2

1 EXECUTIVE SUMMARY

This memo summarizes the estimated drinking water concentrations (EDWCs) of 

flupyradifurone (PC Code 122304, 2(5H-(furanone), 4-{{(6-chloro-3-pyridinyl)methyl](2,2-

difluoroethyl)amino]-, also known as BYI 02960) and residues of concern in surface water and in 

groundwater in support of the proposed Section 3 new chemical registration of flupyradifurone 

as an insecticide on a variety of agricultural crops and crop groups. Residues of concern 

include:

• difluoroacetic acid (DFA),

• BYI 02960-succinamide (M48), 

• BYI 02960-azabicyclosuccinamide (M47), and 

• Unextracted residues.

EDWCs were calculated for total toxic residues consisting of 1) parent plus M47 plus M48 plus 

unextracted residues (referred to as “TTR-UN”), and 2) parent plus M47 plus M48 (referred to 

as “TTR”). EDWCs were also calculated for DFA alone. The structures of M47 and M48 are 

similar to that of the parent, and may possess a similar mode of action. The structure of DFA is 

very different from that of the parent, and its mode of action and observed toxicity patterns are 

also different.

The EDWCs for both surface water and groundwater recommended for use in HED’s human 

health dietary risk assessment are summarized in Table 1 and 2. The national all-agriculture

Percent Cropped Area (PCA) adjustment factor of 0.91 was assumed for surface water, as 

flupyradifurone has proposed uses on a variety of agricultural crops. If these EDWCs result in 

risk concerns, they can be refined1

. The main uncertainty in the EDWCs is that a maximum 

annual application rate was not provided on the label for any use pattern. Use rates were 

provided on a seasonal basis. Some proposed uses could entail multiple seasons per year. If 

two and three seasons per year are assumed, EDWCs could be two to three fold higher than 

those estimated based upon one season per year. Some crops are expected to have up to three

seasons per year in some areas (USEPA, 2009b).

Table 1. Tier I EDWCs for residues of flupyradifurone plus M47 plus M48 plus unextracted residues.

1

Source of Drinking Water (Model)

TTR-UN concentration in drinking water (μg/L)

Acute Annual Average or Post 

Breakthrough Average

Surface Water (Modified Tier 1 Rice Model) 112 112

Surface water (PRZM/EXAMS)

46.1 ( 1 season)

47.7 (2 seasons)

52.5 (3 seasons)

13.9 ( 1 season)

20.1 (2 seasons)

22.3 (3 seasons)

Groundwater (PRZM-GW)

117 (1 season)

23.8 (2 seasons)

352 (3 seasons)

102 (1 season)

208 (2 seasons)

307 (3 seasons)

* All values reflect residues of flupyradifurone plus M47 plus M48 plus unextracted residues. 1

Refinements can be made to get lower EDWCs Tier II modeling could be conducted to determine EDWC in 

groundwater.

 1 Tier II modeling could be conducted to determine EDWC in groundwater.
3

Table 2. Tier I EDWCs for residues of Difluoroacetic acid (DFA).

1

Source of Drinking Water (Model)

DFA concentration in drinking water (μg/L)

Acute Annual Average or Post 

Breakthrough Average

Surface Water (Modified Tier 1 Rice Model) 43 43

Surface water (PRZM/EXAMS)

7.35 ( 1 season)

8.18 (2 seasons)

9.71 (3 seasons)

4.34 ( 1 season)

5.12 (2 seasons)

7.74 (3 seasons)

Groundwater (PRZM-GW)

51.7 (1 season)

105 (2 seasons)

152 (3 seasons)

36.0 (1 season)

76.2 (2 seasons)

114 (3 seasons) 1

Refinements can be made to get lower EDWCs. Tier II modeling could be conducted to determine EDWC in 

groundwater. 

2 CHEMICAL CLASS AND MODE OF ACTION

Flupyradifurone belongs to the butenolide chemical class of insecticides; the compound is taken 

up by plants and systemically distributed. The insecticidal activity of flupyradifurone is similar to 

the neonicotinoids, presumably due to its agonist activity in nicotinic acetylcholine receptors, 

making it a member of the Insecticide Resistance Action Committee (IRAC) Group 4 insecticide 

class (IRAC, 2012).

3 PROPOSED USES

The registrant (Bayer CropScience) is seeking registration of several uses (described in Table 3) 

of flupyradifurone on two labels: 

• SivantoTM 200 SL (Sivanto) for use as a foliar and soil drench application to various 

agricultural crops, and

• BYI 02960 480 FS (BYI 02960), a systemic seed treatment insecticide for use on soybean 

seeds. 

Both are liquid formulations. Sivanto may be applied to agricultural crops before bloom, during 

bloom, or following bloom up to the stated pre-harvest interval (PHI). Sivanto may be applied 

via ground, airblast, aerial, or chemigation equipment. BYI 02960 may be applied to soybean 

seeds via commercial seed treatment application only. 

Most uses have the same proposed maximum single and seasonal application rates of 0.18 lbs 

active ingredient per acre (lbs a.i./A) and 0.37 lbs a.i./A per season, respectively. A few crops 

(fruiting vegetables, cucurbit vegetables, citrus fruit, small fruit and vine climbing group) have 

both proposed maximum single and seasonal application rates of 0.37 lbs a.i./A. The number of 

proposed seasonal or annual applications is not specified for any use, and retreatment intervals 

range from “not specified” to 10 days. The labels do include a maximum seasonal application

rate and thus the maximum number of applications per season may be estimated by dividing 

the maximum seasonal application rate by the maximum single application rate.
4

Table 3. Proposed Uses of Flupyradifurone

Use Site

Single App.

Rate

in lbs. a.i./A

(kg a.i./ha)

# of 

App

Seasonal 

App. Rate

lbs. a.i./A

(kg

a.i./ha)

MRI

(days) PHI (days) Geographic Restrictions Comments

Crop Group 15: 

Cereal Grains 

(except Rice)

0.09 - 0.18

(0.10 - 0.20) NS 0.365

(0.409) 7

7 forage and 

sweet corn -- foliar

21 dried grain --

Cotton 0.09 - 0.18

(0.10 - 0.20) NS 0.365(0.409) 10 14 -- foliar

Nongrass Animal 

Feeds (Forage, 

Fodder, Straw, 

Hay)

0.09 - 0.18

(0.10 - 0.20) NS 0.365

(0.409) 10

7 forage, silage, 

hay or seed of 

alfalfa

-- foliar

14 all others --

Peanut 0.09 - 0.18

(0.10 - 0.20) NS 0.365

(0.409) 10 7 -- foliar

Root Vegetables 

(except 

Sugarbeet)

0.09 - 0.18

(0.10 - 0.20) NS 0.365

(0.409) 10 7 -- foliar

Tuberous and 

Corm 

Vegetables

0.09 - 0.18

(0.10 - 0.20) NS 0.365

(0.409) 7 7 West of MS 

river

Leafy Vegetables 

(except Brassica)

0.09 - 0.18

(0.10 - 0.20) NS 0.365

(0.409) 7 1 -- foliar

Brassica (Cole) 

Leafy Vegetables

0.09 - 0.18

(0.10 - 0.20) NS 0.365

(0.409) 7 1 -- foliar
5

Use Site

Single App.

Rate

in lbs. a.i./A

(kg a.i./ha)

# of 

App

Seasonal 

App. Rate

lbs. a.i./A

(kg

a.i./ha)

MRI

(days) PHI (days) Geographic Restrictions Comments

Legume 

Vegetables 

(Succulent or 

Dried)

0.09 - 0.18

(0.10 - 0.20) NS 0.365

(0.409) 10

7 forage, leaves, 

vines, pods, 

cutting for hay or 

seed

-- foliar

21 dry soybean 

seed -- foliar

Fruiting 

Vegetables

0.09 - 0.18

(0.10 - 0.20) NS 0.365(0.409)

71 West of MS 

river foliar

0.27 – 0.37

(0.31 – 0.41) NS 0.365

(0.409) NS 45 --

soil, chemigation to root zone, injection below 

seed line, potting hole drench at transplanting, 

post-transplant drench following setting and 

covering

Cucurbit 

Vegetables

0.09 - 0.18

(0.10 - 0.20) NS 0.365(0.409)

71 West of MS 

river foliar

0.27 – 0.37

(0.31 – 0.41) NS 0.365

(0.409)

7 21 --

soil, chemigation to root zone, injection below 

seed line, potting hole drench at transplanting, 

post-transplant drench following setting and 

covering

Hop 0.09 

– 0.14

(0.10 - 0.15) NS 0.14(0.15) NS 21 -- Foliar

Citrus Fruit

0.27 – 0.37

(0.31 – 0.41) NS 0.365

(0.409)

10 30 --

Soil, chemigation into root zone through low 

pressure drip, trickle, micro-sprinkler; basal 

drench in sufficient water to move into root zone

0.09 - 0.18

(0.10 - 0.20) NS 10

1 -- foliar

Pome Fruit 0.09 

- 0.18

(0.10 - 0.20) NS 0.365

(0.409) 10 14 --

Foliar, combine with horticultural oil for early 

season applications targeting San Jose scale and 

Pear psylla

Bushberry 0.09 

- 0.18

(0.10 - 0.20) NS 0.365(0.409)

73 -- foliar

Low Growing 

Berry (including 

0.09 - 0.18

(0.10 - 0.20) NS 0.365

(0.409) 10

0 -- foliar
6

Use Site

Single App.

Rate

in lbs. a.i./A

(kg a.i./ha)

# of 

App

Seasonal 

App. Rate

lbs. a.i./A

(kg

a.i./ha)

MRI

(days) PHI (days) Geographic Restrictions Comments

Cranberry)

Small Fruit Vine 

Climbing (except 

Fuzzy Kiwifruit)

0.09 - 0.18

(0.10 - 0.20) NS

0.365

(0.409)

10 0 -- foliar

0.27 – 0.37

(0.31 – 0.41) NS NS 30 --

soil, chemigation into root-zone through low 

pressure drip, trickle, micro-sprinkler or 

equivalent equipment; basal drench in sufficient 

water to move into root zone.

Tree Nut 0.09 - 0.18

(0.10 - 0.20) NS 0.365(0.409) 14 7 -- foliar

Prickly 

Pear/Cactus 

pear

0.09 - 0.18

(0.10 - 0.20) NS 0.365

(0.409) 14 7 -- foliar, ground only

Soybean Seeds 0.037

(0.41) NA 0.365 NA NS --

Maximum single application rate calculated from 

label restriction of 0.068 mg a.i./seed and an 

assumption of 250,000 seeds planted per acre 

which may occur in North Dakota (USEPA, 2011). 

App=application; MRI=minimum retreatment interval; PHI=preharvest interval; NA=not applicable; NS=not specified; a.i.=active ingredient; A=acre

*Applications limitations were on a single and seasonal application basis. It is possible that the chemical could be applied over multiple seasons to one field.
7

4 ENVIRONMENTAL FATE AND TRANSPORT 

Table 4 summarizes the identity information and physical-chemical properties of 

flupyradifurone. While flupyradifurone reportedly does not dissociate at environmentally 

relevant pH, water solubility does decrease from 3200 mg/L at pH 4 and 7 to 3000 mg/L at pH 9. 

Based on its vapor pressure, water solubility, log octanol-water partition coefficient (KOW), and 

solid-water distribution coefficients (Kd), flupyradifurone is classified as non-volatile from water, 

moist soils, and dry surfaces (OPPTS Guideline 835.6100 classification system). Based on 

flupyradifurone’s log KOW value of 0.08, and log octanol-air partition coefficient (KOA) values of 

11, it is not likely to bioconcentrate in terrestrial organisms.2 This is supported by the predicted 

short half-life in the vapor phase (estimated atmospheric half-life of 0.4 days, Table 5). 

Compounds with a log KOW of three and above are generally considered to have the potential to 

bioconcentrate in aquatic organisms. Because flupyradifurone’s log KOW is 0.08, it is not 

expected to significantly bioconcentrate in aquatic organisms. 

Table 4. Summary of physical-chemical properties of flupyradifurone1

Parameter Value and Units Source and/or Comment

PC Code 122304 --

CAS Number 951659-40-8 --

SMILES Code C1=CC(=NC=C1CN(CC(F)F)C2=CC(OC2)=O)Cl --

Chemical Name Flupyradifurone --

Empirical Formula C12H11ClF2N2O2 --

Molecular Weight 288.68 g/mole --

UV/Visible Absorption λmax (nm): 213 and 259 nm MRID 48843628

Water Solubility at 

20o

C (mg/L)

pH Solubility

MRID 48843644 4 3200

7 3200

9 3000

Vapor Pressure

o

C Vapor Pressure

MRID 48843650. Non-volatile under 

field conditions

Pascal Torr

20 9.1×10-7 6.8×10-9

25 1.7×10-6 1.3×10-8

Henry’s Law constant 

at 20oC 8.1×10-13 atm-m3

/mol (pH 4 and 7) Estimated from vapor pressure 

and water solubility at 20oC. 

Log Dissociation 

Constant (pKa) No dissociation between pH 1 -12 MRID 48843634. Not expected to 

ionize in natural waters

 2

A recent scientific advisory panel (SAP) reported, “Gobas et al. (2003) concluded that chemicals with a log KOA > 5 

can biomagnify in terrestrial food chains if log KOW >2 and the rate of chemical transformation is low. However, 

further proof is needed before accepting these limits without reservations” (USEPA, 2009c). This was also 

supported by Armitage and Gobas’s work completed in 2007 (Armitage and Gobas, 2007). 
8

Parameter Value and Units Source and/or Comment

Octanol-water 

partition coefficient 

(Kow) at 25oC

1.2 (log KOW=0.08) pH 4, 7, and 9 MRID 48843639. Not likely to 

bioconcentrate. 

Air-water partition 

coefficient (KAW) 3.3×10-11 (log KAW = -11)

Estimated from vapor pressure and 

water solubility at 20oC and pH 7. 

Nonvolatile from water.

Octanol-air partition 

coefficient (KOA) 3.6×1010 (log KOA = 11) Estimated from KAW and KOW. 

Solubility in organic 

solvents

Methanol >250 g/L

n-Heptane 0.0005 g/L

Toluene 3.7 g/L

Dichloromethane>250 g/L

Acetone >250 g/L

Ethylacetate >250 g/L

Dimethyl sulfoxide >250 g/L 1

All estimated values were estimated according to “Guidance for Reporting on the Environmental Fate and 

Transport of the Stressors of Concern in Problem Formulations for Registration Review, Registration Review Risk 

Assessments, Listed Species Litigation Assessments, New Chemical Risk Assessments, and Other Relevant Risk 

Assessments” (USEPA, 2010a).

4.1 Transformation Rates in Laboratory Studies

Table 5 summarizes abiotic and biotic transformation data. Study results indicate that 

flupyradifurone is persistent to very persistent3 in soil, sediment and water. Measured aerobic 

soil DT50s of 38 to 401 days are uncertain because of high amounts of unextracted residues 

which may or may not constitute residues of concern. Half-lives calculated assuming that the 

unextracted residues do constitute residues of concern range from 79 to 799 days and are 

approximately double those for parent alone. Flupyradifurone is stable to hydrolysis at pH 4, 7, 

and 9, though it does degrade via aqueous photolysis, with a DT50 of 2.5 days. Under aerobic 

aquatic conditions, DT50 values ranged from 237 to 365 days for parent alone, and from 676 to 

893 days for parent plus unextracted residues.4 Estimated DT50 values for soil photolysis (1 

soil), anaerobic soil metabolism (4 soils), and anaerobic aquatic metabolism (2 sediments) were 

all very high (i.e., >391 days) or not quantifiable (i.e., stable), indicating that these degradation 

pathways contribute little to the dissipation of flupyradifurone. 

 3 According to the Toxic Release Inventory Classification System, chemicals with half-lives greater than 60-days are 

classified as persistent and chemicals with half-lives greater than 180 days are classified as very persistent (USEPA, 

2012a). 4 Unextracted residues in aerobic aquatic metabolism studies were greater than 10% applied radioactivity and it is 

uncertain whether the extraction procedures were sufficiently exhaustive.
9

Table 5. Abiotic and Biotic Transformation Kinetics of Flupyradifurone, Flupyradifurone plus M48 plus M47, and 

Flupyradifurone plus Unextracted Residues. Study

System Details

(Kinetic Equation)

Kinetic Equation 

Fitted1 Value1

Representative 

Half-life to 

Derive Model 

Input (days)2

Reference Or (MRID),

Study Classification

And Comments DT50

(days)

DT90

(days)

Hydrolysis

(50oC)

pH 4

No significant 

degradation Stable MRID 48843667, Fully Reliable

pH 7

pH 9

Atmospheric 

Degradation

Hydroxyl Radical 

(SFO) 0.4 NA Not applicable

Estimated using EPIWEB v.4.1 for 12-hour 

day, 1.5x106 OH- molecules/cm3

.

Flupyradifurone is not expected to undergo 

long range transport in the vapor phase.2

Aqueous Photolysis

(25oC)

pH 7

Sterile

40o

N sunlight

(SFO, SFO**)

2.5

13.0**

8.2

43.2**

2.5

13.0**

MRID 48843669, Fully reliable. Corrected for 

40oN latitude. Furanone ring labeled.

pH 8

Natural water

40o

N sunlight

(SFO, SFO**)

2.5

9.6**

8.4

31.9**

2.5

9.3**

MRID 48843670, Fully reliable. Corrected for 

40oN latitude. Furanone ring labeled.

Soil 

Photolysis

CA loam

pH 6.5, 20o

C

(SFO)

449 1495 Not applicable

MRID 48843672, Fully reliable. Soil photolysis 

is of minor importance for the degradation of 

BYI 02960 under outdoor conditions and a 

major phototransformation product is not 

expected. 

Aerobic Soil Metabolism (20oC)

German AX

pH 6.8, 1.2% OC

(DFOP, DFOP*)

62.9

169*

468

767*

178

258*

Results are shown for combined study results 

for the German and U.S. soils. The furanone 

label soils had a higher percentage of 

unextracted residues than the other labels. 

The differences suggest that at least some of 

the unextracted residues are a degradate.

German HF

pH 7.0, 1.8%OC

(IORE, IORE*)

37.5

78.8*

260

1292*

78.4

389*

German HN

pH 5.9, 2.3%OC

(DFOP, DFOP*)

112

303*

562

1100*

194

343*

German DD

pH 7.7, 4.6%OC

(IORE, IORE*)

45.4

96.7*

249

1510*

75

455*

NE silt loam

pH 6.7, 2.3%OC

(DFOP, SFO*)

215

355*

743

1179*

227

355*

CA sandy loam

pH 7.4, 0.57%OC

(IORE, IORE*)

56.6

173*

378

3139*

114

945*

Argissolo

pH 6.0, %OC 2.8

(SFO, SFO*)

202

296*

671

982*

202

296*
10

Study

System Details

(Kinetic Equation)

Kinetic Equation 

Fitted1 Value1

Representative 

Half-life to 

Derive Model 

Input (days)2

Reference Or (MRID),

Study Classification

And Comments DT50

(days)

DT90

(days)

Latossolo

pH 5.2, %OC 1.8

(DFOP, SFO*)

134

291*

364

966*

97.9

291*

Neossolo

pH 4.9, %OC 0.21

(DFOP, SFO*)

170

221*

1293

734*

484

221*

Gleissolo

pH 4.1, %OC 7.8

(SFO, SFO*)

401

799*

1331

2655*

401

799*

Anaerobic Soil Metabolism (20oC)

German HF soil

pH 6.4, %OC 2.7

(SFO, SFO*)

632

3793*

2098

12601*

632

3793*

MRID 48843686. Reliable with restrictions. 

Dissolve oxygen concentrations were near 1 

mg/L at some time points. Unextracted 

residues exceeded 10%AR but were relatively 

constant post flood.

Sanger, CA 

pH 7.2, %OC 0.45

(SFO) 392 1303 392

MRID 48843687. Reliable with restrictions. 

Oxygen concentrations were near 1 mg/L at 

some time points after flooding but redox 

conditions were appropriate days 30-121 

post flood. Unextracted residues were 

greater than 10%AR but were relatively 

constant during the anaerobic phase.

NE soil 

pH 6.7, %OC 1.9 Essentially stable over 30 days

MRID 48843688. Reliable with restrictions. 

Study terminated 60 days after flooding. No 

loss over 30 days of appropriate redox 

conditions.

Aerobic Aquatic (20oC)

German pond HW

pH 7.4, 3.59 %OC 

20o

C

(IORE, SFO*)

237

893*

1818

2965*

547

893* MRID 48843690 and 48843692. Reliable with 

restrictions due to presence of unextracted 

residues at greater than 10% applied 

radioactivity. Results are shown for combined 

study results. 

German gravel pit 

(AW)

pH 7.0, 1.20 %OC

20o

C

(IORE, SFO*)

365

676*

5793

2247*

1740

676*

Anaerobic Aquatic 

(2

4oC)

KS pond 

Water: pH 8.3, 

7.8% OC

(SFO)

1999

Stable*

6640

Stable*

1999

Stable* MRID 48843689. Reliable with restrictions. 

Up to 12%AR present as unextracted residues 

in NC system and it is uncertainty whether

the extraction procedure was sufficiently 

exhaustive.

NC pond 

Water: pH 7.4, 

11.9%OC

(SFO, SFO*)

416

2470*

1381

8204*

416

2470*
11

OC=organic carbon; DTX=time for concentration/mass to decline by X percentage; SFO=single first order; 

DFOP=double first order in parallel; IORE=indeterminate order (IORE); SFO DT50=single first order half-life; TIORE=the 

half-life of a SFO model that passes through a hypothetical DT90 of the IORE fit; DFOP slow DT50=slow rate half-life 

of the DFOP fit, NA=not available, AR=applied radioactivity * Value calculated for parent and unextracted residues which may or may not be parent. These values are relevant 

in understanding the uncertainty in data due to unextracted residues. 

** Value calculated for parent plus M47 plus M48. 

1 DT50 and DT90 values were calculated using nonlinear regression and SFO, DFOP, or IORE equations. The 

equations can be found in the document, Standard Operating Procedure for Using the NAFTA Guidance to 

Calculate Representative Half-life Values and Characterizing Pesticide Degradation (USEPA, 2012c). 2 The value used to estimate a model input value is the calculated SFO DT50, TIORE, or the DFOP slow DT50 from the 

DFOP equation. The model chosen is consistent with that recommended using the, Guidance for Evaluating and 

Calculating Degradation Kinetics in Environmental Media (NAFTA, 2012). The same kinetic equation used to 

determine the representative model input value was used to describe the DT50 and DT90 results based on standard 

kinetic equations.

Four degradates were present in one or more fate studies at greater than 10% of applied 

radioactivity (AR):

• 6-chloronicotinic acid (6CNA),

• difluoroacetic acid (DFA),

• BYI 02960-succinamide (M48), and

• BYI 02960-azabicyclosuccinamide (M47).

Table 6 summarizes available degradation studies for 6CNA and DFA; 6CNA is degraded rapidly 

in three aerobic soil systems (DT50 ranged from 3 to 7 days). The degradate DFA was persistent 

to very persistent in two aerobic aquatic systems (DT50 ranged from 121 to 951 days).

Table 6. Biotic degradation kinetics for 6CNA and DFA 

Study

System Details

(Kinetic Equation) DT50 (days) Reference Or (MRID),Study Classification

Aerobic Soil 

Metabolism –

6CNA

UK sandy loam, 20oC

pH 6.7, 3.1%OC (IORE) 3.5

MRID 44651882. Reliable with 

restrictions.

UK clay, 20oC

pH 7.8, 3.8%OC (IORE) 2.7

UK loam, 20oC

pH 7.2, 2.9%OC (IORE) 6.5

Aerobic 

Aquatic 

Metabolism -

DFA

German pond HW, 20oC

pH 7.4, 3.59 %OC (SFO, SFO*)

121

226* MRID 48843691. Reliable with 

German gravel pit (AW), 20 restrictions. oC

pH 7.0, 1.20 %OC (SFO) 951

OC=organic carbon; DT50=time for concentration/mass to decline by 50%; SFO=single first order; DFOP=double first 

order in parallel; IORE=indeterminate order (IORE) 

* Value calculated for parent and unextracted residues which may or may not be parent. These values are relevant 

in understanding the uncertainty in data due to unextracted residues. 

1 DT50 values were calculated using nonlinear regression and SFO, DFOP, or IORE equations. The equations can be 

found in the document, Standard Operating Procedure for Using the NAFTA Guidance to Calculate Representative 

Half-life Values and Characterizing Pesticide Degradation (USEPA, 2012c).
12

4.2 Sorption and Mobility

Study results indicate that soil sorption of flupyradifurone is influenced by percent organic 

carbon (Table 7). Based on organic-carbon water normalized soil-water distribution coefficients 

(Koc) ranging from 80 to 283 L/kg-organic carbon (measured in 10 soils), flupyradifurone is 

classified as mobile to moderately mobile (FAO, 2000) (MRID 48843662, 48843663, 48843664). 

The degradate, 6CNA, is mobile to moderately mobile, with Koc values ranging from 17.2 to 134 

L/kg in five soils and one sediment (FAO, 2000) (MRID 44651884). DFA is highly mobile, with Koc

values ranging from 1.55 to 8.75 L/kg in five soils (FAO, 2000) (MRID 48843665). Both 6CNA 

and DFA have the potential to leach to groundwater. Sorption data are not available for M47 

and M48.

Table 7. Summary of Submitted Sorption Studies for Flupyradifurone and its Degradates 2-chloronicotinic acid

(6CNA), and difluoroacetic acid (DFA)

Soil texture

Source

% 

OC

soil 

pH

Regressed 

Kd

(L/kg-soil)

KOC

(L/kg-OC) KF

(mg/L)(mg/kg)-1/n 1/n

KFOC

(mg/L) (mg/kg)-

1/n

Parent, 20oC, MRID 48843662, Fully Reliable

Sandy loam

AX, Germany 2.1 6.2 2.193 104.4 2.077 0.8445 98.9

Loam

HF, Germany 2.4 6.6 2.353 98.05 2.213 0.8682 92.2

Loam

HN, Germany 2.2 5.3 2.506 113.9 2.354 0.8643 107.0

Loam

DD, Germany 5.1 7.2 4.118 80.74 3.822 0.8648 74.9

Parent, 20oC, MRID 48843663, Fully Reliable 

Sandy loam

California 0.7 6.8 0.627 89.5 0.597 0.9021 85.2

Silt loam, 

Nebraska 1.9 6.5 2.824 148.6 2.512 0.8505 132.2

Parent, 20oC, MRID 48843664, Fully Reliable

Clay, Argissolo, 

Brazil 2.8 5.66 7.104 254 6.7 0.8153 241

Clay,Latossolo, 

Brazil 1.7 4.59 1.462 86 1.5 0.9263 86

Loamy sand, 

Neossolo, Brazil 0.5 4.93 0.563 113 0.6 0.9246 115

Silty clay loam, 

Gleissolo, Brazil 7.8 3.51 22.07 283 21.1 0.8317 270

2-chloronicotinic acid, MRID 44651884, Fully Reliable

Loamy sand 1

NC 0.25 4.4 0.335 134 0.377 0.803 151

Loamy sand 2

NC 1.5 6.2 0.863 57.6 0.818 1.11 54.5

Silt loam

MS 0.44 6.6 0.244 55.4 0.274 0.808 62.3
13

Soil texture

Source

% 

OC

soil 

pH

Regressed 

Kd

(L/kg-soil)

KOC

(L/kg-OC) KF

(mg/L)(mg/kg)-1/n 1/n

KFOC

(mg/L) (mg/kg)-

1/n

Clay

MS 0.82 7.5 0.205 17.2 0.21 0.96 17.6

Clay loam

CA 1.2 8.3 0.168 20.5 0.191 0.794 23.3

Sandy loam 

sediment

NC

2.5 5.6 1.64 65.7 1.8 0.762 72.1

DFA, MRID 48843665, Fully Reliable

Silt loam

HF Germany 2.4 6.5 0.210 8.75 0.229 0.910 9.53

Loam

HN Germany 2.9 5.8 0.211 7.27 0.230 0.816 7.94

Clay loam

DD Germany 4.5 7.4 0.361 8.03 0.372 0.964 8.26

Sandy loam 

CA 0.5 6.0 0.030 6.05 0.034 0.703 6.83

Silty clay loam

NE 1.7 6.5 0.026 1.55 0.025 0.719 1.46

NR=not reported

4.3 Field Dissipation

Several terrestrial field dissipation studies have been completed for flupyradifurone (Table 8). 

Studies were all completed on bare ground sites in the U.S. (California, Florida, and Idaho), 

Canada (Ontario, Prince Edward Island, and Saskatchewan) and Europe (Germany, Italy, United 

Kingdom, and Spain). The application rate at each North American site was a single application 

of 0.6 kg a.i./ha. This is higher than the highest proposed single application rate of 0.41 kg 

a.i./ha in the US. For each of the European sites, the application rate was 250 g a.i./ha. The 

study completed for the European sites did not have an independent laboratory validation (ILV) 

and consequently the levels detected and study conclusions are not considered fully reliable. 

However, available information suggests that other than this, the analytical chemistry method 

was acceptable.

Dissipation half-lives for the whole soil profile ranged from 8 to 310 days. Time to 90% loss 

(DT90) values ranged from 205 to greater than 1000 days. At all sites most residues were 

observed in the top 15 cm; however, flupyradifurone was observed up to a depth of 40 cm. 

Field sites varied in percent organic carbon (range from 0.8 to 4.4%OM), soil properties, and pH 

(range from 5.5 to 8.2). Carryover of residues at the end of the sampling period ranged from 8 

to 59% AR, indicating that a portion of applied flupyradifurone does have the potential to build 

up in soil with subsequent applications from year to year. Two of the major degradates 

observed in laboratory studies, 6CNA and DFA, were also observed in the field studies. M47 

and M48 were not looked for in the field dissipation studies.
14

Table 8. Summary of Terrestrial Field Dissipation Study Results For Flupyradifurone MRID (Year)

Study Site,

Crop

Application Rate

Formulation

% Carry 

over of 

residues

(Days)

DT50

(days)

DT90

(days)

Average Max Conc in 

Soil (μg/kg-soil)

Max Depth detected 

(cm)

Comments

Parent DFA 6CNA

48843693 

(2012)

Tulare Co. 

California, USA

(bareground)

Flowable

pH 8.2, 0.9 %OM

28

(272) 55.9+ 767+ 200.6

30

12.4

60*

5.6

15

Reliable with 

restrictions. No 

cropped plots.

48843694

(2012)

Jefferson Co. 

Florida, USA

(bareground)

Flowable

pH 6.5, 0.8%OM

19

(275) 9.62+ 577+ 304.515

8.2

15

5.2

15

48843695

(2012)

Blaine Co. Idaho, 

USA

(bareground)

Flowable

pH 8.0, 1.4%OM

30 (280) 45.6+ 566+ 416.5

30

5.0

106* 10.8

15

48843696

(2012)

Ontario

CANADA

(bareground)

Flowable

pH 7.0, 4.4%OM

25 (337) 99.6+ 751+ 275.2

30

10.9

30*

3.8

15

Prince-EdwardIsland

CANADA

(bareground)

Flowable

pH NA, 3.6%OM

33 (345) 87.8+ 897+ 220.2

30

8.0

30*

4.8

15

Saskatchewan

CANADA

(bareground)

Flowable

pH 7.6, 2.5%OM

59 (337) 304# >1000# 238.5

30

4.7

15

2.1

15

48843697 (2011)

Monheim, 

Germany

(bareground)

Flowable

pH 6.3, 1.2%OM

27 (354) 38.4+ 743+ 236.6

30

11.2

30 NA Reliable with 

restrictions. Missing 

ILV but available 

information suggests 

methods were 

acceptable. No 

cropped plots. 

Application rate (250 

g a.i./ha) much lower 

than maximum 

proposed rate.

Great Chishill, 

United Kingdom

(bareground)

Flowable

pH 5.8, 2.2%OC

45 (394) 310+ > 1000+ 235.9

30

7.2

20 NA

Burscheid, 

Germany

(bareground)

Flowable

pH 6.3, 0.9%OC

22 (357) 42.0+ 476+ 244.9

30

10.1

30 NA
15

MRID 

(Year)

Study Site,

Crop

Application Rate

% Carry 

over of 

residues

(Days)

DT50

(days)

DT90

(days)

Average Max Conc in 

Soil (μg/kg-soil)

Max Depth detected 

(cm)

Comments

Albaro, Italy

(bareground)

Flowable

pH 7.4, 1.3%OC

8 (360) 8.3+ 278+ 267.5

30

8.7

30 NA

Vilobi d’Onyar, 

Spain

(bareground)

Flowable

pH 5.9, 0.7%OC

9 (357) 27.7# 205# 239.6

40

6.1

20 NA

Hanscheider Hof, 

Germany

(bareground)

Flowable

pH 5.5, 1.5%OC

19 (357) 40.8# 477# 252.9

20

13.5

30 NA

NA=not analyzed, ILV=independent laboratory validation, OC=organic carbon, OM=organic matter; 

Conc=concentration

*Detected below the LOQ at the depth.

+ The DFOP equation was used to calculate dissipation kinetics.

# The IORE equation was used to calculate dissipation kinetics.

A study was also conducted examining dissipation of flupyradifurone in water and sediment in 

four outdoor microcosms spiked at two different concentrations (10 and 100 μg/L). Dissipation 

half-lives are summarized in Table 9. DT50 values in the water and whole sediment ranged from 

64 to 109 days and DT90 values ranged from 212 to 363 days. Concentrations of 

transformation products were not followed in the study. 

Table 9. Summary of DT50 and DT90 of flupyradifurone in outdoor microcosm studies (MRID 48843673)

Nominal Test 

Concentration 

(μg/L)

Water Phase Whole System

DT50 (days) DT90 (days) DT50 (days) DT90 (days)

10 63.9 212 74.0 246

100 95.0 316 109 363

5 POSSIBLE TRANSFORMATION PRODUCTS OF TOXICOLOGICAL AND EXPOSURE CONCERN

The following four transformation products were measured in environmental fate studies at 

10% or greater of applied radioactivity: 

• 6-chloronicotinic acid (6CNA);

• difluoroacetic acid (DFA);

• BYI 02960-succinamide (M48); and, 

• BYI 02960-azabicyclosuccinamide (M47).

The following three transformation products were also measured in environmental fate studies, 

at less than 10% of applied radioactivity:
16

• BYI 02960-deschlorohydroxysuccinamide (DCHS);

• BYI 02960-des-difluoroethyl (M19); and,

• BYI 02960-chloro (M01).

IUPAC names, molecular weights, formula’s, and SMILES codes are available for these 

compounds in the document titled, Data on Flupyradifurone and Its Environmental 

Transformation Products in Support of the ROCKs (USEPA, 2013, D415161) . 

Figure 1 shows potential degradation pathways of flupyradifurone based on chemical 

structures and observed transformation products in various studies. 

Figure 1. Potential Degradation Pathway of Flupyradifurone 

Bolded values were present at greater than 10% of applied radioactivity and the asterisk indicates the compound 

was observed in a field study. Abbreviations are defined in text above figure. 

Table 10 shows the maximum percent applied radioactivity for each identified transformation 

product and corresponding study type. The transformation products DFA and 6CNA were

observed in aerobic environments, especially soils, while M48 and M47 were present in 

aqueous photolysis studies. All other transformation products were present at less than 10% 

applied radioactivity. There is some uncertainty as to whether additional major transformation 
17

products would have been identified had the unextracted residues been characterized (which is 

why the unextracted residues have been included in the modeling runs labeled TTR-UN). Many 

of the maximum amount of AR associated with a degradate were observed at the final sampling 

interval. The transformation products looked for in field studies were DFA and 6CNA and they 

were observed at less than 15 μg/L. 

Table 10. Summary of maximum amount of transformation products observed in fate studies

Compound

Maximum % of Applied Radioactivity Associated with Degradate (Time of Peak)

Amount Detected at Final Sampling Interval in Corresponding Study

Hydrolysis

Soil 

Photolysis

Aerobic Soil

Anaerobic 

Soil

Aqueous 

Photolysis

Aerobic 

Aquatic

Anaerobic 

Aquatic

Observed in 

Field 

Dissipation

DFA NA NA 35 (48d)

24 (117d)

27 (37d)

27 (153d) NA NA NA Yes

6CNA NA NA 22 (64d)

6.2 (120d)

15 (14d)

13 (121d) NA NA NA Yes

M48

(succinamide) NA NA NA NA 39 (35hr)a NA NA NA

M47 

(azabicyclosucci

namide)

NA NA NA NA 15 (28hr)a

NA NA

NA

BYI 02960-desdifluoroethyl NA NA 0.5 (59d)

ND (120d) NA NA NA NA NA

BYI 02960-

chloro NA NA 1.8 (120d)a 2.8 (59d)2.4 (121d) NA NA NA NA

DCHS NA NA NA NA 2.8 (35hr)a NA NA NA

Unextracted 

Residues NA 1.1(4d)0.7 (8d) 34 (120d)a 31 (120d)30 (123d) NA 27 (120d)a 12 (102d)a NA

CO2 NA 2.3(8d) 59 (120d)a 27 ND 9 (119d)a 0.1(102d)a NA

NA=not analyzed; ND=not detected a Peak at final sampling interval in some studies.

b In some aerobic soil metabolism studies, significant mineralization occurred while in others minimal 

mineralization occurred (max CO2 in one soil was 4% of AR).

6 RESIDUES OF CONCERN

The Residues of Concern Knowledgebase Subcommittee (ROCKS) reported that the residues of 

concern for flupyradifurone in drinking water are flupyradifurone, DFA, M47, and M48 (USEPA, 

2013, D413192). While all of these residues are considered residues of concern, the way these 

residues are handled in the risk assessment was determined based on the expected toxicity 

pattern and data available for estimating exposure. The aqueous photolysis degradates M47

and M48, are only expected to influence the surface water Estimated Drinking Water 

Concentrations (EDWCs) as the aqueous photolysis data are not used in groundwater modeling,

and these degradates were only observed in the aqueous photolysis study. There were 

unextracted residues quantified in the soil and aquatic metabolism studies at levels high 
18

enough to influence EDWCs, when the unextracted residues were considered in calculating 

modeling inputs. The chemical composition of the unextracted residues is unknown (e.g., they 

could be parent or one of the other identified residues of concern or a residue that is not of 

concern). Therefore, to be protective, EDWCs were calculated assuming that the unextracted 

residues are residues of concern. A total toxic residue (TTR) approach was used to calculate

EDWCs for residues of flupyradifurone, M47, M48, and unextracted residues. In this approach, 

in the laboratory fate studies, the amount of radioactivity associated with flupyradifurone, 

M47, M48, and unextracted residues was summed, and degradation kinetics were calculated

for the combined residues. The degradation kinetic results calculated in this way are used in 

modeling to estimate EDWCs for total residues. The same approach was also employed 

excluding the unextracted residues, in order to bracket the uncertainty caused by the presence 

of high amounts of unextracted residues in fate studies. EDWCs for DFA were calculated 

separately because DFA has a different mode of action and substantially different structure 

then flupyradifurone, M47, and M48.

7 MODELING APPROACH AND INPUT PARAMETERS

EDWCs were calculated for the following residues of concern:

• total residues of parent plus M47 plus M48 plus unextracted residues (TTR-UN),

• total residues of parent plus M47 plus M48 (TTR), and

• residues of DFA.

The EDWCs for residues of DFA were determined in part by estimating an “application rate” for 

DFA by multiplying the application rate for the parent by the ratio of the molecular weight of

DFA divided by the molecular weight of parent. This is a conservative methodology of 

estimating possible DFA residues in drinking water because not all of the parent is expected to 

degrade to DFA. This estimate can be refined if needed by considering the amount of DFA 

formed in fate studies. 

7.1 Models

7.1.1 SCI-GROW (Groundwater)

Screening Concentration in Ground Water (SCI-GROW v2.3, Jul. 29, 2003) is a regression model 

used as a screening tool to estimate pesticide concentrations found in groundwater used as 

drinking water. The SCI-GROW model and user’s manual may also be downloaded from the 

EPA Water Models web-page (http://www.epa.gov/oppefed1/models/water/#scigrow). 

7.1.2 PRZM-GW (Groundwater)

Tier 1 groundwater EDWCs for flupyradifurone were derived with PRZM-GW (Pesticide Root 

Zone Model for Groundwater, version 1.0, August 31, 2012), using the GW-GUI (Graphical User 

Interface, version 1.0, August 31, 2012) (Baris et al., 2013). PRZM-GW is a one-dimensional 

leaching model used to estimate potential concentrations of pesticides in groundwater. The 
19

model accounts for pesticide fate in the crop root zone by simulating transport and degradation 

occurring throughout the soil profile after a pesticide is applied to an agricultural field. PRZMGW permits the simulation of multiple years of pesticide application (up to 100 years) on a 

single site. Six standard scenarios, each representing a different region known to be vulnerable 

to groundwater contamination, are currently available for use with PRZM-GW for risk 

assessment purposes. In the PRZM-GW simulations for this assessment, all of these standard 

scenarios were used. PRZM-GW outputs represent pesticide concentrations in a vulnerable 

groundwater supply located directly beneath an agricultural field. Percent Cropped Area 

adjustment factors (PCAs) are not applied to the results of groundwater modeling, such as 

those generated by either the SCI-GROW or PRZM-GW models. 

7.1.3 PRZM/EXAMS (Surface Water, Non-Cranberry Uses)

Estimated drinking water concentrations (EDWCs) in surface water were generated using 

EFED’s Tier II aquatic models: PRZM (Pesticide Root Zone Model; version. 3.12.3, June 2006) 

(Carsel et al., 1997) and EXAMS (EXposure Analysis Modeling System; Version. 2.98.04.06, April 

2005) (Burns, 2000). Calculations were carried out with the linkage program shell – PE version 

5.0 (November 2006) – which implements the standard crop scenarios developed by EFED

(USEPA, 2006). 

PRZM simulates pesticide fate and transport as a result of leaching, direct spray drift, runoff 

and erosion from an agricultural field, and EXAMS estimates resulting concentrations of 

pesticides in an adjacent surface water body over a 30-year period. The combined models are 

expected to provide high-end estimates of pesticide concentrations that might be found in 

vulnerable aquatic environments following pesticide application. The location of the field is 

specific to the crop being simulated using site-specific information on the soils, weather, 

cropping, and management factors associated with the scenario. The crop/location scenario is 

intended to represent a high-end exposure site on which the crop is normally grown. Based on 

historical rainfall data, the receiving water body receives multiple runoff (and possibly spray 

drift) event loadings over the course of the simulated time span. Weather and agricultural 

practices are simulated for 30 year periods (1961 through 1990) so that the 1-in-10-year 

exceedance probability concentration at the site can be estimated. Additional information on 

PRZM and EXAMS can be found at: http://www.epa.gov/oppefed1/models/water/. For

drinking water exposure assessments, the Index Reservoir (IR) receiving water body is used in 

lieu of the standard pond. The IR is used in a manner similar to that in which the standard pond 

is used in ecological exposure assessments, except that the IR is simulated as a flow-through 

system, with a scenario-specific steady flow rate based upon the daily-mean runoff over the 

duration of a simulation (a function of local weather conditions). The IR is approximately 82-m 

wide and 640-m long, with an area of 5.3 hectare (USEPA, 1998, 2010b). The area of the entire 

watershed draining to the IRis 172.8 ha. Guidance for using the IR is located at: 

http://www.epa.gov/oppefed1/models/water/index_reservoir_dwa.html. 
20

7.1.4 Cranberry Modeling for Surface Water

To determine EDWCs for cranberry use, EFED used the EFED Tier 1 Rice Model (v1.0, May 8, 

2007). The Tier 1 Rice Model is used to estimate aquatic exposures for direct application to 

water. The Tier 1 Rice Model estimates one concentration that represents both acute and 

chronic exposures. The Tier 1 Rice model estimates concentrations in a water body holding a 

10 cm water depth. When a pesticide is applied to the water, the model employs the 

assumption that the pesticide instantaneously partitions between water and sediment, as 

determined by the chemical’s sorption coefficient, according to:

( ) w sed sed b d

ai

w d d K

m C

θ ρ3

2

0 10

10 '

− + + =

and, if appropriate:

Kd KOC = 0.01

where,

Cw0 = initial water concentration [μg/L]

mai' = mass applied per unit area [kg/ha]

Kd = water-sediment partitioning coefficient [L/kg]

KOC = organic carbon partitioning coefficient [L/kg]

dw = water column depth = 0.10 m

dsed = sediment depth = 0.01 m

θsed = porosity of sediment = 0.509

ρb = bulk density of sediment = 1300 kg/m3

This simplifies to:

And, if appropriate:

Kd = 0.01Koc

Where: 

Cw=water concentration in μg/L

mai’=mass applied per unit area in kg/ha

Kd=soil-water distribution coefficient (L/kg-soil)

Koc=organic-carbon normalized soil-water distribution coefficient (L/kg-oc)
21

This model was used for this assessment with a modification to the depth of the water body, to 

reflect concentrations in the water of a cranberry bog rather than that of a rice paddy (Cape 

Cod Cranberry Growers Association, 2001). Specifically, in the first equation above, the value of 

dw (water column depth) was changed to 0.305 m (1 foot), from the usual 0.10 m depth that is 

assumed for rice paddies. This modification has been used in a previous assessment, to 

estimate aquatic exposure concentrations for the chemical fenpyroximate (USEPA, 2012, 

D391431, 2012, D405064). 

7.1.5 Percent Cropped Area Adjustment Factor

Percent Cropped Areas (PCA) that account for the maximum area within a watershed that may 

be planted with a modeled crop are applied to concentrations predicted by FIRST or PRZM and 

EXAMs according to Guidance on Development and Use of Percent Cropped Area Adjustment 

Factors in Drinking Water Exposure Assessments (USEPA, 2012b). Flupyradifurone has 

proposed uses on a variety of agricultural crops. Therefore, the EDWCs from PRZM/EXAMS 

were multiplied by the national default PCA of 0.91 representing all-agriculture.

7.2 Input Parameters

Summaries of the model input parameter values used in SCI-GROW, PRZM-GW, PRZM/EXAMS, 

and the Tier I Rice Model are presented in Table 12, 13, 14, and 15, respectively. Input 

parameters were selected in accordance with EFED’s “Guidance for Selecting Input Parameters 

in Modeling the Environmental Fate and Transport of Pesticides,” Version 2.1 (USEPA, 2009a)

and “Guidance for Selecting Input Parameters for Modeling Pesticide Concentrations in 

Groundwater Using the Pesticide Root Zone Model,” Version 1 (USEPA and Canada, 2013). 

Sorption Coefficients

TTR-UN: Coefficients of variations (CV) were lower for organic carbon normalized solid-water 

distribution coefficients (KOC; CV=53%) as compared to solid-water distribution coefficients (Kd; 

CV=140%). Therefore, the mean KOC (137 L/kg-OC) was used to estimate flupyradifurone

concentrations with PRZM-GW and PRZM/EXAMS, and the median KOC (109 L/kg) was used to 

estimated groundwater concentrations with SCI-GROW. 

DFA: Coefficients of variations (CV) were lower for organic carbon normalized solid-water 

distribution coefficients (KOC; CV=45%) as compared to solid-water distribution coefficients (Kd; 

CV=84%). Therefore, the mean KOC (6.3 L/kg-OC) was used to estimate flupyradifurone 

concentrations with PRZM-GW and PRZM/EXAMS, and the median KOC (7.3 L/kg) was used to 

estimated groundwater concentrations with SCI-GROW. 

Aerobic Soil Metabolism

TTR: The aerobic soil metabolism input value used in PRZM-GW and PRZM/EXAMS was 

calculated as the 90 percent upper confidence limit on the mean of ten representative half-life 
22

values. The aerobic soil metabolism input value used in SCI-GROW was the median of the same 

representative half-life values. Consistent with the input parameter guidance, the 

representative half-lives for PRZM-GW were adjusted to a temperature of 25o

C (USEPA and 

Health Canada, 2012). Temperature adjustments were not completed for other models.

DFA: Aerobic soil metabolism studies where DFA was the starting material were not available. 

DFA was observed in three aerobic soil metabolism studies where the ethyl group was 

radiolabeled (MRID 48843679). A regression was completed using the results from sampling 

points where the maximum amount of DFA was observed, and subsequent data points. Results

from the three studies were used to estimate the 90th percentile upper confidence limit on the 

mean half-life. These calculated values for DFA are presumed to be conservative and may 

underestimate decay because DFA may have been forming at the same time as it was declining. 

Consistent with the input parameter guidance, the representative half-lives for PRZM-GW were 

adjusted to a temperature of 25o

C (USEPA and Health Canada, 2012). Temperature 

adjustments were not employed for the aerobic soil inputs to other models.

Aerobic Aquatic Metabolism

TTR: The aerobic aquatic metabolism input value used in PRZM-GW and PRZM/EXAMS was 

calculated as the 90 percent upper confidence limit on the mean of two representative half-life 

values. Half-life values were adjusted from 20o

C to 25oC according to input parameter 

guidance.

DFA: The aerobic aquatic metabolism input value used in PRZM-GW and PRZM/EXAMS was 

calculated as the 90 percent upper confidence limit on the mean of two representative half-life 

values. Half-life values were adjusted from 20oC to 25oC according to Guidance for Making 

Temperature Adjustments to Metabolism Inputs to EXAMs and PE5 (USEPA, 2010c).

Scenarios and Application Dates Chosen for PRZM/EXAMS modeling

Scenarios are used to specify soil, climatic, and agronomic inputs in PRZM, and are intended to 

result in high-end water concentrations associated with a particular crop and pesticide within a 

geographic region. Each PRZM scenario is specific to a location. Soil and agronomic data 

specific to the location are built into the scenario, and a specific climatic weather station 

providing 30 years of daily weather values is associated with the location. Table 11 identifies

the use sites associated with each PRZM scenario. For foliar and soil applications to agricultural 

crops, the date of application was chosen as the day when the crop was present on the field 

and during a period of generally high rainfall as it is expected that flupyradifurone may be used 

when the crop is on the field and during periods of high rainfall. Crop-specific management 

practices were used for modeling, including maximum application rates, maximum numbers of 

applications per year, minimum re-application intervals, and the first application date for each 

crop. For the seed treatment use, the application date was chosen as two weeks before crop 

emergence.
23

Table 11. Use site group, associated crops, and PRZM scenarios used to calculate EDWC for the use site group

Use Site Crops Associated with Use Site Scenarios

Crop Group 15: 

Cereal Grains 

(except Rice)

Barley; buckwheat; corn; millet, pearl; millet, proso; oats; 

popcorn; rye; sorghum (milo); teosinte; triticale; wheat

IAcornSTD

ILcornSTD

KSsorghumSTD

MNCornSTD

MScornSTD

NCcornESTD

NDwheatSTD

OHcornSTD

ORwheatOP

PAcornSTD

INcornSTD

MNcornSTD

NEcornSTD

Cotton Cotton

CAcottonWirrigSTD

MScottonSTD

NCcottonSTD

TXcottonOP

Nongrass Animal 

Feeds (Forage, 

Fodder, Straw, Hay)

Alfalfa; bean, velvet; clover (Trifolium , Melilotus); kudzu; 

lespedeza; lupin; sainfoin; trefoil; vetch; vetch, crown; vetch, 

milk

CArangelandhayRLF_V2

NCalfalfaOP

PAalfalfaOP

TXalfalfaOP

ILalfalfaNMC

Peanut peanut NCpeanutSTD

Root Vegetables 

(except Sugarbeet)

Arracacha; arrowroot; artichoke, Chinese; artichoke, Jerusalem; 

beet, garden; beet, sugar; burdock, edible; canna, edible; carrot; 

cassava, bitter and sweet; celeriac; chayote (root); chervil, 

turnip-rooted; chicory; chufa; dasheen (taro); ginger; ginseng; 

horseradish; leren; parsley, turnip-rooted; parsnip; potato; 

radish; radish, oriental; rutabaga; salsify; salsify, black; salsify, 

Spanish; skirret; sweet potato; tanier; turmeric; turnip; yam 

bean; yam, true.

FlcarrotSTD

FLpotatoNMC

IdpotatowirrigSTD

MEpotatoSTD

MIasparagusSTDv2

MNsugarbeetSTD

Ormint

CAgarlicRLFV3

NCSweetPotatoSTD

CARowCropRLF_V2.txt

Tuberous and Corm 

Vegetables

Arracacha; arrowroot; artichoke, Chinese; artichoke, Jerusalem; 

canna, edible; cassava, bitter and sweet; chayote (root); chufa; 

dasheen (taro); ginger; leren; potato; sweet potato; tanier; 

turmeric; yam bean; yam, true

CAPotatoRLF

IDNpotato_WirrigSTD

MEpotatoSTD

FLpotatoNMC

NCsweetpotatoSTD

CAgarlicRLFV3

Leafy Vegetables 

(except Brassica)

Amaranth (Chinese spinach); arugula (roquette); cardoon; 

celery; celery, Chinese; celtuce; chervil; chrysanthemum, edibleleaved; chrysanthemum, garland; corn salad; cress, garden; 

cress, upland; dandelion; dock (sorrel); endive (escarole); fennel, 

Florence; lettuce, head and leaf; orach; parsley; purslane, 

garden; purslane, winter; radicchio (red chicory); rhubarb; 

spinach; spinach, New Zealand; spinach, vine; Swiss chard

CAColeCropRLF

FLcucumberSTD

CAlettuceSTD

FLcabbageSTD

Brassica (Cole) Leafy 

Vegetables

Broccoli; broccoli, Chinese (gai lon); broccoli raab (rapini); 

Brussels sprouts; cabbage;Chinese (bok choy); cabbage, Chinese 

(napa); cabbage, Chinese mustard(gai choy); cauliflower; cavalo 

broccolo; collards; kale; kohlrabi; mizuna; mustard greens; 

CAColeCropRLF

FLcucumberSTD

FLtomatoSTD

CAlettuceSTD
24

Use Site Crops Associated with Use Site Scenarios

mustard spinach; rape greens FLcabbageSTD

Legume Vegetables 

(Succulent or Dried)

Bean (Lupinus) (includes grain lupin, sweet lupin, white lupin, 

and white sweet lupin); bean (Phaseolus) (includes field bean, 

kidney bean, lima bean, navy bean, pinto bean, runner bean, 

snap bean, tepary bean, wax bean); bean (Vigna) (includes 

adzuki bean, asparagus bean, blackeyed pea, catjang, Chinese 

longbean, cowpea, crowder pea, moth bean, mung bean, rice 

bean, southern pea, urd bean, yardlong bean); broad bean 

(fava); chickpea (garbanzo); guar; jackbean; lablab bean; lentil; 

pea (Pisum) (includes dwarf pea, edible-podded pea, English 

pea, field pea, garden pea, green pea, snowpea, sugar snap pea); 

pigeon pea; soybean; soybean (immature seed); sword bean

MIbeansSTD

ORsnbeansSTD

CARowCropRLF_V2

Fruiting Vegetables 

(except cucurbits)

Eggplant; groundcherry (Physalis spp); pepino; pepper (includes 

bell pepper, chili pepper, cooking pepper, pimento, sweet 

pepper); tomatillo; tomato

CatomatowirrigSTD

FLtomatoSTD_V2

PAtomatoSTD

FLpeppersSTD

Cucurbit Vegetables

Chayote (fruit); Chinese waxgourd (Chinese preserving melon); 

citron melon; cucumber; gherkin; gourd, edible (includes hyotan, 

cucuzza, hechima, Chinese okra); Momordica spp (includes 

balsam apple, balsam pear, bittermelon, Chinese cucumber); 

muskmelon (includes cantaloupe); pumpkin; squash, summer; 

squash, winter (includes butternut squash, calabaza, hubbard 

squash, acorn squash, spaghetti squash); watermelon

CAMelonsRLF

FLcucumberSTD

NJmelonSTD

MImelonSTD

MOmelonSTD

Hop Hop ORhopsSTD

Citrus Fruit

Calamondin; citrus citron; citrus hybrids (includes chironja, 

tangelo, tangor); grapefruit; kumquat; lemon; lime; mandarin 

(tangerine); orange, sour; orange, sweet; pummelo; Satsuma 

mandarin

Cacitrus_WirrigSTD

FLcitrusSTD

Pome Fruit

Apple; azarole; crabapple; loquat; mayhaw; medlar; pear; pear, 

Asian; quince; quince, Chinese; quince, Japanese; tejocote; 

cultivars, varieties, and/or hybrids of these

NCappleSTD

ORappleSTD

PAappleSTD

CAfruit_WirrigSTD

Bushberry Blueberry, highbush and lowbush; currant; elderberry; 

gooseberry; huckleberry ORberriesOP

Low Growing Berry 

(including 

Cranberry)

Bearberry; bilberry; blueberry, lowbush; cloudberry; cranberry; 

lingonberry; muntries; partridgeberry; strawberry; cultivars, 

varieties, and/or hybrids of these

Flstrawberry_WirrigSTD

OrberriesSTD 

CAStrawberrynoplasticRLF

FLstrawberry_WirrigSTD

ORberriesOP

Small Fruit Vine 

Climbing (except 

Fuzzy Kiwifruit)

Amur river grape; gooseberry; grape; kiwifruit, fuzzy; kiwifruit, 

hardy; maypop; schisandra berry; cultivars, varieties, and/or 

hybrids of these

ORberriesOP

NYGrapesSTD

CAWineGrapesRLF

OrberriesSTD (07-04)

CAfruit_WirrigSTD.txt

Tree Nut African nut-tree; almond; beechnut; Brazil nut; Brazilian pine; CAalmond_WirrigSTD
25

Use Site Crops Associated with Use Site Scenarios

bunya; bur oak; butternut; Cajou nut; candlenut; cashew; 

chestnut; chinquapin; coconut; coquito nut; dika nut; ginkgo; 

Guiana chestnut; hazelnut (filbert); heartnut; hickory nut; 

Japanese horse-chestnut; macadamia nut; mongongo nut; 

monkey-pot; monkey puzzle nut; Okari nut; Pachira nut; peach 

palm nut; pecan; pequi; Pili nut; pine nut; pistachio; Sapucaia 

nut; tropical almond; walnut, black; walnut, English; yellowhorn; 

cultivars, varieties, and/or hybrids of these

ORfilbertSTD

GApecanSTD

Prickly Pear/Cactus 

pear

CAcitrusSTD

Soybean Seeds MSsoybeanSTD

Currently approved standard PRZM crop scenarios were used in modeling when available. The 

low-growing berry subgroup includes cranberry, bearberry, bilberry, cloudberry, muntries,

partridgeberry, and strawberry. Low growing berries include both berries grown on the ground 

(strawberries) and berries grown on shrubs. The ORberriesOP and the Flstrawberry_WirrigSTD 

scenarios were used for the low growing berry subgroup. Additionally, a modified version of 

the Tier I Rice model was used to calculate an EDWC for the use on cranberries. The 

ORberriesOP scenario (this scenario was developed for the organophosphate cumulative 

assessment) was prepared for use on blackberries and is representative for berries grown on 

shrubs. Flupyradifurone is not an organophosphate class chemical; however, the 

organophosphate berry scenario is the only scenario available for this type of crop. The Root 

Vegetables Crop Group includes the following: garden beet, burdock, carrot, celeriac, turniproot chervil, chicory, ginseng, horseradish, turnip rooted parsley, parsnip, radish, Oriental 

radish, rutabega, salsify, black salsify, Spanish salsify, skirret, and turnip. The following 

scenarios were chosen for this crop group: FlcarrotSTD, IDpotatowirrigSTD, MEpotatoSTD, 

MIasparagusSTDv2, and ORmint. The asparagus and sugarbeet scenarios were chosen to be 

representative of use on ginseng. OrmintSTD was chosen to be representative of use on 

parsley. To represent use on turnip greens, the FlcarrotSTD scenario and the MEpotatoSTD 

were chosen. 

Unlike our standard crop scenarios, the organophosphate (OP)-cumulative scenarios were not 

developed specifically to target a high-end exposure site for the particular crop. Instead, these 

scenarios were developed by first identifying areas of high combined use of the entire OP class 

of chemicals that coincided with drinking water intakes that draw from surface water sources. 

Within these high OP-use areas, major crop uses were identified and scenarios were developed 

to represent high runoff-prone soils known to support the crops in these areas. In some 

instances, these scenarios may represent the major growing area for a particular crop. In other 

instances, the major crop area may be elsewhere, and the scenario in the high OP-use area may 

represent a "fringe" area of the crop in question. It has not been determined how the 

vulnerability of a crop scenario developed for the OP cumulative assessment compares to a 

standard scenario developed for the same crop. The OP scenarios may represent either greater 

or lesser vulnerability than standard scenarios. Because the OP scenarios focused on areas that 

coincided with drinking water intakes, their suitability as high-end vulnerable scenarios for 
26

ecological exposure assessments is less certain. The California red legged frog (Rana draytonii) 

scenarios were developed in support of risk assessments conducted to evaluate potential risks 

to this listed species in California. These scenarios have similar issues as the scenarios 

developed for the OP assessments, except that they were not chosen based on proximity to 

drinking water intakes, but rather to evaluate specific uses of pesticides in California. They may 

not be representative of vulnerable areas across the United States.

Table 12. SCI-GROW (v2.3) Input Parameter Values for Total Residues of Flupyradifurone plus M47 plus M48 

(abbreviated as “TTR”) plus unextracted residues (abbreviated as “TTR-UN”) and for difluoroacetic acid alone 

(DFA)1

Parameter Residues Value Source Comments

Application Rate (lbs 

residue/acre)

TTR

TTR-UN See 

Table 

16 to 

18

Proposed label

Maximum application rate for active ingredient

DFA

Maximum application rate for parent × MW of 

DFA (96.03 g/mole) / MW of parent (288.68 

g/mole)

# of Applications All --

Koc (mL/g)

TTR

TTR-UN 109

MRIDs 

48843662, 

48843663, and 

48843664

Median of 10 KOC values. There is not a threefold difference in observed values.

DFA 7.3 MRID 

48843665

Median of five KOC values. There is not a threefold difference in observed values.

Aerobic Soil 

Metabolism Half-life

(days)

TTR-UN 349 MRIDs 

48843674, 

48843676, 

48843677, 

48843679, 

48843681, 

48843683

Median of 10 values. There is a five-fold 

difference between the lowest (75 days) and 

highest representative half-lives (484 days) for 

TTR. There is not a 5-fold difference for TTR-UN.

No temperature conversion was completed.

TTR 186

DFA 134 MRID 

48843679

DFA degradation kinetics calculated using the 

maximum amount observed in the study and 

subsequent sampling points for DFA. The 

calculation methodology does not account for 

the fact that DFA was forming and degrading at 

the same time.

TTR-UN: Value for total residues of flupyradifurone, M47, M48, and unextracted residues. 

TTR: Value for total residues of flupyradifurone, M47, and M48. 

DFA: Value for modeling difluoroacetic acid.

Table 13. Tier I PRZM-GW Input Parameters

Parameter (units) Residues Input Value Data Source Comments

Application Rate 

(kg residue/ha)

TTR-UN

TTR

See Table 17 and 18

Proposed 

label

Maximum application rate for 

flupyradifurone.

DFA

Maximum application rate for parent 

× MW of DFA (96.03 g/mole) / MW of 

parent (288.68 g/mole)

Number of 

Applications All --
27

Application Date(s) All See Table 17 and 18 --

Applications Occur 

Every

All

1/year and from 

year 1 to the last 

year

--

Application 

Method All

Above canopy (2)

Soil (1) seed 

treatment

--

Date of First 

Application All residues

10 days after crop 

emergence for 

foliar

14 days before crop 

emergence for seed 

treatment

-- Assumed

Hydrolysis Half-life

(days) All Stable (0) MRID 48843667 --

Soil Metabolism 

Half-life at 25o

C 

(days)

TTR-UN 371 MRIDs 

48843674, 

48843676, 

48843677, 

48843679, 

48843681, 

48843683

The 90 percent upper confidence 

bound on the mean of ten half-life 

values. Half-life values adjusted from 

20

o

C to 25oC according to input 

parameter guidance.

TTR 124

DFA 110 MRID 

48843679

The 90 percent upper confidence 

bound on the mean of three half-life 

values. Half-life values adjusted from 

20o

C to 25oC according to input 

parameter guidance.

Koc (L/kg-OC)

TTR-UN

TTR 137

MRIDs 

48843662, 

48843663, 

48843664

Mean of ten KOC values for 

flupyradifurone.

DFA 6.33 MRID 

48843665 Mean of five KOC values for DFA.

Table 14. Input Values Used for Tier II Surface Water Modeling with PRZM/EXAMS

Parameter (units) Residue Value (s) Source Comments

PRZM Scenario All See Table 16 

and 18 -- Screening scenario that is expected to result in a high end EDWC.

EXAMS environment All ir298.exv -- Index Reservoir

Field Size All Index 

Reservoir -- --

Molecular Weight (g/mol)

TTR-UN

TTR 288.68 -- --

DFA 96.03 -- --

Henry’s Law Constant 

(atm-m3

/mol)

TTR-UN

TTR 8.1×10-13 -- Estimated from vapor pressure at 

25o

C and water solubility at 20oC.

DFA 8.8×10-14 --
28

Parameter (units) Residue Value (s) Source Comments

Vapor Pressure (Torr) at 

25o

C

TTR-UN

TTR 1.3×10-8 MRID 

48843650 --

DFA 3.5×10-7 MRID 

48843652 4.7 ×10-5 Pascal at 25o

C

Solubility in Water @ 20 

O

C, pH not reported (mg/L)

TTR-UN

TTR 3200 MRID 48843644

20oC and pH 7

DFA 500000 MRID 

48843648

The water solubility of DFA at 20oC 

was above 500 g/L in a pH range of 

1.6 to 13.0

Organic-carbon 

Normalized Soil-water 

Distribution Coefficient 

(KOC (L/kg-OC))

TTR-UN

TTR 137

MRIDs 

48843662, 

48843663, 

48843664

Mean of ten KOC values for 

flupyradifurone.

DFA 6.33 MRID 

48843665 Mean of five KOC values for DFA.

Chemical Application 

Method (CAM) All

2 (foliar)

1 (seed 

treatment and 

soil)

Proposed 

Label --

Depth of Incorporation All 0 -- Not specified on the label.

Application Rate (kg/ha)

TTR-UN

TTR

See Table 16 

and 18

Proposed 

label

Maximum application rate for 

active ingredient

DFA

Maximum application rate for 

parent × MW of DFA (96.03 

g/mole) × MW of parent (288.68 

g/mole)

Application Efficiency 

(decimal) All 0.99 (ground)0.95 (aerial) -- –

Spray Drift Fraction 

(decimal) All

0.135 (aerial)

0.066(ground)

0.0 (seed 

treatment)

(USEPA, 

2013) Default spray drift assumptions

Application Date 

(day/month) All See Table 16 

and 18 --

Determined based on when crop 

was on field and times when 

maximum precipitation occurred in 

that month for foliar applications. 

Number of Applications

All See Table 16 

and 18

Proposed 

label --

Minimum Retreatment 

Interval -- --

IPSCND All Foliar: 3

Soil: 1 -- --

Hydrolysis Half-life (days)

TTR-UN

TTR Stable (0) MRID: 46235726

--

DFA Stable (0) No data --
29

Parameter (units) Residue Value (s) Source Comments

Aqueous Photolysis Halflife @ pH 7 (days)

TTR-UN

TTR 13.0 MRID 

48843669

The aqueous photolysis half-life 

input value was adjusted for 

continuous illumination as well as 

for latitude/season to reflect 

photolysis in summer sunlight at 

40o N latitude

DFA Stable (0) No data --

Water Half-life or Aerobic 

Aquatic Metabolism Halflife (days)

TTR-UN 791

MRID 

48843690, 

48843692

Represents the 90 percent upper 

confidence bound on the mean 

(791 and 2107) of two 

representative half-life values. 

Half-life values adjusted from 20o

C 

to 25o

C according to input 

parameter guidance.

TTR

2107

DFA

1282 MRID 

48843691

Represents the 90 percent upper 

confidence bound on the mean 

(809 and 555) of two 

representative half-life values. 

Half-life values adjusted from 20o

C 

to 25o

C according to input 

parameter guidance.

Benthic Half-life or

Anaerobic Aquatic 

Metabolism Half-life (days)

TTR-UN Stable (0)

MRID 

48843689

One available value was stable. 

The other value was 2470.

TTR 2576

Represents the 90 percent upper 

confidence bound on the mean 

(854) of two representative half-life 

values. Half-life values adjusted 

from 20o

C to 25oC according to 

input parameter guidance.

DFA Stable (0) No data --

Soil Half-life or Aerobic Soil 

Metabolism Half-life (days)

TTR-UN 525

MRIDs 

48843674, 

48843676, 

48843677, 

48843679, 

48843681, 

48843683

The 90 percent upper confidence 

bound on the mean of ten half-life 

values. No temperature conversion 

was performed. TTR 265

DFA 155 MRID 

48843679

The 90 percent upper confidence 

bound on the mean of three halflife values.

Foliar Degradation Rate All 0 d-1 Default --

Foliar Washoff Rate All 0.5 cm-1 Default --

Table 15. Modified Tier I Rice Model (for Estimating Exposure from Use on Cranberries) Input Parameters 

Input Parameter Value Comments Source

Application Rate

(lbs a.i./A)

TTR-UN: 0.37

DFA: 0.12

Maximum proposed annual application 

rate Proposed label
30

Input Parameter Value Comments Source

Soil-water Distribution 

Coefficient (Kd) (L/kg)

TTR-UN: 4.58

DFA: 0.17

Represents the mean Kd value (n=10 for 

parent; n=5 for DFA).

MRID 45405216

and 48843665

8 MODELING RESULTS

The uses on agricultural crops allow for ground, aerial, airblast, and seed treatment applications 

of a flowable material. EDWCs were estimated for aerial, ground, and seed treatment 

applications. The number of seasons per year was not specified on the label and 

flupyradifurone could be used for multiple seasons per year on one site. Therefore, simulations 

were run assuming two and three seasons per year, for the simulations that resulted in the 

highest EDWC for a single season per year. For the multi season per year simulations, the crop 

in the scenario was only present for one season a year; however, applications were assumed to 

occur over multiple seasons. Standard simulations assume spray drift will occur, some 

simulations were also run without spray drift, to be able to explore the possibility for mitigating 

with vegetative spray drift buffers.

TTR-UN and TTR

Estimated TTR-UN and TTR concentrations in surface water and groundwater used for drinking 

water are summarized in Table 16 and 17, respectively. PRZM-GW predicted the highest 

EDWCs for the foliar application at a rate of 0.18 lbs a.i./A with two applications, and a 7-day 

retreatment interval. The maximum single-day concentration of TTR-UN residues was 117 μg/L,

and the associated post-breakthrough average concentration was 102 μg/L. The maximum 

single-day TTR-UN concentration in groundwater for other uses ranged from 30 to 109 μg/L. 

Post- breakthrough average concentrations for these uses ranged from 17 to 96 μg/L. The 

average simulation breakthrough time for PRZM-GW ranged from 1346 to 3217 days (3.6 to 8.8 

years). These simulations indicate that it could take years following initiation of the use of 

flupyradifurone before the compound reaches groundwater (although preferential flow could 

substantially shorten such “breakthrough” times). Assuming two and three seasons per year 

resulted in EDWCs that were approximately two to three times those estimated for one season 

per year. Specifying the number of crop seasons per year on the label would reduce 

uncertainty in the EDWCs.

For surface water, the highest EDWCs were derived for the use on cranberries. A screening 

model (the Tier 1 rice model) was employed, which estimated an EDWC of 112 μg/L for the 

parent chemical. The value is calculated for residues of parent only, because the model does 

not account for degradation. This value represents both the acute and the chronic EDWC. 

Among uses other than cranberry, the simulated foliar application to cereal grains (0.18 lbs 

a.i./A, 2 applications, 7-day retreatment interval) resulted in the highest daily EDWC for TTR-UN 

in surface water: 46.1 μg/L. The highest annual average TTR-UN EDWC in surface water was 
31

13.9 μg/L, which resulted from a simulation of Crop Group 18 Nongrass Animal Feeds5. Acute 

TTR-UN EDWCs for other use scenarios ranged from 1.31 to 36.4 μg/L. Estimated annual 

average EDWCs ranged from 0.70 to 10.8 μg/L. Eliminating spray drift from the scenarios that 

resulted in the highest EDWC (other than the use on cranberry) had little impact on the 

calculated EDWC. EDWC with and without spray drift were within 1 μg/L of each other for 

PRZM/EXAMs runs for Crop Group 15 Cereal Grains and Crop Group 18 Nongrass Animal Feeds. 

This indicates that for these scenarios, the driver of the EDWCs was runoff. Assuming two and 

three seasons per year increased the EDWCs for surface water slightly compared with EDWCs

estimated assuming only one season per year. For example, maximum values with three 

seasons per year for all crops excluding cranberries the acute EDWC was 52.5 μg/L and the 

annual average EDWC was 22.3 μg/L. Cranberry uses are not expected to have multiple 

seasons per year.

Unextracted residues were conservatively assumed to comprise residues of concern in most of 

the modeling, though the extent to which unextracted residues are actually composed of 

residues of concern is not known. The scenarios that resulted in the highest EDWCs using halflives based on inclusion of unextracted residues were therefore also modeled using half-lives 

calculated based on values that excluded the unextracted residues (i.e., TTR residues of 

flupyradifurone plus M47 plus M48), thus employing the less conservative assumption that 

none of the unextracted residues represent residues of concern. The model inputs 

corresponding to both sets of assumptions (i.e., for parent only, and for parent plus 

unextracted residues) are shown in Tables 12 to 15. Not unexpectedly, the inclusion of 

unextracted residues in degradation half-life calculations did have an impact on EDWCs, 

especially for simulations with the PRZM-GW model, wherein concentrations increased by 

approximately 64 to 66%. 

Table 16. Comparison of EDWC for residues of TTR-UN versus TTR

Model

Acute EDWC Chronic EDWC

TTR-UN TTR % 

Difference TTR-UN TTR % Difference

PRZM-GW 117 71.5 64% 102 61.3 66%

PRZM/EXAMs* 46.1 28.3 63% 9.56 8.47 13%

PRZM/EXAMs** 23.2 23.4 -1% 13.9 14.5 -4%

% Difference = (TTR-UN EDWC- TTR EDWC)/TTR EDWC × 100

*TXcornOP (10-07) scenario; see Table 17

** CArangelandhayRLF_V2 (01-01) scenario; see Table 17

Difluoroacetic Acid

PRZM-GW predicted the highest DFA EDWCs for the seed treatment use with an assumed 

application rate of 0.37 lbs a.i./A. For use as a seed treatment, the maximum single-day 

 5 Crop Group 18 Nongrass Animal Feeds includes the following crops: Alfalfa; bean, velvet; clover ( Trifolium , 

Melilotus ); kudzu; lespedeza; lupin; sainfoin; trefoil; vetch; vetch, crown; vetch, milk (see 

http://ir4.rutgers.edu/other/CropGroup.htm).
32

concentration of DFA was 52 μg/L, and the associated post-breakthrough average 

concentration was 36 μg/L. The acute DFA EDWCs in groundwater for other uses ranged from 

42 to 46 μg/L. Post-breakthrough average concentrations for these uses ranged from 31 to 36

μg/L. The average simulation breakthrough time for PRZM-GW was 971 days (2.7 years). These 

simulations indicate that it could take relatively few years after use of flupyradifurone for DFA 

to reach groundwater (although preferential flow could substantially shorten such 

“breakthrough” times). All six standard scenarios were run, and of these the Wisconsin Sand 

scenario resulted in the highest EDWCs. Increasing the number of seasons per year to three 

increased the acute EDWC to 152 μg/L, and the post-breakthrough average EDWC to 114 μg/L. 

The use on cranberry resulted in the highest EDWCs (acute and chronic) for surface water, at 43 

μg/L. 

Table 17. Estimated Concentrations of Flupyradifurone plus M47 plus M48 (TTR) and plus unextracted residues 

(TTR-UN) in Surface Water Source Drinking Water.

Values with an asterisk were calculated for TTR. Values without an asterisk were calculated for TTR-UN. Purple 

values were the highest across scenarios. Bold black values were the highest value for the use site. Use Site (Application Timing for PRZM- GW) Single App. Rate lbs. a.i./Aa (kg a.i./ha) # of App Ret. Int. days App. Type6 Scenario Application Date (DD-MM)

EDWC for parent, M47, M48, and unextracted 

residues in μg/L

EDWC for parent, M47, and M48 in μg/L*

Aerial Ground

Acute Annual 

Average Acute Annual Average

Crop Group 15: 

Cereal Grains 

(except Rice)

0.18

(0.20) 2 7 F, A, 

G

IAcornSTD (01-06) 8.56 3.46 -- --

ILcornSTD (01-06) 13.9 4.86 -- --

INcornSTD (01-06 9.65 3.35 -- --

KSSorghumSTD (01-06) 15.8 5.54 -- --

MNcornSTD (01-07) 20.8 10.8 -- --

MScornSTD (10-04) 26.1 4.45 -- --

NCcornESTD (01-06) 16.7 5.31 -- --

NEcornSTD (01-05) 24.2 8.45

NDwheatSTD (01-06) 14.7 8.94 13.0 7.88

OHcornSTD (01-05) 9.74 3.77 -- --

ORwheatOP (01-12) 13.1 6.48 -- --

PAcornSTD (01-07) 13.4 6.03 -- --

TXcornOP (10-07)

46.1

45.2s

28.3*

47.7α

52.5β

9.56

9.03s

8.47*

12.8α

15.3β

-- --

TXsorghumOP (01-05) 25.6 7.60 -- --

TXwheatOP (01-05) 36.4 10.4 35.8 10.1

Cotton 0.18

(0.20) 2 7 F, A, 

G

CAcotton_WirrigSTD (01-01) 11.7 5.61 -- --

MScottonSTD (10-05) 17.9 3.34 -- --

NCcottonSTD (01-06) 18.7 5.42 -- --

TXcottonOP (01-05) 19.9 6.38 -- --

Peanut 0.18

(0.20) 2 7 F, A, G NCpeanutSTD (01-06) 12.5 4.10 -- --

Root Veg. 

(except 

Sugarbeet)

and 

Tuberous and 

0.18

(0.20) 2 7 F, A, 

G

FLcarrotSTD (01-09) 23.1 3.44 -- --

IDpotato_wirrigSTD (01-06) 4.17 2.56 -- --

MEpotatoSTD (01-06) 6.50 3.23 -- --

MIasparagusSTDv2 (01-09) 14.2 10.92 -- --

MNsurgarbeetSTD (01-06) 14.6 8.85 -- --
33

Use Site (Application Timing for PRZMGW)

Single App. Rate

lbs. a.i./Aa

(kg a.i./ha)

# of App

Ret. Int.

days

App. Type6

Scenario

Application Date

(DD-MM)

EDWC for parent, M47, M48, and unextracted 

residues in μg/L

EDWC for parent, M47, and M48 in μg/L*

Aerial Ground

Acute Annual 

Average Acute Annual Average

Corm Veg. ORmintSTD (15-04) 3.11 1.67 -- --

CAgarlicRLFV3 (01-01) 8.92 5.94 -- --

CArowcropRLF_V2 (01-02) 9.07 5.42 -- --

NCsweetpotatoSTD (01-06) 15.0 4.77 -- --

Leafy Veg.

(except 

Brassica) and

Brassica (Cole) 

Leafy Veg.

0.18

(0.20) 2 7 F, A, 

G

CAColeCropRLF (01-02) 19.0 9.19 -- --

FLcucumberSTD (01-09) 23.1 3.39 -- --

FLtomatoSTD_v2 (01-03) 18.5 2.94 -- --

CAlettuceSTD (16-02) 16.7 9.37 --- --

FLcabbageSTD (01-02) 13.7 3.58 -- --

Legume Veg.

(Succulent or 

Dried)

0.18

(0.20) 2 7 F, A, 

G

MIbeansSTD (01-09) 22.2 9.28 -- --

ORsnbeanssSTD (01-06) 7.70 2.67 -- --

CARowCropRLF_V2 (01-02) 9.07 5.42 -- --

Fruiting 

Vegetables

0.18

(0.20) 2 7 F, A

CAtomato_wirrigSTD (01-03) 7.14 4.73 -- --

FLtomatoSTD_v2 (01-03) 18.5 2.94 -- --

PAtomatoSTD (01-05) 7.56 3.19 -- --

FLpeppersSTD (01-09) 14.9 2.28 -- --

Cucurbit 

Vegetables

0.18

(0.20) 2 7 F, A

MOmelonSTD (10-04) 8.82 2.16 -- --

FLcucumberSTD (01-09) 23.1 3.39 -- --

NJmelonSTD (01-07) 12.4 5.01 -- --

MImelonSTD (01-07) 15.3 6.65 -- --

0.37

(0.40) 1 -- S, G FLcucumberSTD (01-09) 23.9 3.72

MImelonSTD (01-07) 7.34 3.29

Hops 0.14

(0.15) 1 0.14(0.15) F, A ORhopsSTD (01-04) 1.31 0.70

-- --

Citrus Fruit

0.18

(0.20) 2 7 F, A CAcitrus_WirrigSTD (01-01) 8.39 6.75 3.63s 2.75s

FLcitrusSTD (01-10) 31.5 5.51 -- --

0.37

(0.40) 1 -- S, G

CAcitrus_WirrigSTD (01-01) 4.34 3.43

FLcitrusSTD (01-10) 34.1

33.4s

6.59

6.42s

Pome Fruit 0.18

(0.20) 2 7 F, A

CAfruit_WirrigSTD (16-01) 8.60 6.96 -- --

NCapplesSTD (01-06) 8.90 3.39 -- --

ORappleSTD (01-10) 7.23 3.69 -- --

PAappleSTD_V2 (01-07) 11.1 5.92 -- --

Bushberry 0.18

(0.20) 2 7 F, A NYgrapesSTD (01-09) 13.8 7.63 -- --

ORberriesSTD (07-04) 3.23 1.76 -- --

Low Growing 

Berry 

(excluding 

Cranberry)

0.18

(0.20) 2 7 F, A

Flstrawberry_WirrigSTD (01-02) 17.3 3.94 -- --

ORberriesSTD (07-04) 3.23 1.76 -- --

CAstrawberry-noplasticRLF

(01-02) 19.5 8.24 -- --

Cranberry 0.18

(0.20) 2 7 F, A Modified Tier I Rice Model 112 112 -- --

Small Fruit 

Vine Climbing 

(except Fuzzy 

Kiwifruit)

0.18

(0.20) 2 7 F, A High from bushberry 13.8 7.63 -- --

CAwinegrapesRLF_V2 (01-03) 4.95 3.47 -- --

0.37

(0.40) 1 -- S, G

CAwinegrapesRLF (01-03) 3.36 2.06

NYgrapesSTD (01-09) 12.3 5.7

ORberriesSTD (07-04) 2.43 1.22

CAgrapes_WirrigSTD (01-02) 4.30 3.19

Tree Nut 0.18

(0.20) 2 7 F, A GApecansSTD (01-06) 15.7 3.12 -- --

Caalmond_WirrigSTD (16-01) 9.83 5.01 -- --
34

Use Site (Application Timing for PRZMGW)

Single App. Rate

lbs. a.i./Aa

(kg a.i./ha)

# of App

Ret. Int.

days

App. Type6

Scenario

Application Date

(DD-MM)

EDWC for parent, M47, M48, and unextracted 

residues in μg/L

EDWC for parent, M47, and M48 in μg/L*

Aerial Ground

Acute Annual 

Average Acute Annual Average

ORfilbertSTD (09-11) 11.6 5.94 -- --

Prickly Pear 0.18

(0.20) 2 7 F, G CAcitrus_WirrigSTD (01-01) 8.39 6.75 -- --

Nongrass 

Animal Feeds 

(Forage, 

Fodder, Straw, 

Hay)

0.18

(0.20) 2 7 F, A

ILalfalfaNMC (01-07) 14.0 5.50 -- --

MNalfalfaOP (01-06) 12.9 9.03 -- --

NCalfalfaOP (01-06) 12.9 4.08 -- --

PAalfalfaOP (01-07) 11.6 4.80 -- --

TXalfalfaOP (01-05) 30.0 9.37 -- --

CArangelandhayRLF_V2 (01-01)

23.2

20.7s

23.4*

32.2α

32.1β

13.9

12.2s

14.5*

20.4α

22.3β

-- --

Soybean Seed 

Treatment 

0.37

(0.40) 1 -- G MSsoybeanSTD (15-04) -- -- 13.5s 2.93s

Abbreviations: App=Application; A=aerial application; AB=airblast application; NJ/DE=Delmarva Sweet Corn; NC=NC cotton; 

WI=Wisconsin Corn; GA=Georgia Peanuts; Ave=average; Veg.=vegetables

* Results are for residues of flupyradifurone plus M47 plus M48. All other values reflect residues of flupyradifurone plus M47 

plus M48 plus unextracted residues. All results for surface water include, except the cranberry estimate, the correction of the 

model output with a 0.91 PCA value for total agriculture (USEPA, 2012b).

α Simulation for two seasons per year for residues of TTR-UN.

s Simulation without spray drift of TTR-UN.

β Simulation with three seasons a year of TTR-UN.

Table 18. Estimated Concentrations of Flupyradifurone Plus M47 Plus M48 (TTR) plus unextracted residues (TTRUN) in Groundwater Source Drinking Water

Bold values were the highest value for the use site.

Use Site (Timing

of App)

Single 

App. Rate

lbs. a.i./Aa

(kg a.i./ha)

# of 

App

Ret. 

Int.

Days

App. 

Type6

EDWC in μg/L

SCI-GROW PRZM-GW

Peak Scenario Daily 

Peak

Post 

Breakthrough 

Average

Ave

Breakthrough 

Time (Days)

Foliar Application

(10 days post 

emergence)

0.18

(0.20) 2 7 F, A 2.101.09*

NJ/DE 67.4 53.9 1346

FL Citrus 68.5 54.2 1357

FL Potato 18.5 17.0 3137

NC 69.6 56.3 2166

WI

117

71.5*

238α

352β

102

61.3*

208α

307β

3053

GA 29.9 26.7 3217

Soil Application 

(10 days postemergence)

0.18

(0.20) 2 7 F, A 2.101.09* WI 117 102 3053

0.37

(0.40) 1 -- G 2.16 WI 109 94.8 3053

Seed Treatment 0.37 1 -- G 2.16 WI 109 95.7 3053
35

Use Site (Timing

of App)

Single 

App. Rate

lbs. a.i./Aa

(kg a.i./ha)

# of 

App

Ret. 

Int.

Days

App. 

Type6

EDWC in μg/L

SCI-GROW PRZM-GW

Peak Scenario Daily 

Peak

Post 

Breakthrough 

Average

Ave

Breakthrough 

Time (Days)

(14 days preemergence)(0.40) 1.01*

4.31α

72.9*

172α

63.0*

150α

Abbreviations: App=Application; A=aerial application; AB=airblast application; NJ/DE=Delmarva Sweet Corn; NC=NC cotton; 

WI=Wisconsin Corn; GA=Georgia Peanuts; Ave.=average

* Results are for residues of flupyradifurone plus M47 plus M48. All other values reflect residues of flupyradifurone plus M47 

plus M48 plus unextracted residues.

α Simulation for two seasons per year.

β Simulation with three seasons a year of TTR-UN
36

Table 19. Estimated Concentrations of Difluoroacetic Acid (DFA) in Surface Water and Groundwater Source Drinking Water

Purple values were the highest across scenarios. Bold values were the highest value for across use sites for different exposure durations.

Use Site

Single 

App. Rate

lbs. a.i./Aa

(kg a.i./ha)

# of 

App

Ret. 

Int.

days

App. 

Type6

EDWC for DFA in μg/L

Surface Water1 Groundwater

SCI-GROW PRZM-GW

Acute Annual 

Average Peak Scenario Highest Daily Peak

Post 

Breakthrough 

Average

Average Simulation 

Breakthrough Time for 

PRZM-GW (Days)

Foliar Application

(10 days post 

emergence)

0.06

(0.07) 2 7 A

11.9 TX

6.53 CA

7.18α

8.51β

2.75 TX

4.34 CA

5.12α

7.74β

3.84 WI 41.5 30.7 971

0.12

(0.13) 1 -- A 10.2 TX 2.49 TX 3.84 WI 46.0 33.6 971

Soil Application 

(10 days postemergence)

0.06

(0.07) 2 7 G

4.83 CA

7.35 TX

8.18α

9.71β

3.16 CA

1.82 TX

2.43α

3.36β

3.84 WI

48.3

105α

152β

35.6

76.2α

114β

971

0.12

(0.13) 1 -- G 6.60 TX 1.66 TX 3.84 WI 46.0 33.6 971

Seed Treatment 

(14 days preemergence)

0.12

(0.13) 1 -- G 3.59 0.769 3.84 WI 51.791.5α

36.0

71.3α 971

Cranberry 0.06

(0.07) 2 7 A 43 43 3.84 WI 41.5 30.7 971

Abbreviations: App=Application; A=aerial application; AB=airblast application; NJ/DE=Delmarva Sweet Corn; NC=NC cotton; WI=Wisconsin Corn; GA=Georgia Peanuts

α Simulation for two seasons per year.

β Simulation for three seasons per year. 1

The TXcornOP scenario with a July 10th application date and the CArangelandhayRLF_V2 with a January 1st application date were used in the surface water simulations. An April 

15th application date and the MSsoybeanSTD scenario were used for the seed treatment simulation.

All results for surface water include, except the cranberry estimate, the correction with a 0.91 PCA value for total agriculture (USEPA, 2012b).
37

9 MONITORING DATA

Flupyradifurone is a proposed new chemical. There are no monitoring data currently available 

for flupyradifurone.

10 DRINKING WATER TREATMENT

There is no information available about the effects of drinking water treatment on 

flupyradifurone. The EDWCs in this assessment are representative of concentrations in drinking 

water source water (pre-treatment). For surface water, the conceptual model assumes that a 

pesticide reaches water via spray drift and/or surface runoff, and is instantaneously mixed 

throughout the receiving water body. Fate data show that flupyradifurone is stable to 

hydrolysis. Therefore, flupyradifurone will not degrade by hydrolysis during the time that 

elapses between intake of raw water and distribution of treated water to a consumer’s tap. 

Flupyradifurone does degrade via aqueous photolysis; therefore if ultraviolet light were used as 

a means of disinfection, degradation of flupyradifurone may occur; however, some of the 

degradates for this route of degradation have been identified as residues of concern. 

Additionally, the amount of UV radiation used is likely not sufficient to have a significant impact 

on degradation. Flupyradifurone degrades only slowly via aerobic aquatic metabolism;

therefore aerobic metabolism is not expected to be a significant loss mechanism for the 

compound during water treatment either. The most successful treatment process for removal 

of pesticides from drinking water is generally thought to be treatment with granular activated 

carbon (GAC), which because it is expensive may only be used in relatively large drinking water 

treatment facilities. The ability of GAC to remove organic compounds such as pesticides varies

with the properties of the chemical, the properties of the GAC, and the degree of saturation of 

GAC sorption sites (Badriyha et al., 2003; Zhao et al., 1999). Data on the sorption of 

flupyradifurone to GAC are not available; however, some loss of flupyradifurone due to 

sorption would be expected where GAC is used in drinking water treatment. 

11 UNCERTAINTIES

There are a number of uncertainties associated with this drinking water exposure assessment. 

These uncertainties include lack of a maximum annual application rate, presence of 

unextracted residues, and use of screening-level models and/or scenarios to calculate EDWCs.

Maximum application rates for flupyradifurone were provided on a seasonal basis. For most 

modeling, a single season was assumed per year. However, for many crops more than one 

season per year may occur. For example, there are commonly multiple seasons, or crops 

rotated with other crops in a single year, where leafy and fruiting vegetables are grown. In 

order to account for this uncertainty, EDWCs were also estimated assuming two and three 

seasons a year for the scenario resulting in the highest EDWC for surface water and 

groundwater. EDWCs estimated assuming two and three seasons per year were up to two to 

three times the EDWCs for one season per year. Specifying a maximum application rate on an 

annual basis for flupyradifurone on product labels would reduce this uncertainty in the EDWCs.
38

Table 20. Comparison of EDWC with 1 to 3 seasons per year

Peak or 

Chronic

TTR-UN EDWC μg/L TTR-UN 

3 season/ 1 

season

DFA EDWC μg/L DFA 

3 season/ 

1 season 1 season 2 season 3 season 1 season 2 season 3 season

Surface Water

peak 46.1 47.7 52.5 1.14 7.35 8.18 9.71 1.32

Chronic 13.9 20.1 22.3 1.60 4.34 5.12 7.74 1.78

Groundwater

peak 117 238 352 3.01 51.7 105 152 2.94

Chronic 102 208 307 3.01 36 76.2 114 3.17

One source of uncertainty in the assessment is the inclusion of unidentified, unextracted 

residues in the calculation of aerobic soil and aerobic aquatic metabolism half-lives. EDWCs for 

residues of TTR alone were 60 to 104% of EDWC for TTR with unextracted residues. The 

presence of unextracted residues contributes to uncertainty in EDWCs.

There is also uncertainty associated with the use of screening-level models. The EDWCs in this 

document are high-end and conservative estimates of exposure for vulnerable areas. These 

EDWCs would only occur in vulnerable areas, and are not expected to occur nationally across 

the United States. If dietary risks require refinement, higher-tiered models and modeling 

scenarios can be utilized upon request. 

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April 25, 2012).

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42

Appendix A. Modeling Output 

 SCIGROW

 VERSION 2.3

 ENVIRONMENTAL FATE AND EFFECTS DIVISION

 OFFICE OF PESTICIDE PROGRAMS

 U.S. ENVIRONMENTAL PROTECTION AGENCY

 SCREENING MODEL

 FOR AQUATIC PESTICIDE EXPOSURE

SciGrow version 2.3

chemical:flupyradifurone

time is 12/31/2013 15:44:15

------------------------------------------------------------------------

 Application Number of Total Use Koc Soil Aerobic

 rate (lb/acre) applications (lb/acre/yr) (ml/g) metabolism (days)

------------------------------------------------------------------------

 0.370 1.0 0.370 1.09E+02 349.0

------------------------------------------------------------------------

groundwater screening cond (ppb) = 2.16E+00 

************************************************************************

SciGrow version 2.3

chemical:flupyradifurone

time is 12/31/2013 15:53:14

------------------------------------------------------------------------

 Application Number of Total Use Koc Soil Aerobic

 rate (lb/acre) applications (lb/acre/yr) (ml/g) metabolism (days)

------------------------------------------------------------------------

 0.200 2.0 0.400 1.09E+02 349.0

------------------------------------------------------------------------

groundwater screening cond (ppb) = 2.33E+00 

************************************************************************

SciGrow version 2.3

chemical:flupyradifurone

time is 12/31/2013 15:56: 4

------------------------------------------------------------------------

 Application Number of Total Use Koc Soil Aerobic

 rate (lb/acre) applications (lb/acre/yr) (ml/g) metabolism (days)

------------------------------------------------------------------------

 0.200 2.0 0.400 1.09E+02 186.0

------------------------------------------------------------------------

groundwater screening cond (ppb) = 1.09E+00 

************************************************************************

SciGrow version 2.3

chemical:flupyradifurone

time is 12/31/2013 15:56:25

------------------------------------------------------------------------

 Application Number of Total Use Koc Soil Aerobic

 rate (lb/acre) applications (lb/acre/yr) (ml/g) metabolism (days)

------------------------------------------------------------------------
43

 0.370 1.0 0.370 1.09E+02 186.0

------------------------------------------------------------------------

groundwater screening cond (ppb) = 1.01E+00 

************************************************************************

 SCIGROW

 VERSION 2.3

 ENVIRONMENTAL FATE AND EFFECTS DIVISION

 OFFICE OF PESTICIDE PROGRAMS

 U.S. ENVIRONMENTAL PROTECTION AGENCY

 SCREENING MODEL

 FOR AQUATIC PESTICIDE EXPOSURE

SciGrow version 2.3

chemical:DFA

time is 1/ 2/2014 14:16:55

------------------------------------------------------------------------

 Application Number of Total Use Koc Soil Aerobic

 rate (lb/acre) applications (lb/acre/yr) (ml/g) metabolism (days)

------------------------------------------------------------------------

 0.060 2.0 0.120 7.30E+00 134.0

------------------------------------------------------------------------

groundwater screening cond (ppb) = 3.84E+00 

************************************************************************

SciGrow version 2.3

chemical:DFA

time is 1/ 2/2014 14:17:17

------------------------------------------------------------------------

 Application Number of Total Use Koc Soil Aerobic

 rate (lb/acre) applications (lb/acre/yr) (ml/g) metabolism (days)

------------------------------------------------------------------------

 0.120 1.0 0.120 7.30E+00 134.0

------------------------------------------------------------------------

groundwater screening cond (ppb) = 3.84E+00 

************************************************************************

PRZM EXAMS Run resulting in highest EECs

stored as flud.out

Chemical: Flupyradifurone

PRZM environment: 

TXcornOP.txt modified Thuday, 14 June 2007 at 10:24:04

EXAMS environment: 

ir298.exv modified Tueday, 26 August 2008 at 05:14:07

Metfile: w13958.dvf

modified Wedday, 3 July 2002 at 

08:06:24

Water segment concentrations (ppb)

Year Peak 96 hr 21 Day 60 Day 90 Day Yearly

1961 22.42 21.95 20.08 16.76 15.3 5.52
44

1962 63.12 61.74 56.99 47.8 42.09 14.63

1963 19.1 18.79 17.56 15.15 13.62 7.555

1964 5.97 5.851 5.573 4.805 4.559 2.655

1965 16.36 16.05 14.81 12.43 10.98 4.419

1966 29.33 28.94 26.58 22.99 20.44 8.666

1967 13.21 12.94 12.67 11.12 9.911 5.63

1968 13.15 12.88 12.11 10.24 9.054 4.213

1969 29.71 29.17 27.63 24.1 21.36 8.278

1970 9.29 9.105 8.495 7.331 6.534 4.873

1971 17.63 17.35 15.98 13.35 11.77 4.985

1972 7.349 7.198 6.746 5.91 5.297 3.121

1973 53.08 51.96 48.39 40.71 35.9 10.19

1974 21.49 21.12 19.66 16.83 15.05 10.54

1975 9.601 9.409 8.665 7.679 7.641 4.552

1976 14.48 14.19 13.04 11.38 10.16 4.747

1977 18.06 17.68 16.21 14.07 12.59 5.351

1978 15.24 14.92 13.67 11.72 10.46 5.581

1979 55.31 54.14 51.97 43.96 38.71 14.45

1980 12.85 12.65 11.85 10.29 9.285 5.998

1981 16.78 16.43 15.15 13.62 12.32 4.869

1982 6.52 6.412 5.979 5.146 4.62 3.11

1983 9.569 9.369 8.778 7.773 7.475 3.355

1984 6.386 6.296 5.925 5.094 4.508 2.633

1985 8.973 8.791 8.372 7.916 7.195 3.202

1986 19.02 18.62 17.2 14.39 12.7 5.214

1987 12.92 12.66 11.6 10.28 9.908 5.451

1988 5.992 5.869 5.512 4.88 4.605 2.911

1989 11.73 11.48 10.51 8.862 7.979 3.256

1990 9.932 9.726 9.058 7.799 7.162 3.795

Sorted results

Prob. Peak 96 hr 21 Day 60 Day 90 Day Yearly

0.032258 63.12 61.74 56.99 47.8 42.09 14.63

0.064516 55.31 54.14 51.97 43.96 38.71 14.45

0.096774 53.08 51.96 48.39 40.71 35.9 10.54

0.129032 29.71 29.17 27.63 24.1 21.36 10.19

0.16129 29.33 28.94 26.58 22.99 20.44 8.666

0.193548 22.42 21.95 20.08 16.83 15.3 8.278

0.225806 21.49 21.12 19.66 16.76 15.05 7.555

0.258065 19.1 18.79 17.56 15.15 13.62 5.998

0.290323 19.02 18.62 17.2 14.39 12.7 5.63

0.322581 18.06 17.68 16.21 14.07 12.59 5.581

0.354839 17.63 17.35 15.98 13.62 12.32 5.52
45

0.387097 16.78 16.43 15.15 13.35 11.77 5.451

0.419355 16.36 16.05 14.81 12.43 10.98 5.351

0.451613 15.24 14.92 13.67 11.72 10.46 5.214

0.483871 14.48 14.19 13.04 11.38 10.16 4.985

0.516129 13.21 12.94 12.67 11.12 9.911 4.873

0.548387 13.15 12.88 12.11 10.29 9.908 4.869

0.580645 12.92 12.66 11.85 10.28 9.285 4.747

0.612903 12.85 12.65 11.6 10.24 9.054 4.552

0.645161 11.73 11.48 10.51 8.862 7.979 4.419

0.677419 9.932 9.726 9.058 7.916 7.641 4.213

0.709677 9.601 9.409 8.778 7.799 7.475 3.795

0.741935 9.569 9.369 8.665 7.773 7.195 3.355

0.774194 9.29 9.105 8.495 7.679 7.162 3.256

0.806452 8.973 8.791 8.372 7.331 6.534 3.202

0.83871 7.349 7.198 6.746 5.91 5.297 3.121

0.870968 6.52 6.412 5.979 5.146 4.62 3.11

0.903226 6.386 6.296 5.925 5.094 4.605 2.911

0.935484 5.992 5.869 5.573 4.88 4.559 2.655

0.967742 5.97 5.851 5.512 4.805 4.508 2.633

0.1 50.743 49.681 46.314 39.049 34.446 10.505

Average of yearly 

averages: 5.791667

Inputs generated by pe5.pl - Novemeber 2006

Data used for this run:

Output File: flud

Metfile: w13958.dvf

PRZM scenario: TXcornOP.txt

EXAMS environment 

file: ir298.exv

Chemical Name: Flupyradifurone

Description

Variable 

Name Value Units Comments

Molecular weight mwt 288.68 g/mol

Henry's Law Const. henry 8.10E-13 atm-m^3/mol

Vapor Pressure vapr 1.30E-08 torr

Solubility sol 3200 mg/L

Kd Kd mg/L

Koc Koc 137 mg/L

Photolysis half-life kdp 13 days

Halflife

Aerobic Aquatic kbacw 791 days Halfife
46

Metabolism

Anaerobic Aquatic 

Metabolism kbacs 0 days Halfife

Aerobic Soil Metabolism asm 525 days Halfife

Hydrolysis: pH 7 0 days

Halflife

Method: CAM 2 integer See PRZM manual

Incorporation Depth: DEPI 0 cm

Application Rate: TAPP 0.2 kg/ha

Application Efficiency: APPEFF 0.95 fraction

Spray Drift DRFT 0.135 fraction of application rate applied to pond

Application Date Date 7-Oct dd/mm or dd/mmm or dd-mm or dd-mmm

Interval 1 interval 7 days Set to 0 or delete line for single app.

app. rate 1 apprate 0.2 kg/ha

Record 17: FILTRA

IPSCND 3

UPTKF

Record 18: PLVKRT

PLDKRT

FEXTRC 0.5

Flag for Index Res. Run IR Reservoir

Flag for runoff calc. RUNOFF total none, monthly or total(average of entire run)