FLUOXASTROBIN Human Health Risk Assessment DP No. 0421420 

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

MEMORANDUM 

DATE: July 9, 2014 

OFFICE OF 

CHEMICAL SAFETY AND 

POLLUTION PREVENTION 

SUBJECT: Addendum: Fluoxastrobin. Revised Aggregate Human Health Risk Estimate 

for Children 1 to <2 Years Old in Response to Review of Turf Transferable 

Residue Study (Previously Required Data Deficiency) Submitted by Registrant. 

PC Code: 028869 DP Barcode: D421420, D405370, D404179 

Decision No.: 489469 '/~77'/. f'ttf/IJ Registration Nos.: 66330-64, 66330-65 

Petition No.: 2F8047, 9F7567 Regulatory Action: Section 3 

Case No.: NA Risk Assessment Type: Single Chemical/Aggregate 

TXRNo.: NA CAS No.: 361377-29-9 

MRID No.: 49341901 40 CFR: §180.609 

FROM: Nancy J. Keller, Chemist, Risk Assessor 

Risk Assessment Branch 3 

Health Effects Division (7509P) 

THROUGH: Christine Olinger, Branch Chief /)~ h 

Risk Assessment Branch 3 ~/'/ • 

Health Effects Division (7509P) 

TO: Heather Garvie/Shaja Joyner, RM #20 

Fungicides Branch (FB) 

Registration Division (7505P) 

The Registration Division (RD) requested that the Health Effects Division (HED) provide an 

evaluation of the turf transferable residue (TTR) study submitted by Arysta LifeScience North 

America, LLC (Arysta) to satisfy a data deficiency listed in the most recent risk assessment 

(DP405370, N. Tsaur, 03/27/2013). This addendum incorporates the TTR study results and 

provides updated revisions to the human health risk assessment that result from the changes to 

residential turf exposure (primarily children, 1 to <2 years old). The TTR data evaluation record 

(DER) and the updated aggregate human health risk estimates were conducted by Nancy Keller. 

The results ofthe study indicate a slight increase (- 2X) in the TTR value when compared to the 

default assumption used in the previous risk assessments (DP419228, N. Keller, 06/06/2014). 

Thus, this document highlights the direct changes in risk estimates that result from the new data, 

including the children's postapplication incidental oral risk estimates, and the children's 

aggregate risk estimates. 

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FLUOXASTROBIN Human Health Risk Assessment DP No. D421420 

1.0 Introduction 

Fluoxastrobin is a strobilurin-class fungicide that controls foliar fungal diseases and 

soilborne/seedling fungal diseases. It works by interrupting mitochondrial respiration in plantpathogenic fungi, thus inhibiting spore germination and mycelial growth. 

The two most recent fluoxastrobin risk assessments involved the product Fluoxastrobin 480 SC 

Fungicide (EPA Reg. No. 66330-64), a suspension concentrate (SC) formulation containing 

40.3% active ingredient (ai) by weight (3.98 lb ai per gallon). 

In PP#2F8047, Arysta submitted a label amendment to add melon subgroup 9A and sorghum to 

the master label for Fluoxastrobin 480 SC Fungicide, thus petitioning for the associated 

tolerances (DP405370, N. Tsaur, 03/27/2013). 

Prior to the most recent petition, Arysta submitted a label amendment to remove the homeowner 

use restriction from the turf and ornamentals section of the master label for Fluoxastrobin 480 

SC Fungicide, thus proposing a new residential use (DP404179, N. Tsaur, 11113/2012). 

Based on previous results of the residential turf postapplication risk assessment, a TTR study 

was required for fluoxastrobin, and listed as a data deficiency. The incidental oral hand-tomouth margin of exposure (MOE) for young children (1 to <2 years old) was less than 1,000 

(MOE= 390, LOC = 1 00) based on default values for the fraction of application rate available 

for transfer after a liquid application to turf(N. Tsaur, 0406106, 10/25/2012). 

Arysta has since submitted a TTR study for review. The predicted initial residue values (and 

percent of application rate) at ODAT1 were: 0.124 J..l.g/cm2 (2.2%) at the Pennsylvania site; 0.066 

J..l.g/cm2 (1.2%) at the Georgia site; and 0.034 J..l.g/cm2 (0.61%) at the California site (DP419228, 

N. Keller, 06/06/2014). The results ofthe study indicate a slight increase (~2X) in the TTR 

value when compared to the default assumption used in the previous risk assessments. Thus, this 

document highlights the direct changes in risk estimates that result from the new data. Since the 

TTR data only affect the residential exposure component and dermal hazard is not of concern, 

the TTR data only affect children's incidental oral risk estimates, which thus translates to a 

change in children's aggregate risk estimates. 

Aside from a slight increase in the incidental oral exposure of young children from fluoxastrobin 

use on residential turf, and the associated aggregate changes, all other assumptions and risk 

estimates remain unchanged from the previous risk assessments. All of the following topics of 

interest can be found in detail in the two previous risk assessments: the hazard characterization 

and toxicity endpoints for risk assessment, the rationale to support the Food Quality Protection 

Act (FQPA) safety factor, the proposed use profile, the exposure profile, the dietary exposure 

profile, the drinking water profile, and the occupational exposure profile. 

Residential Exposure and Risk Estimates 

Upon incorporating the new TTR data, all existing registered uses do not result in any residential 

handler or post-application risk estimates of concern. The lowest and most protective incidental 

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FLUOXASTROBIN Human Health Risk Assessment DP No. D421420 

oral post-application MOE for children (1 to <2 years old) is 180 based on hand to mouth 

activities on turf treated with a liquid formulation of fluoxastrobin. 

Aggregate Exposure Risk Estimates 

Upon incorporating the new TTR data, the aggregate MOE for children (1 to <2 years old) is 

greater than 100, which indicates that exposure and risk estimates do not exceed HED's LOC. 

The children's short-term aggregate (dietary + residential) MOE is 110. Acute exposures were 

not considered because an adverse effect attributable to a single dose was not identified. Since 

there are neither intermediate-term nor chronic residential exposure scenarios, the aggregate risk 

estimates are expected to be equivalent to chronic dietary (food and drinking water) risk 

estimate. Fluoxastrobin is classified as "not likely to be carcinogenic to humans;" therefore, an 

aggregate cancer assessment was not conducted. 

2.0 Residential (Non-Occupational) Exposure/Risk Estimates for Children 

Young children (1 to <2 years old) may receive incidental oral post-application exposure to 

fluoxastrobin from treated turf. Although residential dermal exposure is expected following the 

treatment of turf, short-term dermal hazard was not identified for fluoxastrobin. Therefore, a 

quantitative post-application dermal risk assessment was not conducted; Only short-term 

incidental oral exposure and risk estimates have been assessed for the physical activities of 

children 1 to <2 years old on turf, following liquid and granular application of fluoxastrobin at 

maximum registered application rates. Intermediate-term incidental oral exposure is not 

expected for post-application activities to turf because residues are unlikely to persist for longer 

than one month due to turf maintenance (e.g. mowing) and climate (e.g. rain). 

Table 1 presents the most protective post-application incidental oral MOE value calculated for 

liquid applications of fluoxastrobin to turf. The post-application risk estimates is not of concern 

to HED (MOE= 180). 

Table 1. Short-Term Residential Post-Application Exposure and Risk Estimates for Fluoxastrobin on Turf" 

Post-Application Exposure Scenariob 

Dose 

Lifestage mg/kglday 

MOEC 

Child 1 to < 2 years old Hand to Mouth 0.0170 180 .. a Based on regtstered product label for Fluoxastrobm 480 SC Fungtctde (EPA Reg. No. 66330-64); SC Ltqutd 

Formulation; 3.69lb ai/gallon; max single application rate = 0.46 lb ai/A. 

b Hand-to-Mouth Dose = hand residue loading (mg/cm2) x fraction of hand mouthed (0.127) x surface area of 1 

hand (150 cm2) x exposure time (1.5 hrs/day) x #of replenishment intervalslhr ( 4 intlhr) x ( 1-((1 -saliva extraction 

factor (0.5))1'(Number of hand-to-mouth events per hour (13.9 eventslhr) +# of replenishment intervalslhr)) + 

body weight (11 kg). 

TTR = 0.124 j.lg/cm2 (DP419228, N. Keller, 06/06/20 14) 

c MOE= NOAEL +Daily Dose (mg/kg/day). Incidental Oral NOAEL= 3.0 mgfkg/day. Level of concern= 100. 

3.0 Short-Term Aggregate Exposure/Risk Estimates for Children 

HED must consider and aggregate (add) pesticide exposures and risks from three major sources: 

food, drinking water, and residential exposures. In an aggregate assessment, exposures from 

relevant sources are added together and compared to quantitative estimates ofhazard (e.g. a 

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FLUOXASTROBIN Human Health Risk Assessment DP No. D421420 

NOAEL or PAD), or the risks themselves can be aggregated. When aggregating exposures and 

risks from various sources, HED considers both the route and duration of exposure. For 

fluoxastrobin, potential exposures from food, drinking water, and residential scenarios were 

aggregated. 

Short-Term Aggregate Risk 

There is potential short-term exposure to fluoxastrobin via the dietary (which is considered 

background exposure) and residential (which is considered primary) pathways. For children, 

these pathways lead to exposure via the oral (background) and incidental oral (primary) routes. 

The most protective residential exposure risk estimates are included in the aggregate exposure 

assessment. The recommended residential exposure for use in the children 1 <2 years old 

aggregate assessment reflects hand-to-mouth exposures from post-application exposure to liquid 

applications to turf (MOE = 180). Aggregate MOEs are greater than 100, which indicates that 

exposure and risk do not exceed HED's level of concern. The children short-term aggregate 

(dietary + residential) MOE is 110, as shown in Table 2. 

Table 2. Short-Term Aggregate Risk Calculations 

Max Average 

Food and Residential 

Population 

NOAEL Loca Allowable Water Exposurec Exposureb Exposure 

mg!kg!day mglkg!day mg/kg/day mg/kglday 

Children 3.0 100 0.030 0.009516 0.0170 1-2 years old 

a LOC = 100 (based on mter- and mtra- spec1es uncertamty factors totalmg I OOX). 

b Maximum Allowable Exposure (mglkg/day) = NOAEL 7 LOC. 

c Residential Exposure= Incidental Oral Only for children (See Table 1). 

d Total Exposure = Average Food and Water Exposure + Residential Exposure. 

e Aggregate MOE = NOAEL + Total Exposure. NOAEL = 3 mg/kg/day. LOC = 100. 

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Aggregate Total 

Exposured MOE(food, 

water, and 

mg!kglday residential)e 

0.026516 110