Page 2 of 29

Table of Contents

Executive Summary...................................................................................................................... 3

1.0 Exposure/Risk Assessment................................................................................................ 5

1.1 Hazard Concerns............................................................................................................ 5

1.2 Proposed Use Profile ...................................................................................................... 7

1.3 Existing Use Profile for Golf Course Turf ................................................................... 8

2.0 Occupational Exposures and Risk Estimates.................................................................. 9

2.1 Occupational Handler Exposure Data .............................................................................. 9

2.2 Occupational Handler Non-Cancer Risk Estimates...................................................... 10

2.2.1 Occupational Handler Exposure and Non-Cancer Risk Assumptions................. 10

2.2.2 Occupational Handler Non-Cancer Risk Estimate Calculations .......................... 11

2.2.3 Occupational Handler Non-Cancer Risk Estimates.......................................... 12

2.3 Occupational Handler Cancer Risk Estimates.......................................................... 14

2.3.1 Occupational Handler Exposure and Cancer Risk Assumptions ......................... 14

2.3.2 Occupational Handler Cancer Risk Calculations................................................... 14

2.3.3 Occupational Handler Cancer Risk Estimates ....................................................... 15

3.0 Occupational Postapplication Exposures and Risk Estimates.......................................... 18

3.1 Occupational Postapplication Exposure and Non-Cancer Risk Estimates................. 18

3.2 Occupational Postapplication Cancer Risk Estimates .................................................. 19

3.2.1 Occupational Postapplication Exposure and Cancer Risk Assumptions ............. 19

4.0 Residential Exposure ............................................................................................................ 20

4.1 Residential Handler Exposure ......................................................................................... 20

4.3 Use of TTR Data for Iprodione Post-application Exposure Assessments ................... 20

4.2 Residential Postapplication Exposure and Non-cancer Risk Estimates...................... 21

4.4 Residential Postapplication Exposure and Cancer Risk Estimates ............................. 24

5.0 Label Recommendation........................................................................................................ 27

APPENDIX A: IPRIDIONE DFR STUDY SUMMARY........................................................ 28
Page 3 of 29

Executive Summary

The Health Effects Division (HED) has conducted an occupational exposure assessment for the 

proposed new uses of the fungicide and nematicide active ingredient (ai) iprodione on cucurbits 

and fruiting vegetables. The new agricultural uses are for the product EnclosureTM 4 Flowable, 

a liquid concentrate formulation (41.6% iprodione; 4 lbs iprodione per gallon) and are intended 

as a nematicide. Iprodione applications can be made mechanically (groundboom) or by 

chemigation. This memorandum addresses the occupational exposure and risk from this label 

amendment and the revised residential exposure assessment that is needed for a aggregate risk 

assessment.

The new use label-required personal protective equipment (PPE) for mixers/loaders is longsleeved shirt, long pants, chemical-resistant footwear plus socks, chemical-resistant apron and 

chemical-resistant gloves.

Hazard Summary

Non-cancer short- and intermediate-term dermal and inhalation risk estimates in this assessment

are based on systemic effects observed in the rat pubertal assay at the Lowest Observed Adverse 

Effect Level (LOAEL) of 50 mg/kg/day.

The non-cancer level of concern is an MOE of <1000 for the short- and intermediate-term

exposure durations, respectively. The level of concern is based on uncertainty factors of 10x to 

account for intraspecies variability, a 10x for interspecies variability, and a factor of 10x to 

account for the LOAEL to NOAEL extrapolation for both short- and intermediate-term 

exposures.

Iprodione is also classified as a “Likely” human carcinogen based on a Q1* value assigned to 

iprodione based on testicular tumors (Leydig Cell) in rats of 4.4 x 10-2(mg/kg/day)-1; was used 

for assessing cancer risk. Additionally, iprodione has a degradate (3,5-DCA) with an established 

Q1*, although that Q1* value is not relevant to the exposure assessment on the new agricultural 

uses or the updated residential cancer risk assessment.

Occupational Handler Risk Summary

The occupational handler risk estimates were calculated using the label maximum application 

rate of 2 lb ai/acre, and assumptions regarding the agricultural equipment and work practices. 

For non-cancer risk estimates, inhalation and dermal exposures were combined since the 

endpoints were based on the same effect. For cancer risk estimates, inhalation and dermal 

exposures are assessed; dermal and inhalation exposures were combined. Based upon the 

proposed label PPE, non-cancer risk estimates were not of concern at the proposed label PPE. 

For the private grower scenario, cancer risk estimates range from 1.0 x 10-6to 1.0 x 10-5at the 

proposed label PPE. For the commercial grower scenario, cancer risk estimates range from 6.8 x 

10-6to 3.0 x 10-5at the proposed label PPE. 

Occupational Postapplication Risk Summary

Occupational short- and intermediate-term non-cancer dermal risk estimates were qualitatively 

assessed for postapplication activities. The proposed use pattern indicates pre-plant and soil 
Page 4 of 29

incorporated applications of iprdione. Therefore, the standard “foliar-based” transfer coefficient 

methodology does not apply. HED believes the proposed soil incorporation is expected to keep 

exposures low. Based on the Agency's current practices, a quantitative non-cancer occupational 

postapplication inhalation exposure assessment was not performed for iprodione at this time. 

Similarly, a review of the labeled use pattern indicates that because of negligible postapplication 

worker contact with treated soil, a quantitative postapplication cancer risk assessment is not 

necessary at this time. 

Restricted Entry Interval: Technical iprodione is classified as toxicity category III/IV for acute 

dermal toxicity, primary eye, and skin irritation. Under the WPS, active ingredients classified as 

acute toxicity categories III or IV for these exposure routes are assigned a 12-hour restricted 

entry interval. The proposed product label identifies a 24 hour restricted entry interval for 

curcurbits and fruiting vegetables.

Residential Exposure

HED assessed residential golf course turf exposure in this assessment in order to complete the 

aggregate assessment. While the agricultural uses of iprodione for curcurbits and fruiting 

vegetables are as a nematicide, the golf course use of iprodione assessment is as a fungicide. 

Iprodione can be applied to golf course turf where there is potential for postapplication 

residential exposure to golfers. Cancer and non-cancer postapplication risk estimates were 

calculated for non-occupational postapplication exposure to treated golf course turf. Non-cancer 

risk estimates for the residential golfer scenario ranged from 3,200 to 4,800; all the risk estimates 

are above the LOC of 1,000 and therefore, not of concern.

Cancer risk estimates for the golfer scenario range from 3.2x10-6to 1.8x10-5.

Human Studies Review

This risk assessment relies in part on data from studies in which adult human subjects were 

intentionally exposed to a pesticide or other chemical. These data, which include studies from 

the Pesticide Handlers Exposure Database Version 1.1 (PHED 1.1); the Agricultural Handler 

Exposure Task Force (AHETF) database, are subject to ethics review pursuant to 40 CFR 26, 

have received that review, and are compliant with applicable ethics requirements. For certain 

studies that review may have included review by the Human Studies Review Board. 

Descriptions of data sources as well as guidance on their use can be found at 

http://www.epa.gov/pesticides/science/handler-exposure-data.html and 

http://www.epa.gov/pesticides/science/post-app-exposure-data.html.

Label Recommendation

HED recommends the proposed product label should be modified to clarify that foliar 

application is prohibited for the proposed new uses on curcurbits and fruiting vegetables. While 

the crop specific parts of the label indicate clear use directions, other parts of the label appear to 

allow for aerial application (page 6 and other places) which is contrary to the crop specific 

curcurbit and fruiting vegetable uses on the proposed label.
Page 5 of 29

1.0 Exposure/Risk Assessment

The registrant requests new uses of iprodione on cucurbits and fruiting vegetables. This 

memorandum addresses the occupational exposure and risk from this label amendment. HED 

assessed post-application residential golf course turf exposure in this assessment in order to 

complete the aggregate assessment.

1.1 Hazard Concerns

Acute Toxicity

The results of acute toxicity testing are given in Table 1.1a. These results indicate that technical 

iprodione has low to moderate acute toxicity, is a mild eye irritant, and is not a dermal sensitizer.

Table 1.1a. Acute Toxicity of Iprodione

Guideline 

No. Study Type MRID Results Toxicity Category

870.1100 Acute Oral –rat 423063-01 LD50 = 4468 mg/kg III

870.1200 Acute Dermal – rabbit 405676-01 LD50 > 2000 mg/kg III

870.1300 Acute Inhalation - rat 429461-01 LC50 >5.16 mg/L IV

870.2400 Primary Eye Irritation – rabbit 418673-01 Mild irritant III

870.2500 Primary Skin Irritation – rabbit 418673-02 Not an irritant IV

870.2600 Dermal Sensitization – guinea pig 405676-02

425246-01

Not a dermal sensitizer N/A

Toxicological PODs Used for Risk Assessment

A summary of the toxicological points of departure (PODs) that are relevant to occupational 

exposure is included in Table 1.1b. 

A single endpoint was selected to cover the dermal and inhalation short- and intermediate-term 

occupational exposure scenarios. The endpoint for the occupational exposure scenarios was 

selected from the male rat pubertal assay (MRID 48279201) where the LOAEL is 50 mg/kg/day, 

based on reduced serum testosterone. The 69 kg bodyweight is appropriate to use for the 

occupational assessment because the endpoint is an in utero effect occurring during prenatal 

exposure.

HED’s level of concern for non-cancer risk estimates is defined by the uncertainty factors that 

are applied to the assessment. The level of concern for short- and intermediate-term iprodione 

occupational exposures is 1000, based on the inter- and intra-species factors as well as a 10x 

uncertainty factor for the lack of a NOAEL in the study.
Page 6 of 29

For the non-cancer residential exposure assessment, the standard inter- and intra-species factors 

are applicable. Additionally, HED recommends that the 10X FQPA safety factor be retained for 

the short- and intermediate-term dermal and inhalation exposure points of departure (for the 

protection of infants and children), based on the LOAEL to NOAEL extrapolation.

Therefore the level of concern for residential exposure is an MOE of <1,000.

Based on the available toxicity database and the Agency’s current practices, the inhalation risk 

for iprodione was assessed using an oral study. The toxicity sought expert advice and input on 

issues related to this route to route extrapolation approach (i.e., the use of oral toxicity studies for 

inhalation risk assessment) from its Federal Insecticide, Fungicide, and Rodenticide Act 

Scientific Advisory Panel (SAP) in December 2009. The Agency received the SAP’s final report 

on March 2, 2010 (http://epa.gov/scipoly/meetings/20091220109meeting.html). The Agency is 

in the process of evaluating the SAP report and may, as appropriate, re-examine and develop 

new policies and procedures for conducting inhalation risk assessments, including route to route 

extrapolation of toxicity data. If any new policies or procedures are developed, the Agency may 

revisit the need for an inhalation toxicity study for iprodione and/or a re-examination of the 

inhalation toxicity risk assessment.

In accordance with the EPA Proposed Guidelines for Carcinogen Risk Assessment (April 10, 

1996), the Cancer Assessment Review Committee classified Iprodione as a "likely" human 

carcinogen based on the combined hepatocellular adenomas/carcinomas in mice and testicular 

tumors in male rats with a linear low dose extrapolation approach and a 3/4s interspecies scaling 

factor for human risk characterization. The CARC determined that for the Leydig cell tumors in 

male rats, the Q1* is 4.39 x 10-2(selected by HED’s CARC Committee; TXR 0054534, 3/22/07). 

HED policy doesn’t define a “level of concern” when evaluating cancer risk estimates. The 

cancer risk estimates are presented based on the Q1* value for OPP risk managers to evaluate 

and mitigate as needed.
Page 7 of 29

Table 1.1b. Toxicological PODs for Occupational Exposure Assessment of Iprodione

Exposure Scenario Point of Departure 

(POD)

Uncertainty 

Factors Study and Toxicological Effects

Dermal Short-Term 

(1-30 days)

Dermal 

Intermediate-Term

Inhalation ShortTerm (1-30 days)

Inhalation 

Intermediate- Term

LOAEL = 50 

mg/kg/day

Dermal absorption

factor = 5%

Since no inhalation 

toxicity data are 

available, toxicity by the 

inhalation route is 

considered to be 

equivalent to toxicity by 

the oral route of 

exposure

UFA 10x

UFH 10x

UFLOAEL→NOAEL =10X

Co-critical studies

Male pubertal toxicity (rat)

MRID 48279201

LOAEL = 50 mg/kg/day, based on 

significant, dose-related reductions in 

serum testosterone levels (↓73%)

Chronic oral toxicity (rat) 

MRID 42637801/42787001

LOAEL = 12.4 mg/kg/day, based on 

increases in generalized enlargement of 

the cells of the zona glomerulosa in males 

and females, in fine vacuolation of the 

zona fasciculata and in generalized fine 

vacuolation of the zone reticularis in 

males in the adrenal cortex, an increased 

incidence of interstitial cell hyperplasia, 

reduced spermatozoa in the epididymides, 

reduced secretion of the seminal vesicles, 

increased hemosiderosis in the spleen in 

females, and increased liver weight.

NOAEL = 6.1 mg/kg/day

Inhalation ShortTerm (1-30 days)

Inhalation 

Intermediate- Term

LOAEL = 50 

mg/kg/day

UFA 10x

UFH 10x

UFLOAEL→NOAEL =10X

Male pubertal assay (rat)

MRID 48279201

LOAEL = 50 mg/kg/day, based on reduced serum 

testosterone levels

Dermal Absorption 

Factor

5 percent of the oral dose Based on the value measured at 10 hours in a 

dermal absorption study (MRID 43535003).

Carcinogenicity Q1* = 4.4 x 10-2

(mg/kg/day)-1

Iprodione is classified as a “Likely” human 

carcinogen, based on findings in the Rat Leydig 

cells (CARC-based Q1*)

Point of Departure (POD) = A data point or an estimated point that is derived from observed dose-response data and used to mark the beginning 

of extrapolation to determine risk associated with lower environmentally relevant human exposures. LOAEL = lowest observable adverse effect 

level. UF = uncertainty factor. UFA = extrapolation from animal to human (interspecies). 

1.2 Proposed Use Profile

The proposed new uses for the product EnclosureTM 4 Flowable, a liquid concentrate formulation 

(41.6% iprodione; 4 lbs ai per gallon), are on cucurbits and fruiting vegetables. The maximum 

application rate allowed on this label for cucurbits and fruiting vegetables is 4 pints of 

EnclosureTM 4 Flowable per acre (2 lb ai/acre) per application and up to 3 applications are 
Page 8 of 29

allowed per season. The maximum application rate per season is 6 pints per acre (3 lb 

ai/A/season). The pre-harvest interval (PHI) for cucurbits and fruiting vegetables is 14 days (the 

final application can be made up to 14 days before harvest). Application consists of a soil 

directed pre-plant or post-plant mechanical incorporation. The application timings and methods 

are described below.

Cucurbits and fruiting vegetables, transplanted crops: The application is specified to be a 

preplant and post plant soil treatment. For transplanted crops, the label specifies that the 1st

application should be made 4-7 days prior to transplant and that the product should be 

thoroughly incorporated (mechanically or through drip irrigation) into the bed at least 3-5 inches 

deep. The 2nd application is specified to be made through drip chemigation 7- 10 days after 

transplanting. The 3rd application is specified to be made through drip chemigation 12-14 days 

after the 2nd application. 

Cucurbits and fruiting vegetables, seeded crops: The application is specified to be a pre plant 

and post plant soil treatment. For seeded crops, the label specifies that the 1st application be 

made 4-7 days prior to seeding. The product should be thoroughly incorporated (mechanically 

or through drip chemigation) into the bed at least 3-5 inches. The 2nd application is specified to 

be made through drip chemigation 10-14 days after seedling emergence. The 3rd application is 

specified to be made through drip chemigation 12-14 days after the 2nd application.

The label specifies that for nematode supplemental control, the product should be applied 

through drip chemigation 14-21 days after transplanting, and that subsequent applications 

through drip chemigation should be made on 14-day intervals. 

The label specifies that when the high rate of 4 pints per acre is used, only one subsequent 

application at 2 pints per acre is allowed. This application should be made 7-10 days after 

transplanting or 10-14 days after seedling emergence.

1.3 Existing Use Profile for Golf Course Turf

HED conducted a cancer risk assessment based on non-occupational exposure to treated golf 

course turf to contribute an aggregate human health risk assessment. A variety of existing 

product labels for turf were reviewed. Because iprodione can be used to prevent disease or to 

control disease infestation, product labels indicate a range of potential application rates 

depending on seasonality or disease pressure. Some product labels have differential application 

rates for golf course greens and fairways. For example, 9198-229 indicates an application rate of 

8.2 and 5.5 lbs ai/A for tees and greens and fairways, respectively. Granular formulations are to 

be applied using a light rate (1.4 lb ai/acre) to prevent certain fungi such as pink or gray snow 

mold or leaf spot. Other liquid product labels indicate a normal (2.7 lb ai/acre) to heavy 

application rate (4.1 lb ai/acre) to control fungi such as leaf spot, brown patch and red leaf spot 

(representative label: EPA Reg. No. 538-159).
Page 9 of 29

2.0 Occupational Exposures and Risk Estimates

HED uses the term handlers to describe those individuals who are involved in the pesticide 

application process. HED believes that there are distinct job functions or tasks related to 

applications and exposures can vary depending on the specifics of each task. Job requirements 

(amount of chemical used in each application), the kinds of equipment used, the target being 

treated, and the level of protection used by a handler can cause exposure levels to differ in a 

manner specific to each application event. 

Tasks associated with occupational pesticide handlers are categorized using one of the following 

terms:

Mixers and/or Loaders: these individuals perform tasks in preparation for an application. 

For example, mixers/loaders would mix and prepare the nematicide product prior to 

application.

Applicators: these individuals are involved in the pesticide application process (they do 

job functions related to a pesticide application event). These individuals would complete 

the product application. 

The following occupational handler exposure scenarios were assessed: 

1 – Mix/Load Liquid for Chemigation

2 – Mix/Load Liquid for Groundboom Application

3 – Apply spray by Groundboom Sprayer

A chemical can produce different effects based on how long a person is exposed, how frequently 

exposures occur, and the level of exposure. HED classifies exposures from 1 to 30 days as shortterm and exposures 30 days to six months as intermediate-term. HED completes both short- and 

intermediate-term assessments for occupational scenarios in all cases because these kinds of 

exposures are likely and acceptable use/usage data are not available to justify deleting 

intermediate-term scenarios. Based on use data and label instructions, HED believes that 

occupational exposures may occur over a single day or up to weeks at a time for many usepatterns and that intermittent exposure over several weeks may also occur. Some applicators 

may apply these products over a period of weeks, because they are commercial applicators who 

are completing multiple applications for multiple clients. Long-term (greater than six months) 

handler exposures are not expected for iprodione based on the proposed use pattern.

Occupational handler exposure assessments are completed by HED using different levels of risk 

mitigation. Typically, HED uses a tiered approach evaluating various levels of personal 

protective equipment. This approach is used to ensure that the lowest level of risk mitigation that 

provides adequate protection is selected, since the addition of PPE and engineering controls 

involves an additional expense to the user and (in the case of PPE) also involves an additional 

burden to the user due to decreased comfort and dexterity and increased heat stress and 

respiratory stress.

2.1 Occupational Handler Exposure Data
Page 10 of 29

It is the policy of HED to use the best available data to assess handler exposure. Sources of 

generic handler data, used as surrogate data in the absence of chemical-specific data, include the 

Pesticide Handlers Exposure Database Version 1.1 (PHED 1.1), the Agricultural Handler 

Exposure Task Force (AHETF) database, the Outdoor Residential Exposure Task Force 

(ORETF) database, or other registrant-submitted occupational exposure studies. Some of these 

data are proprietary (e.g., AHETF data), and subject to the data protection provisions of FIFRA. 

The standard values recommended for use in predicting handler exposure that are used in this 

assessment, known as “unit exposures”, are outlined in the “Occupational Pesticide Handler Unit 

Exposure Surrogate Reference Table” (http://www.epa.gov/opp00001/science/handler-exposuretable.pdf), which, along with additional information on HED policy on use of surrogate data, 

including descriptions of the various sources, can be found at 

http://www.epa.gov/pesticides/science/handler-exposure-data.html.

The appropriate unit exposure data are listed below in Table 2.1.

Table 2.1. Iprodione Occupational Handler Dermal and Inhalation Unit Exposures used for 

Non-Cancer and Cancer Risk Assessments

Exposure 

Scenario

Dermal Unit Exposure (mg/ lb ai) Inhalation Unit Exposure (mg/ lb ai)

BaselineA Single Layer 

plus GlovesB

Double Layer 

Plus GlovesC

Engineering 

ControlD

Baseline

E

PF5 

Respirator

PF10 

Respirator

Engineering 

ControlF

Mixer/Loader Scenarios

Mixing/Loading 

Liquids for 

Chemigation 

Application

0.22 0.0376 0.0291

Closed 

System:

0.0086

0.000219 0.000044 0.000022

Closed System: 

0.000083

Mixing/Loading 

Liquids for 

Groundboom 

Application

0.22 0.0376 0.0291

Closed 

System:

0.0086

0.000219 0.000044 0.000022

Closed System: 

0.000083

Applicator Scenarios

Applying Spray via

Open Cab 

Groundboom

0.0786 0.0161 0.0126

Enclosed 

Cab: 

0.0051

0.00034 0.00007 0.00003

Enclosed Cab: 

0.000043

A. Baseline dermal unit exposures represent long pants, long sleeved shirts, shoes, and socks, no gloves. 

B. Single Layer plus gloves (minimum PPE) dermal unit exposure represent long pants, long sleeved shirts, shoes, socks and chemical-resistant 

gloves. 

C. Double layer plus gloves (Maximum PPE) dermal unit exposure represent long pants, long sleeved shirt, shoes, socks, coveralls, and chemical 

resistant gloves. 

D. Engineering control includes closed mixing and loading for mixer/loaders and an enclosed cab for applicators. 

E. Baseline inhalation unit exposures represent no respirator protection (baseline). 

F. Engineering control includes closed mixing and loading for mixer/loaders and an enclosed cab for applicators. 

2.2 Occupational Handler Non-Cancer Risk Estimates

2.2.1 Occupational Handler Exposure and Non-Cancer Risk Assumptions

The assumptions and factors used in the risk calculations include:

The application rate is 2 lbs ai per acre [proposed curcurbit/vegetable use]. 
Page 11 of 29

Unit exposure data are outlined above in Table 2.1.

The area treated per day is 350 acres for chemigation application short/intermediate-term 

exposures and 80 acres for groundboom application short/intermediate-term exposures. 

These values were derived from ExpoSAC policy 3.1.

The body weight for short- and intermediate-term non-cancer exposure assessment is 69

kg because the effects are based on developmental effects.

2.2.2 Occupational Handler Non-Cancer Risk Estimate Calculations

Average Daily Dose (ADD): Potential daily exposures for occupational handlers were calculated 

using the following formula:

Daily Exposure (mg ai /day) = UE (mg ai / lb ai) * AR (lb ai /A) * AT (A /day)

Where:

UE = Unit Exposure (from PHED),

AR = maximum application rate according to proposed label, and

AT = daily acres treated.

The daily doses were calculated using the following formula:

Average Daily Dose (mg ai/kg/day) = [Daily Exposure (mg ai/day) * Absorption (%)]

Body Weight (kg)

Margin of Exposure: Non-cancer inhalation risk estimates for each application handler scenario 

are calculated using a Margin of Exposure (MOE), which is a ratio of the toxicological endpoint 

to the daily dose of concern. Risk estimates were calculated for inhalation exposure, as there 

was no dermal endpoint. 

MOE = PoD (typically a NOAEL or LOAEL in mg/kg/day) / ADD (mg/kg/day)

Where:

MOE = Margin of Exposure: value used by HED to represent risk or risk estimates (unitless),

PoD = Point of Departure,

NOAEL = No Observed Adverse Effect Level: Dose level in a toxicity study, 

LOAEL = Lowest Observed Adverse Effect Level; and

ADD = Average Daily Dose: the absorbed dose received from exposure to a pesticide in a given scenario.

A combined dermal and inhalation MOE was calculated to show combined dermal and 

inhalation risk estimates. Combined risks of concern are identified by an MOE < 1000. 

Combined MOE = Dermal and Inhalation PoD (typically a NOAEL/LOAEL in mg/kg/day) 

 Dermal ADD (mg/kg/day) + Inhalation ADD (mg/kg/day)

Where:

MOE = Margin of Exposure: value used by HED to represent risk or risk estimates (unitless),

PoD = Point of Departure,

NOAEL = No Observed Adverse Effect Level (mg/kg/day): Dose level in a toxicity study, where 

no observed adverse effects occurred in the study, and
Page 12 of 29

ADD = Average Daily Dose (mg/kg/day): the absorbed dose received from exposure to a 

pesticide in a given scenario.

2.2.3 Occupational Handler Non-Cancer Risk Estimates

The occupational handler non-cancer risk estimates are included in Table 2.2.3. Combined 

MOEs for the handler non-cancer risk estimates exceed the level of concern of 1000 with the 

proposed label personal protective equipment (i.e., gloves, no respirator), which means that the 

non-cancer risk estimates are not of concern to HED.
Page 13 of 29

Table 4.1.1. Short- and Intermediate-term Exposure & Risk to Occupational Handlers For Iprodione Proposed New Use Sites.

Crop or Target Unit Exposure1

(mg ai/lb handled)

Applic. Rate2

(lb ai/A)

Units Treated3

(A/day)

Avg. Daily Dose4

(mg ai/kg /day) MOE4 Combined MOEs4

Mixer/Loader –Liquids –Chemigation Applications

Fruiting vegetables/curcurbits

Dermal

Baseline: 0.220

PPE-G: 0.0376 2 350

Dermal

Baseline: 0.39

PPE-G: 0.067

Dermal

Baseline: 450

PPE-G: 2,600

Baseline dermal + inhalation:

440

PPE-G dermal + Baseline 

inhalation: 2,600 Inhal.

Baseline: 0.000219

Inhal.

Baseline: 0.00077

Inhal.

Baseline: 23,000

Mixer/Loader –Liquids –Groundboom Applications

Fruiting vegetables/curcurbits

Dermal

Baseline: 0.220

2 80

Dermal

Baseline: 0.09

Dermal

Baseline: 2,000 Baseline dermal + inhalation:

1900

PPE-G dermal + Baseline 

inhalation: 11,000

Inhal.

Baseline: 0.000219

Inhal:

Baseline: 0.00018

Inhal.

Baseline: 98,000

Applying Sprays via Groundboom Equipment

Fruiting vegetables/curcurbits

Dermal

Baseline: 0.0786

2 80

Dermal

Baseline: 0.032

Dermal

Baseline: 9,000

Baseline dermal + inhalation:

1,900

Inhal.

Baseline: 0.00034

Inhal.

Baseline: 0.00027

Inhal.

Baseline: 14,000

Inhal.

Baseline: 0.00035

Inhal.

Baseline: 0.0012

Inhal.

Baseline: 5,500

1. See Section 2.1 for additional information 

2. See Section 1.2 for additional information

3. See Section 2.2.1 for additional information

4. See Section 2.2.2 for additional information
Page 14 of 29

2.3 Occupational Handler Cancer Risk Estimates

2.3.1 Occupational Handler Exposure and Cancer Risk Assumptions

The assumptions and factors used in the risk calculations include:

The application rate is 2 lbs ai per acre [proposed curcurbit/vegetable use]. 

The area treated per day is 350 acres for chemigation application and 80 acres for 

groundboom application. These values were derived from ExpoSAC policy 3.1.

To calculate cancer risk estimates, it is assumed that private growers would be exposed 

10 days per year and commercial applicators would be exposed 30 days per year. It is 

assumed that handlers would be exposed for 35 years out of a 70 year lifespan.

The body weight for cancer risk calculations is 80 kg (average bodyweight for U.S. 

adults)

A 5% dermal absorption factor is used for the handler cancer assessment

2.3.2 Occupational Handler Cancer Risk Calculations

EPA conducted an assessment of the carcinogenic risk estimates associated with iprodione 

following exposures to occupational handlers. 

The occupational handler exposure and cancer risk calculations are presented in this section. 

Cancer risk estimates were calculated using a linear low-dose extrapolation approach in which a 

Lifetime Average Daily Dose (LADD) is first calculated and then compared with a Q1* that has 

been calculated for iprodione based on dose response data in the appropriate toxicology study 

(0.044 (mg/kg/day)-1). Absorbed average daily dose (ADD) levels were used as the basis for 

calculating the LADD values. Dermal and inhalation ADD values were first added together to 

obtain combined ADD values. LADD values were then calculated and compared to the Q1* to 

obtain cancer risk estimates.

Lifetime Average Daily Dose: After the development of the ADD values, the next step required 

to calculate the carcinogenic risk is to amortize these values over the working lifetime of 

occupational handlers based on use patterns, which results in the LADD for that use. LADD 

values were calculated using the following equation:

LADD = ADD x Treatment Frequency x Working Duration

365 days/year Lifetime 

Where:

Lifetime Average Daily Dose = the amount as absorbed dose received from exposure to a pesticide in a given 

scenario over a lifetime (mg pesticide active ingredient/kg body weight/day, also referred to as LADD),

Average Daily Dose = the amount as absorbed dose received from exposure to a pesticide in a given scenario on a 

daily basis (mg pesticide active ingredient/kg body weight/day, also referred to as ADD),

Treatment Frequency = the annual frequency of an application by an individual (days/year),

Working Duration = the amount of a lifetime that an individual spends engaged in a career involving pesticide 

exposure (35 years), and
Page 15 of 29

Lifetime = the average life expectancy of an individual (78 years).

Cancer Risk Estimates: Cancer risk calculations were completed by comparing the LADD 

values calculated above to the Q1* values for iprodione (Q1* = 0.044 (mg/kg/day)-1). The 

Agency considered more typical users in these calculations (i.e., private growers at 10 events per 

year) as well as more frequent users that might represent commercial applicators (i.e., 30 events 

per year). Cancer risk values were calculated using the following equation:

Total Risk = (Dermal LADD + Inhalation LADD) x Q1*

Where:

Risk = Probability of excess cancer cases over a lifetime (unitless),

Dermal Lifetime Average Daily Dose = the amount as absorbed dose received from dermal exposure to a pesticide in 

a given scenario over a lifetime (mg pesticide active ingredient/kg body weight/day, also referred to as LADD),

Inhalation Lifetime Average Daily Dose = the amount as absorbed dose received from inhalation exposure to a 

pesticide in a given scenario over a lifetime (mg pesticide active ingredient/kg body weight/day, also referred to as 

LADD), and

Q1* = Quantitative dose response factor used for linear, low-dose response cancer risk calculations (mg/kg/day)-1.

For this assessment, cancer risk estimates were calculated at the proposed label PPE for 

occupational handlers and then with increasing tiers of personal protective equipment for review 

by the risk manager. 

2.3.3 Occupational Handler Cancer Risk Estimates

All of the cancer risk calculations for occupational iprodione handlers completed in this 

assessment are included in Tables 2.3.3a and 2.3.3b. The specifics of each table and a brief 

summary of results are provided below.

- Table 2.3.3: Iprodione Occupational Handler Cancer Risk Estimates for Private Growers: 

Presents cancer risk estimates for combined dermal and inhalation for private growers 

(i.e., 10 applications per year) with each possible combination of dermal and respiratory 

protection considered in this assessment.

- Table 2.3.4: Iprodione Occupational Handler Cancer Risk Estimates for Commercial 

Applicators: Presents cancer risk estimates for combined dermal and inhalation for 

commercial applicators (i.e., 30 applications per year) with each possible combination of 

dermal and respiratory protection considered in this assessment. 

The LADD values were applied to the Q1* value to calculate the cancer risk estimates as 

described above. Cancer risk estimates were calculated for different exposure scenarios at 

different levels of personal protective equipment. For the private grower scenario, cancer risk 

estimates range from 1.0 x10-6to 1.0x10-6 at the proposed label PPE. For the commercial grower 

scenario, cancer risk estimates range from 6.8x10-6to 3.0 x10-5 at the proposed label PPE. 

The proposed label requires that mixer/loaders wear long-sleeve shirt and long pants, chemical 

resistant gloves, chemical resistant footwear plus socks, and a chemical resistant apron (single 

layer plus gloves and no respirator). The label requires applicators using mechanical ground 
Page 16 of 29

equipment wear long-sleeve shirt and long pants and shoes plus socks (single layer, no gloves 

and no respiratory protection).

Table 2.3.3. Iprodione Occupational Handler Cancer Risk Estimates - Private Grower

Exposure 

Scenario

Amount of 

Ai Applied 

per Day

PPE

Total Average 

Daily DoseA

(mg/kg/day)

Lifetime 

Average Daily 

DoseB

(mg/kg/day)

Cancer RiskC

Q1*=0.044 mg/kg/day-1

Mixer/ Loader Scenarios

Mix/Load Liquid 

for Chemigation

2 lb ai/acre X

350 acres/day 

= 700 lb 

ai/day

Dermal – Double 

Layer Gloves

Inhalation –

Baseline

0.017 0.00023

1.0x 10-5

(required label PPE)

Dermal – Double 

Layer Gloves

Inhalation – PF5 

Respirator

0.01455 0.0002 9.0 x 10-6

Dermal – Double 

Layer Gloves

Inhalation – PF10

Respirator

0.019 0.00026 1.1x 10-5

Mix/Load Liquid 

for Groundboom 

Application

2 lb ai/acre X

80 acres/day 

= 160 lb 

ai/day

Dermal – Double 

Layer Gloves

Inhalation –

Baseline

0.0033 0.000052 1.0x 10-6

(required label PPE)

Dermal – Double

Layer Gloves

Inhalation – PF5 

Respirator

0.0034 0.000047 7.6 x 10-7

Dermal – Double 

Layer Gloves

Inhalation – PF10

Respirator

0.0034 0.000059 7.1 x 10-7

Applicator Scenarios

Apply Spray by 

Open Cab 

Groundboom

2 lb ai/acre X

80 acres/day 

= 160 lb 

ai/day

Dermal –

Baseline

Inhalation –

Baseline

0.0098 1.3E-04 4.6 x 10-6

(required label PPE)

A. Dermal dose (mg/kg/day) = [unit exposure (mg/lb ai) * lb ai handled per day * Dermal absorption factor (0.05))] / BW (80 kg)

Inhalation dose (mg/kg/day) = [unit exposure (mg/lb ai) * lb ai handled per day)] / BW (80 kg)

Total average daily dose (mg/kg/day) = dermal dose (mg/kg/day) + inhalation dose (mg/kg/day)

B. Lifetime Average daily dose (mg/kg/day) = Total Average Daily Dose * (10 days for private grower/ 365 days) * (35 years/80 years)

C. Cancer Risk = Lifetime Average Daily Dose (mg/kg/day) * Q1*(0.044 mg/kg/day-1)
Page 17 of 29

Table 2.3.4. Iprodione Occupational Handler Cancer Risk Estimates - Commercial 

Grower

Exposure Scenario Amount of Ai 

Applied per Day PPE

Total 

Average 

Daily DoseA

(mg/kg/day)

Lifetime 

Average Daily 

DoseB

(mg/kg/day)

Cancer 

RiskC

Q1*=0.044 

mg/kg/day-1

Mixer/ Loader Scenarios

Mix/Load Liquid for 

Chemigation/ Aerial 

Application

2 lb ai/acre X

350 acres/day = 700 

lb ai/day

Dermal – Double 

Layer Gloves

Inhalation –

Baseline

0.017 0.00069

3.0 x 10-5

(required label 

PPE)

Dermal – Double 

Layer Gloves

Inhalation – PF5 

Respirator

0.015 0.00061 2.7 x 10-5

Dermal – Double 

Layer Gloves

Inhalation –

PF10 Respirator

0.019 0.00061 2.4 x 10-5

Mix/Load Liquid for 

Groundboom Application

2 lb ai/acre X

80 acres/day = 160 lb 

ai/day

Dermal – Double 

Layer Gloves

Inhalation –

Baseline

0.0038 0.00016

6.8 x 10-6

(required label 

PPE)

Dermal – Double

Layer Gloves

Inhalation – PF5 

Respirator

0.0034 0.00014 6.2 x 10-6

Dermal – Double 

Layer Gloves

Inhalation –

PF10 Respirator

0.0034 0.00014 6.2 x 10-6

Applicator Scenarios

Apply Spray by Open Cab 

Groundboom

2 lb ai/acre X

80 acres/day = 160 lb 

ai/day

Dermal –

Baseline

Inhalation –

Baseline

0.0098 4.0E-04

1.4 x 10-5

(required label 

PPE)

A. Dermal dose (mg/kg/day) = [unit exposure (mg/lb ai) * lb ai handled per day * Dermal absorption factor (0.05))] / BW 

(80 kg)

Inhalation dose (mg/kg/day) = [unit exposure (mg/lb ai) * lb ai handled per day)] / BW (80 kg)

Total average daily dose (mg/kg/day) = dermal dose (mg/kg/day) + inhalation dose (mg/kg/day)

B. Lifetime Average daily dose (mg/kg/day) = Total Average Daily Dose * (30 days for private grower/ 365 days) * (35 

years/78 years)

C. Cancer Risk = Lifetime Average Daily Dose (mg/kg/day) * Q1*(0.044 mg/kg/day-1)
Page 18 of 29

3.0 Occupational Postapplication Exposures and Risk Estimates

HED uses the term post-application to describe exposures that occur when individuals are 

present in an environment that has been previously treated with a pesticide (also referred to as reentry exposure). Such exposures may occur when workers enter previously treated areas to 

perform job functions, including activities related to crop production, such as scouting for pests 

or harvesting. Post-application exposure levels vary over time and depend on such things as the 

type of activity, the nature of the crop or target that was treated, the type of pesticide application, 

and the chemical’s degradation properties. In addition, the timing of pesticide applications, 

relative to harvest activities, can greatly reduce the potential for postapplication exposure.

Post-application exposures to the proposed iprodione uses on curcurbits and fruiting vegetables 

uses have not been assessed in this document as the exposure potential is low. The proposed 

label is for chemigation/soil incorporation applications that are watered in to the top 3-5 inches 

of soil. In cases like iprodione where the proposed uses do not follow the standard “foliar-based” 

transfer coefficient methodology, exposure assessors reference ExpoSAC policy 3.1 on guidance 

on crop-activity combinations utilizing an alternate transfer coefficient method.

Due to the method and timing of applications and typical agricultural practices for these crops, 

HED has determined that a specific post-application exposure assessment is not necessary for 

these scenarios. This determination is based on the following: (1) routine hand labor activities 

that involve significant contact with the treated soil/planting medium are not required, or are not 

required for several weeks or months after the application, and (2) reentry activities that may be 

necessary are likely to result in relatively low levels of dermal exposure because contact with the 

treated medium (soil) is minimal or infrequent.

3.1 Occupational Postapplication Exposure and Non-Cancer Risk Estimates

Occupational Postapplication Dermal Exposure

Based on a review of the non-cancer hazard database, HED believes that the potential for dermal 

postapplication worker exposure is low, provided at least a 12-hour restricted entry interval 

(REI) and other proposed restrictions based on worker reentry are observed. 

As noted above, the proposed use pattern is for soil directed/soil-incorporated applications of 

iprodione and thus no foliage will be contacted. Additionally, reentry activities that may be 

necessary are likely to result in negligible dermal exposure because contact with the treated 

medium is infrequent.

Occupational Postapplication Inhalation Exposure

Based on the Agency's current practices, a quantitative postapplication inhalation exposure 

assessment was not performed for iprodione at this time primarily because it has a low vapor 
Page 19 of 29

pressure (3.8 x 10-9 mm Hg

1

). However, volatilization of pesticides may be a potential source of 

post-application inhalation exposure to individuals nearby to pesticide applications. The Agency 

sought expert advice and input on issues related to volatilization of pesticides from its Federal 

Insecticide, Fungicide, and Rodenticide Act Scientific Advisory Panel (SAP) in December 2009. 

The Agency received the SAP’s final report on March 2, 2010 

(http://www.epa.gov/scipoly/SAP/meetings/2009/120109meeting.html). The Agency is in the 

process of evaluating the SAP report and may, as appropriate, develop policies and procedures to 

identify the need for and, subsequently, the way to incorporate postapplication inhalation 

exposure into the Agency's risk assessments. If new policies or procedures are put into place, the 

Agency may revisit the need for a quantitative postapplication inhalation exposure assessment 

for iprodione.

Although a quantitative postapplication inhalation exposure assessment was not performed, an 

inhalation exposure assessment was performed for occupational/commercial handlers. Handler 

exposure resulting from application of pesticides outdoors is likely to result in higher exposure 

than postapplication exposure. Therefore, it is expected that these handler inhalation exposure 

estimates would be protective of most occupational postapplication inhalation exposure 

scenarios.

3.2 Occupational Postapplication Cancer Risk Estimates

3.2.1 Occupational Postapplication Exposure and Cancer Risk Assumptions

HED typically assesses dermal postapplication exposure potential for field workers, for both 

non-cancer and cancer assessments (when a Q1* has been determined). HED has identified a Q1* 

for the parent compound and one Q1* from a iprodione degradate. However, because of review 

of the proposed label and proposed use pattern, HED has determined that a quantitative postapplication exposure assessment is not necessary for these scenarios. The determination is based 

on the exposure potential (similar to the non-cancer exposure potential characterization identified 

above in section 3.0) for the parent compound. 

While there is an additional Q1* value for a degradate of iprodione (3,5-DCA2); no quantitative 

postapplication cancer assessment has been completed for the degradate. The proposed label for 

fruiting vegetables and curcurbits directs applicators to pre-emergent soil incorporation or postemergent soil directed sprays. Therefore, there is negligible occupational postapplication dermal 

potential for the parent compound, and no post-application dermal exposure potential for the 3,5-

DCA degradate.

 

1

http://www.oehha.org/multimedia/biomon/pdf/0709iprodione.pdf

2

3, 5-DCA is not a registered pesticide; therefore, there are no FIFRA toxicology data for this compound. In the past, HED has used the Q1 * for 

p-chloroaniline (PCA) to assess the carcinogenic risk for other structurally related chloroanilines. The HED policy on chloroanilines specifies that 

chloroaniline metabolites should be considered to be toxicologically equivalent to PCA unless there is sufficient evidence that the metabolite is 

not carcinogenic. A Q1 * of 6.38 X 10-2(mg/kg/day)-1in human equivalents has been calculated for p-chloroaniline. This Q1* is based on the 

spleen sarcoma rate in male rats from an NTP bioasssay, linearized low dose multistage model, and the 3/4s interspecies body scaling factor. 
Page 20 of 29

4.0 Residential Exposure

 

According to the 1998 reregistration eligibility decision (RED) for iprodione, “Based on cancer 

risk concerns, the Agency has determined that iprodione residential uses on turf, ornamentals and 

vegetable/small fruit gardens are ineligible for reregistration. The registrant [at the time of the 

RED], Rhone-Poulenc, has requested to voluntary cancelation of all residential uses of 

iprodione.” Therefore, residential turf uses of iprodione are no longer registered by the Agency. 

However, there are iprodione-based products that can be professionally applied to golf courses, 

where there is potential for non-occupational postapplication exposure to golfers. 

This “golfer” scenario is assessed in this document to update the residential exposure assessment 

and to be used in the updated aggregate exposure assessment. While the agricultural uses of 

iprodione for curcurbits and fruiting vegetables are as a nematicide, HED calculated risk 

estimates for exposure to treated golf course turf to include in the aggregate risk assessment. 

4.1 Residential Handler Exposure

There are no registered residential products that can be applied by residential handlers; therefore, 

residential handler exposure has not been quantitatively assessed.

4.2 Use of TTR Data for Iprodione Post-application Exposure Assessments

This assessment contains potentially compensable turf transferable residue data generated by 

Rhône-Poulenc. The transferable turf residue (TTR) data are available and scientifically sound for 

risk assessment (MRID 44968001; reviewed by HED in D389183). The data set measured TTR 

in 3 locations; Georgia, New York, and California. As data are available, HED evaluated cancer 

risk estimates based on the potential exposure the highest 14 day average TTR value; from the 

California-based measurements. 

There are TTR data available for iprodione (MRID 44968001) and a summary is included in 

Appendix A. Six applications of 5.45 lb iprodione/A in flowable concentrate formulation were 

applied by groundboom in three test sites, GA, CA, and NY. For the residential exposure 

assessment, the predicted TTR values from the California site were used for 14- and 28-day 

averaging to provide a health protective assessment of potential exposure to iprodione parent 

residues. Table 4.3.1 details the TTR values used for the residential exposure assessment.

Calculations of non-cancer postapplication exposures are typically completed using maximum 

application rates identified in the label and “day 0” residue values. In this case, the risk estimates 

are also shown for the highest TTR residue value as a screening level assessment. The maximum 

application rate for products applied to golf courses is 5.5 lb ai/A; therefore the available TTR 

data did not need to be adjusted based on the application rate. Calculations of cancer postapplication exposures are completed using average application rates (2.5 lbs ai/A) identified on 

product labels to reflect lifetime exposure potential. The available TTR data was adjusted to 

reflect that application rate.
Page 21 of 29

Table 4.3.1: Use of TTR data Derived from MRID 44968001

Postapplication 

Exposure Assessment 

Type

TTR value 

used (in 

ug/cm2)

Application 

Rate

Averaging 

time

Site 

Location

Non-Cancer 

Assessment 0.49 Maximum

(5.5 lb ai/A) 14 day California

Cancer Assessment

0.22 Average

(2.5 lb ai/A) 14 day California

0.15 average 28 day California

(2.5 lb ai/A)

Upper bound Cancer 

Assessment1

Greens -1.98

Fairways - 0.49

Maximum

(20/5.5 lb ai/A)2 14 day California

Greens -1.98

Fairways - 0.49

Maximum

(20/5.5 lb ai/A)2

28 day California

1) The upper bound cancer risk assessment reflects a weighted average of residue exposure from time 

spent on fairways vs. greens & maximum application rates

2) Weighted average application rate

4.3 Residential Postapplication Exposure and Non-cancer Risk Estimates

Residential Post-application Dermal Exposure

This action covers the new uses of iprodione on fruiting vegetables and curcurbits. However, this 

document includes qualitative and quantitative exposure assessments for the residential 

postapplication “golfer” scenarios because a revised aggregate assessment is needed to complete 

this iprodione action.

Iprodione residential post-application scenarios include individuals playing golf on treated turf. 

As a result, HED’s Standard Operating Procedures (SOP’s) for Residential Exposure 

Assessments, (2012), as well as chemical-specific residue data from a turf transferable residue 

(TTR) study (MRID 44968001) are used to assess residential golfer exposure. The 2012 

residential SOP’s outline quanitatively assessing exposure to the following lifestages: 1) adults, 

2) 11 to < 16 year olds, and 3) 6 to < 11 year olds. 

4.3.1 Non-Cancer Dermal Post-application Exposure

This scenario assumes that pesticide residues are transferred to the skin of individuals that enter 

treated areas for recreation or other activities such as golfing. Below are some assumptions 

about the dermal exposure potential.

Assumptions:

Residential post-application exposure must be assessed on the same day the pesticide is 
Page 22 of 29

applied since it is assumed that golfers could be exposed to turf grass immediately after 

application. Therefore, exposures are based on “day 0” residues.

TTR value is assumed to be 0.682 ug/cm2based on predicted day 0 residue value 

calculated by a first-order dissipation kinetics and decay model from chemical-specific 

data. A summary of the TTR study is presented in section 4.2 of this document. The full 

study review is available (D389183). An upper bound TTR residue value was used as a 

screening level assessment.

Transfer coefficients (TCs) were used to assess dermal exposure resulting from golfing. 

An average body weight of 69 kg was used to assess dermal exposure for adults. Body 

weights of 57 and 32 were used to assess dermal exposure for 11 to < 16 yrs and 6 to < 

11 yrs old, respectively. Those bodyweights reflect average bodyweights for those age 

groups.

Duration of exposure on golf course lawns, greens and tees is assumed to be 4 hours.

Equations:

Dermal Dose (mg/kg/day) = [TTR (μg/cm2) x 0.001 (mg/μg) x TC (cm2/hr) x ET (hr/day)]/BW (kg)

Where:

Dose = Dermal exposure on day of application attributable for activity in a previously 

treated area (mg/kg/day);

TTR = Turf Transferable Residue (μg/cm2);

TC = Transfer Coefficient (cm2/hr);

ET = Exposure Time (hours); and,

BW = Body Weight (kg).

Dermal MOE = LOAEL (mg/kg/day)/Dermal Dose (mg/kg/day)

Post-application Dermal Exposure and Risk Estimate

Short-term dermal post-application exposure and risk estimates for golfers resulted in MOEs 

greater than the LOC and therefore are not of concern to HED. A summary of the residential 

short-term dermal exposures is shown below in Table 4.2.1. Risk estimates are presented with 

the highest predicted residue values and the predicted “day 0” residue values; neither present risk 

estimates of concern based on the level of concern of 1,000.

Table 4.2.1. Post-application Short-term Dermal Exposure and Risk Estimates for Iprodione.

Scenario Application 

Rate

(lb ai/A)

TTR 1

(μg/cm2)

CF TC

2

(cm2/hr)

ET 

(hrs)

BW 

(kg)

Dose 3

(mg/kg/day)

Dermal

MOE 4

Golfer

Adult 5.5 0.682 0.001 5,300 4 69 0.010 4,800

11 to < 16 yrs old 5.5 0.682 0.001 4,400 4 57 0.011 4,700

6 to < 11 yrs old 5.5 0.682 0.001 2,900 4 32 0.012 4,000

Adult 5.5 0.85 0.001 5,300 4 69 0.013 3,800

11 to < 16 yrs old 5.5 0.85 0.001 4,400 4 57 0.013 3,800
Page 23 of 29

Table 4.2.1. Post-application Short-term Dermal Exposure and Risk Estimates for Iprodione.

Scenario Application 

Rate

(lb ai/A)

TTR 1

(μg/cm2)

CF TC

2

(cm2/hr)

ET 

(hrs)

BW 

(kg)

Dose 3

(mg/kg/day)

Dermal

MOE 4

6 to < 11 yrs old 5.5 0.85 0.001 2,900 4 32 0.015 3,200

1. Turf Transferable Residues (TTR) = 0.682 ug/cm2is based on predicted day 0 residue value calculated from chemicalspecific data (MRID No. 44968001). 0.85 ug/cm2 is the highest predicted residue value run as a screening level assessment.

2. Transfer Coefficients are derived from HED’s “Science Advisory Council for Exposure (ExpoSAC) Policy 3- Revised 

March 2012”

3. Dermal Dose (mg/kg/day) = [TTR (μg/cm2) x 0.001 (mg/μg) x TC (cm2/hr) x ET (hr/day)]/ BW (kg).

4. Dermal MOE = LOAEL (50 mg/kg/day)/Dermal Dose (mg/kg/day).
Page 24 of 29

Spray Drift

Spray drift is a potential source of exposure for residents living in close proximity to spraying 

operations. This is particularly the case with aerial application, but, to a lesser extent, could also 

be a potential source of exposure from the ground application method employed for iprodione. 

The Agency has been working with the Spray Drift Task Force (a membership of US pesticide 

registrants), EPA Regional Offices, State Lead Agencies for pesticide regulation, and other 

parties to develop the best spray drift management practices. The Agency is now requiring 

interim mitigation measures for aerial applications that must be placed on product 

labels/labeling. The Agency has completed its evaluation of the new database submitted by the 

Spray Drift Task Force, and is developing a policy on how to appropriately apply the data and 

the AgDRIFT computer model to its risk assessments for pesticides applied by air, orchard 

airblast, and ground hydraulic methods. After the policy is in place, the Agency may impose 

further refinements in spray drift management practices to reduce off-target drift with specific 

products with significant risk estimates associated with drift.

Residential Postapplication/Bystander Inhalation Exposure

Based on the Agency's current practices, a quantitative postapplication inhalation exposure 

assessment was not performed for iprodione at this time. However, volatilization of pesticides 

may be a potential source of postapplication inhalation exposure to individuals nearby to 

pesticide applications. The Agency sought expert advice and input on issues related to 

volatilization of pesticides from its Federal Insecticide, Fungicide, and Rodenticide Act 

Scientific Advisory Panel (SAP) in December 2009. The Agency received the SAP’s final report 

on March 2, 2010 (http://www.epa.gov/scipoly/SAP/meetings/2009/120109meeting.html). The 

Agency is in the process of evaluating the SAP report and may, as appropriate, developing 

policies and procedures, to identifying the need for and, subsequently, the way to incorporate 

postapplication inhalation exposure into the Agency's risk assessments. If new policies or 

procedures are put into place, the Agency may revisit the need for a quantitative postapplication 

inhalation exposure assessment for iprodione.

4.4 Residential Postapplication Exposure and Cancer Risk Estimates

There are currently registered products that can be professionally applied to golf courses, where 

there is potential for postapplication residential exposure to golfers. This scenario is assessed in 

this document to update the residential exposure assessment and to be used in the updated 

aggregate exposure assessment.

HED calculates cancer risk estimates for adults exposed to pesticide products during recreational 

activities. In this case, pesticide products containing iprodione can be applied commercially to 

golf courses, and recreational golfers can be exposed to those residues. Adult cancer risk

estimates were calculated from golfer exposure to previously treated golf course turf. HED 

expects dermal exposure is the primary exposure route for adults exposed through recreational 

golf. 
Page 25 of 29

The postapplication cancer assessment reflects exposure to parent iprodione. No quantitative 

postapplication cancer assessment has been completed for the iprodione degradate 3,5-DCA. The 

Q1*for 3,5-DCA is not relevant to the residential postapplication exposure assessment (i.e., 

golfer scenario) since iprodione is metabolized to 3,5-DCA in drinking water.

Below are the algorithms and assumptions used to assess residential post-application exposure 

and cancer risk estimates. Exposure scenarios assessed include:

Adult dermal exposure to treated golf course (adults/young adults)

Assumptions for Post-application Exposure Scenarios

General assumptions regarding the residential postapplication scenarios assessed are as follows:

The body weight for cancer risk assessment is 80 kg 

HED has developed standard transfer coefficient (TC) values for residential postapplication scenarios to ensure consistency in exposure assessments. These standard 

values were used to calculate post-application exposures. The TC for golfing exposure is 

3400 cm

2

/hr, when chemical-specific TTR data are used from a TTR study which used 

the modified California Roller technique. 

There are TTR data available for iprodione (MRID 44968001). The data were used as 

outlined above in Table 4.3.1.

Duration of exposure on golf course lawns, greens and tees is assumed to be 4 hours. For 

the upper bound cancer assessment, it’s assumed that golfers are exposed on greens for 1 

hour and on fairways for 3 hours.

It is assumed that 20 days per year are spent golfing based on golfing survey from United 

States Golf Association (USGA). 

Golfers are assumed to be in contact with golf course turf for approximately 50 years 

over a 78 year life time in determining cancer risk.

Similar to occupational handlers, cancer risk estimates were calculated using a linear low-dose 

extrapolation approach in which a Lifetime Average Daily Dose (LADD) is first calculated and 

then compared with a Q1* that has been calculated for iprodione based on dose response data in 

the appropriate toxicology study (Q1* = 0.0087 (mg/kg/day)-1). Absorbed average daily dose 

(ADD) levels were used as the basis for calculating the LADD values. After the development of 

the ADD values, the next step required to calculate the carcinogenic risk is to amortize these 

values over the working lifetime of the occupational workers with postapplication exposure 

based on use pattern, which results in the LADD for that use. The Agency assumed 

postapplication exposure to treated golf courses could occur 20 days per year based on a golfing 

survey from USGA. Finally, 50 years of golfing activity in a 78 year lifespan were used to 

complete the calculations. LADD values were calculated using the following equation:

LADD = ADD x Exposure Frequency x Activity Duration

365 days/year Lifetime 

Where:
Page 26 of 29

LADD (Lifetime Average Daily Dose) = the amount as absorbed dose received from exposure to a pesticide in a 

given scenario over a lifetime (mg pesticide active ingredient/kg body weight/day, also referred to as LADD),

ADD (Average Daily Dose) = the amount as absorbed dose received from exposure to a pesticide in a given scenario 

on a daily basis (mg pesticide active ingredient/kg body weight/day, also referred to as ADD),

Exposure Frequency = the annual frequency of exposure by an individual (days/year),

Activity Duration = the amount of a lifetime that an individual spends engaged in an activity (i.e. golfing) involving 

pesticide exposure (50 years), and

Lifetime = the average life expectancy of an individual (78 years).

Cancer Risk Estimates: Finally, cancer risk calculations were completed by comparing the 

LADD values calculated above to the Q1* for iprodione (Q1* = 0.044 (mg/kg/day)-1). Cancer 

risk values were calculated using the following equation:

Cancer Risk Estimate = Dermal LADD (mg/kg/day) * Q1* (mg/kg/day)-1

Where:

Risk = Probability of excess cancer cases over a lifetime (unitless),

Dermal Lifetime Average Daily Dose = The amount as absorbed dose received from dermal exposure to a pesticide 

in a given scenario over a lifetime (mg pesticide active ingredient/kg body weight/day, also referred to as LADD), 

and

Q1* = Quantitative dose response factor used for linear, low dose response cancer risk calculations (mg/kg/day)

-1

.

Table 4.4B: Residential Postapplication Cancer Dermal Exposure and Risk with Q1* value of 0.044:

Scenario TTR A

(ug/cm2)

CF 

(mg/μg)

Tc

(cm2/hr)

ET 

(hrs)

BW 

(kg)

Dose B 

(mg/kg/day)

LADD C

mg/kg/day

Cancer 

Risk D

Average Application Rate

Adult Golfer

14-day TTR avging

0.22 0.001 5300 4 80 0.0029 0.000102 4.5 x10-6

 

Adult Golfer

28-day TTR avging

0.15 0.001 5300 4 80 0.0020 0.000072 3.2 x10-6

 

Upper Bound Application Rate

Adult Golfer

14-day TTR avging

Greens -

1.984

Fairways -

0.49

0.001 5300 4 80 0.0049 0.000403 1.8 x10-5

 

A. Turf Transferable Residues (TTR) from study MRID 44968001.

B. Dermal Dose (mg/kg/day) = TTR (μg/cm2) x 0.001 (mg/μg) x TC (cm2/hr) x ET (hr/day) x 5% DA

BW (80 kg) 

C. Life Average Daily Dose (LADD) = Daily Dose (mg/kg/day) x 20 days x 50 years 

 365 days 78 lifetime years

D. Cancer Risk = Q1* (4.4 x 10-2 mg/kg/day-1) x LADD (mg/kg/day)

The refined residential post-application cancer assessment assumes that a golfer is exposed to the 

same residue pattern 20 golfing days per year over 50 years of assumed golf play activity. The 

risk estimates range from 3.2x10-6to 1.8x10-5. This assessment involves significant refinement

over a screening level assessment. Refinements include the use of TTR data, average application 

rates to reflect an individuals’ lifetime exposure, and residue averaging based on likely product 

application parameters.
Page 27 of 29

The product in the TTR study (Chipco® 26GT) is one of the most widely used products for turf, 

and is a good representative end use product for the TTR data. The 14- and 28-day average 

transferable turf residues were used to calculate the cancer risk estimates. The product label 

suggests application intervals of 14 to 28 days; cancer risk estimates are presented as a range 

based on: 1) an upper bound cancer risk estimate based on maximum label application rates and 

2) 14-day and 28-day TTR averages of an average iprodione application rate. 

Sometimes meteorological information like rainfall events, or turf treatment regimes can be used 

to characterize an exposure assessment using a TTR data set. The study report doesn't identify 

any out of the ordinary issues that would limit the use of this study for use in human health risk 

assessment. Both the timing of rainfall events and the timing of turf mowing are unclear from the 

iprodione TTR study report. The study report indicated some precipitation during the TTR study. 

The treated turf received care similar to standard industrial turf through typical irrigation and 

mowing procedures.

5.0 Label Recommendation

The product label includes several established uses and proposed new uses on curcurbits. The 

proposed label (86153-3) includes general product directions for both foliar and pre-plant/soilincorporated directions for various crops. The label section for the proposed new curcurbit uses 

instructs users on the pre-plant and soil-incorporated applications. There are no instructions for 

foliar applications for curcurbits; therefore, this assessment did not include a quantitative

occupational postapplication assessment for curcurbits. Based on the proposed use pattern, the

proposed product label should be additionally modified to clarify that foliar application is 

prohibited for the proposed new uses on curcurbits.
Page 28 of 29

APPENDIX A: IPRODIONE DFR STUDY SUMMARYAppendix A: Summaries of 

Dislodgeable Foliar Residue Studies and Proposed Use in Assessment

DFR Studies Available:

Iprodione: Review of Iprodione: Determination of Transferable Turf Residues on Turf Treated 

with CHIPCO® 26GT, TAF 0-5, MRID 44968001. 

(HED Review: Review of “Determination of Transferable Turf Residue Dissipation from Turf Treated 

with Iprodione” , 04/27/2011, D389183)

The chemical-specific TTR study included three field trial sites in Georgia, California, and New 

York. The study was conducted on turf to evaluate the decline of iprodione equivalent residue

(i.e., parent + metabolite) after six applications of a flowable concentrate iprodione product at a 

maximum application rate of 5.45 lbs ai/A/application. The re-treatment interval was 

approximately 14 days. The Modified California Roller technique was used to evaluate the 

amount of transferable residues from turf grass. A summary of the California site TTR values 

used in the residential exposure assessment is provided in Table A. 

There are TTR data available for iprodione (MRID 44968001). Six applications of 5.45 lb 

iprodione/A in flowable concentrate formulation were applied by groundboom in three test sites, 

GA, CA, and NY. The highest TTR value from the Georgia site was 5 days after the sixth 

application; the TTR was 0.63 ug/cm2. The 14 day average TTR value after 6 applications was 

0.3506 ug/cm2. The highest TTR value from the California site was 3 days after the sixth 

application; the TTR was 0.848 ug/cm2. The 14 day average was 0.4924 ug/cm2. The highest 

TTR value from the New York site was 8-12 hours after the sixth application; the TTR was 0.608 

ug/cm2. The 14 day average was 0.4457 ug/cm2.

Peak residue formation occurred at 5DAT6 in Georgia, 3DAT6 in California, and 8-12 hrs DAT6 

in New York. This phenomenon could possibly be explained by the delayed formation of the 

iprodione metabolite. The dissipation was only followed for 14 days, and the residues never 

reached levels less than the LOQ during the timeframe of the study. Immediately following the 

last application of the test product, the percentage of the original application rate of iprodione 

transferable to cotton sheeting material was 0.81% for the Georgia site, 1.12% for the California 

site, and 0.83% for the New York site. 

First-order dissipation kinetics were assumed to generate dissipation curves for iprodione. The

individual data points (rather than averages) from postapplication to 14DAT6 at the Georgia and 

California test sites. Due to the extreme variability in TTR for individual days at the New York 

test site, use of individual data points for regression analysis was not appropriate. Average daily 

data points were most appropriate for the New York site. 

The estimated half-life values were 8.1 days (R2=0.777) for Georgia, 9.8 days (R2=0.618) for 

California, and 20.7 days (R

2 = 0.626) for the New York turf. While the Registrant did not correct 

for field recoveries, their calculated half-lives were similar to Agency calculated half-lives.

This study is acceptable to be used for risk assessment purposes.
Page 29 of 29

Table A: Summary of Predicted TTR Levels Used in Residential Exposure Assessment (5.5 lbs ai/A 

unadjusted application rate)

Days after last 

Treatment

CA Site Mean 

Residue (ug/cm2)

0 0.777

1 0.724

2 0.674

3 0.628

4 0.585

5 0.545

6 0.508

7 0.474

8 0.441

9 0.411

10 0.383

11 0.357

12 0.333

13 0.310

14 0.289

15 0.269

16 0.251

17 0.234

18 0.218

19 0.203

20 0.189

21 0.176

22 0.164

23 0.153

24 0.143

25 0.133

26 0.124

27 0.115

28 0.107