UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

OCT 3 0 2014 

MEMORANDUM 

OFFICE OF CHEMICAL SAFETY 

AND POLLUTION PREVENTION 

SUBJECT: BEAD Chemical Profile (BCP) for Registration Review: Spiromesifen (PC Code: 

024875) 

FROM: Nikhil Mallampalli, Ph.D., Entomologist /It L lJ. M~ Biological Analysis Branch 

THRU: 

Don 

Science 

Atwood, 

Information 

Ph.D., 

and 

Entomologist 

Analysis Branch 

~ owzt.ft' Jr1; ~ 

Diann Sims, Chief 

Science Informatio an Analysis Branch .. 

Timothy Kiely, Chief (,\__ \f'J\._ (~ Economic Analysis Branch '-.J J 

Biological and Economic Analysis Division ( 03P) 

TO: Julia Stokes, Chemical Review Manager 

Pesticide Re-evaluation Division (7508P) 

Peer Review Panel date: October 15, 2014 

Page 1 of 10 
SUMMARY 

Spiromesifen is a miticide/insecticide currently undergoing registration review. Since it was first 

registered in 2005, it has not undergone such a review in the past. This pesticide is active against 

many species of phytophagous mites, as well as some whitefly and Psyllid species that are 

serious plant pests. It acts by interfering with growth regulation and lipid biosynthesis. It is 

currently registered as a "reduced-risk" pesticide for use in a variety of crops, including com, 

cotton, vegetables, berries, and leafy greens. It is also registered on ornamentals. National level 

use of spiromesifen has increased significantly between 2005 and 2012. The reasons for the 

increase are not fully clear but probably include factors such as increased pest resistance to other 

miticides and growers' need to simultaneously control multiple pests such as psyllids, whiteflies 

and mites. Crops that show major uses of spiromesifen are com, potatoes, and strawberries, all of 

which have various significant mite pests in most growing regions. Details of usage, the 

chemical's role in pest management, and current BEAD data needs relevant to registration 

review are presented below. 

INTRODUCTION 

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

overview of the pest management roles and quantitative usage information for spiromesifen. The 

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

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

information on use is available in the Spiromesifen Label Data Report provided in the public 

docket for this chemical. Information provided in this document may be used by stakeholders 

(e.g., users and registrants), OPP risk assessors, and OPP risk managers, and the general public 

during the Registration Review process of this pesticide. 

AGRICULTURAL USE SITES 

Spiromesifen is registered for use on low growing berries (subgroup 13-07G), tuberous and corm 

vegetables (subgroup 1 C), leafy greens (subgroup 4A), fruiting vegetables, brassica vegetables 

(subgroup SA), celery, com, cotton, and cucurbits. 

NON-AGRICULTURAL USE SITES 

Spiromesifen is labeled for use on one non-agricultural use site: ornamentals. 

FORMULATIONS AND APPLICATION METHODS 

Spiromesifen is formulated as a suspension concentrate and emulsifiable concentrate. 

Application may be made using either ground or aerial equipment. 

Page 2 of10 
IDSTORY OF SPIROMESIFEN AND BEAD PRODUCTS 

Spiromesifen was first registered by the U.S. EPA in 2005. Since then, EPA has approved two 

Section 18 emergency exemption requests for use of spiromesifen to control spider mites on 

soybeans in Delaware, one in 2008 and one in 2009. BEAD reviewed the first of these two 

requests and determined that there was an emergency situation due to drought conditions which 

had caused spider mite populations to increase (Chiri and Lee, 2008). In 2014, BEAD prepared 

a screening level usage analysis (SLUA) which showed that, over a period of eight years, the 

crops with the highest percent crop treated (Pen were strawberries (55%), eggplant (45%), and 

cantaloupes (30%) (Table 2). BEAD has not conducted any other assessments for this chemical. 

SPIROMESIFEN USAGE 

Agricultural Usage 

Usage of spiromesifen in terms of pounds applied and number of acres treated both showed a 

steady increase from 2005 to 2012 (Figure 1 ). Usage of spiromesifen was noted to decrease in 

terms of acres treated and pounds applied between 2011 and 2012. However, this mostly likely 

only reflects yearly variation in usage as has previously been observed between 2006 and 2007 

and between 2009 and 2010. Overall, there is still a positive usage trend for spiromesifen. 

900,000 

0 

...,._Total Area Treated 

- .. - Pounds AI 

2005 2006 2007 2008 2009 2010 2011 2012 

Year 

130,000 

0 

"CI 

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a. 

Cl. 

< 

:cc 

VI 

"CI 

c 

::I 

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f:l. 

Figure 1. National Spiromesifen Usage (Lbs A.I. and Total Area Treated), 2005-2012 

Source: Proprietary Data, 2005-2012 

A review of total spiromesifen usage data for the last 5 years indicates that the major use sites are 

corn, potatoes, and strawberries, accounting for 86% of total usage relative to pounds applied 

and 85% of acres treated (Table 1 ). 

Page 3 of 10 
T a e bl 1 . C rops w1 'th H' 121 h t es U se o f S ,p1romes1 . 'fi en, 2008 -2012 

Crop Average %of Total Average Total %of Total 

LbsAI Spiromesifen Acres Spiromesifen 

Lbs Applied Treated* Treated Acres 

Com 43,100 57% 365,800 65% 

Potatoes 13,600 18% 70,700 13% 

Strawberries 8,600 11% 34,900 6% 

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

Source: Proprietary Data, 2008-2012 

While com, potatoes, and strawberries have the highest percentage of lbs applied and total acres 

treated, the crop with the highest percent crop treated is eggplant at 45% (Table 2). This 

indicates that spiromesifen plays an important role in pest control for some crops with relative 

low total pounds applied. 

Table 2. Percent Crop Treated with Spiromesifen for crops with most usage and crops 

WI 'th grea t er th an 5 percen t t t d crop rea e , 2004 -2012 

Crop Percent Crop Treated 

Avg. Lbs. A.I.* Average Maximum 

Com 30,000 <1 <2.5 

Potatoes 10,000 5 10 

Strawberries 6,000 35 55 

Peppers 2,000 10 25 

Sweet com 2,000 5 10 

Cantaloupes 1,000 10 30 

Watermelons 1,000 5 10 

Cucumbers <500 10 20 

Eggplant <500 45 45 

*Lbs A.I. may differ from Table 1 as Percent Crop Treated estimates encompass an extended 

time frame, 2004-2012 

Source: Spiromesifen SLUA (EPA, 2014) 

Table 3 indicates states with highest usage ofspiromesifen in terms of percent oftotal 

spiromesifen lbs a.i. applied and percent of total acres treated with spiromesifen. Texas is the 

state with highest usage in terms of both total pounds of spiromesifen applied and total acres 

treated with it. California is close to Texas in terms of percent of total spiromesifen lbs applied 

but no state is close to Texas relative to the percent of total acres treated with spiromesifen. 

Page 4 of 10 
T a e bl 3 . St a t esw1 'th H" I~J h t es U se o f S ipiromesi . 'f, en, 2008 -2012 

State %of Total State % of Total Acres 

Spiromesifen Lbs Treated with 

Applied Spiromesifen* 

Texas 27 Texas 30 

California 22 California 18 

Washington 15 Kansas 11 

Kansas 9 Washington 12 

Colorado 8 Colorado 9 

New Mexico 8 New Mexico 9 

Idaho 5 Idaho 5 

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

·source: Proprietary Data, 2008-2012 

Application Rates and Methods 

Spiromesifen average application rates across all crops from 2008 to 2012 range from a low of 

0.094lbs a.i./acre for artichokes to a high of0.246lbs a.i./acre for strawberries. Average 

application rates for the major use sites based on average totallbs applied in the United States 

are provided in Table 4. 

T a e bl 4 . S ip1romes1 . ·r, en u se on T C op rops: A verage AIR .. a t e, 2008 -2012 

Crop Average Total Lbs Average Total Avg. A.I. Rate 

Acres Treated* (lbs a.i./acres) 

Corn 43,100 365,800 0.118 

Potatoes 13,600 70,700 0.193 

Strawberries 8,600 34,900 0.246 

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

Source: Proprietary Data, 2008-2012 

Table 5 provides average spiromesifen application rates by state. The highest application rate, 

0.174 lbs a.i./acre, is used in Washington and is primarily related to higher application rates in 

potato production. The lowest application rate is 0.105 lbs a.i./acre in Kansas on corn. 

Page 5 of 10 
Table 5. Spiromesifen Use in Top States: Average A.I. Rate, 2008-2012 

State Average Total Lbs Average Total 

Applied Acres Treated* 

Texas 20,000 168,400 

California 16,800 100,900 

Washington 11,100 63,600 

Kansas 6,900 65,700 

Colorado 6,100 50,500 

New Mexico 5,700 47,900 

Idaho 4,100 29,000 

Avg. A.I. Rate 

(lbs a.i./acres) 

0.119 

0.167 

0.174 

0.105 

0.121 

0.120 

0.141 

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

Source: Proprietary Data, 2008-2012 

According to proprietary data, ground applications account for 55% of spiromesifen lbs applied 

and 50% of total acres treated. Broadcast applications account for 98% of spiromesifen lbs 

applied and 97% of total acres treated. Custom application, not farmer, represents 69% of 

spiromesifen lbs applied and 73% of total acres treated. In the database, "custom application" 

refers to treatments made by professional pesticide applicators hired by the grower. 

Geographic Distribution of Spiromesifen Use 

Spiromesifen has wide usage in the United States (Figure 1 ). States with highest pounds per 

1,000 crop acres grown include New Mexico, California, and Washington (Figure 2). However, 

while New Mexico appears to have the greatest use intensity, this is largely an artifact of the low 

crop acres grown within the state. 

The high use intensity in California is associated with the high number of crop acres within the 

state and the use of spiromesifen on 14 crops within the state. In addition, the intensity in 

California is driven by use on two of the major spiromesifen crops, com and strawberries. The 

high use intensity in Washington results from use on potatoes, another of the major spiromesifen 

crops. Use intensity in Texas, Colorado, and Idaho are related to com production whereas use in 

Arizona is linked to cantaloupe and watermelon production. 

Page 6 of 10 
Figure 2. Annual average agricultural use intensity of spiromesifen (2008-2012). 

Pounds Active Ingredient 

per 1,000 Crop Acres Grown 

D No Data 

0 <0.1 

D o.1-o.4 

0.4-0.8 

. 0.8-2 

- >2 

More information about this map is available in Appendix A. 

Page 7 of 10 
Non-Agricultural Usage 

Non-agricultural usage of spiromesifen is minor in comparison to agricultural usage with less 

than 6.5 thousand pounds applied in 2012. Proprietary data indicates use on landscapes, lawns, 

and in nursery/greenhouses (Table 6). 

Table 6. Non-agricultural use of spiromesifen. 

Lbs A.I Applied 

Use Site (1,000) 

Landscape 0.07 

Lawn Care 

Nursery/Greenhouse 

Source: Proprietary data, 2012 

5.99 

0.33 

ROLE OF SPIROMESIFEN IN PEST MANAGEMENT 

Spiromesifen is categorized in Mode of Action group 23 by the Insecticide Resistance Action 

Committee (an industry group of technical experts). Other members of this group, spirodiclofen 

and spirotetramat, are also registered in the U.S. These pesticides are all toxic to target 

arthropods by interfering with growth regulation and lipid production. Both spiromesifen and 

spirotetramat have reduced-risk status, while spirodiclofen does not (EPA, 2013). Spiromesifen 

has contact toxicity mainly to mite eggs and immatures, as well as contact toxicity to psyllids 

and whiteflies (which also feed on plant phloem, as do mites). 

Thought it is not fully clear why there has been a general increase in spiromesifen usage in 

recent years, underlying factors may include increased pest resistance to other miticides and 

growers' need to simultaneously control multiple pests by using a broader spectrum chemical, 

relative to other popular ·miticides. Another factor may be the extended drought conditions 

experienced in Texas and California in at least the past two years. Hot and dry weather 

frequently fosters high populations of phytophagous mites, particularly the two-spotted spider 

mite, Tetranychus urticae, which is a pest on virtually all of the crops that spiromesifen is 

registered for. 

DATA NEEDS 

The Agency currently does not have important information on spiromesifen. Obtaining the 

following information on usage for any or all registered non-agricultural sites may improve 

future assessments conducted by the Agency related to the use and importance of spiromesifen: 

• Total pounds active ingredient applied 

• Percent crop/site treated 

• Application rates: typical and maximum 

• Frequency of application 

• Application Intervals 

Page 8 of 10 
• Efficacy information/product performance 

• Recent reports of pest resistance. 

REFERENCES 

Bynum E.D., G. J. Michels, Jr. and J. B. Bible. 2009. Evaluation of Banks Grass Mite and TwoSpotted Spider Mite Response to Spiromesifen Field Application and Potential Changes in 

Spiromesifen Tolerance: A report to the Texas Com Producers Board. Available on the web 

at: http:/ /amarillo. tamu.edu/files/20 13/04/2009-0beron-TCPB.pdf [Accessed Sept 2014]. 

EPA. 2014. Spiromesifen Screening Level Usage Analysis. Biological and Economic Analysis 

Division, Office of Pesticide Programs, U.S. Environmental Protection Agency. 

Chiri, A. and A. Lee. 2008. Review of Emergency Exemption Request for the Use of 

Spiromesifen for Control of Spider Mites on Soybeans in Delaware (08DE03) (DP #354193). 

Biological and Economic Analysis Division, Office of Pesticide Programs, U.S. 

Environmental Protection Agency. 

Proprietary Data. 2004-2012 

Proprietary Data. 2008-2012 

Proprietary Data. 20 12 

Page 9 of 10 
APPENDIX A 

The map included herein (Figure 2) 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 ail 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. · 

Page 10 of 10