The US Environmental Protection Agency finalized approval of four new pesticide active ingredients—fluoxapiprolin, trifludimoxazin, diflufenican, and epyrifenacil—and expanded approved uses for two existing pesticide chemicals, chlormequat and bifenthrin, all in the past month. The actions have drawn scrutiny because several of the newly approved fluorinated pesticides are being characterized by environmental groups such as the Center for Biological Diversity (CBD) as per- and polyfluoroalkyl substances (PFAS), or forever chemicals.
Industry groups and the EPA attribute the agency’s recent actions to President Donald J. Trump’s June 25 executive order on regenerative agriculture, which calls on federal agencies to strengthen farm resilience, expand access to biological products and other alternatives, and reduce reliance on “chemical crop protection tools.”
The first initiative of the executive order—Section 2, Ensuring Access to Modern Products and Practices and Accurate Labeling—directs the EPA to “prioritize registration actions related to substances that can be used as alternatives to older active ingredients.”
“It was extremely encouraging to see EPA cite Section 2 of the executive order to propose . . . new pesticide uses,” Manojit Basu, vice president of science policy and regulatory affairs at CropLife America (CLA), tells C&EN. Among the recent approvals, he referenced three additional recent EPA new use proposals of conventional chemical pesticides. “Following issuance of the executive order, pesticide actions began moving again.”
Other industry groups, including the Weed Science Society of America and the American Farm Bureau Federation, also applauded the recent pesticide approvals.
Defining PFAS
The PFAS debate surrounding these chemicals centers on how the term is defined. The Organisation for Economic Co-operation and Development (OECD) takes a structural approach that defines PFAS broadly as substances containing at least one fully fluorinated carbon atom. Under that definition, three of the newly registered active ingredients—trifludimoxazin, diflufenican, and epyrifenacil—fall within the PFAS category because they contain fully fluorinated carbon groups.
“The EPA has stated in press materials that these new fluorinated pesticides are not PFAS. That assertion is based on the fact that they do not meet the chemicals office’s unilateral regulatory PFAS definition,” the Center for Biological Diversity writes in a June 30 statement. “Using the scientific definition of a PFAS that is widely accepted in this country and around the world, these pesticides are PFAS.”
The EPA’s press office denies these claims. “While these pesticides are single fluorinated carbon compounds, they are not forever chemicals and do not pose any risks of concern when used as labeled,” the agency says in an emailed statement.
The approvals of these chemical ingredients coincide with the administration’s push for nonchemical alternatives in line with the executive order.
‘Alternative’ tools
Among other provisions, the executive order instructs the EPA to identify barriers to regenerative practices, accelerate review of biological pesticides and other alternatives, and examine ways to reduce farmers’ dependence on synthetic chemical inputs while maintaining productivity.
Asked how the recent pesticide approvals align with the order’s intent to promote alternative technologies, the EPA’s press office tells C&EN that “Safe, effective, well-regulated herbicides—like the ones EPA recently registered—provide farmers an important weed-management alternative to intensive soil tillage, which can increase runoff and erosion, [and] reduce soil organic content, among other challenges.”
Basu at CLA applauds the administration’s encouragement of biologicals, but says that “biological products are currently complementary tools more often than direct replacements for conventional pesticides in major US crops.” For herbicide resistance management, he says, “biologicals are not an option.” For managing weeds, he continues, “farmers primarily rely on conventional chemistries.”
The executive order directs the EPA to work with the Departments of Agriculture and Health and Human Services to develop a research framework for studying cumulative chemical exposures in the US food supply. The order also calls on federal agencies to identify regulatory barriers and expand public-private partnerships to support regenerative agriculture and precision-farming tools.
