The Iowa Farm Bureau Federation (IFBF), the largest general farm organization in the state with more than 153,000 members, appreciates the opportunity to file these comments on the Environmental Protection Agency’s Proposed Interim Decision (PID) for atrazine and the other triazines. Farm Bureau policy supports the continued safe use of atrazine and other triazines. Atrazine is still one of the most widely used herbicides on corn and a key tool in Iowa’s Nutrient Reduction Strategy, developed in 2013 to reduce phosphorus and nitrogen loss and improve surface water quality. Iowa farmers use atrazine on at least 65 percent of corn acres to control broadleaf weeds, more than any other crop protection compound, because it works, it's cost-effective, and it's safe for farmers and the environment.
The IFBF supports the agency’s recommendation in the PID for an ecological level of concern (LOC) of 15 parts per billion (ppb). This corrects a 2016 ecological risk assessment recommendation that would have lowered the LOC to 3.6 ppb. This low of a LOC would have effectively eliminated the use of the herbicide on Iowa corn acres and other crops across the nation.
While the PID’s LOC of 15 ppb results in unchanged use rates for Iowa corn, there still is concern that perceived ecological/aquatic community impacts resulting from the continued inclusion of some faulty science studies – and ignoring several high-quality studies - might result in EPA being forced to lower use rates in the future to a level that would render the product virtually useless. This opens the door to future regulatory uncertainly. This faulty science needs to be removed from the amended PID documents.
The faulty science (e.g, the 11 cosom studies identified by the agency’s own Science Advisory Panel in 2012, the flawed Medaka fish study, and the discounting/misinterpretation of results from the SAP-requested Baylor study), needs to be removed or corrected because the next step in the reregistration process is the new Endangered Species Act assessment and consultation process. EPA will be forwarding its PID and triazine science to the U.S. Fish & Wildlife Service and the National Marine Fisheries Service for this ESA assessment and consultation. While the PID is, in effect, an overall good thing for the continued, safe use of these important crop protection compounds, the troublesome, problematic science in it may be relied on by other agencies to argue for further use restrictions. The IFBF asks EPA to remove these problematic studies or correct their faulty conclusions as part of its final review.
Otherwise, the continued inclusion of faulty studies opens the door to recommended use rate limitations from other agencies. When the final consultation recommendations come back to EPA from the other federal agencies, you will have to decide how to respond to any unsound ESA concerns, concerns that are not based on good science. EPA should only use the best science recognized by the agency’s own SAPs. Therefore, the final PID language is critically important. The continued use of some of this faulty underlying science opens the door to additional lawsuits from activists, other agencies or registrants. This unnecessary, future regulatory uncertainty is very problematic for Iowa corn farmers and our members.
Iowa farmers have used atrazine very responsibly. The USDA’s National Agricultural Statistics Service estimates the actual atrazine use rate in Iowa is 1.037 pounds per acre per year. The maximum labeled rate for atrazine in most application situations in Iowa is 2 pounds per acre. Many farmers and Certified Crop Advisors (CCAs) are concerned that application rates as low as 8 ounces per acre limit the ability to include it in mixes with other products, as it would reduce the efficacy of them all, especially on post-emergent broadleaf weeds in corn where more than a half-pound per acre is often necessary to be effective. Some soils and situations call for at least three-quarters to 1 pound per acre in post-emergence applications, Iowa farmers and CCAs say. Yet, there are still situations or fields where one to two pounds are sometimes necessary.
Now it’s up to EPA to act responsibly in its amended proposed interim decision. Options and flexibility on the label are necessary for Iowa farmers. A lower labeled rate resulting from a reliance on faulty science by some federal agencies may lead to Iowa farmers someday using more expensive, less effective products, with possible weed resistance developing and/or the need to increase tillage to control weeds. These are outcomes that EPA has also said it does not want.