UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

DEC 0 2 2014 

OFFICE OF CHEMICAL SAFETY 

AND POLLUTION PREVENTION 

MEMORANDUM 

SUBJECT: 

FROM: 

THRU: 

BEAD Chemical Profile (BCP) for Registration Review: Propanil (028201) 

Sunil Ratnayake, Biologist /1 · · - · \ 0 . 

Biological Analysis Branch L ~t Y\Cl ~ 

Sepehr 

Science 

Haddad, 

Information 

Environmental 

and Analysis 

Protection 

Branch 

Specialist H F~ ___. ~ 

Economic 

Stephen Smearman, 

Analysis Branch 

Economist 

~ 

). . I. ~ 

Biological and Economic Analysis Division (7503P) 

Arnet Jones, Chief 

Biological Analysis Branch 

Diann Sims, Chief ftl/h/}h II;/ dt;;:;;-~ ~~~-'- /)S . . Science Information and Analysis Branch 

Economic 

Timothy Kiely, 

Analysis 

Chief 

Branch 

2J It 

V\J\.. ~~ 

Biological and Economic Analysis vision (750 

TO: Susan Bartow, Chemical Review Manager, RMIB II 

Pesticide Re-evaluation Division (7508P) 

Peer Review Panel date: October 15, 2014 
SUMMARY 

Propanil was first registered in the U.S. in 1973 and it is an acetanilide belongs to the amide 

family of herbicides. Propanil is applied as a post-emergence herbicide to control certain grasses 

and broadleafweeds in rice production. This herbicide has no residual activity. A Reregistration 

Eligibility Decision (RED) was completed for propanil in 2003 and amended in 2006. 

Based on private market usage data from 1998-2012, usage averaged approximately 6 million 

pounds active ingredient (a.i.) applied annually on 1.8 million acres treated. The average a.i. rate 

over this time period was 3.34lbs a.i./acre. A Screening Level Usage Analysis (SLUA) was 

prepared by BEAD for this chemical in 2014 that provides the percent crop treated for rice. The 

SLUA which covers the 2004-2012 timeframe shows that on average 45 percent ofthe rice crop 

is treated with propanil. 

INTRODUCTION 

The Biological and Economic Analysis Division (BEAD) Chemical Profile (BCP) provides an 

overview of the pest management roles and quantitative usage infonnation for propanil. The 

BCP includes summaries of previous BEAD products and available public and/or private use and 

usage data for propanil to describe the role of this chemical in pest management. Additional 

information on use is available the Screening Level Usage Analysis (SLUA). 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 this pesticide. 

USE SITES 

Agricultural Use Sites 

Rice is the only registered agricultural use site for propanil. 

Non-Agricultural Use Sites 

There are no registered non-agricultural use sites for propanil. 

FORMULATIONS AND APPLICATION METHODS 

Propanil is formulated as an emulsifiable concentrate liquid, water dispersible granule (dry 

flowable), soluble concentrate liquid, and flowable concentrate liquid. Propanil is typically 

applied as a broadcast treatment with ground boom sprayers and aerial equipment. 

HISTORY OF PROPANIL and BEAD PRODUCTS 

A Reregistration Eligibility Decision (RED) was completed for propanil in 2003 and amended in 

2006. 

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A search of BEAD's Official Records database for BEAD benefits assessments specifically for 

propanil did not find any records of prior BEAD assessments, specifically for this chemical in 

the last 1 0 years. 

A Screening Level Usage Analysis (SLUA) was prepared by BEAD for this chemical in 2014 

that provides the percent crop treated for rice. The SLUA which covers the 2004-2012 

timeframe shows that on average 45 percent of the rice crop is treated with propanil. 

There have been no Section 18 requests for propanil in the last 1 0 years. An emergency 

exemption rriay indicate that there is a need for a particular chemical that is not registered for use 

on a particular site: An emergency exemption request may yield information about a particular 

chemical's importance or value that is not found in other EPA records. However, a lack of 

Section 18 assessments by BEAD does not specifically indicate the relative importance of the 

chemical. 

USAGE 

Agricultural Usage 

Based on private market usage data from 1998-2012, usage averaged approximately 6 million 

pounds active ingredient (a.i.) applied annually to rice on approximately 1.8 million acres 

treated. The average a.i. rate over this time period was 3.34lbs a.i./acre. Figure 1 presents 

propanil usage in pounds a.i., and Figure 2 shows total area treated in acres over the 1998-2012 

timeframe (Proprietary Data, 1998-2012). Figures 1 and 2 show that over this time period in 

terms of both pounds applied and acres treated there has been a gradual decrease in use from 

1998 through 2012. 

FIGURE 1. Propanil Usage on Rice in Pounds Active Ingredient (1998-2012) 

10,000,000 

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1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 

Years 

Source: Proprietary Data, 1998-2012 

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FIGURE 2. 

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Total Area of Rice Treated with Propanil in Acres (1998-2012) 

1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 

Years 

Source: Proprietary Data, 1998-2012 

Table 1. Comparison of Percent of Total Lbs. Applied to Rice (2001-2005 and 200 

2001-2005 2008-2012 

Average annual= 6.3 million lbs/yr Average annual= 4.95 million lbs/yr 

Crop I %Lbs Crop I %Lbs 

Rice I 100 Rice I 100 

Source: Proprietary Data, 2001-2012. 

8-2012) 

Table 1 shows that use on rice accounts for all pounds applied during both the 2001-2005 and 

2008-2012 timeframes. The average annual usage in pounds has decreased from 6.3 million lbs 

a.i. applied per year in the 2001-2005 timeframe to approximately 4.95 million lbs a.i. applied 

per year in the 2008-2012 timeframe, a decrease of more than 20 percent. 

Table 2. Comparison of States with Highest Use of Propanil- Percent of Total Lbs. 

Applied (2001-2005 and 2008-2012) 

2001-2005 2008-2012 

Average annual= 6.3 million lbs/yr Average annual= 4.95 million lbs/yr 

State %Lbs State %Lbs 

Arkansas 51% California 43% 

California 23% Arkansas 36% 

Louisiana 9% Louisiana 6% 

*Other 17% *other 16% 

TOTAL 100% TOTAL 100% 

*Other states in both time periods includes Mississippi, Texas, and Missouri. 

Source: Proprietary Data, 2001-2012 

As shown in Table 2, Arkansas, California and Louisiana are the three top states with the highest 

use of propanil accounting for more than 80 percent of total pounds applied in both timeframes, 

even though total pounds applied has decreased by approximately 20 percent between the two 

periods. 

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Application Rates and Percent Crop Treated 

The average a.i. rate for rice in terms of pounds applied was 3.53 lbs a.i./acre during the 2008-

2012 timeframe as shown in Table 3. 

T bl 3 P a e . ropam 'lU se on T C op rops: A verage A I R .. a t e, 2008 -2012 

Crop Annual Average Annual Average Avg. A.I. Rate (lbs 

Pounds *Total Acres Treated a.i./acres) 

Rice 4.95 million 1.4 million 3.53 lbs a.i./A 

*Total Acres Treated sums all acres treated for a crop, mcludmg those acres that receive multiple treatments. 

Source: Proprietary Data, 2008-2012 

Geographic Distribution of Propanil Use 

Figure 3 provides a very broad geographical view of the average annual amount (in pounds) of 

propanil applied per 1,000 acres of crop acres grown. California and Arkansas depict a highest 

use intensity of acres treated with propanil followed by Louisiana and Mississippi. Please see 

Appendix I for a more detailed explanation of the information presented on the map. 

Page 5 
FIGURE 3. Annual Average Agricultural Use Intensity ofPropanil (2008-2012) 

Pounds Active Ingredient 

per 1 ,000 Crop Acres Grown 

0 <0.3 

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- >55.4 

C]NoData 

Non-Agricultural Usage 

There are no non-agricultural uses of propanil. 

BIOLOGICAL ASPECTS RELEVANT TO PROPANIL 

Propanil is an acetanilide herbicide belongs to the amide family. It is applied as a postemergence herbicide to control certain grasses and broadleaf weeds in rice production. Propanil 

is not a systemic herbicide and it kills susceptible weeds with contact activity. 

The mechanism of action of this herbicide is not completely understood. Propanil seems to 

interfere with electron transport in photosystem II of photosynthesis (Herbicide Handbook, 

2014). In photosystem II, two water molecules are oxidized to form one molecule of molecular 

oxygen. Other reported effects of propanil on susceptible plants include inhibition of 

Page 6 
anthocyanin synthesis, RNA, and protein as well as adverse effects on the plasma 

membrane.(Devine et al., 1993). 

Propanil is rapidly absorbed by the foliage. There is limited translocation from treated foliage to 

other areas ofthe plant. Propanil is most effective when susceptible grasses and broadleafweeds 

are small and growing actively under favorable soil moisture and weather conditions (Starn 80® 

EDF Product Label, 2012). Application ofpropanil to susceptible weeds causes foliar 

desiccation and necrosis which can be observed within several days after the herbicide 

application (Herbicide Handbook, 2014). 

ROLE OF PROPANIL IN PEST MANAGEMENT 

Propanil is used as a post-emergence herbicide for control of grasses and broadleafweeds in rice 

production. Application of propanil controls barnyard grass (Echinochloa crusgalli) broadleaf 

signalgrass (Brachiaria platyphylla), crabgrass (Digitaria spp.), sesbania (Sesbania exaltata), 

curly indigo (Aeschynomene virginica), spikerush (Eleocharis spp.), and rice flatsedge (Cyperus 

iria) at the seedling stage (Arkansas Rice Production Guidelines, 2014). Propanil is ineffective 

against ducksalad (Heteranthera spp.), redstem (Ammannia coccinea), momingglory species 

(Ipomoea spp.), sprangletop (Leptochloa panicoides), and red rice (Oryza sativa), which can 

contaminate and reduce market price of rice grain. The development of Clearfield rice varieties 

with resistance to imidazolinone herbicides offers new options for red rice control in rice 

production (Webster & Levy, Undated). 

From 2004 to 2012 an annual average of approximately, 6 million pounds ofproponil was 

applied to about 1.8 million acres of rice. This is about 45 percent of the U.S. rice crop, 

suggesting that propanil is an important herbicide in U.S. rice production. 

According to the International Survey of Herbicide Resistant Weeds, biotypes of two weed 

species; bamyardgrass (Echinochloa crus-galli var. crus-galli), and umbrella sedge (Cyperus 

difformis) have developed resistance to the mode of action of propanil in the United States 

(Heap, undated). 

REFERENCES 

Arkansas Rice Production Handbook. 2014. Online Publication. Available at: 

http://www.arkansas-crops.com/wp-content/uploads/20 14/02/MP 192.pdf. 

Accessed on Oct. 8, 2014. 

BEAD. 2014. Propanil Screening Level Usage Analysis. Biological and Economic Analysis 

Division, Office of Pesticide Programs, US Environmental Protection Agency. 

Devine, M., S. 0. Duke, and C. Fedtke. 1993. Physiology ofHerbicide Action. Prentice Hall, 

New Jersey. 

Page 7 
Heap, I. Undated. The International Survey of Herbicide Resistant Weeds. Online Publication. 

2014. Available at: www.weedscience.org. Accessed on Oct.15, 2014. 

Proprietary Data. 1998-2012. (pesticide agricultural usage data). 

Red rice. (Undated). Online publication of Texas Agric. Experiment Station. Beaumont, TX. 

Available at: 

https://beaumont.tamu.edu/elibrary/StudyRiceContest/2011/Red%20Rice.pdf. Accessed 

on Oct. 6, 2014. 

Starn 80® EDF Herbicide Product Label. 2012. RiceCo LLC. 5100 Poplar Avenue, Suite 2428. 

Memphis, TN 3 813 7. 

USEP A.2006. Reregistration Eligibility Decision (RED) for Propanil (amended). 

Webster E. and R. Levy. Undated. Weed Management. Chapter 5, LSU AgCenter. Online 

Publication. Available at: 

http://text.lsuagcenter.com/MCMS!RelatedFiles/%7BF7E930BF-346A-45DA-A989-

37FE3DOBOF11%7D/Chapter+5+-+Weed+Mgmt.pdf. Accessed on Nov. 19,2014. 

Page 8 
APPENDIX I 

The map included herein is 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 average annual 

amount (in pounds) of the active ingredient applied per 1,000 acres of crop acres grown. These 

data are included in the maps because risk assessors are interested in the amount of a pesticide 

used across agricultural land. The calculated values presented in the map are not equivalent to 

an application rate (lb a.i./ A). 

The data used to make these maps have several limitations. Any interpretation of the maps 

should consider the underlying data and the associated limitations carefully. 

The numerator (annual average pounds applied) is based on private market surveys of pesticide 

use in agriculture averaged over the last five years (Proprietary Data, 2008-2012). 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. 

• States with minor production of a surveyed crop are not sampled 

• Not all types of pesticides are surveyed in every crop in every year 

• Many specialty crops with very small acreages are not included in the survey 

The result of these limitations is that states that show no usage may actually have a small amount 

of the active ingredient being used. In some cases the displayed use intensity may be distorted 

because the surveyed crops and the reported pesticide usage may not accurately represent the 

actual pesticide usage on the crops produced in the state. 

The denominator (1,000 crop acres grown) was also obtained from the same private market 

survey database. The "Crop Acres Grown" variable represents the total acres grown in a given 

state of all of the surveyed crops. This value is independent of pesticide usage and pesticide 

registration. It is important to note that the surveyed crops (about 60) are sampled from states 

that are major producers of each crop. Therefore, there are cases where the actual crop acreage in 

a state is higher than that reported by crop acres grown in the survey because either that state 

and/or crop was not included in the survey. 

The reader should pay particular attention to the figure legends and realize that a map prepared 

for a particular chemical is not directly comparable to a map prepared for a different chemical as 

the legend bins will likely be different. 

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