The Trump administration has given the green light to three new pesticides that contain persistent carbon-fluorine bonds, drawing sharp criticism from environmental advocates who argue the chemicals fit the international definition of “forever chemicals.” The Environmental Protection Agency, however, disputes that characterization, standing by its narrower regulatory definition.
This week, the EPA approved epyrifenacil, diflufenican, and trifludimoxazin—each containing single-fluorinated-carbon molecules. While the agency maintains these compounds lack the persistence and bioaccumulation traits that define PFAS under its 2023 rule, critics point to the broader definition used by the Organization for Economic Cooperation and Development (OECD), which considers any carbon-fluorine bond a potential forever chemical.
“They’re all breaking down into things that are going to stick around forever,” said Nathan Donley, environmental health science director at the Center for Biological Diversity. He warned that the approvals represent irreversible decisions with long-term consequences.
The EPA spokesperson, in a statement to The Hill, defended the approvals, noting that the Biden-era EPA deliberately excluded single-fluorinated-carbon compounds from its PFAS definition after a public rulemaking process. “That exclusion was deliberate, grounded in extensive scientific evidence and public input showing that molecules with only one fluorinated carbon lack the persistence and bioaccumulation properties that all PFAS exhibit,” the spokesperson said.
The approved pesticides are intended for use on major crops: epyrifenacil on canola, field corn, soybeans, and wheat; diflufenican on corn and soybeans; and trifludimoxazin on citrus, corn, peanuts, and soybeans. The EPA acknowledged that trifludimoxazin shows “suggestive evidence” of carcinogenic potential in animal studies, along with thyroid and liver effects, but claimed the imposed usage limits are sufficient to mitigate risks. Epyrifenacil was linked to liver and blood impacts in animal tests.
Donley raised particular concern that some of these compounds could degrade into trifluoroacetic acid (TFA), a persistent chemical increasingly found in water sources. The EPA countered that it accounted for this breakdown pathway, setting dietary limits for epyrifenacil roughly 1,800 times lower than doses where TFA-related effects might occur.
The approvals come amid growing scrutiny of PFAS and pesticides from the “Make America Healthy Again” movement, which has criticized both the chemical industry and agricultural giants. Late last year, the EPA approved two other pesticides that meet the OECD’s PFAS definition, fueling outrage among MAHA activists. In a related development, MAHA activists were furious after the Supreme Court sided with Monsanto on Roundup labels, highlighting the broader battle over chemical regulation.
The EPA spokesperson emphasized the agricultural benefits, stating the pesticides “help farmers control economically damaging, herbicide-resistant weeds like Palmer amaranth, and they support regenerative, soil-health practices like no-till.” The agency also asserted that its reviews thoroughly examine persistence and bioaccumulation, and that single-fluorinated-carbon compounds do not exhibit these properties.
Donley countered that these approvals could have lasting environmental and health impacts. “These terrible pesticide approvals will outlast almost anything that Trump has done these past few years, because they are forever decisions,” he said. “Releasing forever chemicals is a forever decision, because there’s no going back.”
The debate underscores the ongoing tension between agricultural interests and environmental health advocates, as the EPA navigates conflicting definitions and scientific assessments of what constitutes a forever chemical.
