UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

IJUL 06 2011 

MEMORANDUM 

OFFICE OF CHEMICAL SAFETY 

AND POLLUTION PREVENTION 

SUBJECT: BEAD Chemical Profile for Registration Review: Thiamethoxam (060109) 

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FROM: David 

Biological 

Brassard, 

Analysis 

Senior 

Branch 

Entomologist ~~ ~ 

JihadAlsadek,Economist 7~ It. 11-~ Science Information and Analysis Branch 

Derek Berwald, Economist V /r1.. \M.. ~~ Economic Analysis Branch "" \) 

Biological and Economic Analysis Division (7503P 

THRU: Arnet Jones, Chief J ..... 1I!3-t-- 4- A .. ~ -:1;--s 

Biological Analysis Brarih- /' 

Diann 

Science 

Sims, 

Information 

Chief ~ and Analysis Branch 

Timothy Kiely, Chief (\... \,\.VI rQ 

Economic Analysis Branch ~, J. U 

Biological and Economic Analysis Division (7503P) 

TO: Carissa Cyran, Chemical Review Manager 

Risk Management and Implementation Branch 1 

Pesticide Re-evaluation Division (7508P) 

Product Review Panel date: June 15,2011 

INTRODUCTION 

The purpose of this document is to convey usage information and a broad overview of the pest 

management roles of pesticides that are beginning to undergo registration review. The 

anticipated audience consists of the team of EPA staff currently evaluating the registration status 

of Thiamethoxam, and eventually the general public. This document builds upon the data already 

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provided in the "Usage and Label Use Data Packages" that are also provided to Registration 

Review teams by BEAD .. The document is based on information and data available to BEAD as 

of June 15,2011. 

Thiamethoxam is a second generation neonicotinoid insecticide, belonging to the thianicotinyl 

subclass. Thiamethoxam acts on the central nervous system by binding to the postsynaptic 

nicotinic acetylcholine receptor. Thiamethoxam is highly water soluble and is readily 

translocated in plant tissue giving it good systemic activity. Thiamethoxam has stomach and 

contact activity and is effective against a wide variety of insects ~cluding aphids, thrips, beetles, 

centipedes, millipedes, sawflies, leaf miners, stem borers and termites. 

USE SITES 

Agricultural Use Sites 

Thiamethoxam is registered for use on a wide variety offield, fiber, forage, fruit, spice, and 

vegetable crops. The following is a partial list of registered crop uses: 8J.falfa, apple, artichoke, 

broccoli, cabbage, caneberries, cantaloupe, carrot, cauliflower, celery, cherries, com, cotton, 

cucumbers, dry beans, grapefruit, grapes, lemons, lettuce, oranges, peaches, peas, pears, pecans, 

peppers, plums/prunes, potatoes, pumpkins, sorghum, soybeans, spinach, squash, strawberries, 

sunflower, sugarbeet, tobacco, tomatoes, watermelons, and wheat. 

Non-Agricultural Use Sites 

Thiamethoxam is registered for use on or in domestic dwellings, food handling establishments, 

commercial/institutional/industrial areas, livestock pens, poultry houses, wood or wooden 

structures, and transportation vehicles. 

COMMON FORMULATIONS AND APPLICATION METHODS 

Thiamethoxam is marketed in the following formulations: granular, water dispersible granules, 

emulsifiable concentrate, flowable concentrate, soluble concentrate, and ready-to-use solution. 

Thiamethoxam is applied as a foliar treatment, soil treatment, seed treatment, water treatment, 

bait application, and premise treatment. 

USAGE 

Agricultural 

Based on private market pesticide usage data from 2000-2010, the annual total agricultural usage 

averaged 400,000 pounds active ingredient for 18 million treated acres for an overall average 

application rate of 0.02Ibs. a.i. per acre. The annual total agricultural usage data for the last 

three years, 2008-2010, averaged 900,000 pounds active ingredient for 45 million treated acres 

for an overall average application rate also of 0.02 lbs. a.i. per acre. In comparison to this rate, 

the average a.i. application rate in lbs. a.i. per acre is 0.03 for both soybeans and cotton and 0.01 

for com. The use of thiamethoxam has been increasing over time. 

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From 2000-2010, the crops with the highest use in terms of total pounds of active ingredient 

applied are soybeans (36%), com (31 %), and cotton (26%). Crops with the highest total area 

treated (TAT) are com (51 %), soybeans (27%), and cotton (16%). 

On average, the states with the highest use ofthiamethoxam in terms of pounds a.i. applied are 

Iowa (10%), Nebraska (7%), and Texas, Arkansas, Mississippi, Minnesota, and Illinois (6% 

each). 

(proprietary Data, 2000-2010). 

Non-Agricultural 

About 300 lbs. a.i. ofthiamethoxam was used in greenhouses and nurseries in 2006. 

USE TRENDS 

Figure 1 provides usage data for crops with the highest use of thiamethoxam in terms of pounds 

a.i. applied for the whole period, 2000-2010. The use of thiamethoxam on com started in 2004 

and was increasing thereafter. The use on soybeans increased from 2006 to 2010. The use of 

thiamethoxam fluctuated on cotton (2000-2010). The crops in "other crops" with the most use of 

thiamethoxam are potatoes (3%), spring wheat, winter wheat, and sorghum (1 % each). Figure 2 

provides usage data for crops with the highest use of thiamethoxam in terms of pounds a.i. 

applied for the last three years (2008-2010). Data for these three years show the use of 

thiamethoxam is rising on cotton, soybeans, and "other crops", while the use ofthiamethoxam on 

cotton is almost stable. The use of this chemical has increased over time. The data provided in 

this section are provided for preliminary scoping purposes only because the data have not been 

analyzed. 

Figure 1 ThiamethoxamAgricultural Use, 2000-2010 

1,200,000 -r-----------------

• Other Crops 

PoundsA.I. 

• Soybeans 

• Cotton 

. Corn 

20002001200220032004200520062007200820092010 

Years 

"Other crops" with significant usage ofthiamethoxam includes potatoes (3%), spring wheat, 

winter wheat, and sorghum (1 % each). 

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Figure 2 Thiamethoxam Agricultural Use, 2008-2010 

1,200,000 

PoundsA.I. 

o 

2008 2009 Years 

• Other Crops 

• Soybeans 

• Cotton 

. Corn 

2010 

"Other crops" with significant usage ofthiamethoxam includes potatoes (3%), spring wheat, 

winter wheat, and sorghum (1 % each). 

Source: Proprietary Data, 2000-2010 

BIOLOGICAL ASPECTS RELEVANT TO THIAMETHOXAM 

The registrant makes a number of plant health claims regarding thi.amethoxam (Syngenta 2011). 

Syngenta's trademarked name for this phenomenon is "Thiamethoxam VigorTM." Syngenta 

claims that thiamethoxam offers growers additional benefits beyond broad-spectrum insect 

protection such as faster emergence, greater plant stands, earlier canopy, taller and greener 

plants, and improved qUality. Syngenta claims thiamethoxam positively affects the plant through 

its ability to increase the biosynthesis of functional proteins resulting in more effective defense 

against numerous environmental stress conditions (Syngenta 2011). 

mSTORY OF BEAD ASSESSMENTS FOR THIAMETHOXAM 

Thiamethoxam has been evaluated for Section 18 requests several times, but only once in the last 

five years. In that case, there was a request for thiamethoxam to control grape colapsis in 

Arkansas rice. The state, however, provided insufficient yield loss infonnation for BEAD to 

detennine if there would be a significant economic loss without thiamethoxam. In earlier 

requests, an urgent and non-routine situation was found for requests to control cranberry weevil 

in Massachusetts (2003, 2002). BEAD was unable to make a finding or found the situation to be 

either non-urgent or routine for pears, in Washington, soybean for seed in Iowa, insect pests in 

South Carolina peaches and dry beans for seed in Washington and Idaho. 

INFORMATION THAT MAY BE USEFUL FOR BEAD'S FUTURE WORK ON 

THIAMETHOXAM 

Obtaining additional infonnation on the following items would improve future BEAD 

assessments of the importance of thiamethoxam and may be required as part of the registration 

review of this pesticide. 

BEAD would like to obtain additional usage infonnation on the non-agricultural use sites. Our 

available non-agricultural database does not survey these sites. 

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REFERENCES 

Proprietary Data~ 2000-2010 

Kline and Company, Inc., 2006 

Label Use Information System (LUIS) Report, 2011 

Syngenta. 2011. Thiamethoxam Questions and Answers. 

http://www.syngentacropprotection.com/assets/assetli brary/ canada THX OA. pdf 

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