UN ITED STATES ENVIRONMENTAL PROTECTION AGENC Y WASHINGTON, D

. C

. 20460 

## UAY 0 5 2014

MEMORANDUM OFFICE OFCHEMICAL SAFETY ANDPOLLUTION PREVENTION
SUBJECT : BEAD Chemical P rofile (BCP) for Registration Review: Pyraflufen-ethyl (030090) FROM:

THRU : Sunil Ratnayake, Ph.D., Biologist Biological Analysis Branch Jihad Alsadek, Ph

.D., Economist Scienc e Informati on and Analysis Branch

_ 

# J

_**~** Andrew Lee, Ph.D., Economist

# ~**~** Economic Analys i s Branch Biological and Economic Analysis Division 503P) Amet Jones, Chief

# ~ rJ...,i) Biological Analysis Branch

# ~ 

# 7
Diann Sims, Chief Science Informati on and Analysis**Branch~ _**  Timothy Kiely, Chief

# ~**~** Economic Analys is Branch Biological and Ec onomic Analy s Division (7503P) TO: Steven Snyderma n , Chemical Review Manager Risk Management and Implementation Branch 3 Pesticide Re-evaluation Division (7508P)

Peer Review Panel Date : April 2, 2014

Page 1

### SUMMARY Pyraflufen-ethyl was first registered in the U.S. in 2002 and it is registered for the control of certain broadleaf weeds in many agricultural and non-agricultural use sites. Pyraflufen-ethyl is a contact type herbicide used as a defoliant in cotton and desiccant in pota toes to facilitate the harvesting of these crops. Also, pyraflufen-ethyl is used as a pre-plant burn-down, at plant before the crop emergence, and as a post-emergence treatment depending on the crop and stage ofthe crop growth. Based on private market usage d a ta from 2003-2012, usage averaged approximately 2,000 pounds active ingredient (a.i.) applied annually approximately on 654,000 acres. The average application rate over this time period was 0.003 pounds a.i. /acre

. Proprietary data show about 100 lbs. a.i. were used on turf and ornamentals in 2012. Based on the proprietary data, cotton, is the crop with highest us age and T exas, Georgia, California, and North Carolina were the states with higher usage of pyraflufen- ethyl. NASS usage data are not available for this herbicide for non-agricultural use sites. 

### INTRODUCTION The Biological and Economic Analysis Division (BEAD) Chemical Profile (BCP) provides an overview of the pest management roles and quantitative usage information for pyraflufen-ethyl. The BCP includes summaries ofprevious BEAD products and available public and/or private use and usage data for pyraflufen-ethyl to describe the role of this chemical in pest management. Additional information on use is available in the pyraflufen-ethyl LUIS Label Data Report. Information provided in this BCP may be used by stakeholders (e.g., users and registrants), OPP risk and benefit assessors, OPP risk managers, and the general public during the Registration Review process of thi s pesticide. 

### USE SITES Agricultural Use Sites The registered agricultural use sit es ofpyraflufen-ethyl include: tree nuts, grapes, pome fruits, stone fruits, dates, figs, mangos, loquat, persimmons, pomegranate s, kiwi, chicory, ginger, turmeric , cucurbits, fruiting vegetables, leafy vegetables, cole crops, root crops, beans, peas, lentils, com, barley, oats, rye, wheat, sugarcane, ginseng, flax, safflower, sunflower, canola, sugar beets, celery, cotton, mustard, olives, sorghum, soybeans, pastureland, conservation reserve program, and christmas trees. Non-agricultural Use Sites The registered non-agricultural use sites ofpyraflufen-ethyl include: ornamentals, grasses, ditch banks, uncultivated areas, vacant lots, airfields, rights-of-way, roadsides, railroads, lumber yards, industrial sites , storage areas, fen cerows, hedgerows , fenc es and commercial areas.
Page2FORMULATIONS AND APPL ICATION METHODS Pyraflufen-ethyl formulations include emulsifiable concent rate and liquid

. Pyraflufen-ethyl can be applied using ground and aeri al application equipment, but application of this product with any type of irrigation system i s prohibited.

HISTORY OF PYRAFLUFEN-ETHYL AND BEAD PRODUCTS Pyraflufen-ethyl is an herbicide registered for use in the U.S. since 2002 (USEPA, 2014). A Screening Level Usage Analy s is (SLUA) provides percent crop treated for many crops for which usage data were available (BEAD, 2013). For pyraflufen-ethyl, the agricultural sites with the greatest number ofpounds u s ed were on cotton
. In terms ofthe percent crop treated, tomatoes and cotton averaged 1 0 and 5 percent, respectively

. USAGE Agricultural Usage Based on private market usage data from 2003

- 20 1 2, usage averaged approximately 2,000 pounds active ingredient (a.i.) applied annually on approximately 654,000 acres treated. The average application rate over thi s time period was 0.003 pounds a.i./acre. Figure 1 represents pyraflufen

- ethyl usage in pound s a.i. over the 2003-2012 timeframe. Figure 2 represents total area treated in acres over the same timeframe (Proprietary Data, 2003

- 2012). FIGURE 

### 1. 

### raflufen-eth

Total Pounds AI

M 0 0 N
Source: Proprietary Data, 2003

- 2012 ..r 0 0 N 1.1) 0 0 N OJ:) 0 0 N

Page 3 r-. 0 0 N Years 00 0 0 N 0) 0 0 N 0 rl 0 N rl rl 0 N N rl 0 N

### FIGURE 2. P raflufen-eth I 

### Total Area Treated in Acres 2003-2012 1,400,000**.,--- ----** **------ ---** **----- ~--** 

Total Area Trea ed

0**+- --** **.-- -.** **-- -.** **-- -.** **--~- .-** **--.----. --** **-. -~**  ('\") 0 0 N """ 0 0 N

Source: Proprietary Data, 2003-2012 U'l 0 0 N ID 0 0 N ,..... 0 0 N Years**~** 0 N 0'1 0 0 N 0 .-4 0 N .-4 .-4 0 N N .-4 0 N



### Table 1. 

### Comparison of Crops with Highest Use of Pyraflufen-ethyl- Percent of Total Lbs. Applied (2003-2007 and 2008 -2012) 2003-2007 2008-2012 Average Annual = 1, 500 lbs/yr Average Annual = 1 , 8 00 lbs/yr 

### Crop %Lbs Crop %Lbs Cotton 91% Cotton 79% Fallow 3% Grapes, Wine 6% Wheat, Winter 2% Grapes, Raisin 3% Potatoes 2% Wheat, Spring 2% Source: Proprietary Data, 2003-2012. 

### Table 2. Comparison of States with Highest Use of Pyraflufen-ethyl- Percent of Total Lbs. Applied (2003-2007 and 2008-2012) 2003-2007 2008-2012 Average Annual Usage= 1,500 lbs/yr Average Annual Usage = 1,800 lbs!'yr 

### State %Lbs State % Lbs Texas 32% Texas 35% Georgia 23% California 22% California 12% North Carolina 16% North Caro lina 11% Georgia 14 % Source: Proprietary Data , 2003-2012 The major agricultural use ofpyraflufen-ethyl between both the 2003-2007 and 2008

- 2012 time frames was on cotton (9 1 % of total pounds app li ed in 2003-2007 , and on cotton (79% of total pounds applied 

### in 2008-2012) follo wed by fallow (3%) and winter wheat and potatoes (2% each) · in 2003

- 2007, and wine grapes (6%), raisin grapes (3%) and spring wheat (2%) in the 2008 -2012 Page4timeframe compared to the usage during the timeframe from 2003 to 2007. However, total pounds applied in cotton averages somewhat higher in the more recent time period and has been increasing

. Use on cotton is primarily as a defoliant. The average a.i. rate for the top crops 

### in terms of pounds a.i. app lied was the highest for grapes (raisins and wine) at 0.005 lbs. a.i./acre and the lowest for spring wheat at 0.001 lbs

. a.i./acre as shown in Table 3. Application Rates 

### Table 3. Pyraflufen-ethyl Use on Top Crops: Average A

.I
. Rate, 2008-2012 Crop Average Annual Average Total Acres Avg

. A.I. Rate (lbs Pounds Treated* a.i.!acres) Cotton 1,403 513,391 0.003 Wine Grapes 106 22,135 0.005 Raisin Grapes 46 9,626 0.005 Spring Wheat 25 28,647 0.001 *Total Acres Treated sums all acres treated for a crop, mcludmg those acres that rece1ve multiple treatments. Source: Proprietary Data, 2008-2012 Geographic Distribution of Pyraflufen-ethyl Use Agricultural Use Intensity ofPyraflufen

- ethyl Use in the U.S. Another measure of usage is the use intensity. In this analysis, the use intensity is expressed as the average annual amount (in pounds) ofthe active ingredient applied per 1,000 acres of crop acres grown . This differs from the application rate, which is expressed as the pounds a.i. applied per treated area. Figure 3 spatia lly represents pyraflufen

- ethyl use intensity in the United States. This may be due to the h igher production of cotton and grapes in Texas, California, Georgia and North Carolina

. For more information about this map, see Appendix A.

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### FIGURE 3.Annual average agricultural use intensity of pyraflufen-ethyl (2008-2012)

.

Pounds Active Ingredient per 1.000 Crop Acres Grown c::J NoData 

## D <o .ooo1

- 0

. 0007- 0

. 0023

- 0.0024- 0.0106

- 0.0107- 0.018

- >0.018 (Source: Proprietary Data) Non-Agricultural Usage Proprietary data show about 100 lbs. a.i. are used on turf and ornamental in 2011. There are no reported non-agricultural NASS usage data for pyraflufen-ethyl.


### BIOLOGICAL ASPECTS RELEVANT T O PYRAFLUFEN-ETHYL Pyraflufen-ethyl is a contact type herbicide belongs to th e phenyl pyrazole group of herbicides (Group 14). Herbici des in this group also identified as protox or PPO inhibitors. The mechanism of action ofthe herb i cides in this group is inhibition of the activity ofprotoporphyrinogen oxidase, an enzyme found in plant species. The inhibition ofthis enzyme in chloroplasts leads to subsequent cell membrane destruction and necrosis leading to the death o f susceptible weeds

.

Page 6ROLE OF PYRAFLUFEN-ETHYL IN PEST MANAGEMENT Pyraflufen-ethyl is registered for the control of susceptible annual and perennial broadleaf weeds in many agricultural and non - agricultural use sites described under the usa ge section of this document. Major agricultural use sites include: field com, cotton , potatoes , soybeans, wheat, and tomatoe s. The major non-agricultural use sites include: airfields, rights-o f-way, ro a dsides, rai lroads, lumber yards, industrial sites, storage areas , fencerows, hedgerow s, fences and commercial areas. Pyraflufen-ethyl can be applied as pre-plant bum-down , pre-emergence , and post-emergence treatments. It can be tank-mix ed with other herbicides such as dicamba to broaden the spectrum of weed control (University of California, 2014). Redroot pigweeds 

### (Ama ranthus retrojlexus), common lambsquarters 

### (Chenopodium album), kochia 

### (Kochia scoparia), prostrate knot weeds 

### (Polygonum aviculare), Russian thistle 

### (Sa/sola spp .) are some of the key broadleafweed species that can be managed by applications ofpyraflufen-ethyl (University of California, 2014). Pyraflufen-ethyl is also, used as a plant desiccant on potato and defoliant on cotton. App lica tions ofpyraflufen-ethyl on cotton increases the production ofethylene in cotton p lants causing the leaf abscission which facilitates harvesting of cotton. Also , it reduces the amount of inert matter mixed with the harvested cotton. Pyraflufen-ethyl is applied on potato as a harvest -aid treatment (desiccant) to dry the plant before digging t he soil for harvesting of potatoes. According to the International Survey of Herbic ide Resistant Weeds (ISHR W), only a single weed specie 

### (Ambrosia artemisiifolia) has developed resistance to the mechanism of action of pyraflufen-ethyl (Heap , Online Publication, Undated). Therefore , pyraflufen-ethyl can be used as a tool in resistance management programs; especially , for the management of weed species which have developed resistance to herbicides with different modes of action. For example, in South Carolina, use ofPPO-inhibitors is recommended for an excellent control ofALS (Acetolactate Synthase) and glyphosate-resistant Palmer amaranth biotypes (South Carolina Pest Management Handboo k for Field Crops , 2014). DATA NEEDS The Agency currently does not have important information on pyraflufen-ethyl. Obtaining the following information on agricultural crops that are registered but are not s urveyed, such as flax, and Christmas trees , and non-agricultural use si tes such as ornamentals , ri ghts

- of

- way , roadsides, railroads, lumber yards, industrial sites, storage areas, fencerows, hedgerows , fences and commercial areas may improve future assessments conducted by the Age ncy related to the use and importance ofpyraflufen -ethyl.

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### REFERENCES BEAD, 2013. Pyraflufen-ethyl Screening Level Usage Analysis. Biological and Economic Analysis Division, Office of Pesticide Programs, US Environmenta l Protection Agency. Apri l15 , 2013. Heap, I. Undated. The International Survey of Herbicide Re sistant Weeds

. Online Publication. Available at: www. weedscience.orhttp: / /www. weedscience.org/summary/M OA.aspx

.. Accessed on Jan. 22, 2014. Proprietary Data. 2003 -2012. South Carolina Pest Management Handbook for Field Crops. 2014. Available at: http: //www .clemson.edul extension/rowcrops/pest/fi les/20 14%20Pest%20management%2 Ofiles

.pdf /we e dcontrolincottonPMH2014.pdf

. Accessed on April18, 2014. University of California Pest Management Guidelines. 2014. Available at: http ://www.ipm

.ucdavis.edu/PMG /r730700411

. html. Accessed on March 14, 2014. USEPA. 2014. Federal Register. Online Publication. Available at: http: / /iaspub.epa.gov/apex/pesticides/f?p=CHEMICALS EARCH: 3 :0: :NO: I ,3,31, 7,12,25: P3 XCHEMICAL ID:3650

. Accessed on Apr il 11,2014. USDA, 2006-2010. NASS Crop Reporting Districts. Available at: http: //www.nass.usda.gov /Data and Statistics/County Data Files/Frequently Asked 

### 0 uestions/county list.txt. Accessed on March 14, 2014. USDA, 2007. Census of Agriculture. Available at: http: //www .agcensus.usda.gov /Publications/ 2007 / index.asp

. WSSA, (Weed Science of America), Undated. Summary of Herbicide Mechanism of Action. Weed Science Society of Amer ica. Available at: http ://wssa.net /wpcontent /uploads/WSSA-Mechanism-of-Action

. pdf

. Accessed on, J an. 16, 2014.

Page 8APPENDIX A The map included herein primarily for the use of the risk assessors in the Environmental Fate and Effects Division. The map provides a very broad geographical view of the amount (in pounds) of the active ingredient applied per 1,000 acres of"land in farms ". These data are included in the maps because risk assessors are interested in the amount of a pesticide used across farmland. Because of the definition of Land in Farms, as discussed below, the calculated values presented in the map are not equivalent to an application rate (lbs a.i. I A). The data used to make these maps have many limitations. Any interpretation of the maps should consider the underlying data and the assoc iated limitations carefully. The smallest areas shown on the maps within each state are Crop Reporting Districts (CRD). CRDs are defined by USDA and each consists of multiple counties that h ave similar soils, growing conditions, and farming practices. The CRDs within many states have roughly the same area. Because it is not feasible to conduct an agricultural survey that samples every county in the United S tates , the use of CRDs allow for a sample to be collected that represent a much larger area with relatively homogeneous agricultural characteristics. The numerator (annual average pounds applied) is based on private market surveys ofpesticide use in agriculture averaged over the last five years (Proprietary Data, 

### [dates]). These surveys cover about 60 crops and are targeted in states that produce the majority of the crop. Although the surveys capture most of the use of a particular active ingredient in agriculture, there are several limitations to these surveys.

• S tates with minor produc tion of a surveyed crop are not sampled • Not all typ es ofpesticides are surveyed in every crop in every year • Many spec ialty crops with very small acreages are not included in the survey The result of these limitations is that CRDs that show no usage may actually have a small amount ofthe active ingredient being used. The denominator (1 ,000 Acres of land in farms) was selected from the Census of Agriculture (USDA,2007) to represent agricultural acreage that is actively managed and includes most of the areas treated with pesticides. The category " Land in Farms" i s defined by the Census of Agriculture as being made up of four components: • Total cropland • Permanent pasture • Total woodland • Land in farmsteads, buildings, li vestock facilities, ponds, roads, wasteland, etc. This category includes land in the various USDA conservation programs. It should be noted that the Census of Agriculture does not include grazing land rented (on a per-animal basis) from the Bureau of Land Management or Forest Service, thus it is an underestimate of the land being managed for agricultural purposes. Page9The reader should pay particular attention to the figure legends and realize that a map prepared for a particular chem ical is not directly comparable to a map prepared for a different chemical. Scale and units of measurement do matter and may be different between maps.

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