UNITED STATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON, D

.C

. 20460 

## FEB 04 Z013

MEMORANDUM OFFICE OF CHEMICAL SAFETY AND POLLUTION PREVENTION

SUBJECT: BEAD Chemical Profile for Registration Review: Abamectin (122804) FROM:

THRU:

TO: DonAtwood, Entomologist

### [t~ 

# /JJ't,**~/ ~**  Biological Analysis Branch Rafael A. Prieto, Environmental Protection Speciali;l},

# 1M}t{ Science Information and Analysis Branch 

# vvr; -'
Derek Berwald, Economist 

## 0 1

### ~**~** Economic Analysis Branch

### ~ 

## W0. Biological and Economic Analysis Divisi n (7503 Arnet Jones, Chief (} 

# _o;J Biological Analysis Branch**~-** ,( Diann Sims, Chief

## M,**I'.£.41-A'- ~.Y..** **~;;ttJ** Science Information and Analysis Branch Timothy Kiely, Chief

# ~ \A,..

# ~ Economic Analysis Branch '-: ) VV\,; Biological and Economic Analysts Division 503P) Khue Nguyen, Chemical ReviewManager Risk Management and Implementation Branch 1 Pesticide Re-evaluation Division (7508P) 

### Product Review Panel date: December 5, 2012 INTRODUCTION The purpose ofthis document is to convey usage information and a broad overview ofthe pest management roles ofpesticides that are beginning to undergo registrationreview. The anticipated audience consists ofthe team ofEPA staffcurrently evaluatingthe registration status ofabamectin and eventually the general public. This document builds uponthe data already provided inthe usage and label use datapackages that are also providedto Registration Review 1teams by BEAD. The document is based oninformation and data available to BEAD as of November 12, 2012. Abamectin is an insecticide/miticide/nematicide and was initially registered by the Agency in 1986. Abamectin, also known as Avermectin B1, is in the Avermectin chemical family (macrocylic lactones isolated from soil organism Streptomyces avermitilis) and is a natural fermentation product. Abamectin is a mixture containing more than 80% avermectin Bla (5-0- dimethyl avermectin Ala) and less than 20% avermectin B1b (5-0-dimethyl-25-de(lmethylpropyl)-25-(1-methylethl) avermectin Ala). Abamectin is classified bythe Insect Resistance Action Committee (IRAC) as a Group 6 insecticide, subgroup Avermectins/Milbemycins, impacting nerve and muscle actionthrough chloride channel activation. The main target pests for abamectin include; nematodes (i.e. reniform and root knot), mites (i.e. 2 spotted spider, pacific spider, and citrus rust), asian citrus psyllid, leafminers, ants, silverfish, and cockroaches.


### COMMON FORMULATIONSAND APPLICATIONMETHODS Abamectin is formulated as granular, pelleted, tabletted, impregnated material, water dispersible granules, emulsifiable, flowable, soluble concentrate, solution-ready-to-use, and pressurized liquid and it is applied as aerial, banded, broadcast, ground, seed treatment, and spottreatment.


### USE SITES Agricultural Use Sites Abamectin is an insecticide registered for use on cotton, almond, oranges, pears, grapefruit, grapes, com, strawberries, tomatoes, lettuce, walnuts, apples, lemons, celery, avocados, spinach, peppers, cantaloupes, potatoes, plums/prunes, cucumbers, cherries, squash, peaches, pumpkins, onions, limabeans, apricots, beans (snap, bush, pole, string), alfalfa, pecans, and broccoli. Non-Agricultural Use Sites Abamectin is an insecticide registered for use onpoultryhouses, and agricultural premises, forest trees, herbaceous plants, ornamental plants, lawns and turf, woody shrubs and vines, domestic dwellings (private or commercial), recreational areas, commercial transportation facilities, food and feed processingplants, eating establishments, dairy cattle, and distribution facilities.


### USAGE Based onprivate marketpesticide usage data from 2006-2011, abamectin's annual agricultural usage averaged 57,000pounds ofactive ingredient (A. I.) treating an approximately 4 million acres, for an average application rate ofO.Ol pounds per acre. From 2006-2011, cotton (53%), almonds (18%), and oranges (8%) accounted for the largest percentages ofusage interms oftotal pounds ofA. I. applied. Forthe sameperiod oftime cotton 2(53%), almonds (18%), and oranges ( 1 0%) accounted for the largest percentages oftotal area treated (TAT). This implies that the average application rate for cotton and almonds is similarto the overall average rate while the average applicationrate on oranges is somewhat less than the overall average. As seen onTable 1below, the states with highest pounds (lbs.) applied and total area treated (TAT) for abamectin are California, Florida, Texas, and Georgia. The average application rate in Floridawill be somewhat lowerthan the national average while rates inthe other states will be similarto the national average.

(Proprietary data, 2006-2011).
USE TRENDS Agricultural Figure 1depicts usage trends ofabamectin, in terms ofpounds A. I. applied, in the agricultural market. Abamectin usage remained constant from 1998 through 2005. Since 2005, there has been a steady increase in the usage ofabamectin on surveyed agricultural crops. However, it should be pointed outthatthere has been a shift in the composition ofprimary crops being treated with abamectin from the earlier usage period (1998-2005) to current usage period (2006- 2011). Current usage trends for abamectin are illustrated inFigure 2. Fi ure 

### 1. Total Pounds ofAbamectin A s from 1998-2011 120,000

Lfl 

### 8

....... Year Source: (Proprietary data, 1998-2011) 

### 3

### Fi ure2. Pounds ofAbamectin A 60,000

0 2006 2007 2008 2009 Year 2010 2011 • cotton

• Almonds

• oranges

• Other

"Other" refers to (in order ofhigh to low average pounds applied): Pears, Grapefruit, Grapes, Com, Strawberries, Tomatoes, Lettuce, Walnuts, Apples, Lemons, Celery, Avocados, Spinach, Peppers, Cantaloupes, Potatoes, Plums/Prunes, Cucumbers, Cherries, Squash, Peaches, Pumpkins, Onions, Lima Beans, Apricots, Beans (Snap, Bush, Pole, String), Alfalfa, Pecans, and Broccoli
. Source: (Proprietary data, 2006-2011) Agricultural Usage by Crop Reporting District Another measure ofusage is the use intensity. Inthis analysis, the use intensity is expressed as the pounds a.i. applied per 1000 acres ofland in farms. This differs from the applicationrate, which is expressed as the pounds a.i. applied pertreated acres. The average application rate of 0.01lb a.i. per acre implies a rate of 10 lb a.i. per 1000 acres. The maximum intensity observed is about 1.5 lb a.i. per 1000 acres offarmland. Figure 3 spatially represents abamectin's use intensity in the U.S., which is relatively greater in California and Florida.

4

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

Average Pounds Per 1,000Acres of Farmland

- <0.07 0.07-0
.22 

## D o.23-o.45 0.46- 0.78 0.79- 1
.5
This is a map ofagricultural pesticide usage at the Crop Reporting District (CRD) level prepared by BEAD for use in the Environmental Fate and Effects Division documents. These maps are used to help visualize where the pesticide being considered is most likely to be used and can be helpful in scenario selection and placing the exposure assessment in context. CRDs are boundaries created by USDA NASS which are aggregates ofcounties (USDA, 20I0). Pesticide usage is displayed as average pounds (for the years 2006- 2010) per 1,000 acres of farmland in a CRD to normalize for the variation in farmland between CRDs. Farmland acreage was obtained from USDA (2007). Farmland or "land in farms" is defined as follows: The acreage designated as "land in farms" consists primarily ofagricultural land used for crops, pasture, or grazing. It also includes woodland and wasteland not actually under cultivation or used for pasture or grazing, provided it was part of the farm operator's total operation. Large acreages of woodland or wasteland held for nonagricultural purposes were deleted from individual reports during the edit process. Land in farms includes CRP, WRP, FWP, and CREP acres. Land in farms is an operating unit concept and includes land owned and operated as well as land rented from others. Land used rent free was reported as land rented from others. All grazing land, except land used under government permits on a per-head basis, was included as "land in farms" provided it was part ofa farm or ranch. Land under the exclusive use of a grazing association was reported by the grazing association and included as land in farms. All land in American Indian reservations used for growing crops, grazing livestock, or the potential of grazing livestock was included as land in farms. Land in reservations not reported by reservation, individual American Indians or non5Native Americans was reported in the name ofthe cooperative group that used the land. In many instances, an entire American Indian reservation was reported as one farm (2007 Census ofAgriculture, USDA). Usage is based on private market surveys ofpesticide use in agriculture (Proprietary Data, 2006-2010). The survey data are limited to the states that represent the top 80-90% of acreage for the individual crops, therefore, use may be occurring in regions outside the scope of the survey. CRDs showing no usage of pesticides may be due to either the lack ofpesticide use in the region or non-participation in the agricultural surveys. In addition, across the years, there may be variations in the specific crops included in the CRD survey. This may result in a lower annual average for the CRD. This map displays ratio data (i.e., average pounds per I,000 acres offarmland) summarized at a very highlevel. Readers are strongly cautioned against trying to over interpret the map without examination of the underlying data. The underlying data may explain some ofthe many reasons that a Crop Reporting District may have a high value for a particular active ingredient such as significant acreage (compared with the CRD as a whole) ofa crop or crops with a high application rate and frequency ofapplication. 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. Scale and units of measurement do matter and may be different between maps. Sources: Proprietary Data. 2006-2010 USDA, 2006-2010. NASS Crop Reporting Districts. Online: http://www.ers.usda.gov/briefing/arms/resourceregions/resourceregions.htm#nass
. USDA, 2007. Census ofAgriculture. Online: http://www.agcensus.usda.gov/Publications/2007/index.asp
. Non-Agricultural Usage According to Kline (2006), approximately 2,000 pounds ofabamectin were reported as being used inthe household and houseplant consumer markets. The reported data shows that consumer use accounts for all ofnon-agricultural usage. Itis importantto note thatthis data is dated but is presented inthis document for reference.
BIOLOGICAL ASPECTS RELEVANT TO ABAMECTIN In addition, to considering the importance ofan insecticide relative to the totallbs. applied, it is also important to consider insecticide use interms ofpercent crop treated. Inrelation to percent crop treated, abamectinplays an importantrole in the production ofmajor crops (greaterthan 300,000 acres) and minor crops (less than 300,000 acres). Only one major crop, oranges, has greaterthat 20% crop acres treated with abamectin. In contrast, numerous minor crops have greaterthan 20% ofcrop acres treated with abamectin including; almonds, avocados, cantaloupe, celery, grapefruit, honeydew melon, lemons, pears, spinach, strawberries, tangelos, and tangerines. Dueto the general reduced availability ofregistered insecticides for use onminor crops, abamectin has an important role in minoruse crop production inthe United States.

6Foliar application ofabamectin is safer onparasites and predacious mites ofthe targetpests than some ofthe alternative insecticides. Therefore, abamectin is useful in development ofIPM programs which incorporate biological control as a control strategy. The agricultural use of abamectinhas expanded since 2006. This coincides withthe registration ofabamectin for use as a seed treatment in cotton. The rapid adoption ofabamectin as a nematicide seedtreatment on cotton reflectedthe uncertainty inthe future availability ofaldicarb. The Agency decided to cancel aldicarb and endproduction by December 31, 2014, end distribution and sale by December 31, 2016, and end use by August 31, 2018 (to allow growers to exhaust any remaining product). However, industryhas since renewed aldicarb registration with the Agency. Therefore, any future expansion ofabamectin use as a cotton nematicide will be dependent upon abamectin effectiveness and market competition with aldicarb. Abamectin is effective for use against non-agricultural pests (baits and gels) as it is a delayedaction insecticide and doesn'tprovide immediate insect death. The benefit ofdelayed-action insecticides as compared to those that kill instantly is that the poisoned insect is allowed time to travel backto the colony and spread the poisonto other insects eitherthrough contact orfood sharing (ingestion)
HISTORY OF BEAD ASSESSMENTS FORABAMECTIN BEAD has not written a full benefit assessment for abamectin. BEAD has reviewed section 18 requests for abamectin, including use for controlling thrips in onions because ofresistance to otherpesticides, and to control spider mites on limabeans, also due to resistance.
INFORMATION THAT MAYBE USEFUL FORBEAD'S FUTURE WORK ON ABAMECTIN Obtaining additional information ontypical abamectin use inthe non-agricultural sector would improve future BEAD assessments ofthe importance ofabamectin and may be required as part ofthe registration review ofthis pesticide. Requested data should include, butnotbe limited to, applicationtiming, application rate, application method, and application frequency.
REFERENCES Kline & Co., 2006 PMEP. 1994. Pesticide Information Profile

- Abamectin. Pesticide Management Education Program

- Cornell University Cooperative Extension. Available at: http:/ /pmep.cce.cornell.edu/profiles/extoxnet/24d-captan/abamectin-ext.html



### 7Proprietary Data. 1998-2011 Proprietary Data. 2006-2010 USDA, 2006-2010. NASS Crop Reporting Districts. Online: http://www.ers.usda.gov/briefing/arms/resourceregions/resourceregions.htm#nass
. USDA, 2007. Census ofAgriculture. Online: http://www.agcensus.usda.gov /Publications/2007/index.asp
.

8