UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

DEC 16 2014 

OFFICE OF CHEMICAL SAFETY 

AND POLLUTION PREVENTION 

:MEMORANDUM 

SUBJECT: 

FROM: 

THRU: 

TO: 

/J ,C\ . . . - ( 

Science 

Cynthia 

Information 

Doucoure, Environmental Protection 

and Analysis Branch 

Specialist t: ~ 

Economic 

Monisha Kaul, 

Analysis 

Environmental 

Branch 

Protection Specialist (J1 ~ ~ ~ 

Biological and Economic Analysis Division (7503P) 

Biological 

Arnet Jones, 

Analysis 

Chief 

Br<ll!-ch ~U 

/) A() J ~ 

Diann Sims, Chief ,:_Ut~~-'"'---1 Science Information and Analysis Branch 

~ Timothy Kiely, Chief fj1;- 1/v\, l· 

Economic Analysis Branch '"J j 

Biological and Economic Analysis Division (7 P) 

Julia Stokes, Chemical Review Manager 

Risk Management and Implementation Branch V 

Pesticide Re-evaluation Division (7508P) 

Product Review Panel date: April16, 2014 

Page 1 of10 
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 ofthe team ofEPA staff currently evaluating the registration status 

of etoxazole, and eventually the general public. This document builds upon the data BEAD 

provides in the Label Use Information System (LUIS) reports and the Screening Level Usage 

Analysis (SLUA) to Registration Review teams. The document is based on information and 

data available to BEAD as of January 2014. 

Etoxazole was conditionally registered in August 2002 as a miticide/ovicide. The Insecticide 

Resistance Action Committee (IRAC), a group of industry technical experts, classifies etoxazole 

in Group 1 OB, with a mode of action that is described as ''mite growth inhibition". Hollingworth 

and Treacy (2006) describe etoxazole's activity on mites as follows:" ... primarily active against 

tetranychid mites in the egg and larval stages, but it has no effect on adults and is rather slow 

acting. It has translaminar but no systemic activity. The half-life for dissipation in the field is a 

few days to a few weeks". 

HISTORY OF BEAD ASSESSMENTS FOR ETOXAZOLE 

ln 2011, BEAD conducted a review ofthe registrant's request to extend exclusive use of 

registration data. In that assessment, BEAD concluded that etoxazole met benefits-related 

criterion IV for a three year extension of exclusive use of data by the registrant, in that it played a 

useful role in managing mites as part of an integrated pest management (lPM) program for nine 

minor crops included in the registrant's exclusive use request (pear, cherries, plums, peaches, 

strawberry, hops, walnuts, mint, and muskmelons). In addition, BEAD concluded that etoxazole 

met the requirement for Criterion III (compelling evidence that etoxazole can be used to manage 

resistance to acaricides with different Modes of Action) for muskmelon, because this crop did 

not have the very similar acaricides clofentezine and hexythiazox registered (Mallampalli, 2011 ). 

COMMON FORMULATIONS AND APPLICATION METHODS 

Etoxazole is commonly formulated as water dispersible granules, emulsifiable concentrates, and 

wettable powders. It is applied aerially or by ground applications using compressed air sprays, 

hydraulic sprayers, or ground boom sprayers. 

USE SITES 

Agricultural Use Sites: 

Etoxazole is registered for use on the 8-1 OB Pepper/Eggplant subgroup, Cucurbit Crop Group 9, 

Pome Fruit Group 1 1, 13-07 A Caneberry subgroup, 13-07F Small fruit vine climbing subgroup, 

except fuzzy kiwifruit, and 13-070 Low growing berry subgroup. Etoxazole is also used on 

Page 2 of 10 
alfalfa grown for seed, carrots grown for seed, com grown for seed (field and popcorn), cotton, 

non-bearing fruit trees, hops, mint, stone fruits, subtropical/tropical fruit, tomato, tree nuts and 

Christmas tree plantings. 

Non-Agricultural Use Sites: 

Etoxazole is registered for use on ornamentals and in greenhouses. 

ETOXAZOLE USAGE 

·BEAD prepared a Screening Level Usage Analysis (SLUA) in May 2013 that provided data on 

use of etoxazole on nuts (almond and walnuts), pome fruit, stone fruit, grapes, melons, 

strawberries, and cotton in the U.S. during the 2004-2011 timeframe. The crops with the highest 

average percent crop treated include strawberries (15%) and pears (10%). The crops with the 

highest average pounds a.i. applied include almonds (6,000 lbs a.i.), grapes (5,000 lbs a.i.), and 

cotton (2,000 lbs a.i.). 

Agricultural Usage Trend 

According to proprietary market research surveys, reported use of etoxazole in the U.S., in terms 

of pounds a.i. applied and total area treated, has continued to increase following a sharp decrease 

in use in the middle of the period shown in Figures 1 and 2. The overall average a.i. rate of 

application during this period was 0.09 lbs a.i. per acre. 

Figure 1. Etoxazole Usage: Pounds AI Applied, 2004-2012 

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40,000 l 

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0 

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2004 2005 2006 2007 2008 

Year 

Page 3 of 10 

2009 2010 2011 2012 
Figure 2: Etoxazole Usage: Total Area Treated Applied, 2004-2012 

400,000 

0 

2004 lOOS 2006 2007 2008 2009 2010 2011 2012 

Year 

Source: EPA Proprietary Data, 2004-2012 

Agricultural Usage Trend: Top Crops. 2008-2012 

Following a sharp decline in at the beginning of the period, reported use of etoxazole increased 

steadily during the remainder of the 2008-2012 time frame. The crops with the highest 

proportion oftotal pounds a.i. applied were almonds (37%), wine grapes (19%) and cotton (13,, 

followed by table grapes (8%), strawberries (7%), and pears (6%), as shown in Table 1. The 

average annual pounds a.i. applied during this period was 23,000 and the overall average a.i. 

application rate was 0.09 lbs a.i. per acre. Etoxazole was applied at higher than overall average 

application rates on all crops except cotton and table grapes. 

Page 4 oflO 
T bl I E a e toxazo Ie U se on T C ~ rops, 2008 -2012 

2008-lOll 

Average= 23,128 lbs/yr 

Crop %of Total Lbs A.l. %of Total Area A vg. A. I. Rate of 

Applied Treated Application (lb a.i./acre) 

Almonds 37 31 0.11 

Wine Grapes 19 14 0.13 

Cotton 13 29 0.04 

Table Grapes 8 9 0.08 

Strawberries 7 5 0.13 

Pears 6 4 0.12 

Other* 10 8 0.09-0.14 

*Other crops include apples. apricots, cantaloupes, cherries, com, raisin grapes, peaches, walnuts, and 

watermelons. Source: Propnetary Data, 2008-20 12 

Agricultural Usage Trend: Top States. 2008-201 2 

The state.s with the highest proportion of pounds a.i. applied during the 2008-2012 timeframe 

were California (80%), Louisiana (5%) and Washington (5%). Etoxazole was applied at higher 

than overall average application rates in all states except Louisiana. 

T a bl e 2 E toxazo I e U se tn . T op S tates, 2008 -2012 

2008-lOU 

Average= 23,000 lbs/yr 

State %of Total Lbs A.l. %of Total Area Treated Avg. A.l. Rate of 

Applied Application Ob a.i./acre) 

California 80 69 0.10 

Louisiana 5 10 0.04 

Washington 5 4 0.12 

Other* 10 17 0.03-0.14 

•Other states include AZ, AR, FL, Ml, MS, MO, NY, NC, OH, OR, PA, TN, TX, VA, and WV 

Source: Proprietary Data, 2008-2012 

Agricultural Use lntensitv ofEtoxazole Use in the U.S. 

Another measure of usage is the use intensity. In this analysis, the use intensity is expressed as 

the average annual amount (in pounds) of the active ingredient applied per 1,000 acres of crop 

acres grown. This differs from the application rate, which is expressed as the pounds a.i. applied 

per treated area Figure 3 spatially represents etoxazole's use intensity in California on several 

crops including almonds and wine grapes. For more information about this map, see Appendix 

A. 

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Figure 3. Annual Average Agricultural Use Intensity of Etoxazole (2008-2012). 

POWMis Active Ingredient 

per 1.000 Crop Acres Grown 

c:JNoOIII 

o 11 

011·023 

- 02•·032 

- >032 

(Source: Proprietary Data,l008-l01l) 

Non-Agricultural Usage 

BEAD reviewed available data sources and found two years of reported use of etoxazole in 

nursery and floriculture as shown in Table 3 below. While national-level use in nursery and 

floriculture is relatively low (Table 3), use in California on ornamentals (in terms of area treated) 

appears quite high, based on CDPR data (Table 4). · 

T a bl e 3 E I U . N toxazo e sem ursery &FI oncu . I ture 

Year Total Lbs A.I. Avg. A.l. Rate of 

Applied Application (lb a.i./acre) 

2006 800 0.06 

2009 200 0.04 

Source: USDA NASS Agncultural Chemtcal Usage Reports, 2006 and 2009 

Page 6 of10 
Table 4. Etoxazole Use in California on Ornamental Plants, 2010-2012 

Commodity 2010 2011 

Lbs Area Lbs Area 

A. I. Treated A. I. Treated 

Applied (Acres) Applied (Acres) 

Greenhouse Flowers & 34 76 32 13 

Plants in Containers 

Outdoor Flowers & 33 6 14 11 

Plants in Containers 

Total 67 82 46 139 .. Source: Cahfom1a DPR, Annual Statewide Pest1c1de Use Reports, 2010-2012 

BIOLOGICAL ASPECTS RELEVANT TO ETOXAWLE 

Lbs 

A. I. 

Applied 

67 

140 

207 

2012 

• 

. .. 

Area 

Treated 

(Acres) 

125 ' 

35 

160 

The publicly accessible database of published scientific literature on arthropod resistance that is 

maintained by Michigan State University (available at 

http://www.pesticideresistance.com/index.php) lists only one publication documenting resistance 

to etoxazole. This item reports reduced susceptibility to etoxazole in two-spotted spider mites in 

Korea (KiSu et al. 2004). However, other studies have provided some evidence that resistance to 

clofentezine can lead to cross-resistance to etoxazole in European red mite (Pree et al. 2005), and 

that resistance to hexythiazox and etoxazole are genetically linked in spider mites (Asahara et al. 

2008). Both clofentezine and hexythiazox are classified in the Mode of Action Group 1 OA, and 

are mite growth inhibitors similar to etoxazole. The extent of such cross-resistance in U.S. crops 

is not clear to BEAD. Pree et al. (2005) obtained their results using laboratory colonies 

established from mites collected in Canadian apples and peaches; Asahara et al. (2008) used 

spider mites collected in Japan. 

As mentioned earlier in this document, for at least some minor crops etoxazole appears to be a 

useful component in IPM programs, largely because its efficacy appears to ·be very mite-specific, 

and thus has lower toxicity to some non-mite beneficial insects than alternatives such as some 

synthetic pyrethroids, propargite, dicofol, and pyridaben. For example, Ashley et al. (2006) 

found that etoxazole did not affect minute pirate bugs as much as either fenpropathrin or 

propargite. Pirate bugs are common predators ofthe eggs and larvae of many agricultural pests, 

including mites and aphids. 

ROLE OF ETOXAZOLE IN PEST MANAGEMENT 

Based on the available usage data, etoxazole appears to play an important role in the production 

of major crops in California, including strawberries, pears, almonds, and wine grapes. The 

available data also shows considerable use of etoxazole in California on greenhouse, 

containerized, and outdoor plants and flowers (Table 4). Etoxazole appears to be an effective 

mite growth inhibitor and has lower toxicity to some non-mite beneficial insects such as the 

Page 7 of 10 
\ 

\ 

pirate bugs, which are predators of agricultural pests. It is also a useful component in IPM 

programs. 

BEAD is unsure why there is greater use of etoxazole in California ornamental production as 

compared to national-level data. Quinn et al. (2009) mention etoxazole and hexythiazox ( a very 

similar insecticide) among several options useful in nursery and greenhouse IPM programs that 

target spider mites. However. hexythiazox is limited to one application in California production 

of these crops, while etoxazole can be applied up to two times per season. This may be a factor 

in its greater use. Other factors. such as lower product cost, product availability, or localized 

resistance, may be driving factors as well. 

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

ETOXAZOLE 

Obtaining the following usage information may improve future assessments conducted by the 

Agency related to the use and importance of etoxazole: 

1) Typical application timing in each registered crop. 

2) Details on the pest management importance of etoxazole in California ornamental 

production. 

3) If more than one application is typically made, the typical re-application interval (per 

crop). 

4) Recent resistance reports for etoxazole in populations of important target pests, in 

particular cases of cross-resistaJ?-Ce to both hexythiazox, clofentezine, and etoxazole. 

REFERENCES 

Asahara, M., R. Uesugi, and M.H. Osakabe. 2008. Linkage between one of the polygenic 

hexythiazox resistance genes and an etoxazole resistance gene in the two spotted spider 

mite (Acari: Tetranychidae). J. Econ. Entomol. 101(5): 1704-1710. 

Ashley, J.A .• D.A. Herbert, E.E. Lewis, C.C. Brewster, and R. Huckaba. 2006. Toxicity of three 

acaricides to Tetranychus urticae (Tetranychidae: Acari) and Orius insidiosus 

(Anthocoridae: Hemiptera). J. Econ. Entomol. 99(1): 54-59. 

EPA Proprietary Data, 2004-2012 

EPA, Etoxazole Screening Level Usage Analysis (SLUA), May 2013 

Hollingworth, R. M. and M.F. Treacy. 2006. Classification and Properties of Commercial 

Insecticides and Acaricdes. Pp 36-67 In: Use and Management of Insecticides. Acaricdes, 

and Transgenic Crops. J.N. All and M.F. Treacy (eds). Joint publication of the 

Entomology Society of America and the American Phytopathological Society. 

Page 8 oflO 
KiSu, A., K. Gilhah, L. Soyoung, K. Chulsu, and S. Sangchul. 2004. Inheritance and stability of 

etoxazole resistance in two-spotted spider mite, Tetranychus urticae, and its crossresistance. Korean J. Appl. Entomol. 43: 43-48. 

Mallampalli, N. 2011. Review of a Request for Extension of the Exclusive Use Period for 

Etoxazole (DP # 384053). BEAD Official Record. 

Pree, D.J., K.J. Whitty, and L. Van Oriel. 2005. Baseline susceptibility and cross resistances of 

some new acaricides in the European red mite, Panonychus ulmi. Experimental and 

Applied Acarology (2005) 37: 165-171. 

Quinn, J., D. Trinklein, and R.A. Cloyd. 2009. Integrated Pest Management in Greenhouses and 

Herbaceous Nurseries. Publication IPM0126 from the University of Missouri Extension 

Service. Available on the web at http://extension.missouri.edu/p/IPM1026. [Accessed 

April 2014]. 

USDA NASS Agricultural Chemical Usage Reports, 2006 and 2009. 

Page 9 oflO 
APPENDIX A 

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 I ,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 (l ,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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