1

OFFICE OF CHEMICAL SAFETY

AND POLLUTION PREVENTION

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON, D.C. 20460

PC Code: 288202

DP Barcode: D421158

MEMORANDUM

DATE: January 12, 2015

SUBJECT: Estimated Drinking Water Concentrations for Cyprodinil and its Metabolite 

CGA-249287 for the New Uses of the Chemical on Certain Stone Fruits (Crop 

Group 12-12), Certain Tropical Fruits, Artichoke, Cucumber (Greenhouse Use), 

and Pomegranate (Postharvest Dip)

FROM: José L. Meléndez, Chemist

Environmental Risk Branch 5

Environmental Fate and Effects Division (7507P)

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

Environmental Risk Branch 5

Environmental Fate and Effects Division (7507P)

TO: Erin Malone, Risk Manager Reviewer

Hope Johnson, Product Manager #21

Cynthia Giles-Parker, Branch Chief

Fungicide Branch

Registration Division (7505P)

AND: Thurston Morton, Chemist

Elissa Reaves, Branch Chief

Risk Assessment Branch 4

Health Effects Division (7509P)

This memo presents the Estimated Drinking Water Concentrations (EDWCs) for cyprodinil, an 

active ingredient of Vangard® WG, SwitchTM 62.5G, and Inspire SuperTM Fungicides, and its 

metabolite CGA-249287 (as per the Metabolism Assessment Review Committee’s decision 

document (MARC)), for the new uses of the chemical on certain stone fruits (Crop Group 12-

12), certain tropical fruits, artichoke, cucumber (greenhouse use), and pomegranate (postharvest 

dip). Based on a review of the use information, it was found that all the newly proposed crops 
2

have a similar or lower application rate than the maximum application rate of 0.47 lb a.i./A 

applied three times per year, or 1.4 lb a.i./A/year, previously modeled using the New York

grapes scenario. EDWCs for the new uses should be similar than those already calculated for 

grapes. Since previously modeled crops cover the new proposed crops, the results of the 

previous drinking waters assessment (DWA) can be used for the new uses; a new DWA is not 

required. In addition, this DWA provides EDWCs from the new model PRZM-GW, which had

not been modeled in the past. Appendix A provides the groundwater results obtained from 

PRZM-GW. A previous DWA, dated November 8, 2010 (DP Barcode D382086), involved only 

the products Vangard® WG and Switch® 62.5G Fungicides and the request to apply a maximum 

of two times aerially the products to most of the crops, and chemigation applications for several 

of the crops. The DWA provides structures and nomenclature of cyprodinil and its metabolite 

CGA-249287, as well as a summary of environmental fate for the chemical. In a 2011 DWA, a 

number of new uses were evaluated (DP Barcode D391853, dated November 4, 2011), but it 

referred back to the 2010 DWA for EDWCs.

The tier 2 aquatic models PRZM/EXAMS, and the models SCI-GROW and PRZM-GW were 

used to obtain EDWCs in surface water and groundwater, respectively. The acute EDWC in 

surface water is 34.8 μg/L for the total residues of cyprodinil plus CGA-249287. The chronic

EDWC in surface waters is 24.7 μg/L for the total residues of cyprodinil and CGA-249287. The 

cancer/chronic EDWC in surface waters is 16.4 μg/L for the total residues of cyprodinil and 

CGA-249287. All surface waters EDWCs were obtained using the New York grapes PRZM 

scenario. The PRZM-GW generated EDWC for the use on grapes, using the FL citrus surrogate 

scenario were 2.05 μg/L for the total residues of cyprodinil and CGA-249287 (acute) and 1.80 

μg/L for the total residues (chronic). For details on methods, characterization of results, 

uncertainties, etc., please, refer to the previous DWAs. Table 1 provides a summary of the Tier 2

modeled drinking water concentrations.

Table 1. Maximum Estimated Drinking Water Concentrations for the Use of Cyprodinil 

(expressed as total residues of cyprodinil plus its degradate CGA-249287)

DRINKING WATER SOURCE 

(MODEL USED) USE (rate modeled per year)

MAXIMUM ESTIMATED DRINKING WATER 

CONCENTRATION (EDWC) ( ppb)

Groundwater (PRZM-GW) FL citrus1(1.4 lb a.i.) Acute 2.05

Chronic 1.80

Surface water

(PRZM/EXAMS) NY grapes (1.4 lb a.i.)

Acute 34.8

Chronic 24.7

Cancer/Chronic 16.4

1 Scenario was used as a surrogate and run with the maximum application rate for grapes.

Should it be required, additional refinements may be available. For example, regional PCAs and 

typical use rates may be options to be used should it be requested by HED.

Identification of specific data gaps:

The environmental fate data base for cyprodinil is considered substantially complete; there are 

no new data available for this assessment. There is uncertainty with the aqueous photolysis 

study (MRID 43908422). It was carried out with natural (unsterilized) water. 

Phototransformation of cyprodinil in the irradiated samples followed a biphasic pattern, with 

slow transformation at the beginning. The possibility of microbial transformation is not ruled 
3

out. For modeling purposes, it was assumed that cyprodinil is stable to aqueous photolysis, 

which is a conservative assumption. Since the Problem Formulation for Registration Review 

was issued in 2012 (DP Barcode D393800), aerobic soil metabolism studies were submitted, 

which are currently in review.

Use information:

Three end-use products are involved in this DWA, as shown below. One product contains only 

cyprodinil, while two of the products have another active ingredient:

 Vangard® WG Fungicide (EPA Reg. No. 100-828), containing 75.0% cyprodinil A.I.

and 25.0% other ingredients

 Switch® 62.5G Fungicide (EPA Reg. No. 100-953) containing 37.5% cyprodinil A.I., 

25.0% fludioxonil A.I. and 37.5% other ingredients

 Inspire SuperTM Fungicide (EPA Reg. No. 100-1317) containing 24.1% cyprodinil A.I., 

8.4% difenoconazole A.I. and 67.5% other ingredients

Table 2 provides a summary of the current and proposed use information for the pesticide 

cyprodinil only (i.e., the table does not include the other two active ingredients). It also shows 

which crops have been modeled in the past. Generally, no more than two sequential applications 

are allowed as part of a resistance management strategy (unless otherwise stated for a crop). The 

label requires a buffer zone to protect lakes, reservoirs, rivers, permanent streams, marshes or 

natural ponds, estuaries and commercial fish ponds. For ground applications the buffer zone is 

75 ft; meanwhile, for aerial applications the buffer zone is 150 ft. A vegetative filter strip should 

be allowed within 10 ft of aquatic areas. Furthermore, other measures of precaution are required 

(e.g. applications when gusts or sustained winds exceed 10 mph are not allowed).

Several crops have been modeled in the past, using seasonal rates of 1.4 lb a.i./A/season. These 

include CA almond, NY grape, CA fruit and MI cherry. Additionally, other crops have been 

modeled using a seasonal rate of 1.3 lb a.i./A/season, which included OR snap bean, FL 

strawberry, MO melon, NC sweet potato, GA onion and PA tomato. The new uses involve 

similar rates: for the additional stone fruits the maximum seasonal rate is 1.4 lb a.i./A/season; for 

the additional tropical fruits it is 1.3 lb a.i./A/season; and for artichoke it is 1.32 lb a.i./A/season. 

The new use on cucumber is for greenhouses, and the use on pomegranate is for before and after 

storage; the uses on cucumber for greenhouses and pomegranate do not involve substantial 

exposure to wildlife.

Since previously modeled crops cover the new proposed crops, the results of the previous DWA 

can be used for the new uses.

Table 2. Summary of use information for cyprodinil, based on Vangard® WG (EPA Reg. No. 100-828), 

Switch® 62.5G (EPA Reg. No. 100-953) and Inspire Super® (EPA Reg. No. 1317) Fungicides. Changes or 

new crops are shaded blue. Scenarios that were previously modeled are shaded yellow.

Use

Max Single 

App Rate

(lb a.i./A)

Number of 

Apps at 

Max Rate

Annual App. 

Rate

(lb a.i./A/yr)

Min Interval

Between 

Apps. (days)

App 

Method

Pre-Harvest

Interval 

(days)

Almond (CA almond) 0.47 3 1.4 NS or 14 

(1)

G, A* 14
4

Use

Max Single 

App Rate

(lb a.i./A)

Number of 

Apps at 

Max Rate

Annual App. 

Rate

(lb a.i./A/yr)

Min Interval

Between 

Apps. (days)

App 

Method

Pre-Harvest

Interval 

(days)

Pistachio 0.33 4 1.3 14 G, A* 7

Tree Nuts (beech, Brazil nut, butternut, 

cashew, chestnut, chinquapin, filbert 

(hazelnut), hickory nut, macadamia nut, 

pecan, walnut (black and English))

0.47 3 1.4 NS

(2) 

G, A* 14

Citrus (lemon, lime) 0.33 1 0.33 N/A G 0

Grapes (NY Grape) (including cultivars, 

varieties, and/or hybrids of these; Amur river 

grape, hardy kiwifruit, maypop, schisandra 

berry; and muscadines, gooseberry for Inspire 

SuperTM only)

0.47 3 1.4 7 G, A*

(5)

7;

(14 days for

Inspire 

Super® only)

Kiwi 0.47 2 0.94 7 G, A* 0

Pome Fruits (CA fruit) (apples, azarole, 

crabapples, loquat, mayhaw, medlar, pears, 

Asian pear, quince, Chinese quince, Japanese 

quince, tejocote and cultivars, varieties and/or 

hybrids of these)

0.23 6 1.4 7 G, A*

(6)

0

Stone Fruits, Crop Group 12-12 (MI 

Cherry) (apricot, tart cherries, nectarines, 

peaches, plums, prunes, plumcot, Japanese 

apricot, capulin, black cherry, Nanking cherry, 

sweet cherry, Chinese jujube, beach plum, 

Canada plum, cherry plum, American plum, 

Chickasaw plum, Damson plum, Japanese 

plum, Klamath plum, prune plum, sloe, 

including all cultivars and/ or hybrids of these)

0.33**,

----------

0.23**,

----------

0.47** in 

CA

~5,

-------

6,

-------

up to 2 in 

CA (plus 

2 apps at 

0.23 lb/A)

1.4 N/S (3) G, A* 2

Tropical Fruits (Dragon fruit, lychee, 

longan, Spanish lime, rambutan, pulasan, 

avocado, black sapote, canistel, mamey 

sapote, mango, papaya, sapodilla, star apple, 

acerola, feijoa, guava, jaboticaba, passionfruit, 

starfruit, wax jambu)

0.33 4 1.3 7 G, A*

(5)

0

Beans (dried and succulent, except 

cowpeas) (OR Snap Bean) (garbanzo 

bean or chickpea, grain lupin bean, sweet 

lupin bean, white lupin bean, white sweet 

lupin bean, kidney bean, lima bean, mung 

bean, navy bean, pinto bean, snap bean, wax 

bean, fava bean, asparagus bean and

blackeyed pea)

0.33 4 1.3 7 G, A*, C 7

Strawberries (FL Strawberry) 

(including cultivars, varieties, and/or hybrids 

of these, bearberry, bildberry, cloudberry, 

mountries, partridgeberry)

0.47 3 at 0.43 1.3 7 G, A*, C

(5)

0

Berries: (including all cultivars and/ or 

hybrids of these)

Bushberries (aronia berry, black currant, 

blueberry high and low bush, Buffalo currant, 

Chilean guava, currant, edible honeysuckle, 

elderberry, European barberry, gooseberry, 

highbush cranberry, huckleberry, jostaberry, 

juneberry (Saskatoon berry), lingonberry, 

native currant, red currant, salal, sea 

buckthorn)

Caneberries (blackberry, loganberry, red and 

black raspberry, wild raspberry)

0.33 4 1.3 7 G, A*

(5)

0
5

Use

Max Single 

App Rate

(lb a.i./A)

Number of 

Apps at 

Max Rate

Annual App. 

Rate

(lb a.i./A/yr)

Min Interval

Between 

Apps. (days)

App 

Method

Pre-Harvest

Interval 

(days)

Brassica (cole) leafy vegetables

(broccoli, Chinese broccoli, broccoli raab, 

Brussel sprouts, cabbage, Chinese cabbage, 

cauliflower, cavalo broccolo, collards, kale, 

kohlrabi, mizuna, mustard greens, mustard 

spinach, rape greens and turnip greens)

0.33 4 1.3 7 G, A*, C 7

Cucurbit Crops (MO Melon)

(cantaloupe, cucumber*, guourds, honeydew, 

muskmelon, watermelon, chayote, Chinese 

waxgourd, Momordica spp. (bitter melon, 

balsam apple), pumpkin, squash and zucchini)

0.33 4 1.3 7 G, A*, C 1

Herbs, Dried and Fresh (angelica, balm, 

basil, borage, burnet, camomille, catnip, dried 

chervil leaves, chive, clary, coriander leaves 

{cilantro}, costmary, culantro leaves, curry 

leaves, dillweed, horehound, hyssop, lavender, 

lemongrass, lovage leaves, marigold, 

marjoram, nasturtium, dried parsley leaves, 

pennyroyal, rosemary, rue, sage, summer and 

winter savory, sweet bay, tansy, tarragon, 

thyme, wintergreen, woodruff and 

wormwood)

0.33 4 1.3 7 G, A*, C 7

Leafy Vegetables (except brassica) (head 

and leaf of lettuce, amaranth, arugula, chervil, 

edible chrysanthemum, corn salad, cress, 

dandelion, dock, escarole endive (escarole), 

New Zealand spinach, orach, parsley, 

purslane, radicchio, spinach, spinach vine)

Leafy Petioles (Cardoon celery; celery; 

Chinese celery; celtuce; Florence fennel; 

rhubarb; Swiss chard)

0.33 4 1.3 7 G, A*, C

(7)

0

Leaves of Root and Tuber 

Vegetables (NC Sweet Potato) (carrot, 

garden beet, sugar beet, edible burdock, 

cassava, celeriac, chicory, dasheen, parsnip, 

Oriental radish, rutabaga, black salsify, 

Spanish salsify, sweet potato, tanier, turnip 

rooted chervil, true yam)

0.33 4 1.3 (4) 7 G, A*, C 7

Root Vegetables (except sugar beet)

(edible burdock, carrot, celeriac, chicory, 

garden beet, ginseng, horseradish, parsnip, 

Oriental radish, rutabaga, black salsify, 

Spanish salsify, skirret, turnip, turnip root 

parsley, turnip rooted chervil)

0.33 4 1.3 (4) 7 G, A*, C 7

Bulb Onion (GA Onion) (Chinese 

onion, dry bulb onion, daylily bulb, Fritillaria 

bulb, garlic, great headed garlic, lily bulb, 

pearl onion, potato onion, serpent garlic, 

shallot)

Green Onion (Beltsville bunching onion, 

Chinese chive fresh leaves, fresh chive leaves, 

Fritillaria leaves, fresh onion, green onion, 

Hosta elegans, Kurrat, lady’s leek, leek, 

macrostem onion, shallot fresh leaves, tree 

tops onion, Welsh onion tops, wild leek, wild 

onion)

Onions Grown for Seed

0.47 3 at 0.43 1.3 7 G, A*, C

(7)

7
6

Use

Max Single 

App Rate

(lb a.i./A)

Number of 

Apps at 

Max Rate

Annual App. 

Rate

(lb a.i./A/yr)

Min Interval

Between 

Apps. (days)

App 

Method

Pre-Harvest

Interval 

(days)

Tomatoes and Fruiting Vegetables, 

Crop Group 8-10 (PA Tomato) 

(African eggplant, bush tomato, bell pepper, 

cocona, currant tomato, eggplant, garden 

huckleberry, Goji berry, groundcherry, 

Martynia, naranjilla, okra, pea eggplant, 

pepino, bell pepper, nonbell pepper, Roselle, 

scarlet eggplant, sunberry, tomatillo, tomato, 

tree tomato)

0.33 4 1.3 7 G, A*, C 0

Artichoke 0.328 4 1.32 14 G, A+, C 3

Watercress 0.33 4 1.3 7 G, C 0

Pomegranate (postharvest dip)*** 19.2 oz 

Switch 

62.5WG

(0.45 lb 

a.i.)/100 

gal water

2 N/A Once 

before and 

after 

storage

In line 

dip/ 

drench; 

dip for 

about 30 

seconds 

& drain

Postharvest

G = ground; A* = Aerial (maximum of two aerial applications allowed); A

+

= All aerial applications are allowed 

(i.e., no restrictions in the number of aerial applications for artichoke); C = Chemigation; NS = Not specified.

(1) For Vangard® WG one application at 5-10% bloom, 50-100% bloom and at petal fall. For Inspire Super®the 

minimum retreatment interval is 14 days and the maximum single application rate is 0.33 lb a.i./A.

(2) Apply when conditions are conducive to disease. It is noted that the supplemental labels for Switch® 62.5WG 

and Inspire Super®do not have this crop group.

(3) One application at bloom stage, second application at full bloom, in CA, two applications during the preharvest 

period.

(4) For radish, only 2 applications per crop and 4 applications per year.

(5) The supplemental label for Switch®62.5WG indicates that only one aerial application is allowed, and only in 

CA. Otherwise, only ground applications are allowed for the product.

(6) This crop group not included in the supplemental label for Switch®62.5G.

(7) The supplemental label for Inspire SuperTM does not have these crop groups.

*For cucumbers, applications in greenhouse are allowed, at 0.46 fl oz/1000 sq ft (no more than 50% of the sprays 

per crop). Applications in greenhouse are not assessed.

**The label for Inspire Super®allows applications at 0.33 lb a.i./A. The label for Vangard®allows up to two 

applications at 0.47 lb a.i./A in CA plus two applications at 0.23 lb a.i./A. Both labels allow up to two aerial 

applications.

***This use, to control Botrytis fruit rot and Gray mold, is not assessed since it does not involve substantial 

exposure to wildlife.
7

Appendix A. Tier 1 EDWCs for Groundwater - PRZM-GW

PRZM-GW v.1.07

Summary

The PRZM-GW generated EDWC for the use on grapes, using the FL citrus scenario were 2.05 

μg/L for the total residues of cyprodinil and CGA-249287 (acute) and 1.80 μg/L for the total 

residues (chronic).

Conceptual Model

Figure A-1 depicts the general groundwater scenario concept for estimating pesticide 

concentrations in drinking water as implemented in PRZM-GW. This conceptual model is based 

on a rural drinking water well beneath an agricultural field (a high pesticide use area) drawing 

from an unconfined, high water-table aquifer. 

Figure A-1. General Groundwater Scenario Concept for Estimating Pesticide 

Concentrations in Drinking Water as Implemented in PRZM-GW; The black line through 

the soil profile represents the decline in degradation with respect to the depth.

The depth of the well is site specific (i.e., scenario specific). The well extends into a shallow 

unconfined aquifer and has a well-screen1that starts at the top and extends down into the aquifer. 

The length of the well-screen represents the region of the aquifer where drinking water is 

collected. The well-screen length is well-specific and can be adjusted. Processes included in the 

conceptual model that influence pesticide transport through the soil profile include water flow, 

chemical specific dissipation and transportation parameters (i.e., degradation and sorption), and crop 

specific factors, including transpiration, pesticide interception and management practices.

 

1 A well screen is a filtering device that allows groundwater from unconsolidated and semi-consolidated aquifers to 

enter the well while at the same time keeping the majority of sand and gravel out of the well.
8

The following is a brief description of the PRZM-GW model. More information is available at 

http://www.epa.gov/oppefed1/models/water/index.htm#przm_gw (accessed 12/02/2014).

Tier 1 groundwater estimated drinking water concentrations (EDWCs) for a chemical, 

resulting from its use for bare ground pre-plant applications were derived with 

PRZM-GW (Pesticide Root Zone Model for Groundwater, version 1.07, March 6, 

2014), using the GW-GUI (Graphical User Interface, version 1.07, March 6, 2014). 

PRZM-GW is a one-dimensional, finite-difference model that estimates the 

concentrations of pesticides in groundwater. It accounts for pesticide fate in the crop 

root zone by simulating pesticide transport and degradation through the soil profile 

after a pesticide is applied to an agricultural field. PRZM-GW permits the assessment 

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 contaminations, are available for use with PRZM-GW for risk 

assessment purposes. In PRZM-GW simulations, each of these standard scenarios 

was used. PRZM-GW output values represent pesticide concentrations in a 

vulnerable groundwater supply that is located directly beneath a rural agricultural 

field.

Input Parameters for PRZM-GW and Results

Calculation of the application rates is explained in Table A-1.

Table A-1. Calculation of application rates for modeling of cyprodinil and its metabolite for 

the use on grapes

Chemical Species

% Maximum in Aerobic Soil Study Application Rate

(lb a.i./A)

Molecular 

Ratio

Modeled Application Rate 

Observed* Normalized (lb a.i./A)

Cyprodinil 100% 89.5% 0.421 1 0.421

CGA-249287 11.7% 10.5% 0.0492 0.662** 0.0327

Total 111.7% 100% 0.47

The shaded and bolded area provides the results used in modeling.

* Observed maximum values for parent and CGA 249287 in the aerobic soil metabolism studies

** CGA-249287 to cyprodinil molecular ratio = 149.20/ 225.29

For input parameters used in this model, refer to Table A-2.

Table A-2. Cyprodinil PRZM-GW Input Parameters for modeling applications of the 

chemical on grapes

PARAMETER (units) VALUE1SOURCE COMMENT

Application date 

(day/month)

30-05

Label. 

Applications are 

set to occur 

close to date of

maturation.

Delmarva emergence 10-04, crop maturation 30-

05, harvest 15-06

01-06 FL citrus crop emergence 01-01, crop maturation 

01-02, harvest 31-12

21-04 FL potatoes emergence 15-02, crop maturation 

01-05, harvest 01-06

01-08 GA coast emergence 01-05, crop maturation 01-

08, harvest 01-10

01-08 NC coast emergence 15-05, crop maturation 01-

08, harvest 01-11
9

PARAMETER (units) VALUE1SOURCE COMMENT

21-07 WI sand emergence 01-05, crop maturation 21-

07, harvest 20-10

Maximum Application Rate

(kg a.i./ha) 0.472

Label Maximum application rate is 0.421 lb a.i./A x 3 

applications at 7 day intervals. See Table A-1.

Number of Applications per 

Year 3

Retreatment Intervals 

(days) 7

Chemical Application 

Method (CAM) 2

Label Foliar

Incorporation Depth (cm) 0 ---

Air diffusion coefficient 

(cm2/day) 0.0 N/A Assuming no volatilization.

Vaporization enthalpy 

(kcal/mol) 0.0 N/A Assuming no volatilization.

Henry’s Law Constant 

(atm-m

3

/mol) 0.0 N/A Assuming no volatilization.

Partition Coefficient

(KOC; mL/gOC)

1,745 437090-47

Sorption is correlated with OC. Mean KOC value 

among four values ranging from 1550 to 2030 

ml/g.

Aerobic Soil Metabolism

Half-life (days)

32.4

43908425, 

43908426, 

43709045,

43709046

Represents the 90th percentile of the upper 

confidence bound on the mean of four half-life 

values: 39, 46 days at 20°C (corrected to 28, 33 

days at 25°C), and 22, 31 days at 25°C; mean = 

28.5 days; std. dev. = 4.80 days

Hydrolysis Half-life (days) 0 437090-44 Stable at pH 5, 7 and 9.

1 Parameters are selected as per “Guidance for Selecting Input Parameters for Modeling Pesticide Concentrations in Groundwater 

Using the Pesticide Root Zone Model” v.1.0, dated October 15, 2012.

Results are provided in Table A-3.

Table A-3. Cyprodinil Estimated Drinking Water Concentrations (EDWCs) resulting from 

the use of the chemical on grapes

Crop/Scenario

Highest Daily 

Value

(μg/L)

Post Breakthrough 

Average

(μg/L)

Average Simulation 

Breakthrough Time

(days)

Grapes/Tier I Delmarva19.28 x 10-58.5 x 10-522054

Grapes/Tier I FL citrus10.0276 0.0269 18210

Grapes/Tier I FL potatoes16.12 x 10-12 Incomplete2Incomplete2

Grapes/Tier I GA coast12.47 x 10-52.28 x 10-530062

Grapes/Tier I NC coast12.26 x 10-52.08 x 10-518381

Grapes/Tier I WI sand10.00317 0.00293 25728

1 This scenario was run with an extended weather file.

2 Incomplete despite running an extended weather file.

t t

t s

n

input

n

 



1 2

90 1

/

,

( )
10

Additionally, the degradate CGA-249287 was modeled separately.

Table A-4. CGA-249287 PRZM-GW Input Parameters for modeling applications of 

cyprodinil on grapes

PARAMETER (units) VALUE1SOURCE COMMENT

Application date 

(day/month)

30-05

Label. 

Applications are 

set to occur 

close to date of

maturation.

Delmarva emergence 10-04, crop maturation 30-

05, harvest 15-06

01-06 FL citrus crop emergence 01-01, crop maturation 

01-02, harvest 31-12

21-04 FL potatoes emergence 15-02, crop maturation 

01-05, harvest 01-06

01-08 GA coast emergence 01-05, crop maturation 01-

08, harvest 01-10

01-08 NC coast emergence 15-05, crop maturation 01-

08, harvest 01-11

21-07 WI sand emergence 01-05, crop maturation 21-

07, harvest 20-10

Maximum Application Rate 

(kg a.i./ha) 0.0367

Label Maximum application rate is 0.0327 lb a.i./A x 3 

applications at 7 day intervals. See Table A-1.

Number of Applications per 

Year 3

Retreatment Intervals 

(days) 7

Chemical Application 

Method (CAM) 1

Label Soil applied, it is a degradate.

Incorporation Depth (cm) 0 ---

Air diffusion coefficient 

(cm2/day) 0.0 N/A Assuming no volatilization.

Vaporization enthalpy 

(kcal/mol) 0.0 N/A Assuming no volatilization.

Henry’s Law Constant 

(atm-m

3

/mol) 0.0 N/A Assuming no volatilization.

Partition Coefficient

(Kd; mL/g)

3.97 43709047, 

43908431

Sorption is not correlated with OC. Mean Kd

value among the following values 0.31, 3.48, 

3.88, 5.23, and 6.97 ml/g.

Aerobic Soil Metabolism

Half-life (days) 216

43908425, 

43908426, 

43709045,

43709046

3X available value.

Hydrolysis Half-life (days) 0 437090-44 Assumed to be stable.

1 Parameters are selected as per “Guidance for Selecting Input Parameters for Modeling Pesticide Concentrations in Groundwater 

Using the Pesticide Root Zone Model” v.1.0, dated October 15, 2012.

Results are provided in Table A-5.

Table A-5. CGA-249287 Estimated Drinking Water Concentrations (EDWCs) resulting 

from the use of Cyprodinil on grapes

Crop/Scenario

Highest Daily 

Value

(μg/L)

Post Breakthrough 

Average

(μg/L)

Average Simulation 

Breakthrough Time

(days)

Grapes/Tier I Delmarva10.406 0.365 33042

Grapes/Tier I FL citrus12.02 1.77 17629
11

Crop/Scenario

Highest Daily 

Value

(μg/L)

Post Breakthrough 

Average

(μg/L)

Average Simulation 

Breakthrough Time

(days)

Grapes/Tier I FL potatoes10.345 0.301 15073

Grapes/Tier I GA coast10.516 0.43 25955

Grapes/Tier I NC coast10.0511 Incomplete2Incomplete2

Grapes/Tier I WI sand10.00949 Incomplete2Incomplete2

1 This scenario was run with an extended weather file.

2 Incomplete despite running an extended weather file.