediments were not 

reported. The water and sediment were not analyzed for pesticides to establish that they were 

not contaminated prior to treatment. 

6. The length of storage and storage conditions of the collected water and sediment prior to 

preparation of test systems for pre-treatment acclimation was not adequately addressed. Current 

OCSPP guidelines specify if storage is necessary, sediment and water should be sieved and 

stored together, water-logged (6-10 cm water layer), in the dark, at 4 ± 2°C for a maximum of 4 

weeks. Water and sediment were reportedly used within approximately one month after 

collection; however, specific intervals/dates were not provided (p. 36). Sediment was reported 

as stored at ca. 4°C in darkness (p. 23). Storage conditions of the water were not described. 

7. The amount of sediment utilized per test system was 40 g (dry wt.) for these experiments; 

sediment layer depths were not reported (p. 24). Current OCSPP guidelines recommend a 

minimum amount of 50 g of sediment (dry wt. basis) per incubation vessel is utilized, with a 

sediment layer depth of 2.5 ± 0.5 cm. The water:sediment volume ratio of the test systems was 

4:1, within OCSPP guidelines. 

8. All samples from a given treatment were connected in series to the same set of volatile traps (p. 

24). The reported concentration of CO2 was adjusted based on the number of samples in the 

chamber at the time of sampling (p. 33). It is preferred that sample vessels be connected to 

individual volatile traps so that more precise material balances for each sample can be 

calculated. 
Nicosulfuron (PC 129008) MRID 48354304 

Page 16 of 33 

IV. References 

1. U.S. Environmental Protection Agency. 2008. Fate, Transport and Transformation Test -

Guidelines, OPPTS 835.4300, Aerobic Aquatic Metabolism. Office of Prevention, Pesticides 

and Toxic Substances, Washington, DC. EPA 712-C-08-018. 

2. U.S. Environmental Protection Agency. 1982. Pesticide Assessment Guidelines, Subdivision N, 

Chemistry: Environmental Fate, Section 162-4, Aerobic Aquatic Metabolism Studies. Office of 

Pesticide and Toxic Substances, Washington, DC. EPA 540/9-82-021. 
Nicosulfuron (PC 129008) MRID 48354304 

Page 17 of 33 

DER ATTACHMENT 1. Nicosulfuron and Its Environmental Transformation Products. A

Code Name/ Synonym Chemical Name Chemical Structure Study Type MRID Max

%A

PARENT

Nicosulfuron  (DPX-V9360) 

IUPAC: 2-[(4,6-Dimethoxypyrimidin-2-ylcarbamoyl)sulfamoyl]-N,Ndimethylnicotinamide CAS: 2-[[[[(4,6-Dimethoxy-2-pyrimidinyl)amino]carbonyl]amino]sulfonyl]-N,N-dimethyl-3-pyridinecarboxamide CAS No.: 111991-09-4 Formula: C15

H18

N6O6S 

MW: 410.411 g/molSMILES: c1(c(nccc1)S(=O)(=O)NC(=O)Nc2nc(cc(n2)OC)OC)C(=O)N(C)C

S

O

O

O

O CH3O CH3

NN

NH

NH O

N

H3C

H3C

N

835.4300 

Aerobic aquatic 

metabolism 

48354304 

Lake 

loam 

101.3

Lake w

sedime

(

MAJOR (>10%) TRANSFORMATION PRODUCTS 

IN-37740 CAS: 2-[[(3,4-Dihydro-6-methoxy4-oxopyrimidin-2-

yl]aminocarbonyl]aminosulfonyl]-N,N-dimethyl-3-pyridinecarboxamideFormula: C14

H16

N6O6S 

MW: 396.38 g/molSMILES: c1(c(nccc1)S(=O)(=O)NC(N/C2=N/C(=C\C(N2)=O)OC)=O)C(N(C)C)=O

835.4300 

Aerobic aquatic 

metabolism 

48354304 

Lake 

loam 

29.1% 

Lake w

sedime

(6

Pyridine sulfonamide  (IN-V9367) 

CAS: 2-(Aminosulfonyl)-N,Ndimethyl-3-pyridinecarboxamide CAS No.: 112006-75-4 

835.4300 

Aerobic aquatic 

metabolism 

48354304 

Lake 

loam 

5.3% 
Nicosulfuron (PC 129008) MRID 48354304 

Page 18 of 33 

Code Name/ Synonym Chemical Name Chemical Structure Study Type MRID Max

%A

Formula: C8H11

N3O3S 

MW: 229.259 g/mol

SMILES: c1(cccnc1S(=O)(=O)N)C(=O)N(C)C 

Lake w

sedim

(1

Unextracted 

residues 

NA NA 835.4300 Aerobic aquatic 

metabolism 

48354304 

Lake 

loam 

17.7% 

Lake w

sedime

(1

MINOR (<10%) TRANSFORMATION PRODUCTS

IN-77799 (DPX-V9360 Ipso precursor)

CAS: 2-[(Aminocarbonyl)[4-methoxy-6-(methyldioxy)-2-pyrimidinyl]amino]-N,N-dimethyl3-pyridinecarboxamide

Formula: C15

H18

N6O4

MW: 346.34 g/molSMILES: NC(N(c1nc(cc(n1)OC)OC)c2ncccc2C(N(C)C)=O)=O

835.4300 

Aerobic aquatic 

metabolism 

48354304 

Lake 

loam 

3.0% 

Lake w

sedim

(1

IN-HYY21 CAS: 2-

[[[[(Aminoiminomethyl)amino]carbonyl]amino]sulfonyl]-N,Ndimethyl-3-pyridinecarboxamideFormula: C10

H14

N6O4S 

MW: 314.33 g/molSMILES: c1(c(nccc1)S(=O)(=O)NC(NC(=N)N)=O)C(N(C)C)=O

835.4300 

Aerobic aquatic 

metabolism 

48354304 

Lake 

loam 

6.6% 

Lake w

sedim

(1
Nicosulfuron (PC 129008) MRID 48354304 

Page 19 of 33 

Code Name/ Synonym Chemical Name Chemical Structure Study Type MRID Max

%A

Carbon dioxide Carbon dioxide 

Formula: CO2

MW: 44 g/molSMILES: C(=O)=O 

835.4300 

Aerobic aquatic 

metabolism 

48354304 

Lake 

loam 

0.297% 

Lake w

sed

0.668% 

REFERENCE COMPOUNDS NOT IDENTIFIED 

IN-74427 (DPX-V9360 Ipso product)

CAS: 2-[(4,6-Dimethoxy-2-pyrimidinyl)-amino]-N,N-dimethyl3-pyridinecarboxamideFormula:

C14

H17

N5O3

MW: 303.323 g/molSMILES: c1(c(nccc1)Nc2nc(cc(n2)OC)OC)C(N(C)C)=O 

835.4300 

Aerobic aquatic 

metabolism 

48354304 

O,O-Bisdesmethyl pyrimidine amine (IN-H1043) 

CAS: 2-Amino-6-hydroxy-4(1H)-pyrimidinone CAS No.: 56-09-7Formula: C4H5N3O2

MW: 127.103 g/mol

SMILES: n1c(nc(cc1O)O)N 

835.4300 

Aerobic aquatic 

metabolism 

48354304 

N-Desmethyl DPXV9360 (IN-W9807) 

CAS: 2-[[[[(4,6-Dimethoxypyrimidin-2yl)amino]carbonyl]-amino]sulfonyl]-N-methyl-3-pyridinecarboxamideFormula: C14

H16

N6O6S 

MW: 396.384 g/molSMILES: c1(c(nccc1)S(=O)(=O)NC(Nc2nc(cc(n2)OC)OC)=O)C(NC)=O

835.4300 

Aerobic aquatic 

metabolism 

48354304 
Nicosulfuron (PC 129008) MRID 48354304 

Page 20 of 33 

Code Name/ Synonym Chemical Name Chemical Structure Study Type MRID Max

%A

O,O-Desmethyl pyrimidine amine (IN-H9235) 

CAS: 2-Amino-4-hydroxy-6-methoxypyrimidineFormula: C5H7N3O2

MW: 141.130 g/mol

SMILES: c1c(nc(nc1OC)N)O

835.4300 

Aerobic aquatic 

metabolism 

48354304 

Pyrimidine amine (IN-J0290) 

CAS: 4,6-Dimethoxy-2-pyrimidinamine CAS No.: 36315-01-2 Formula: C6H9N3O2

MW: 155.15 g/molSMILES: Nc1nc(cc(n1)OC)OC 

835.4300 

Aerobic aquatic 

metabolism 

48354304 

Pyridine saccharin 

analog 

 (IN-64554) 

CAS: Isothiaxolo[5,4-b]pyridin3(2H)-one,1,1-dioxide CAS No.: 138417-40-0 Formula: C6H4N2O3S 

MW: 184.17 g/molSMILES: c12cccnc1S(NC2=O)(=O)=O 

835.4300 

Aerobic aquatic 

metabolism 

48354304 

IN-GDC42 CAS: 2-

[[[[(Aminocarbonyl)amino]carbonyl]amino]sulfonyl]-N,N-dimethyl-3-pyridinecarboxamideFormula: C10

H13

N5O5S 

MW: 315.309 g/molSMILES: c1(ncccc1C(=O)N(C)C)S(NC(NC(N)=O)=O)(=O)=O

835.4300 

Aerobic aquatic 

metabolism 

48354304 
Nicosulfuron (PC 129008) MRID 48354304 

Page 21 of 33 

Code Name/ Synonym Chemical Name Chemical Structure Study Type MRID Max

%A

IN-69188 CAS: 1-(4,6-Dimethoxypyrimidin2-yl)pyrido[2,3-d]pyrimidine-2,4-

dioneFormula: C10

H13

N5O5S 

MW: 315.309 g/molSMILES: c1(ncccc1C(=O)N(C)C)S(NC(NC(N)=O)=O)(=O)=O

835.4300 

Aerobic aquatic 

metabolism 

48354304 

A AR means “applied radioactivity”. MW means “molecular weight”. NA means "not applicable". 1 Expressed as percentage of recovered radioactivity.
Nicosulfuron (PC 129008) MRID 48354304 

Page 22 of 33 

Attachment 2: Statistics Spreadsheets and Graphs 

Chemical: Nicosulfuron 

MRID: 48354304 PC: 129008 Guideline: 835.4300 Silt Loam (Estany de Banyoles) systems: Total system, labels combined Linear Nonlinear Half-life (days): 78.0 Half-life (days): 82.5 r2 : 0.9970Days Nicosulfuron (DPX-V9360) Posttreatment 

(% of applied) 

Ln (% 

applied) 

0 101.3 4.61810 97.3 4.57783 94.3 4.54653 91.1 4.51207 93.5 4.53807 96.5 4.5695

14 94.0 4.543314 100.5 4.610221 91.8 4.519621 89.4 4.493131 81.6 4.401831 80.4 4.387045 70.7 4.258445 66.9 4.203259 67.2 4.207759 61.6 4.120775 53.4 3.977875 49.4 3.9000

102 42.1 3.7400102 38.7 3.6558
Nicosulfuron (PC 129008) MRID 48354304 

Page 23 of 33 

Data obtained from Table 8, pp. 61-62 of the study report. 

SUMMARY OUTPUT 

Regression Statistics 

Multiple R 0.98236497 R Square 0.965040935 Adjusted R Square 0.963098765 Standard Error 0.057612993 Observations 20 ANOVA 

 df SS MS F 

Significance 

F 

Regression 1 1.649298636 1.649298636 496.8879111 1.4698E-14Residual 18 0.059746625 0.003319257Total 19 1.70904526 

 Coefficients 

Standard 

Error t Stat P-value Lower 95% Upper 95% Lower 

Intercept 4.636218892 0.019194999 241.5326505 4.68832E-33 4.595891696 4.676546088 4.5958X Variable 1 

-

0.008885003 0.000398592 -22.29098273 1.4698E-14

-

0.009722413

-

0.008047592

0.0097
Nicosulfuron (PC 129008) MRID 48354304 

Page 24 of 33 

Chemical: Nicosulfuron 

MRID: 48354304 PC: 129008 Guideline: 835.4300 Sand (Golden Lake) systems: Total system, labels combined Linear Nonlinear Half-life (days): 100.0 Half-life (days): 101.9 r2 : 0.9976Days Nicosulfuron (DPX-V9360) Posttreatment 

(% of applied) 

Ln (% 

applied) 

0 93.3 4.53580 90.1 4.50093 90.9 4.50983 98.1 4.58607 95.0 4.55397 92.7 4.5294

14 88.1 4.478514 86.7 4.462521 88.3 4.480721 88.8 4.486429 73.9 4.302729 79.1 4.370747 68.6 4.228347 76.1 4.332060 57.3 4.048360 65.5 4.182175 54.5 3.998275 62.8 4.1400

102 45.6 3.8199102 48.3 3.8774

Data obtained from Table 9, pp. 63-64 of the study report. SUMMARY OUTPUT 
Nicosulfuron (PC 129008) MRID 48354304 

Page 25 of 33 

Regression Statistics 

Multiple R 0.974304231 R Square 0.949268735 Adjusted R Square 0.946450332 Standard Error 0.054907877 Observations 20 ANOVA 

 df SS MS F 

Significance 

F 

Regression 1 1.015442404 1.015442404 336.8107893 4.22579E-13Residual 18 0.054267749 0.003014875Total 19 1.069710153 

 Coefficients 

Standard 

Error t Stat P-value Lower 95% Upper 95% Lower 

Intercept 4.56943354 0.018268529 250.1259751 2.4992E-33 4.531052785 4.607814294 4.5310X Variable 1 

-

0.006934738 0.000377865 -18.35240554 4.22579E-13

-

0.007728603

-

0.006140872

0.0077
Nicosulfuron (PC 129008) MRID 48354304 

Page 26 of 33 

Chemical: Nicosulfuron 

MRID: 

48354304 

PC: 129008 

Guideline: 835.4300 

Silt Loam (Estany de Banyoles) systems: Total system, labels combined 

Nonlinear Regression 

Data Source: Data 1 in 129008 48354304 835.4300 Silt loam.JNB 

Equation: Single, 2 Parameter 

R Rsqr Adj Rsqr Standard Error of Estimate

0.9985 0.9970 0.9967 4.6163 

 Coefficient Std. Error t P VIF 

a 101.7947 1.7407 58.4806 <0.0001 1.7757 

b 0.0084 0.0005 16.1711 <0.0001 1.7757 

Analysis of Variance: 

 DF SS MS 

Regression 2 129416.6872 64708.3436 

Residual 18 383.5828 21.3102 

Total 20 129800.2700 6490.0135 

Statistical Tests:

PRESS 470.7657 

Durbin-Watson Statistic 0.7604 Failed 

Normality Test Passed (P = 0.9919) 

K-S Statistic = 0.0938 Significance Level = 0.9919 

Constant Variance Test Passed (P = 0.7000) 

Power of performed test with alpha = 0.0500: 1.0000

Regression Diagnostics:

Row Predicted Residual Std. Res. Stud. Res. Stud. Del. Res. 

1 101.7947 -0.4947 -0.1072 -0.1157 -0.1125 

2 101.7947 -4.4947 -0.9737 -1.0513 -1.0545 

3 99.2758 -4.9758 -1.0779 -1.1491 -1.1601 

4 99.2758 -8.1758 -1.7711 -1.8881 -2.0490< 

5 96.0139 -2.5139 -0.5446 -0.5730 -0.5620 

6 96.0139 0.4861 0.1053 0.1108 0.1077 

7 90.5614 3.4386 0.7449 0.7723 0.7633 

8 90.5614 9.9386 2.1529 2.2322< 2.5509< 

9 85.4186 6.3814 1.3824 1.4231 1.4681 

10 85.4186 3.9814 0.8625 0.8879 0.8824 

11 78.5742 3.0258 0.6555 0.6740 0.6634 

12 78.5742 1.8258 0.3955 0.4067 0.3971 

Chemical: Nicosulfuron 

MRID: 
Nicosulfuron (PC 129008) MRID 48354304 

Page 27 of 33 

48354304 

PC: 129008 

Guideline: 835.4300 

Silt Loam (Estany de Banyoles) systems: Total system, labels combined 

13 69.9033 0.7967 0.1726 0.1790 0.1741 

14 69.9033 -3.0033 -0.6506 -0.6748 -0.6642 

15 62.1894 5.0106 1.0854 1.1420 1.1523 

16 62.1894 -0.5894 -0.1277 -0.1343 -0.1306 

17 54.4101 -1.0101 -0.2188 -0.2343 -0.2280 

18 54.4101 -5.0101 -1.0853 -1.1619 -1.1740 

19 43.4253 -1.3253 -0.2871 -0.3144 -0.3064 

20 43.4253 -4.7253 -1.0236 -1.1209 -1.1295 

Influence Diagnostics: 

Row Cook's Dist Leverage DFFITS 

1 0.0011 0.1422 -0.0458 

2 0.0916 0.1422 -0.4293 

3 0.0902 0.1201 -0.4287 

4 0.2434 0.1201 -0.7572 

5 0.0176 0.0968 -0.1840 

6 0.0007 0.0968 0.0353 

7 0.0224 0.0698 0.2090 

8 0.1868 0.0698 0.6985 

9 0.0606 0.0564 0.3591 

10 0.0236 0.0564 0.2158 

11 0.0130 0.0541 0.1587 

12 0.0047 0.0541 0.0950 

13 0.0012 0.0704 0.0479 

14 0.0173 0.0704 -0.1829 

15 0.0697 0.0966 0.3768 

16 0.0010 0.0966 -0.0427 

17 0.0040 0.1274 -0.0871 

18 0.0986 0.1274 -0.4487 

19 0.0098 0.1661 -0.1367 

20 0.1251 0.1661 -0.5041 

95% Confidence:

Row Predicted Regr. 5% Regr. 95% Pop. 5% Pop. 95% 

1 101.7947 98.1377 105.4517 91.4297 112.1597 

2 101.7947 98.1377 105.4517 91.4297 112.1597 

3 99.2758 95.9141 102.6374 89.0112 109.5403 

4 99.2758 95.9141 102.6374 89.0112 109.5403 

5 96.0139 92.9966 99.0313 85.8569 106.1709 

6 96.0139 92.9966 99.0313 85.8569 106.1709 

7 90.5614 88.0000 93.1229 80.5304 100.5925 

8 90.5614 88.0000 93.1229 80.5304 100.5925 

9 85.4186 83.1143 87.7229 75.4501 95.3870 

10 85.4186 83.1143 87.7229 75.4501 95.3870 

11 78.5742 76.3177 80.8306 68.6167 88.5317 

12 78.5742 76.3177 80.8306 68.6167 88.5317 

13 69.9033 67.3292 72.4775 59.8691 79.9376 

14 69.9033 67.3292 72.4775 59.8691 79.9376 

15 62.1894 59.1753 65.2034 52.0333 72.3454 

16 62.1894 59.1753 65.2034 52.0333 72.3454 

Chemical: Nicosulfuron 

MRID: 

48354304 

PC: 129008 
Nicosulfuron (PC 129008) MRID 48354304 

Page 28 of 33 

Guideline: 835.4300 

Silt Loam (Estany de Banyoles) systems: Total system, labels combined 

17 54.4101 50.9480 57.8723 44.1122 64.7080 

18 54.4101 50.9480 57.8723 44.1122 64.7080 

19 43.4253 39.4728 47.3779 32.9524 53.8983 

20 43.4253 39.4728 47.3779 32.9524 53.8983 

Fit Equation Description:

[Variables] 

x = col(1) 

y = col(2) 

reciprocal_y = 1/abs(y) 

reciprocal_ysquare = 1/y^2 

'Automatic Initial Parameter Estimate Functions 

F(q)=if(size(x)>1, if(total(abs(y))>0, ape(x,log(abs(y)),1,0,1), -306), 0) 

asign(q)=if(mean(q)>=0,1,-1) 

[Parameters] 

a = if(F(0)[1]< 307, if(F(0)[1]>-307, asign(y)*10^F(0)[1], asign(y)*10^(-307)), asign(y)*10^307) ''Auto {{previous: 

101.795}} 

b = if(x50(x,y)-min(x)=0, 1, -ln(.5)/(x50(x,y)-min(x))) ''Auto {{previous: 0.00835211}} 

[Equation] 

f = a*exp(-b*x) 

fit f to y 

''fit f to y with weight reciprocal_y 

''fit f to y with weight reciprocal_ysquare 

[Constraints] 

b>0 

[Options] 

tolerance=1e-10 

stepsize=1 

iterations=200 

Number of Iterations Performed = 6 
Nicosulfuron (PC 129008) MRID 48354304 

Page 29 of 33 
Nicosulfuron (PC 129008) MRID 48354304 

Page 30 of 33 

Chemical: Nicosulfuron 

MRID: 48354304 

PC: 129008 

Guideline: 835.4300 

Sand (Golden Lake) systems: Total system, labels combined 

Nonlinear Regression 

Data Source: Data 1 in 129008 48354304 835.4300 Sand.JNB 

Equation: Single, 2 Parameter 

R Rsqr Adj Rsqr Standard Error of Estimate

0.9988 0.9976 0.9974 4.0320 

 Coefficient Std. Error t P VIF 

a 96.1846 1.4840 64.8142 <0.0001 1.8173 

b 0.0068 0.0004 15.6654 <0.0001 1.8173 

Analysis of Variance: 

 DF SS MS 

Regression 2 124110.8779 62055.4390 

Residual 18 292.6321 16.2573 

Total 20 124403.5100 6220.1755 

Statistical Tests:

PRESS 358.6015 

Durbin-Watson Statistic 2.3731 Passed 

Normality Test Passed (P = 0.9866) 

K-S Statistic = 0.0980 Significance Level = 0.9866 

Constant Variance Test Passed (P = 0.7576) 

Power of performed test with alpha = 0.0500: 1.0000

Regression Diagnostics:

Row Predicted Residual Std. Res. Stud. Res. Stud. Del. Res. 

1 96.1846 -2.8846 -0.7154 -0.7694 -0.7604 

2 96.1846 -6.0846 -1.5091 -1.6230 -1.7071 

3 94.2475 -3.3475 -0.8302 -0.8832 -0.8775 

4 94.2475 3.8525 0.9555 1.0164 1.0174 

5 91.7252 3.2748 0.8122 0.8540 0.8473 

6 91.7252 0.9748 0.2418 0.2542 0.2475 

7 87.4726 0.6274 0.1556 0.1614 0.1570 

8 87.4726 -0.7726 -0.1916 -0.1987 -0.1933 

9 83.4171 4.8829 1.2110 1.2469 1.2678 

10 83.4171 5.3829 1.3350 1.3746 1.4120 

11 79.0120 -5.1120 -1.2678 -1.3023 -1.3298 

12 79.0120 0.0880 0.0218 0.0224 0.0218 

13 69.9324 -1.3324 -0.3304 -0.3426 -0.3340 

Chemical: Nicosulfuron 
Nicosulfuron (PC 129008) MRID 48354304 

Page 31 of 33 

MRID: 48354304 

PC: 129008 

Guideline: 835.4300 

Sand (Golden Lake) systems: Total system, labels combined 

14 69.9324 6.1676 1.5297 1.5857 1.6615 

15 64.0309 -6.7309 -1.6694 -1.7544 -1.8726 

16 64.0309 1.4691 0.3644 0.3829 0.3737 

17 57.8377 -3.3377 -0.8278 -0.8863 -0.8807 

18 57.8377 4.9623 1.2307 1.3177 1.3472 

19 48.1602 -2.5602 -0.6350 -0.7020 -0.6917 

20 48.1602 0.1398 0.0347 0.0383 0.0372 

Influence Diagnostics: 

Row Cook's Dist Leverage DFFITS 

1 0.0464 0.1355 -0.3010 

2 0.2064 0.1355 -0.6757 

3 0.0513 0.1163 -0.3183 

4 0.0680 0.1163 0.3691 

5 0.0385 0.0955 0.2753 

6 0.0034 0.0955 0.0804 

7 0.0010 0.0703 0.0432 

8 0.0015 0.0703 -0.0532 

9 0.0468 0.0567 0.3109 

10 0.0568 0.0567 0.3463 

11 0.0467 0.0522 -0.3120 

12 1.3838E-005 0.0522 0.0051 

13 0.0044 0.0695 -0.0913 

14 0.0939 0.0695 0.4540 

15 0.1609 0.0946 -0.6054 

16 0.0077 0.0946 0.1208 

17 0.0575 0.1276 -0.3369 

18 0.1270 0.1276 0.5153 

19 0.0547 0.1818 -0.3260 

20 0.0002 0.1818 0.0176 

95% Confidence:

Row Predicted Regr. 5% Regr. 95% Pop. 5% Pop. 95% 

1 96.1846 93.0668 99.3024 87.1581 105.2112 

2 96.1846 93.0668 99.3024 87.1581 105.2112 

3 94.2475 91.3587 97.1363 85.2975 103.1975 

4 94.2475 91.3587 97.1363 85.2975 103.1975 

5 91.7252 89.1075 94.3429 82.8590 100.5915 

6 91.7252 89.1075 94.3429 82.8590 100.5915 

7 87.4726 85.2266 89.7185 78.7089 96.2363 

8 87.4726 85.2266 89.7185 78.7089 96.2363 

9 83.4171 81.3993 85.4349 74.7091 92.1251 

10 83.4171 81.3993 85.4349 74.7091 92.1251 

11 79.0120 77.0771 80.9469 70.3228 87.7011 

12 79.0120 77.0771 80.9469 70.3228 87.7011 

13 69.9324 67.6994 72.1653 61.1720 78.6927 

14 69.9324 67.6994 72.1653 61.1720 78.6927 

15 64.0309 61.4251 66.6367 55.1682 72.8937 

16 64.0309 61.4251 66.6367 55.1682 72.8937 

17 57.8377 54.8112 60.8642 48.8423 66.8331 

18 57.8377 54.8112 60.8642 48.8423 66.8331 

Chemical: Nicosulfuron 

MRID: 48354304 

PC: 129008 
Nicosulfuron (PC 129008) MRID 48354304 

Page 32 of 33 

Guideline: 835.4300 

Sand (Golden Lake) systems: Total system, labels combined 

19 48.1602 44.5486 51.7719 38.9515 57.3690 

20 48.1602 44.5486 51.7719 38.9515 57.3690 

Fit Equation Description:

[Variables] 

x = col(1) 

y = col(2) 

reciprocal_y = 1/abs(y) 

reciprocal_ysquare = 1/y^2 

'Automatic Initial Parameter Estimate Functions 

F(q)=if(size(x)>1, if(total(abs(y))>0, ape(x,log(abs(y)),1,0,1), -306), 0) 

asign(q)=if(mean(q)>=0,1,-1) 

[Parameters] 

a = if(F(0)[1]< 307, if(F(0)[1]>-307, asign(y)*10^F(0)[1], asign(y)*10^(-307)), asign(y)*10^307) ''Auto {{previous: 

96.1846}} 

b = if(x50(x,y)-min(x)=0, 1, -ln(.5)/(x50(x,y)-min(x))) ''Auto {{previous: 0.00678172}} 

[Equation] 

f = a*exp(-b*x) 

fit f to y 

''fit f to y with weight reciprocal_y 

''fit f to y with weight reciprocal_ysquare 

[Constraints] 

b>0 

[Options] 

tolerance=1e-10 

stepsize=1 

iterations=200 

Number of Iterations Performed = 7 
Nicosulfuron (PC 129008) MRID 48354304 

Page 33 of 33