UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

DEC 2 0 2013 

MEMORANDUM 

SUBJECT: BEAD Response to Atrazine Public Comments 

FROM: Bill Phillips, II, Ph.D., Agronomist /J#~ 

Biological Analysis Branch 151 \ I l \ rG 

Derek Berwald, Ph.D., Economist ,fV VV\._ \Y(J 

Economic Analysis Branch 

Elizabeth Hill, Economist 

Economic Analysis Branch 

OFFICE OF CHEMICAL SAFETY 

AND POLLUTION PREVENTION 

THRU: 

Sepehr Haddad, Environmental Protection Specialist ~ 1 ~ Science Information and Analysis Branch ~ r 

Biological and Economic An lys· ivision (7503P) 

Biological 

Arnet Jones, 

Analysis 

Chief 

Branch 

~ 

Biological and Economic Analysis Divi (7503P) 

Timothy Kiely, Chief ~,;f Economic Analysis Branch J 

Diann Sims, Chief 

Science Information and Analysis Branch 

Biological and Economic Analysis Division (7503P) 

TO: Kaitlin Keller, Chemical Review Manager 

Risk Management and Implementation Branch III 

Pesticide Re-evaluation Division (7508P) 

PRODUCT REVIEW PANEL: November 20,2013 

1 
The Environmental Protection Agency (Agency) is implementing the registration review 

program pursuant to Section 3(g) of the Federal Insecticide, Fungicide, and Rodenticide Act 

(FIFRA), and will review each registered pesticide every 15 years to determine whether it 

continues to meet the FIFRA standard for registration. Changes in science, public policy, and 

pesticide use practices occur over time. The registration review program is intended to make sure 

that, as the ability to assess risk evolves and as policies and practices change, all registered 

pesticides continue to meet the statutory standard. The public phase of registration review begins 

when the initial docket is opened for each case. Information on this program is provided on the 

Agency's website. (EPA 2012) 

Registration review may consist of a review of available information on a pesticide, risk 

assessments, and, potentially, risk management. The Biologic and Economic Analysis 

Division's (BEAD) role is to provide relevant use and usage information for risk assessments 

and to conduct benefit/impact assessments to inform risk management. In the case of 

agricultural uses, these impacts could include changes in yield, in the quality of produce, and/or 

the cost of producing the commodity that affect producers' income and, potentially, could affect 

consumers through the supply and price of commodities. 

On June 26, 2013 the federal docket (HQ-OPP-2013-0266) for the registration review of the 

active ingredient atrazine was opened to the public to receive comments regarding all 

preliminary work for this herbicide, the docket subsequently closed on August 26, 2013. This 60 

day comment period provided the public the opportunity to submit comments about the work that 

has been completed up to the June docket opening. The Agency received comments with some 

of these comments being focused on the benefits of atrazine as well as the alternatives to using 

atrazine. In this document BEAD is responding to the comments that were submitted to the 

atrazine docket. Since many of the comments addressed the same concerns, BEAD has 

summarized the comments and presented the responses in this document rather than responding 

to each comment individually. 

EPA thanks the public for comments provided to the atrazine docket during the public comment 

period. Information provided to the docket and any additional information submitted by the 

public regarding the agronomic, weed science and/or economic relevance of atrazine could be 

useful in future alternatives and/or benefits analysis. 

Comments and Responses 

Economic impacts 

o Comments include: 

• Minimizing the amount of chemical applied improves profit margins on 

farms. EP A-HQ-OPP-20 13-0266-0061 (Illinois Com Growers 

Association) 

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• Research shows that the use of atrazine boosts com yields by 5.5 bushels 

per acre, at a significantly lower cost than other herbicides. EPA-HQOPP-2013-0266-0078 (Kansas Com Growers Association) 

• Atrazine helps increase yield potential through better weed control and at 

a low cost to fanners. Despite intensive research by weed scientists to 

find alternatives to Atrazine, it continues to be one of the best low-rate 

products available to fanners at a reasonable cost. EPA-HQ-OPP-2013-

0266-0300 (Kentucky Com Growers Association) 

• It [atrazine] is a low cost treatment. EPA-HQ-OPP-2013-0266-0019 

(Maryland Grain Producers Association) 

• If unable to utilize atrazine in their operation, the cost to fanners could be 

in the millions of dollars when losses to yield, reduction to ease to 

stewardship and increased herbicide costs are calculated. Weeds are one 

of the largest yield thieves in field crops. Lack of weed control due to 

herbicide resistance and effective product availability is an ever increasing 

cost and concern for fanners. EPA-HQ-OPP-2013-0266-0020 (Missouri 

Com Growers Association) 

• U.S. fanners have relied on atrazine for cost-effective, broadleafweed 

control in com. EPA-HQ-OPP-2013-0266-0074 (National Com Growers 

Association) 

• Atrazine helps to increase yields through better weed control at a cost that 

is not prohibitive to fanners. EPA-HQ-OPP-2013-0266-0060 (Andy 

Thompson, Ohio State Rep) 

• At a time when grain prices are dropping and the cost to produce that grain 

is skyrocketing, maintaining the ability to use important and reasonably 

priced products like atrazine and simazine cannot be stressed enough. 

EPA-HQ-OPP-2013-0266-0068 (Ohio Com and Wheat) 

• Atrazine helps increase yields through better weed control, and at a low 

cost to fanners. Despite intensive research by weed scientists to identify 

atrazine alternatives, low rates of atrazine in herbicide programs continue 

to produce yield benefits at a reasonable cost. EPA-HQ-OPP-2013-0266-

0085 (Oregon Farm Bureau) 

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o Response 

• EPA will take these comments into consideration if an impact/benefits 

assessment is conducted for atrazine. There are over 200 published 

studies analyzing how the absence of atrazine would be reflected in corn 

and sorghum producers' budgets (Fawcett, 2006). Some studies (WI 

DOA, 2011; Ackerman, 2007; EPA, 2002; and Coursey, 2007; Fawcett, 

2006) conclude that growers may face an increase in the cost per acre 

and/or a decline in yields when switching from atrazine to alternative 

herbicides. However, economic impacts vary widely across studies. More 

current analyses would be necessary, as pesticide prices fluctuate regularly 

and are influenced by a variety of factors. Commenters are always 

encouraged to share with the EPA Office of Pesticide Programs any 

current data or studies--especially peer-reviewed studies-that address 

the economic benefits of atrazine. 

o References: 

Ackerman FA. 2007. The Economics of Atrazine. International Journal of 

Occupational Environmental Health. 13: 441-449. 

Coursey D. 2007. Illinois Without Atrazine: Who Pays? Online: 

http://www.ilfb.org/uploads/files/Atrazine_Final_Report_02-27-07 _13072.pdf. 

Accessed March 21,2012. 

Fawcett RS. 2006. Two Decades of Atrazine Yield Benefits Research. Triazine 

Network, 2006. Online: http://www.ksgrains.com/triazine/. Accessed March 

21, 2012. 

U.S. Environmental Protection Agency. 2002. Assessment of Potential 

Mitigation Measures for Atrazine. Biological and Economic Analysis Division, 

Office ofPesticide Programs. 

Wisconsin Department of Agriculture (WI DOA). 2011. Final Report on the 2010 

Survey of Weed Management Practices in Wisconsin's Atrazine Prohibition 

Areas. 

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Use and Usage 

o Comment (EPA-HQ-OPP-2013-0266-0299) 

• Syngenta states that they are working with the other atrazine technical 

registrants to make a table to be provided to EPA that lists current atrazine 

uses, products and formulation types. The table will include clarification 

for some uses as discussed at the Atrazine Focus Meeting. 

• There are a number of discrepancies on the EPA provided table. Syngenta 

will be addressing these on the Use Table (matrix) as mentioned above to 

be provided to EPA. 

• Syngenta states that emulsifiable concentrate is incorrectly listed as a 

formulation type for atrazine. 

• Some Syngenta suspension concentrate formulations are incorrectly 

identified by EPA as emulsifiable concentrates. Corrections to formulation 

type will be included on the atrazine use table being prepared 

o Response 

• Since Syngenta is working with the other atrazine technical registrants to 

make a table to be provided to EPA that lists current atrazine uses, 

products and formulation types, and the table will include clarification for 

some uses as discussed at the atrazine Focus Meeting, once EPA receives 

the information we will incorporate all necessary changes as appropriate. 

EPA thanks Syngenta and other technical registrants for the information. 

Weed Control and Agronomics 

I. Importance of atrazine in weed management 

o Comments 

• Atrazine has been proven effective for over 50 years. 

• Atrazine has been used effectively to control weeds in com, sorghum and 

sugar cane production. 

• Atrazine has been used effectively to control weeds in nonagricultural 

areas such as forest tree establishment and turfgrass. 

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• Atrazine is a significant tool for a farmer to control weeds. 

• Atrazine controls a broad spectrum of weed species over a long period of 

time. 

• Atrazine controls problematic weeds such as Palmer amaranth and 

waterhemp. 

• There is no alternative to atrazine. 

• There are alternative pest management practices and less toxic pesticides 

that can be used as alternatives to atrazine. 

• Integrated pest management and organic production are examples of 

alternatives to atrazine use. 

o Response 

• The EPA is aware that atrazine has been used for many decades to control 

a broad spectrum of weeds in agricultural crops such as com, sorghum, 

and sugarcane as well as in nonagricultural crops such as forest tree 

establishment and turfgrass. It is understood that there is no single 

herbicide that has all of the characteristics of atrazine. The EPA is also 

aware that no single herbicide is required under all conditions and that 

atrazine may not be needed under certain circumstances where 

combinations of herbicides and/or alternative practices may be sufficient 

to control weeds. 

II. Additional benefits of atrazine 

o Comments 

• Atrazine is important in aiding in increased crop yields. 

• Atrazine is important in maintaining reduced and no tillage cropping 

systems. 

• By supporting no tillage agriculture atrazine allows for a reduction in soil, 

nutrient and pesticides in runoff. 

• Atrazine is an effective tool in managing resistant weeds by being an 

additional mechanism of action in an herbicide combination and/or 

rotation. 

• Atrazine has a broad window of application timing. 

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• Sorghum has very few herbicides and atrazine is a very important tool in a 

crop with a limited number of available herbicides. 

o Response 

• The EPA is aware that the agricultural industry considers atrazine to be a 

significant tool in reducing weed populations, thus resulting in increasing 

crop yield, while also supporting no-tillage practices and resistance 

management practices. The EPA is also aware that atrazine has a broad 

window of application timing and can be used in a number of crops that 

have a limited number of herbicides available, such as sorghum and 

sugarcane. 

III. Managing atrazine in the environment? 

o Comments 

• Growers have been in the forefront of atrazine stewardship. 

• Atrazine is efficacious at lower rates. 

• The efficacy ofherbicide mixtures is enhanced with the addition of 

atrazine. 

• Technologies such as GPS and variable rate application make for safer and 

better control of the herbicide. 

• Many states work with farmers on BMPs to better steward atrazine. 

o Response 

• The EPA appreciates the fact that growers and applicators have worked to 

make atrazine use rates lower over time while still maintaining efficacious 

weed control. In addition, the EPA understands that the use of atrazine in 

some herbicide mixtures can enhance control above that of the individual 

active ingredients. The move toward the use of technology such as GPS 

and variable rate technology are important to the EPA's understanding of 

the use of this herbicide. Information on projects with states and other 

entities regarding BMP and other stewardship projects will be important 

for the EPA to know about moving forward in conducting analyses such as 

alternative assessments or benefits analysis that may be needed for 

registration review. 

7 
Summarized Weed Control 

and Agronomic Comment 

Docket Number 

EPA-HQ-OPP-20 13-0013 

EPA-HQ-OPP-2013-0017 

EPA-HQ-OPP-2013-0018 

EPA-HQ-OPP-2013-0019 

EP A-HQ-OPP-2013-0020 

EPA-HQ-OPP-2013-0025 

EPA-HQ-OPP-20 13-0060 

EPA-HQ-OPP-2013-0061 

EPA-HQ-OPP-20 13-0062 

EPA-HQ-OPP-2013-0065 

EPA-HQ-OPP-2013-0066 

EPA-HQ-OPP-2013-0067 

EP A-HQ-OPP-20 13-0068 

EPA-HQ-OPP-2013-0069 

EPA-HQ-OPP-2013-0070 

EP A-HQ-OPP-2013-0071 

EPA-HQ-OPP-2013-0072 

EPA-HQ-OPP-2013-0073 

EPA-HQ-OPP-2013-0074 

EPA-HQ-OPP-2013-0075 

EPA-HQ-OPP-2013-0077 

EPA-HQ-OPP-2013-0078 

EPA-HQ-OPP-20 13-0085 

EPA-HQ-OPP-2013-0299 

EPA-HQ-OPP-2013-0300 

References 

Commenter 

South Dakota Com Growers Association 

Chemical Industry Council of America 

Iowa Farm Bureau Federation 

Maryland Grain Producers Association 

Missouri Com Growers Association 

American Farm Bureau Federation 

Andy Thompson, Ohio State Representative, 95th District 

Illinois Com Growers Association 

Hawaii Agriculture Research Center 

National Farmers Union 

Texas Seed Trade Association 

Illinois Farm Bureau 

Ohio Com & Wheat Growers Association 

Nebraska Com Growers Association 

Illinois Soybean Association 

Michigan Farm Bureau 

HC&S 

Beyond Pesticides 

National Com Growers Association 

Oregonians For Food & Shelter 

Kansas Grain Sorghum Producers Association 

Kansas Com Growers Association 

Oregon Farm Bureau 

Syngenta Crop Protection 

Kentucky Com Growers' Association 

EPA 2012, Pesticides: Registration Review http://www.epa.gov/oppsrrdl/registration_review/ 

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