U NI TED STATES ENVIRONMENTAL PROTECTION AGE N CY WA SH I NGTON , D.C. 2046 0 

### APR 15 

## 2014

MEMORANDUM OFF I CE OF CHEM I CAL SAFETY AND POLLUT I ON PREVENT I ON



### S UBJECT : BEAD Chemical Profile (BCP) for Registration Review: Etridiazole (PC 084701) 

### FROM :



### THRU :

TO: Leonard Y ourman, Plant Pathologist

## ~~...c,...-'"1~..__;........---..-­ Biological Analysis Branch

# ~~ Rafael A. Prieto , E nvironmental Protection Specialist Science Information and Analysis Branch S tephen Smearman , Economist Economic Analysis Branch

# ~~ Biologica l and Economic Analys i s Divi sion (7503P) Amet Jones, Chief Biological Analysis Branco Diann Sims, Chief

# ~ Science Information and Analysis Branch Timothy Kiely , Chief 

# Sl \;\A

# ~ Economic Analysis Branch Biologica l and Economic Analysis ivision (750 ) Margaret Hathaway , Chemical Review Manager Risk Management and Implementation Branch 4 Pesticide Re-evaluation Division (7508P)
Peer Review Panel date: March 19 , 2014INTRODUCTION The Biological and Economic Analysis Division (BEAD) Chemical Profile (BCP) provides an overview of the pest management roles and quantitative usage information for etridiazole. The BCP includes summaries of previous BEAD products and available public and/or private use and usage data for etridiazole to describe the role of this chemical in pest m an agement. Additional information on use is available in the etridiazole PRD Label Data Report
. Information provided in this BCP may be used by stakeholders (e
. g., users and registrants) , OPP risk assessors, and OPP risk managers, and the general public during the Registration Review process ofthis pesticide.
USE SITES According to BEAD information sources, cotton is the only agricu ltural crop for which etridi azo le is used. Etridiazo le**(Terrazo le** **~** has a federal registration fo r use on ornamentals, go lf course turf, nursery stock, cotton, and tobacco. In addition, there are several states with Special Local Need (SLN) 24c labels for use in greenhouse tomato production
. FORMULATIONS AND APPLICATION METHODS This chemica l is formulated as a wettab le powder, emulsifiable concentrate, so luble concentrate (liquid), and granular.
HISTORY OF ETRIDIAZOLE and BEAD PRODUCTS Etri diazole was registered for use in the U .S. in 1962 , for control of damping-off, root rot and stem rot caused primarily by species ofPythium. A Screening Level Usage Analysis (SLUA) was prepared by BEAD for this chemical in 2014 that provides percent crop treated for cotton for which usage data was available. Use for cotton over the SLUA timeframe (1998-2011) accounted for l 00% of the agricultural etridiazo le usage. However thi s usage represents only 1.2% crop treated for cotton harvested acres , which may mean low benefits overall to cotton growers. However , uses limited to certain cotton production locations might indicate some useful attributes of etridiazole, although BEAD does not have supporting information for this possibility. A search ofthe BEAD data base found that there are no records of prior BEAD benefits assessments or emergency exemption requests for etridiazole. Note that a lack ofe mergency exemption requests for BEAD to review as part of the emergency exemp tion process for this chemical do es not specifically indicate the importance of the chemical.

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### USAGE Usage Trends For the ye ars 1998-2012 , etridiazole annual agricultural usage averaged 23 , 000 pounds of active ingredient (a.i.) treating an average of 126 , 000 acres , for an overall average application rate of 0.1825 pound s a.i
. per acre. Use in terms ofboth pounds a.i. and total area treated peaked in 2000 , and has been steadily declining until the most recent year s for which data are available (Proprietary data , 1998-2012). 

### Fi ure 1. 

### Etridiazole Total Poun ds and TAT in Acres on Cotton 1998-2012

0 00 0\ 0 .-4 N m**~** IJ) \0 ,.... 00 0\ 0 .-4 N 0\ 0\ 0 0 0 0 0 0 0 0 0 0 .-4 .-4 .-4 0\ 0\ 0 0 0 0 0 0 0 0 0 0 0 0 0 .-4 .-4 N N N N N N N N N N N N N Year
Source: Propri e tary Data , 1998-20 12. 70,000

0 - T AT (acres)

...... L bsA I

Based on proprietary data, 100 percent of etridiazole use is on cotton. This chemica l 's usage both in terms of total pounds and total area treated are in decline.



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### Table 1. 

### Comparison of States with Highest Use ofEtridiazole on Cotton- Percent of Total Lb A 

## r dB h 1998 2002 d 2008 2012 T' f 

### s. ,pplie etween t e - 

### an 

## - 1me rames 1998

-2002 2008-2012 State %Lbs State %Lbs M ississ ippi 32 Miss
. issippi 51 Louisiana 19 North Carol ina 27 Tenn essee 1 3 Texas 22 Arkansas 12 Alabama 8 North Carolina 7 Texas 6 Source: Propnetary Data, 1998-2012. Ap plica tion Rates 

### T bl 2 Et
.d. I U

a e 

# . ri 

### 1azo e se on 

# c otton: A

### verage p 

### d TAT oun s, , andAIR ate 

# . . Years Average Pounds Average Total Acres Treated Avg. AI Rate (TAT)* (lbs a.i./acres ) 1998-2002 47,000 252,000 0.186 2008-2012 800 4,000 0.188 *Total Acres Treated sums all acres treated for a crop, mcludmg those acres that rece t ve multtple treatments . Source: EPA Proprietary Data, 1998-2012 Non -Agricultural Usage BEAD information indicates 14 ,000 lbs etridiazole used on U.S. turf and ornamental uses for 2012. (EPA Proprietary Data, 2012) 

### ROLE OF ETRIDIAZOLE IN PEST MANAGEMENT Etridiazo le is a thiadiazole fungicide, classified b y FRAC as a Group 14 fungicide (FRAC, 2013). The mode of action has not been definitively identified, although FRAC information indicates that it may work by damaging cell membranes through lipid peroxidation (FRAC, 2013)
. Etridiazole may be used to treat soil in-furrow prior to p lanting cotton, especially where cotton has been planted year after year and where damping

- off is known to be a problem. It is also used to treat tobacco transp lants in greenhouse or outdoor float-bed systems. Etri diazo le is used to manage the soil borne pathogen Pythium spp., which causes damping off and root rot of seedlings. It acts as a protectant contact fungicide and may have curative properties against Pythium for tobacco transplants. Several SLN la bels are in effec t to tr eat Pythium root rots in greenhouse to mato production. Mefenoxam may be used similarly to manage Pythium damping

off for soi l and transplant treatments and seed treatments wi th metalaxyl or azoxystrob in may be used to protect agai ns t damping-off. Many soil and seed treatments contain additional active ingredients to manage other important pathogens s uch as Fusarium spp . 

### DATA NEEDS The Agency currently does not have extensive information on etridiazol e. Obtaining information may be usefu l for non-agricultural sites. In addition , information on specific attributes of
4etridiazole , fo r example on cotton, may improve future benefits or impact assessments if risk i ss ue s are found to exist. 

### REFERENCES FRAC. 20 1 3. List of Plant Pathogenic Organisms Res istant to Disease Control Agents. Fun g icide Resistance Action 

### Committee. http: //www.frac.info/publication/anhang/List%20of0/o20resistant%20plant%20pathogenic %20organisms February%202013%20updated.pdf EPA Proprietary Data, 2012. Proprietary Data. 1998-2012.



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