UNITED STATES ENVIRONMENTAL PROTECTION AGENCY W ASHIN GTO N , D

. C

. 20 4 60 

## JUN 

## 2 7 2012

MEMORANDUM

SUBJECT: BEAD Chem i cal Profile for Registration

FROM: Bill Phillips, Agronomist OFFICE OF CHEMICAL SAFETY AND POLLUTION PREVE N TIO N

Biological Anal ys i s Branch ,/ 

### Sepehr Haddad, E nvironmental Protection

# Specialist/~-./~ Sc ience Information and Analysis Branch / Derek Berwald , Eco nomi st

# ~ (\\__

# ~t 

# 'Y Economic Analys i s Branch 

# \_l)**~ ~**  Bio logical and Economic Anal ysis D ivision (7503P) THRU: Arnet Jon es, C hi ef Bio l ogical Anal ys is Bra Diann Si m s ,

# hi**ef~~** Sc ience Inf ormation and Analys i s Branch
T imothy Kiely , C hief

# ~V'v\.~ Economic Analy sis Branch \J 

# J Biological and Economic Analysis Division ( P) TO: Jill Bloom , Chemical R eview Manager Risk Manageme nt and Imp lemen tation Branch 2 Pes t icide Re-evaluation Division (750 8P)

Product Review Panel date: May 8, 2012 INTRODUCTION The purpose of this docum ent is to convey usage informati on and a broad overview of the pest management roles of pesticides that are beginning to und ergo registration review. The anticipated audience consists of the t eam of EPA staff currently evaluating the registration status of2,4-D , and eve n tuall y the general pu bl i c. This document builds upon the data already provided

1by B EA D. The document is based on information and data available to BEAD as of May 5, 20 1 2. Use pattern s may chan ge in resp onse to future conditions and market opportunit ie s. The herbicide 2,4-D has a l ong hi story of efficacy research dating back to the early 1940 's where it was evaluated in agricultural se ttings a s well as on turf ; including the lawn of the Whi te Hou se where it was tested for the control of dand e lion s ( Tar axacum officina/e). Following the initial entry of 2,4 -D into the market p l ace in 1946 this h erb ic id e was qui ckly adopted by farmers and has bee n a staple of agricultural weed contro l since. 1 In fact, in the 2007 rankings of use based on total pounds active ingredient (lbs ai) , 2, 4-D was ranked number seven amon g all crop protectants and number five for h erbicid es u se d in agriculture. In hom e and garden use it ranked number one, and was numb er o ne in commerci al, governmental, and industrial 

### use? In add ition to the uses as an herbicide , 2,4 -D is also used as a growth regulator in c itrus. Thi s herbic ide i s an auxin

- like p lant hormone with the mechanism of action like that o f the in vivo plant growth regulator ind o le acetic acid. 2,4 -D effects its control on weeds vi a disrupting the flow i n the vascu lar sys te m . This flo w i s d is rupted i n two ways, elo ngation of plant cells which results in cons tricted and twisted of the stems, and swelling at the nodes (e.g., leaf attachm ents). 2,4- D as an herbicide is used in many agricultural c rops and is applied postemergence to the weed species , preemergence to broadleaf crops, and preemergence and early po ste mergence in some grass crops. In addition to agricultural u ses, 2,4 -D i s used t o control wee d s in non agricultural and industr ial u se s ite s. There are currentl y nin e diff erent sy nthetic auxin resistant weed species r ep orte d in the Unite d States. Som e of these weed species are considered problematic in crop producti on. Th e Weed Scienc e Society of America cl ass ifies thi s herb icide in th e m echani s m of action group 4

. 3 Formulations of2, 4-D are emu lsifiabl e co ncentrate, gr anul es, sol uble concentrate/solid , water d i spers ibl e granul es , and wettable powder. 2 ,4 -D may be app li ed wit h a wide range of application equipment including fixed-wing aircraft, backpack sprayer, band sprayer , boo m sprayer , g ranule appl i cator, ground-dire cte d s prayers , hand held sprayer, helicopter, injection equipment, tr actor-mo unted g ranule appli ca tor, and tra ctor-mount ed sp ray ers . Overall , the primary agri c ul tura l crop use s f or 2, 4-D is for sel e ct i ve broadleaf weed control in past ureland, wheat and com. In non-crop are a s the primary use of this herbicide i s i n home l awn care and golf co ur se weed contro l. Becau se of the many l awn and turf s pecies to which 2,4

- D can be app li ed , it is very useful for controlling broadl eaf weeds in many grasses. Added to its fle x ibility and efficacy is i ts relative ly low cost. From 200 6

- 20 1 0, agricu l tura l use of2 , 4-D was l ess expensive (under $2.00 per acre) than other broad spectrum herb i cides like glyphosate (over $6

. 00 per acre) o r paraquat (ov er $7.00 per acre), although they are not direct substi tutes.

1 Indu s try Task Force II on 2,4-D Resea rch D ata. http: //www.24d.org/ 2 EP A, P est ic ides Indu stry Sales and .Usage, 2006 and 2007 Marke t Es timates. http ://www

.epa . gov/ oppOOOO 1 /pestsale s/ 07pestsales/ market

_ estimates20 0 7.pdf 3 H erbicide Res istant Action Committee http: //www.hracglobal.com/Publications/ClassificationofHerb icidcModeofActionltabid/222 / Default.as px
2It was also cheaper than herbicides in general, which had an average cost for an herbicide tre atment of over 

### $7.50 per acre4

. In addition to the agricultural u ses, there are other uses for 2,4-D as a growth regulator in citrus. As a growth regulator it is applied pre -harvest to oranges and po st-harve st to lemon s. The growth regulator is applied to oranges prior to harvest in order to delay fruit drop. This is accomplished by using the chemical to inhibit the formation of an abscission layer between th e tree branch and the ripened fruit. By inhibiting the abscission layer the fruit can remain on the tree to continue to grow higher quality fruit. 5
The post harve st application of2 ,4-D to lemons relie s on the same basic physiological function as it does for the orange crop , however this done for a different reason. In the case of postharvest applications to lemon s the abscission layer b etw ee n the "button," a small brown stem attachment (calyx) , and the stem end ofthe fruit are kept attached. By retaining the button on the end of the fruit the incidence of Alternaria fruit rot is greatly reduced. The method of application for this use of2 , 4-D is by applying 2,4-D at 

### 500 ppm in a wax and water emulsion. This emulsion is applied to the fruit following the final rinse.

USE SITES Agricultural Use S ites The chemical2,4-D is an herbicide regi stered for many agricultural use sites including bushberries, caneberries, strawberries, grapes, citrus, nut c rops , pome fruits, stone fruits, hops , cucurbits, root crop vegetab l es, sweet corn , com, asparagus, forage grasses (including tho se for hay and silage), uncultivated agricultural areas, fora ge legumes, grain crops (such as rice, barley , oats, wheat rye, etc.), sugarcane , corn, sorghum, buckwheat, soy beans , cotton, peanuts and crops grown for oil (safflower , $unflower , rapeseed). Non-Agricultural Use Sites Non-agricultural use sites for which 2 ,4-D is registered includes forest trees , ornamental plants , ornamental lawn s and turf, ornamental- trees , woody shrubs and vines, domes tic dwellings, aquatic sites (ditch banks , irri gation systems , lakes , ponds etc.), wide area and general indoor / outdoor treatments (vacant lots, hedgerows, fence rows etc.) , commerc ial industrial and institutional maintenance (schools, hospital s, warehouses, airports, parks, etc.).

USAGE Agricultural Usage

4 Proprietary Data , 2000-20 I 0 5 Zur, A. and R. Goren. 1977. Reducing preharvest drop of 'Temple ' orange fruit s by 2,4-D

- Role ofcellulase in the ca l yx abscission zone . Scientia Hort. 7:237-248. http: //www . sciencedirect.com/science / article/pii/ 0304423877900206

3Based on private market usage data from 2000-2010, usage averaged approximately 29 million pounds active ingredient (lbs a.i.) for 55 million acres treated. The private market usage data available presents the data as just 2, 4-D (2,4-dichlorophenoxyacetic acid) and does not break down the data into the various salts and esters of2 , 4-D. The 2,4-D task fo rce has supplied the Agency with a master label in w hi ch they describe the 2,4-D chemica l forms they are supporting , which does include the various salts and esters. Figure 1 presents usage of 2 ,4-D in lbs a.i. and total area treated in acres over this t ime period. The average a.i. rate during the 2000-2010 time period was approximately 0.53 lbs a.i./A (acre); however, for individual us e sites the average a.i. rate over this same time period ranged from 0.1 lb s a.i ./ A to as high as 1.0 lbs a.i ./ A (0.1 lb s a.i ./ A for caneberries; 0.43 lbs a.i ./ A for winter wheat and fa ll ow; 0.49 lbs a.i ./ A for com and soybeans to as high as 1.0 lb s a.i ./ A for cherries , and pears)(Proprietary Data, 2000 -2010).

FIGU RE 1

. 2,4 -D Usage in Pounds AI. App li ed & Total Area Treated in Acres 2000 -2010 90,000,000**Pounds** AI

- Tot a l Area Treated {in Acres)
20,000,000 

# 8 8 8 8 8 8 8 8 

# g 8**~** N N N N N N N N N N N Years

Source: Proprietary Data, 2000

- 2010 Table 1 compares the states with the most agricu ltural usage between the 2001

- 2005 and 2006- 2010 timeframes, and Table 2 compares the crops with the highest use between those same time periods. These two timeframes were chosen since the Reregistration Eligibility Decision Document (RED) for 2,4-D was issued in 2005, and a comparison of the data before and after the issuance of the RED may have resulted in the changes in usage (Tables 1 and 2).

4TABLE 1. Comparison of States with High est Use of2,4-D- Percent of Total Lbs. Applied and Percent ofTota l Area Treated (Acres) Between the 2001-2005 and the 2006-2010 Timeframes 

### 2001-2005 2006-2010 State %Lbs %TAT Texas 14 Oklahoma 9

Kansas 8 Montana 7 N. Dakota 5 Arkansas 4 S. Dakota 4

Illinois 4 Nebraska 4

Other 42

.. Average Lbs A.I ./ yr = 30 m1lhon Average TAT (Acres)/yr = 58 million 13 7 g 11 7 3 4 4 4 39 State %Lbs %TAT Texas 12 1 1 Kansas 10 12 Oklahoma 8 7 Montana 5 8 Mississippi 4 3

Colorado 4 6

Illinoi s 4 4 Missouri 4 3 Indiana 3 3

Other 46 44 Average Lbs A.l./yr = 28 million Average TAT (Acres)/y r 

### = 54 million
TABLE 2. Comparison of Crops with the Hi ghest Use of2 ,4-D- Percent ofTotal Lbs. Applied and Percent of Total Area T reat ed (Acres) Between the 2001-2005 and the 2006-2010 Timeframes 2001-2005 2006-2010 Crop %Lbs 0 /o TAT Pasture land 44 35 Winter 12 IS Wheat

Corn 10 11 Spring 8 12 Wheat Soybeans 7 8

Fallow 6 9 Sorghum 3 4

Barley 

# z 3 Cotton 2 1 Other 5 4 Average Lbs A.I ./yr = 30 mtllion Average TAT (Acres)/yr = 58 million Source: Proprietar y Data , 2001-2010 Crop %Lbs %TAT Pasture land 33 25 Winter 14 18 Wheat Corn 13 14 Soybeans 12 12

Fallow 9 10 Spr ing 6 9 Wheat Cotton 3 3 Sorghum 3 4 Sugarcane 2 1 Other 

### 5 4



### .. Average Lbs A .l./ yr = 28 m1lhon Average TAT (Acres)/yr = 54 million

The states with the highest use in both the 2001

- 2005 and the 2006-2010 timeframes were Texas , 

### Oklahoma, Kansas and Montana whi le the sites with the highest us e in terms of total pounds applied in both timeframes were pasture land, winter wheat , and corn. These three highest use

5states are those with so m e of the highest amo · unt of pastureland , two of which are major wheat producin g sta te s. The "oth er" s tates dep icte d in Table 1 included more than 30 other states. There was a s lightly l ower average use in the latt er period with the top four states re maining the same, although the r elative rankin g has changed. Other states u sed re l atively small shares of th e nati onwide use of2 ,4-D. The "oth er" crops depicted in Table 2 included more than 40 ot h er crops. The s hare of2,4-D u se on past ure land declined considerably from th e 20 01-2005 to t he 20 06 -2 010 t im eframes. Overall use did n ot decline as much , because of small increases in crops with sub stant i al acreages , like w h eat , corn , a nd soybeans

.
N on-Agricultural Usage In terms of non-agricultural u sage, as pre se nted in Table 3, d ata are available for u sage by lawn care operators (LCO's) and co n sumers, and for uses such as go lf**~ourses,** lands cape , nursery/ greenhouse, turf farm s , and aquatic areas , although all data are not avai lable for each year. Usage o n gol f courses and by LCO ' s has remained fairl y steady, u se on in s titutional turf and land scape has fluctuated , and use in turf farm s has decreased s ubstantially ; however, lim ited data make s it impossible to be definiti ve in these cases. Th e most non -agricultural usage in terms of pounds a.i. applied as reported in 2003 and 2005, was by co n s umers for lawn us e , direct application or as a fertilizer combination

.

Table 3. 2,4-D Reported Non-Agri cultur al Usage (Pounds A.I.) (2002-2006) 

### Site 2002 2003 2004 2005 2006 Golf Course s 3 11 , 000 333 , 000 37 4 ,000 In stitut ional Turf 582 , 000 966 , 000 791 , 000 Lan d scape 375,000 193 , 000 262,000 Lawn Ca re Operators 2,350,000 2,512 , 000 2 , 145 , 000 T urf F arms 1,400 , 000 16 2 , 000 414 , 000 Nursery/ Greenhouse 900 70,000 8 , 000 Aquatic Areas 820 , 000 460 , 000 Cons umer -Lawn 1,830,000 915 , 000 Cons umer-Fertilizer 6,400,000 8,100 , 000 Combination 

### TOTAL Reported (lb s. a.i.) 5,0 19 , 000 9,05 0 , 000 4,206,000 9 ,475, 000 3,994,000 Sha ded areas of the table are tho se years for wh1ch there were no reports tss ued for the non-agncultural use s1te category Source: Klin e & Co., 2002-2006



### HISTORY OF BEAD ASSESSMENTS FOR 2,4-D Ther e have been few B E AD assess m ents for 2 , 4-D over the years. This is somewhat surprising , as 2 , 4-D h as been th e su b je c t of a recen t petition for cancellation and revocation of tolerances ,

6which was denied 6

. Public comments received during the petition process requested an alternatives assessment for 2 , 4-D. The asses s ment was not done , because no risks of concern were identified in evaluating the petition7

. Based on the 2007 ranking s ofuse, in totallb s ai , 2,4-D is an important herbicide u sed in agriculture , commercial, goverrunental , and industr ial use . Although BEAD h as not estimated the benefits of2,4-D, it i s reasonable to think the benefits wouJd be considerable , because it is used on a very large acreage, and is a relat ively low cost herbicide

.
INFORMATION THAT MAY BE USEFUL FOR BEAD 'S FUTURE WORK ON 2 ,4 -D Non-agricultural usage information (such as for lawn care op erators, consumers, and aquatic uses) after 2006 would be helpful in determining if these sites remain a significant part of the 2,4-D market.

REFERENCES Proprietary Data, 2000

- 2010 USDA, 2006-2010. NASS Crop Reporting Districts

. Online : http: //www.ers.usda.gov/briefing/arms/resourceregions /resourceregions.htm # nas s . US DA, 2007. Census of Agriculture. Online: http: //www .agcensus.usda. gov /Publications/ 2007 / index. asp

6 Bradbury, Ste ven P ., EP A Denial of Nove mb e r 6, 2008 NRDC Petition to Cancel All2,4-D Registrations, Jetter dated April? , 20 12. http :// www . epa.gov/pesticide s/ chem search / reg action s/ 24d/24d- fifra-respon s c. pdf 7 Wo lf, Joe l and Richard Kei gwin, EPA Response to Issues Rais ed in Publi c Comment, but Unrelated to Issues in NRDS 2,4-D Petition, April 07 , 2012. Available here: h ttp :// www.regulat io ns. g ov / #!docu men tD etai i :D= EPA-HO-OPP-200 8-0 8 77

- 0448

7Appendix 2,4-D Agricultural Usage by Crop Reporting District (2006 - 2010) Another measure of u sage is the use intensi ty. In thi s analy s i s, the use intensity is expre ssed 

### as the pounds a.i. applied per acre of land in farms

. This differs from the application rate, which is expressed as the pounds a.i. applied per trea ted acre . Figur e 2 spatially represents 2,4 -D use i ntensity in the US, with the most intense use in the areas depicted in the color red.
F IGURE 2. 2 ,4 -D Agricu ltur al Usage by Crop Reporting District (2006-2010)

2 ,4·0 Use (2006·20 I0) by Crop Reporting Distr ict Average Pounds per 1,000 Acres of Farmland

'Sources : - < 19

- 19-44 0 45

- 85

- 8 6

- 1 4 5

- 146-250

Proprietary Data

. 2006-2010 USDA, 2006-2010. NASS Crop Reporting Districts

.. USDA, 2007. Census of Agriculture. This is a map of agricu ltural pesticide usage at the Crop Reporti ng Dis t rict (CRD) level. CRDs are boundaries created by USDA NASS whi ch are aggregate s of counties (USDA, 2010). Pesticide usage is displayed as average poun ds (for the years 2006-2010) per I , 000 acres of farmland in a CRD to normalize for the variation in farmland between CRDs. Farmland acreage was obtained from USDA (2007). Us age is based on private market surveys of pesticide use in agriculture (Proprietary Data, 2006-2010). The survey data are limited to the states that represent the top 80-90% of acreage fo r the individual crops, therefore , use may be occurring in regions outs ide the scope of the survey. CRDs show in g no usage o f pes ticides may be due to either the lack of pesticide use in the r egion or nonparticipation in the agricultural surveys . In addition , across the years, ther e may be variations in the specific crops included in the CRD survey. This may result in a lower annual average fo r th e CRD

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