# Page 1 of 6 OFFICE OF

CHEMICAL SAFETY AND

POLLUTION PREVENTION 

# UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON D.C., 20460



# PC Code : 270000

DP Barcode : 424792

Date: May 4, 2015

MEMORANDUM

Subject: Isofetamid: Haz ard Comparison Memo for Several Fungicides.

To: Cynthia Giles

‐ Parker, Chief

Tony Kish, Product Manager

Fungicide Branch

Registration Division (7505P)

Office of Pesticide Programs

From: Rosanna Louie

‐ Juzwiak

Environmental Risk Branch 3

Environmental Fate and Effects Division (7507P)

Office of Pesticide Programs

Through: Dana Spatz, Chief

Environme ntal Risk Branch 3

Environmental Fate and Effects Division (7507P)

Office of Pesticide Programs

The purpose of this memorandum is to provide supporting information to the proposed decision

document and ecological risk assessment for the proposed Section 3 uses of the new chemical

isofetamid, on almond, lettuce, grapes (Subgroup 13

‐ 07F), low gro wing berries (Subgroup 13

‐ 07G),

rapeseed (Subgroup 20A), and turf. The ecological risk assessment identified the potential for chronic

risk to birds and mammals, acute risk to listed estuarine/marine invertebrates, and chronic risk to fish.

There is uncertainty about potential chronic risk to aquatic invertebrates because effects occurred at all

test conce ntrations, and there is a narrow margin between the lowest test concentration and the

estimated environmental concentrations. Toxicity to terrestrial invertebrates ( i.e.

, honey bees) cannot

be assessed at this time due to the lack of data; therefore, there is uncertainty with the potential for risk

to these animals. In con trast, acute risk concerns were not identified for exposures to birds, mammals,

fish, freshwater invertebrates, non

‐ listed estuarine/marine invertebrates, or plants.

The Biological and Economic Analysis Division (BEAD) identified several fungicides 1 

# that may serve as

alternatives for the crop sites and pest spectrum on the proposed product labels. This analysis includes

the subset of fungicides (identified by the applicant) that can be replaced with an isofetamid application

1 

# USEPA, 2014, Selected Alternative Fungicides to Isofetamid Used on Almond, Grapes (and Crop Subgroup 13

‐ 07F),

Low Growing Berries (Crop Subgroup 13

‐ 07G), Turf Grass, Lettuce, and Rapeseed (Canola) [DP#421726]



# for

# Page 2 of 6 as part of a spray rotation schedule. This memorandum presents toxicity data for isofetamid and other

fungicides with respect to taxa that may be at risk as a result of the proposed uses of isofetamid. Tables

1 through 8 provide toxicity data on a chemical

‐ by

‐ chemical basis as they are available; chemicals are

generally ranked from the most to least sensitive endpoint. It should be noted that lower toxicity values

represent fungicides that are more toxic on a hazard basis; however, this analysis does not consider

exposures from their registered uses.

Table 1. Comparison of Mammalian (Norway rat, Rattus norvegicus ) Chronic NOAECs for Isofetamid

and Other Fungicides

Chemical

(PC Code) NOAEC

(mg a.i./kg

‐ diet) MRID

Boscalid

(128008) 100 45404906

Fluxapyroxad

(138009) 112 47923602

Iprodione

(109801) 150 42637801

Fluopyram

(080302) 200 47372441

Pyraclostrobin

(099100) 200 45596210

Penthiopyrad 680 47614906

47614907

Isofetamid

(270000) 1,000 49011940

Table 2. Comparison of Avian NOAEC Values for Isofetamid and Other Fungicides

Chemical

(PC Code) Organism NOAEC

(mg a.i./kg

‐ diet) MRID

Fluopyram

(080302) Bobwhite quail

Colinus virginianus 46.7 47372344

Fluxapyroxad

(138009) Bobwhite quail

Colinus virginianus <100 47923720

Isofetamid

(270000) Bobwhite quail

Colinus virginianus 276 49018423

Boscalid

(128008) Bobwhite quail

Colinus virginianus 300 45404925

Iprodione

(109801) Bobwhite quail

Colinus virginianus 300 00099126

Pyraclostrobin

(099100) Mallard duck

Anas platyrhynchos 1,061.5 45118427

Penthiopyrad

(090112) Mallard duck

Anas platyrhynchos 1520 47614983

Bobwhite quail

Colinus virginianus 5090 47614982Page3of6Table3.ComparisonofHoneyBeeAcuteContactandOralValuesforIsofetamidandOtherFungicidesChemical(PCCode)ContactLC50(uga.i./bee,unlessnoted)OralLD50(uga.i./bee,unlessnoted)MRIDIprodione(109801)N/AN/AN/APyraclostrobin(099100)TGAI:>100TEP(withboscalid):>32.9TGAI:>110TEP(withmetconazole):2.7TGAI:45118711TEP(withboscalid):48470202TEP(withmetconazole):47445001Fluxapyroxad(138009)TGAI:>100TEP:15.7(BAS70001F,withpyraclostrobin)TGAI:>111TEP:>32.4(BAS70302F)TGAI:47923748BAS70001F:48565301BAS70302F:47924317Penthiopyrad(090112)TGAI:>500TEP(Fontelis):23.5(96‐hours)TGAI:>500TEP(Fontelis):50.7(96‐hours)TGAI:47615016/‐17TEP:47615237Isofetamid(270000)TGAI:100TEP:>100TGAI:>30TEP:>100TGAI:49018426TEP:49018425Fluopyram(080302)TGAI:>100ugtestmaterialTEP:>83.2TGAI:>102.3ugtestmaterialTEP:>89TGAI:47372347TEP:47372348Boscalid(128008)>200ug/bee>166ug/bee45405019N/A=DataNotAvailableTable4.Estuarine/marineinvertebrateAcuteToxicityvaluesforIsofetamidandOtherFungicidesChemical(PCCode)OrganismEC50/IC50/LC50(mga.i./L,unlessnoted)MRIDFluxapyroxad(138009)EasternoysterCrassostreavirginicaIC50=0.9647923762Pyraclostrobin(099100)SaltwatermysidAmericamysisbahiaLC50:0.0041645118412Fluopyram(080302)SaltwatermysidAmericamysisbahia>0.5147372327Boscalid(128008)EasternoysterCrassostreavirginica1.0245405003Penthiopyrad(090112)EasternoysterCrassostreavirginica1.247615033Page4of6Chemical(PCCode)OrganismEC50/IC50/LC50(mga.i./L,unlessnoted)MRIDIsofetamid(270000)SaltwatermysidAmericamysisbahiaLC50:1.5149011998Iprodione(109801)EasternoysterCrassostreavirginica2.340489202Table5.FreshwaterFishChronicToxicityValuesforIsofetamidandOtherFungicidesChemical(PCCode)OrganismLOAEC(mga.i./L)NOAEC(mga.i./L)MRIDPyraclostrobin(099100)RainbowTroutOncorhynchusmykiss0.006420.0023545118421Fluxapyroxad(138009)CarpCyprinuscarpio0.042(ACR)0.022(ACR)ACRbasedon4792372447923729Isofetamid(270000)FatheadminnowPimephalespromelas0.180.08649018406Penthiopyrad(090112)FatheadminnowPimephalespromelas0.1880.10047614994Boscalid(128008)RainbowTroutOncorhynchusmykiss0.2410.11645405006Fluopyram(080302)FatheadminnowPimephalespromelas0.2690.13547372336Iprodione(109801)FatheadminnowPimephalespromelas‐‐0.2640550801ACR=acute‐to‐chronicratioN/A=DataNotAvailableTable6.FreshwaterInvertebrateChronicToxicityValuesforIsofetamidandOtherFungicidesChemical(PCCode)OrganismLOAEC(mga.i./L)NOAEC(mga.i./L)MRIDIprodione(109801)N/AN/AN/AN/APage5of6Chemical(PCCode)OrganismLOAEC(mga.i./L)NOAEC(mga.i./L)MRIDPyraclostrobin(099100)WaterfleaDaphniamagna0.0080.00445118419Penthiopyrad(090112)WaterfleaDaphniamagnaTGAI:0.818TEP:0.02075TGAI:0.471TEP:0.1061TGAI:47615003TEP:47615236Boscalid(128008)FreshwateramphipodHyalellaazteca>1.0660.29845405009Isofetamid(270000)WaterfleaDaphniamagna0.39<0.39L49018405Fluxapyroxad(138009)WaterfleaDaphniamagna0.950.4647923736Fluopyram(080302)WaterfleaDaphniamagna2.991.2147372334N/A=DataNotAvailableTable7.Estuarine/marineFishToxicityvaluesforIsofetamidandOtherFungicidesChemical(PCCode)OrganismLOAEC(mga.i./L)NOAEC(mga.i./L)MRIDBoscalid(128008)N/AN/AN/AN/AFluopyram(080302)N/AN/AN/AN/AFluxapyroxad(138009)N/AN/AN/AN/AIprodione(109801)N/AN/AN/AN/APenthiopyrad(090112)SheepsheadminnowCyprinodonvariegates0.8970.476ACRbasedon476149884761499447615034Page6of6Chemical(PCCode)OrganismLOAEC(mga.i./L)NOAEC(mga.i./L)MRIDIsofetamid(270000)FatheadminnowPimephalespromelas0.1810.0861490184061Pyraclostrobin(099100)SheepsheadminnowCyprinodonvariegates0.0240.0108454201011Thefreshwaterfishdatawereusedtoassessestuarine/marinefishforisofetamid.ACR=acute‐to‐chronicratioN/A=DataNotAvailableTable8.Estuarine/marineInvertebrateToxicityvaluesforIsofetamidandOtherFungicidesChemical(PCCode)OrganismLOAEC(mga.i./L)NOAEC(mga.i./L)MRIDBoscalid(128008)N/AN/AN/AN/AFluopyram(080302)N/AN/AN/AN/AFluxapyroxad(138009)N/AN/AN/AN/AIsofetamid(270000)N/AN/AN/AN/APyraclostrobin(099100)SaltwatermysidAmericamysisbahia0.000930.000546227601Iprodione(109801)SaltwatermysidAmericamysisbahia‐‐0.003540832201Penthiopyrad(090112)EasternOysterCrassostreavirginica0.3880.223ACRbasedon476149964761500347615033ACR=acute‐to‐chronicratioN/A=DataNotAvailable