UNITED STATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON D.C., 20460

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MEMORANDUM
SUBJECT: Use Characterization for Atrazine OFFICE OF CHEMICAL SAFETY AND POLLUTION PREVENTION

FROM: Sepebr Haddad, Environmental Protection Specialist 

# jq-'**~** Science Information and Analysis

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THRU: Bill Phillips, II, PhD, Agronomist 

# pop..- Biological Analysis Branch Diann Sims, Chief

# <O~ Science Information and Analysis Branch Arnet Jones, Chief

# ~ Biological Analysis Branch Biological and Economic An ysis Divisi n TO: James Hetrick, Senior Scientist Environmental Fate and Effects Division (7507P) BEAD ProductReview PanelDate: March 7, 2012 INTRODUCTION Inthis memorandum, BEAD is providing EFED anatrazine use characterization for use intheir risk characterization document inpreparation for the June 2012 Science Advisory Panel (SAP) meeting on atrazine. The information inthis memo includes: a listing ofagricultural and non-agricultural use sites; common formulations; application methods, and application timing for the crops withthe highest use (corn, sorghum and sugarcane); agricultural usage data (typical use patterns, an updated screening level estimate ofagricultural uses for all crops for which data were available, and national mapping data); and non-agricultural usage information for which datawere available. The Appendix to this memo is an aggregated report which includes detailed label use and application information for atrazine.Information onuse sites, formulations, application methods, and applicationtimmg inthis section ofthe document has been obtained from various EPA sources including the 2006 Atrazine Reregistration Eligibility Decision (RED) document, databases such as OPPIN and the Label Use Information System (LUIS), and confirmed through a review oflabel information. Agricultural Use Sites

. Atrazine is , a triazine herbicide first registered in 1958. Atrazine is currentlyregistered for use against broadleafand some grassy weeds in com, sweet com, sorghum, soybeans, sugarcane, wheat, oats, macadamia nuts, guava, and range grasses. Application in wheat is to wheat stubble on fallow land following wheat harvests when the land is not cultivated; and therefore, wheat is not the target crop. Application to range grasses is for the establishment ofpermanent grass cover on rangelands and pastures under USDA's Conservation Reserve Program (CRP in OK, NE, TX, and OR) and range/pastureland. Most ofthe atrazine applied to com and sorghum is applied preemergence. Non-Agricultural Use Sites Atrazine is registered for use in conifer forests, Christmas tree farms, sod farms, ornamental grasses, ornamental plants, ornamental 

### turf, outdoorresidential (given the specific nature ofthe lawn uses, much ofatrazine's use on lawns is confined to Florida and the Southeast), schools, parks, playgrounds, and athletic fields. Atrazine can also be used onroadsides, rights-of-ways, airfields, vacant lots, roadsides, lumber yards, agricultural buildings, industrial sites and storage sites. Formulations: Atrazine is available in many formulations including granular, wettable powder, water dispersible granules, emulsifiable concentrate, flowable concentrate, soluble concentrate, readyto-use solution, and water soluble packs. Application Methods: Atrazine may be applied by groundboom sprayer, aircraft, tractor-drawn spreader, rights-of-way sprayer, lowpressure handwand, backpack sprayer, lawnhandgun, push-type spreader and belly grinder (hand-crank spreader).
. Application Timing on Crops Withthe Highest Use: Com: Applications to com are most oftenpreemergence (mid-April through mid-May in the major com growing areas). Posteinergence applications are most likelyto occur up to the end of June, until comreaches 12" inheight. There will be some variability intiming based on geographical regions. Sorghum: Applications to sorghum are most often preemergence (mid-May to mid-July inthe major sorghum growing areas). Postemergence applications are most likely to occur up to the end ofAugust. There will be some variability intiming based on geographical regions.

2Sugarcane: Applications to sugarcane are usually at planting (fall), inthe spring after emergence, and an additional postemergence application ' (often at layby). However, these later applications are only used ifpestpressure dictates. Also, ratoon crops may face heavier weed pressure, and therefor.e additional applications are more likely in sugarcane ratoon crops.


### AGRICULTURAL USAGE DATA Based onprivate market survey data from 2000-2010 usage averaged approximately 72 million pounds active ingredient (a.i.) for 71 million acres. Figure 1presents atrazine agricultural usage inpounds a.i. (lbs. ai) applied between 2000 and 2010. 

### FIGURE 1. Atrazine A ricultural Usa e lied 2000-2010 100,000,000 ,---------------------

50,000,000 -i--.---.----.---r---.---,----,---r--.,...---.,....-----, 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 Years Source: Proprietary Data, 2000-2010 Screening Level Usage Analysis Data (2003-2010) Table 1provides the mostrecent Screening Level Usage Analysis (SLUA) prepared in November, 2011. The SLUAprovides available estimates ofpesticide usage data for atrazine on agricultural crops inthe United States. The reported usage data inthe SLUA are obtained from various sources and are merged, averaged androunded so that the presented information is not proprietary, or business confidential. SLUA data sources include USDA-NASS (United States Department ofAgriculture's National Agricultural Statistics Service) (2003-2010) and Private Pesticide Market Research (2003-2010). These results reflect amalgamated data developed bythe Agency and are releasable to the public. Limitations to the data are: • Additional registered uses may existbut are not included because the available surveys do notreport usage (e.g., small acreage crops). • Lack ofreported usage data for the pesticide on a crop does not imply zero usage.

3• Usage data on a particular site may be noted in data sources, butnot quantified. In these instances, the site would notbe reported inthe SLUA. • Non-agricultural use sites (e.g., turf, post-harvest, mosquito control, etc.) are not reported inthe SLUA. Some sites showuse, eventhough they are not onthe label. This usage could be due to various factors, including, butnot limited to data collection orreporting errors, or application errors. Table 1. Screening-LevelEstimates ofAgricultural Uses ofAtrazine (2003-2010) (SLUA, dated 11115/2011) Crop Lbs. A.I.



## - 1 Com 60,000,000 2 Barley+ 7,000 3 Fallow 350,000 4 Pastureland 60,000 5 Pecans + 1,000 6 Potatoes+
. 11,000 7 Sorghum 5,600,000 

### 8 Soybeans
. 500,000 9 Sugarcane 2,000,000 10 Sunflowers + 6,000 11 Sweet.com 400,000**~** 12 Wheat 100,000 All numbers rounded. <2.5 Less than 2.5 percent ofcrop treated

<1 Less than 1percent ofcrop treated Percent Crop Treated (pCT)**"~** Avg. Max.

, 60 t, 70 <1**~** <2.5 <2.5 5 ," <1 <2.5
,
. <1 <2.5 <2.5 <2.5

65**~** 70 <1 <2.5 65 75 <1 , <2.5**,~** - 70 75**<1** <2.5

+ Crops notknown to be listed on active end use product registrations when this report was run. Typical Use Patterns (2006-2010) Forthe more recent timeframe of2006-2010, usage averaged approximately 66 millionpounds a.i. for 67 million acres. Atrazine is
. typically applied at a rate of0.3-2.3 pounds active ingredientper acre (lbs ail A) depending onthe crop as shown in Table 2. (Proprietary Data, 2006-2010). In additionto the average applicationrate data, a rate distribution was generated to calculate an upperboundrate for each crop. The upperbound rate inthis analysis is defined as the rate at which 90% (or as close to 90% as possible) ofthe acres treated with atrazine were treated at, or belowthatrate, as shown in Table 2.

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### TABLE 2. Typical Use Patterns for AtrazineUsed on Selected Crops (2006-2010) Crop Average Application Average number of Upperbound rate* (lbs Rate (lbs ail A) Applications Per ailA) percentile in 

### Year parenthesis Com 1.0 1.2 1.60 (89%); 1.75 (92%) Sorghum (Milo) 1.0 1.2 1.5 (85%); 1.60 (90%); 1.75 (93%) Sugarcane 2.3 1.4 3.75 (82%); 4.0 (100%)

Fallow 0.9 1.1 1.25 (79%); 1.45 (85%); 1.5 (95%) Sweet Com 0.8 1.1 1.5 (91%) Wheat, Spring 0.3 1.0 0.25 (67%); 0.45 (68%); (stubble) 0.5 (100%) Wheat, Winter 0.7 1.0 0.75 (83%); 0.90 (91%); (stubble) 1 (100%) Source: Propnetary Data, 2006-2010 *The upper boundrate (90th percentile) is defmed as the rate at which 90% (or as close to 90% as possible) ofthe acres treated with atrazine weretreated at orbelowthatrate. For example, in the above table, for sugarcane, 82 percent ofthe acres are treated at 3.75 lbs aj.lA or less, while the remaining 18 percent are all treated at4.0 lbs aj.lA. Top Crops and States with Highest Use (2006-2010) For2006-2010, the top crop interms ofaverage annual pounds ofactive ingredient applied was com (88%), followed by sorghum (8%), and sugarcane (2%) and sweet com and fallow (1% each). Spring and winter wheat stubble accounted for less than one percent oftotal pounds a.i. used during this period. As showninFigure 2, between 2006-2010, the states with the most agricultural usage interms of pounds a.i. applied were Illinois (17%), Iowa (11 

### %), Nebraska (10%), Indiana and Kansas (9% each), followed by Missouri, Ohio, Texas, and Kentucky with less than 5% each. The "other" category includes 29 other states with Minnesota, Michigan and Wisconsin having the most usage among those states.



### 5

### ,..-..-----------~---->----------__A.f lied) 2006-2010

KENTUCKY 2%

6% Source: Proprietary Data, 2006-2010 National Mapping Data Another measure ofusage is the use intensity. In this analysis, the use intensityis expressed as the pounds a.i. applied per acre ofland in fanns. This differs from the application rate, which is expressed as the pounds a.i. applied pertreated acre. Figure 3 is a map ofagricultural pesticide usage atthe Crop Reporting District (CRD) level that spatially represents atrazine use intensity inthe US. As shown, areas such as Florida and the comproducing states (colored inred) have the highest use intensity. CRDs are boundaries created by USDANASS which are aggregates ofcounties (USDA, 2010). Pesticide usage is displayed as average pounds (for the years 2006-2010) per 1,000 acres of fannland in a CRD to normalize for the variation infannland between CRDs. Fannland acreage was obtained from USDA (2007). Usage is based onprivate market surveys ofpesticide use in agriculture (Proprietary Data, 2006- 2010). The survey data are limited to the states thatrepresent the top 80-90 percent ofacreage for the individual crops, therefore, use may be occurring in regions outside the scope ofthe survey. CRDs showing no usage ofpesticides may be due to eitherthe lack ofpesticide use in the region or non-participation inthe agricultural surveys. In addition, across the years, there may be variations inthe specific crops included inthe CRD survey. This mayresult in a lower 

### annual average for the CRD.



### 6Figure 3. Atrazine Usage by Crop Reporting District (2006-2010)

Average Pounds per 1,000Acres of Farmland

. 0-8 9 - 49 

### 0 50

- 99 100 - 214

_ 215-580
Sources: Proprietary Data. 2006-2010 USDA, 2006-2010. NASS Crop Reporting Districts. USDA, 2007. Census ofAgriculture. NON-AGRICULTURAL USAGE N 

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Information onnon-agricultural usage in this section ofthe document has been obtained from available private market survey data from Kline 

### & Co. The information provided on atrazine use in this section is for select non-agricultural use sites and does notrepresent all non-agricultural usage (this is due to data limitations since datawas not available for all non-agricultural use sites). Non-agricultural usage data for professional applications to turfand ornamentals is available for 2002,2004 and 2006 (Table 3). Overthis time period, there was a notable increase in use by lawn care operators and on golfcourses, institutional turf, and turffarms (Kline & Co., 2002, 2004, 2006).



### 7Table 3
. Atrazine Select**Non-A~ricultural Usa~e**  (pounds A.I.) (2002,2 Site 2002 2004 GolfCourses N/A 3,085 Institutional Turf 3,493 11,479 Landscape 593 41,978 Lawn Care Operators 211,561 97,095 TurfFarms 145,013 269,829 Nursery/Greenhouse N/A 7,029 TOTAL Reported.(lbs. a.i.) 360,660 430,495 N/A= no atrazine use was reported inthe 2002 reports Source: Kline & Co., 2002, 2004, and 2006 2006 6,431 152,079

204 686,107 302,636

7,824 1,155,281 004,2006)

Forthe consumer market, approximately 400,000 pounds a.i. was applied in 2005 as lawn herbicide. Use was reported inthe earlier consumerreports (2001 and 2003); however, the use was not quantified because 

### itwas belowthe reporting threshold. REFERENCES Proprietary Data, 2000-2010 Kline & Co., Inc. 2001-2006 USDA, 2006-2010. NASS Crop Reporting Districts. Online: http://www.ers.usda.govibriefing/arms/resourceregions/resourceregions.htm#nass
. USDA, 2007. Census ofAgriculture. Online: http://www.agcensus.usda.govlPublications/2007 /index.asp US EPA, 2006, Atrazine Reregistration Eligibility Decision Document

cc: Melanie Biscoe

8Appendix. Atrazine Uses and Application Information Report The aggregated report includes label use and application information for atrazine. This information whichis based onthe LUIS generated EFED Table 1Aggregated Report (submitted to EFED in electronic format in a separate transmission) includes informationformatted to EFED's specification onuse site, application equipmenttype, application methodtype, application timing, and formulation description. Additional information from the label, where available, is also included inthe report, including maximum single applicationrates, maximum number ofapplications per crop cycle (CC) or year, minimumretreatment intervals, information on geographic use restrictions, and sample label registration numbers for eachuse site. As presented inthe Appendix, perthe label data, for comuse, applications canbe made up to a maximum single applicationrate of2.1 lbs aj.l A; for sorghum up to 2 lbs aj.l A; for sugarcane up to 4lbs aj.lA; for wheat (stubble) up to 2.21bs aj.lA, and for agricultural fallow and conservationreserve uses up to a rate of2.2 lbs aj.l A. Additionally, applications canbe made up to at a maximum single applicationrate of2lbs aj.lAfor Christmas tree plantations; for forest trees up to 4lbs aj.lA; for golfcourse turfup to 2lbs aj.lA; for ornamental lawns and turf up to 2.7 lbs aj.l A; for ornamental sod farms up to 4 lbs a.i.I A; and for residential lawns up to a single maximum applicationrate of2.7 lbs aj.l A.

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