UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON D.C., 20460 

OFFICE OF CHEMICAL SAFETY AND POLLUTION PREVENTION 

MEMORANDUM 

DATE: November 15, 2013 

SUBJECT: Abamectin (PC Code 122804): PRD Response to Comments on Registration 

Review Preliminary Work Plan 

FROM: Khue Nguyen, Chemical Review Manager 

Mark Suarez, Acting Team Leader 

Risk Management and Implementation Branch 1 

Pesticide Re-evaluation Division (7508P) 

THROUGH: Neil Anderson, Branch Chief 

Risk Management and Implementation Branch 1 

Pesticide Re-evaluation Division (7508P) 

TO: Abamectin Registration Review Docket 

Docket Number: EPA-HQ-OPP-20 13-0360 

www.regulations.gov 

On June 26, 2013 EPA opened a 60-day public comment period on the preliminary work plan (PWP) 

for the registration review of abamectin. The comment period ended on August 26, 2013. During the 

public comment period the Agency received 8 submissions. Comments were submitted by the 

technical registrant, Syngenta Crop Protection, the University of Hawaii at Manoa, the Western 

Integrated Pest Management Center, the Northwest Horticultural Council, the Washington State Potato 

Commission, the Wisconsin Potato & Vegetable Growers Association, the Idaho Potato Commission, 

and the FIFRA Endangered Species Task Force (FESTF). 

Below are PRD's responses to those comments pertaining to the use and usage of abamectin or 

pertaining to the general abamectin registration review program. Comments regarding the 

environmental fate or effects of abamectin have been addressed by the Environmental Fate and Effects 

Division's (EFED) document, EFED Response to Public Comments Submitted in Response to the 

Abamectin Registration Review Problem Formulation PWP (dated November 5, 2013). There were no 

comments pertinent to the health effects scoping document on the planned human health risk 

assessments. 

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University of Hawaii at Manoa Comment: The University of Hawaii at Manoa submitted typical 

application rates, methods of application, application timing and frequency, and other application 

information for the following abamectin use sites: bulb onions, tomato and eggplant, turf, and 

ornamental landscape and nurseries. 

EPA Response: The Agency thanks the University of Hawaii at Manoa for information on the 

application of abamectin and will incorporate this information into the registration review risk 

assessment. 

Washington State Pest Management Resource Service Comment: The Washington State Pest 

Management Resource Service submitted information on almond use in California from the Almond 

Board of California. Abamectin's importance for controlling web-spinning spider mites in almond 

crops was highlighted. Spider mites are problematic in almond orchards during drought, high 

temperature, and/or dusty conditions. The industry's reliance on pyrethroids to control navel 

orangeworms has the side effect of causing mite population flare ups and necessitates the use of 

abamectin as a preventive control. Information was also submitted for abamectin usage on cotton, 

blueberries and raspberries, grapes, hops, ornamentals, potatoes, and tree fruits (particularly pears and 

apples). Abamectin is used to control European red mite, McDaniel spider mite, tentiform leaf miner, 

two-spotted spider mite, white apple leafhopper, pear psylla, pear rust mite, and yellow mite. 

EPA Response: The Agency thanks the Washington State Pest Management Resource Service and 

the Almond Board of California for this information and will consider it during abamectin's 

registration review. 

Northwest Horticultural Council Comment: The Northwest Horticultural Council provided 

application rate information and treated acreage in Washington and Oregon for abamectin use on 

apples, pears, and stone fruit. The council also provided maximum residue limits for abamectin in 

Indonesia, Russia, China, Canada, Brazil, and the EU. The council commented that Saudi Arabia did 

not have established MRLs for apple and pear for abamectin. 

EPA Response: The Agency thanks the Northwest Horticultural Council for the usage infonnation, 

which will be considered during the registration review of abamectin. During registration review, the 

Agency will work to minimize trade irritants and harmonize US tolerances with MRLs with its trading 

partners, to the extent feasible (and consistent with domestic law). To facilitate this, the Agency works 

with the USDA Foreign Agricultural Service and the United States Trade Representative to identify 

potential trade irritants. EPA is currently working with some of the countries identified by Northwest 

Horticultural Council to assist with the development of science-based MRLs. 

Washington State Potato Commission Comment: The Washington State Potato Commission 

provided information regarding abamectin usage on potatoes in Washington and commented in favor 

of the continued registration of abamectin, highlighting its importance for treating potato psyllids, 

which carry the "zebra chip" disease. Zebra chip disease was only recently detected in the state and 

usage of abamectin has increased in Washington because abamectin is able to control potato psyllids in 

the egg, nymph, and adult stage. Washington State is the second largest producer of potato in the 

country and its potato industry is worth $4.7 billion dollars. 

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EPA Response: The Agency thanks the Washington State Potato Commission for this information 

and will consider it during the registration review of abamectin. 

Wisconsin Potato & Vegetable Growers Association Comment: The Wisconsin Potato & 

Vegetable Growers Association commented in favor of the continued registration of abamectin, 

highlighting abamectin 's importance in its integrated pest management program. The Wisconsin 

potato and vegetable industry is valued at $9 billion. 

EPA Response: The Agency thanks the Wisconsin Potato & Vegetable Growers Association for its 

comment and will consider it during the registration review of abamectin. 

Idaho Potato Commission Comment: The Idaho Potato Commission commented in favor of the 

continued registration of abamectin, highlighting abamectin's importance· to the potato industry for 

control of potato psyll ids, which cause the devastating "zebra chip" disease. Idaho is the largest 

producer of potato in the United States and its potato industry is worth billions and provides over 13 

thousand potato-related jobs. 

EPA Response: The Agency thanks the Idaho Potato Commission for its comments and will consider 

them during registrati'on review. 

FESTF Comment: The FIFRA Endangered Species Task Force (FESTF) noted that Syngenta Crop 

Protection, Cheminova Inc., and Nufarm Limited were members of FESTF and have access to its data 

for the abamectin endangered species assessment during registration review. 

EPA Response: The Agency thanks FESTF for its comment and will consider it as it conducts the 

registration review of abamectin. 

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