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UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON, D.C. 20460

OFFICE OF

CHEMICAL SAFETY AND

POLLUTION PREVENTION

MEMORANDUM

DATE: April 26, 2010

SUBJECT: Tier I Estimated Drinking Water Concentrations of Fenpropathrin: IR-4 Petition 

for the Use of Fenpropathrin on Additional Tropical and Sub Tropical Fruits and 

for Tolerance for Tea (PC Code 127901, DP Barcode D368174).

FROM: José L. Meléndez, Chemist

Environmental Risk Branch V

Environmental Fate and Effects Division (7507P)

THROUGH: Mah T. Shamim, Ph.D., Chief

Environmental Risk Branch V

Environmental Fate and Effects Division (7507P)

TO: Laura Nollen, Risk Manager Reviewer

Barbara Madden, Review Manager #05

Daniel Rosenblatt, Branch Chief

Risk Integration, Minor Use and Emergency Response Branch

Registration Division (7505P)

AND Douglas Dotson, Ph.D., Chemist

Christina Swartz, Branch Chief

Registration Action Branch II

Health Effects Division (7509P)

This memo presents the Tier I Estimated Drinking Water Concentrations (EDWCs) for 

fenpropathrin, calculated using FIRST (surface water) and SCI-GROW (ground water) for use in 

the human health risk assessment. The registrant seeks to establish tolerances for use on 

additional (other than previously petitioned) tropical and sub tropical fruits, and tolerance only 

for tea.

The EFED has found that the scenario with the highest rate and minimum interval between 

applications is grapes (two applications at 0.4 lb a.i./A, at 7 day interval). This scenario was 

assessed in the previous drinking waters assessment (D295472, refer to Appendix A) and the 

Division is relying on it to cover the new uses.
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For surface water, the acute (peak) value is 10.3 ppb and the chronic (annual average) value is 

1.81 ppb. The groundwater screening concentration is 0.00480 ppb. These values generally 

represent upper-bound estimates of the concentrations that might be found in surface water and 

groundwater due to the use of fenpropathrin on grapes. Both models provide estimates suitable 

for screening purposes. Additional refinements can be developed should they be needed by 

HED. Should any questions arise, please, contact José L. Meléndez at melendez.jose@epa.gov.

Use Information:

Fenpropathrin is currently used on a variety of crops, including cotton, head and stem brassica, 

bushberries and currant, citrus, cucurbits, fruiting vegetables, grapes, peanuts, pome fruits, 

strawberries, peas, tree nuts and pistachio, barley, various tropical and sub tropical fruits 

(inedible peel, such as avocado, mango and papaya), bushberries, fruiting vegetables, peas, 

caneberries crop and olives. The registrant seeks to establish tolerances for use on various new

tropical and subtropical fruits (such as, but not limited to guava, acerola, passion fruit, starfruit, 

Spanish lime and cherimoya) (and tolerance only for tea). The proposed application rate for the 

new tropical and subtropical fruits is the same than for already registered tropical fruits (two 

applications at 0.4 lb a.i./A, at 14 day interval). Fenpropathrin may be applied by ground, 

airblast or aerial methods, but it may applied to tropical and subtropical fruits only via ground 

methods. Table 1-1 provides a summary table of all use patterns, with the new uses shaded blue, 

and the Tier I modeled use shaded gray.

Data gaps:

The database for fenpropathrin is considered adequate for drinking waters assessment. The 

mobility (batch equilibrium) study was found to be supplemental because Freundlich KF’s and 

KFOC’s could only be determined for the loam. Kd’s and KOC’s could not be determined for the 

silt loam sediment, and sandy loam, silt loam, sandy loam and clay loam soils at all 

concentrations. The possible need for additional data is being evaluated during the registration 

review process.
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Table 1-1. Summary use information for fenpropathrin, based on DANITOL® 2.4 EC Spray (Reg. No. 

59639-35) current and proposed labels. The new uses are shaded blue. The use pattern selected for 

modeling is bolded and shaded gray.

USE

SINGLE 

APP. 

RATE 

(lbs. a.i./A)

NUMBER 

OF APPS.

SEASONAL 

APP. RATE 

(lbs. a.i./A)

INTERVAL 

BETWEEN 

APPS. (days)

APP.

METHOD

PREHARVEST 

INTERVAL 

(days)

Tropical and subtropical fruits (guava, 

acerola, feijoa, jaboticaba, passion fruit, 

starfruit, wax jambu, lychee, longan, 

Spanish lime, pulasan, rambutan, sugar 

apple, atemoya, biriba, cherimoya, custard 

apple, ilama, soursop) 

0.3-0.4 2 0.8 14 G 1

Tropical and subtropical fruits (inedible 

peel, including but not limited to avocado, 

canistel, mango, papaya, sapodilla, black 

and mamey sapote, star apple)

0.3-0.4 2 0.8 14 G 1

Head and stem brassica (broccoli, brussel 

sprouts, cabbage, cauliflower, cavalo 

broccolo, Chinese broccoli-gal lon, Chinese 

cabbage-napa, Chinese mustard cabbage-gal 

choy, Kohlrabi, Brussels sprouts, 

cauliflower)

0.2-0.3 3-4 0.8 7 G, A 7

Citrus 0.2-0.4 2-4 0.8 10 G, Airblast, A 1

Cotton 0.15-0.3 3-5 0.8 7 G, A 21

Cucurbits (balsam apple, balsam pear, 

bitter melon, chayote, Chinese cucumber, 

Chinese waxgourd, citron melon, cucumber, 

edible gourd, gherkin, honeydew, 

Momordica spp., muskmelon, pumpkin, 

summer squash, watermelon, winter squash)

0.2-0.3 3-4 0.8 7 G, A 7

Fruiting vegetables (bell pepper, chili 

pepper, cooking pepper, eggplant, ground 

cherry-Physalis spp., pepino, pimento, sweet 

pepper, tomatillo, tomato)

0.15-0.2 4-5 0.8 7 G, A 3

Grape 0.1-0.4 2-8 0.8 7 G, A 21

Peanut 0.1-0.3 3-8 0.8 7 G, A 14

Pome fruit (apple, crabapple, loquat, 

mayhaw, quince, oriental pear, pear)

0.2-0.4 2-8 0.8 10 Airblast 14

Strawberry 0.2-0.4 2-8 0.8 30 G 2

Pea (English pea, garden pea, green pea, 

pigeon pea)

0.2 4 0.8 7 G, A 7

Currant 0.2-0.3 3 0.8 7 G 21
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Table 1-1. Summary use information for fenpropathrin, based on DANITOL® 2.4 EC Spray (Reg. No. 

59639-35) current and proposed labels. The new uses are shaded blue. The use pattern selected for 

modeling is bolded and shaded gray.

USE

SINGLE 

APP. 

RATE 

(lbs. a.i./A)

NUMBER 

OF APPS.

SEASONAL 

APP. RATE 

(lbs. a.i./A)

INTERVAL 

BETWEEN 

APPS. (days)

APP.

METHOD

PREHARVEST 

INTERVAL 

(days)

Bushberries (blueberry-highbush and 

lowbush, elderberry, gooseberry, 

huckleberry, juneberry, lingonberry, 

rabbiteye, salal)

0.2-0.3 2 0.6 14 G, A 3

Caneberries (blackberry-including 

bingleberry, boysenberry, dewberry, 

lowberry, marionberry, olallieberry and 

youngberry; loganberry; black raspberry; 

red raspberry)

0.2-0.3 2 0.6 14 G, A 3

Olive 0.2-0.3 3-4 0.8 14 G 7

Stone fruits (such as apricot, cherry, 

nectarine, peach, plum and prune)

0.2-0.4 2-4 0.8 10 Airblast 14

Tree nut (such as almond, beechnut, 

cashew, chestnut, chinquapin, filbert 

(hazelnut), hickory, macadamia, pecan, 

pistachio, walnut)

0.2-0.4 2-4 0.8 10 Airblast 14

Barley 0.2 1 0.2 N/A G 14
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APPENDIX A. Copy of Drinking Water Assessment Dated January 22, 2003

C O P Y

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON D.C., 20460

 OFFICE OF 

 PREVENTION, PESTICIDES AND

 TOXIC SUBSTANCES

January 22, 2003

MEMORANDUM

SUBJECT: IR-4 Tolerance Petition for the Use of Fenpropathrin (PC # 127901) on Bushberry

Crop Subgroup 13-B (DP Bar Code: D295472). Tier I Estimated Drinking Water 

Concentrations of Fenpropathrin.

TO: Shaja Brothers, PM Team Reviewer

Robert Forrest, Chief

Registration Division (7505C)

and Gary Bangs

Health Effects Division (7509C)

FROM: José Luis Meléndez, Chemist

Environmental Risk Branch V/EFED

THROUGH: Mah T. Shamim, Ph.D., Chief

Environmental Risk Branch V

Environmental Fate and Effects Division (7507C)

This memo presents the Tier I Estimated Drinking Water Concentrations (EDWCs) for 

fenpropathrin, calculated using FIRST (surface water) and SCIGROW (ground water) for use in 

the human health risk assessment. The registrant seeks to establish tolerances for use on 

bushberry crop (subgroup 13-B).

For surface water, the acute (peak) value is 10.3 ppb and the annual average value is 1.8 ppb. 

The groundwater screening concentration is <0.006 ppb. These values generally represent 

upper-bound estimates of the concentrations that might be found in surface water and 

groundwater due to the use of fenpropathrin on grapes, which represents the scenario with the 

highest application rate with the lowest interval between applications. Both models provide 

estimates suitable for screening purposes. Additional refinements can be developed should they

be needed by HED.
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Use of Fenpropathrin on Bushberry Crops (Subgroup 13-B):

The proposed petition for tolerance for the use of fenpropathrin is for use in the production of 

bushberry (subgroup 13B). The product used is Danitol 2.4 EC Spray (30.9% a.i.). It would be 

used on Blueberries (highbush and lowbush), Elderberries, Gooseberries, Huckleberries, 

Lingonberries, Juneberries, and Salal, for the control of Japanese Beetle, Blueberry Maggot, and 

Obliquebanded Leafroller. Two applications can be made with 14 day interval at a maximum of 

0.3 lb a.i./A/application, and not to exceed a seasonal application rate of 0.6 lb a.i./A. According 

to the submission (section B), the chemical can be applied by ground methods only.

Background Information on FIRST:

FIRST is a screening model designed to estimate the pesticide concentrations found in water for 

use in drinking water assessments. It provides high-end values on the concentrations that might 

be found in a small drinking water reservoir due to the use of pesticide. Like GENEEC, the 

model previously used for Tier I screening level, FIRST is a single-event model (one run-off 

event). It can also account for spray drift from multiple applications. FIRST takes into 

consideration the so called Index Drinking Water Reservoir by representing a larger field and 

pond than the standard GENEEC scenario. The FIRST scenario includes a 427 acres field 

immediately adjacent to a 13 acres reservoir, 9 feet deep, with continuous flow (two turnovers 

per year). The pond receives a spray drift event from each application plus one runoff event. 

The runoff event moves a maximum of 8% of the applied pesticide into the pond. This amount 

can be reduced due to degradation on field and the effect of binding to soil. Spray drift is equal 

to 6.4% of the applied concentration from the ground spray application and 16% for aerial 

applications.

FIRST also makes adjustments for the percent crop area. While FIRST assumes that the entire 

watershed would not be treated, the use of a PCA is still a screen because it represents the 

highest percentage of crop cover of any large watershed in the US, and it assumes that the entire 

crop is being treated. Various other conservative assumptions of FIRST include the use of a 

small drinking water reservoir surrounded by a runoff-prone watershed, the use of the maximum 

use rate, no buffer zone, and a single large rainfall.

Background Information on SCIGROW:

SCIGROW V.2.3 provides a groundwater screening exposure value to be used in determining 

the potential risk to human health from drinking water contaminated with the pesticide. Since 

the SCIGROW concentrations are likely to be approached in only a very small percentage of 

drinking water sources, i.e., highly vulnerable aquifers, it is not appropriate to use SCIGROW 

for national or regional exposure estimates.

SCIGROW estimates likely groundwater concentrations if the pesticide is used at the maximum 

allowable rate in areas where groundwater is exceptionally vulnerable to contamination. In most 

cases, a large majority of the use area will have groundwater that is less vulnerable to 

contamination than the areas used to derive the SCIGROW estimate.
7

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Estimated concentrations of chemicals with Koc values greater than 9995 ml/g are beyond the 

scope of the regression data used in SCI-GROW development. If there are concerns for such 

chemicals, a higher tier groundwater exposure assessment should be considered, regardless of the 

concentration returned by SCI-GROW.

Modeling Inputs and Results:

Tables 1 and 2 summarize the input values used in the model runs for FIRST 1.0 and 

SCIGROW, respectively. The lowest non-sand KD was used in FIRST. The median KOC value 

was used in SCIGROW. There was one available aerobic soil metabolism half-life for 

fenpropathrin. Three times the available half-life was used for the aerobic soil metabolism input 

in FIRST. The modeling results associated with maximum allowable rate per year (on peanuts, 

0.27 lb ai/A applied three times at 7 days intervals), are presented in Table 3. Attached to this 

memo are copies of the original printouts generated from FIRST and SCIGROW runs.

According to the label, there is a buffer zone of 25 feet between the treated fields and streams, 

ponds, lakes, rivers, springs, swamps, marshes, or irrigation canals containing water year around 

for ground applications, and 150 feet for aerial applications. If ultra low volume (ULV) 

application is made, the buffer zone should be increased to 450 feet.

Table 1. Environmental Fate and Other Input Parameters for the Estimation of 

Fenpropathrin using FIRST

Parameter Value Source

Water Solubility (25C) 0.0103 ppm MRID# 44370001

Hydrolysis Half-Life (pH 7) (stable) 0 MRID# 42599901

Aerobic Soil Metabolism Half-Life (3X available value) 456 days MRID# 42525902

Aerobic Aquatic Metabolism Half-life (2X aerobic soil input) 912 days NA

Aqueous Photolysis Half-Life (stable) 0 MRID# 42546402

Coefficient (Lowest non-sand Kd) 212 MRID#.s 42584101 

and 44370002

Pesticide is Wetted-In No Label

Method of Application aerial Label

PCA 0.87 Default for grapes

Depth of Incorporation (Broadcast) 0.0 in. Label
8

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Table 2. Environmental Fate Input Parameters for the Estimation of Fenpropathrin using 

SCIGROW.

Parameter Value Source

Organic Carbon Partition Coefficient (median KOC) 293000 MRID#’s 42584101 

and 44370002

Aerobic Soil Metabolism Half-Life (available value) 152 days MRID# 42525902

Table 3. Modeling Results for Use of Fenpropathrin on Grapes

Parameter Grapes Source

Application Method aerial Label

Application Rate 0.4 lb a.i./A Label

Applications Permitted per Year 2 Label

Application Interval 7 days N/A

FIRST 1.0 Peak Untreated Water Concentration 10.3 ppb N/A

FIRST 1.0 Annual Average Untreated Water Concentration 1.8 ppb N/A

SCIGROW Ground Water Concentration <0.006 ppb N/A
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Appendix I. SURFACE WATERS (FIRST) and GROUND WATERS OUTPUT 

RUNS FOR GRAPES

Estimated Surface Water Concentrations for Fenpropathrin

 RUN No. 1 FOR Fenpropathrin ON Grapes * INPUT VALUES * 

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

 RATE (#/AC) No.APPS & SOIL SOLUBIL APPL TYPE %CROPPED INCORP

 ONE(MULT) INTERVAL Kd (PPB ) (%DRIFT) AREA (IN)

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

 .400( .796) 2 7 212.0 10.3 AERIAL(16.0) 87.0 .0

 FIELD AND RESERVOIR HALFLIFE VALUES (DAYS) 

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

 METABOLIC DAYS UNTIL HYDROLYSIS PHOTOLYSIS METABOLIC COMBINED

 (FIELD) RAIN/RUNOFF (RESERVOIR) (RES.-EFF) (RESER.) (RESER.) 

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

 456.00 2 N/A .00- .00 912.00 912.00

 UNTREATED WATER CONC (MICROGRAMS/LITER (PPB)) Ver 1.0 AUG 1, 2001

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

 PEAK DAY (ACUTE) ANNUAL AVERAGE (CHRONIC) 

 CONCENTRATION CONCENTRATION 

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

 10.300 1.811

Estimated Ground Water Concentrations for Fenpropathrin

 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:Fenpropathrin

time is 1/20/2004 10:21:32

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

 Application Number of Total Use Koc Soil Aerobic

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

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

 0.400 2.0 0.800 2.93E+05 152.0

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

groundwater screening cond (ppb) = 4.80E-03*

*Estimated concentrations of chemicals with Koc values greater than 9995 

ml/g

are beyond the scope of the regression data used in SCI-GROW development.

If there are concerns for such chemicals, a higher tier groundwater exposure
10

assessment should be considered, regardless of the concentration returned

by SCI-GROW.

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