PFAS pesticides: Trump EPA approvals raise concern

President Donald Trump’s administration has approved five pesticides that many scientists and environmental advocates say are PFAS “forever chemicals,” intensifying a dispute over how the United States defines and regulates the substances.

The Environmental Protection Agency uses a narrower definition of per- and polyfluoroalkyl substances that excludes the newly approved herbicides, insecticides and fungicides. The agency says the products pose no threat to human health and argues that pesticides are important for food supplies, are reviewed before approval and that single-fluorinated chemicals can be less toxic than alternatives.

The EPA also says the pesticides are registered or proposed in the European Union, Canada and Australia.

Many scientists and advocacy groups use a broader definition adopted by the Organization for Economic Co-operation and Development in 2021, covering any molecule with a single fully fluorinated carbon atom. Roughly half of US states, Congress and the Pentagon have upheld that definition, as did 150 scientists in a 2024 consensus statement.

Critics say the pesticide approvals may carry hidden risks, including because many such pesticides break down into trifluoroacetic acid, or TFA, which is now found extensively in water. The EU’s food safety agency last week cut its acceptable daily intake for TFA. In June, the European Chemicals Agency classified TFAs as toxic to reproduction in a non-binding opinion based on animal studies.

Trifludimoxazin, one of the newly approved herbicides, has “suggestive evidence of carcinogenic potential,” according to the EPA’s own review.

Nathan Donley of the Center for Biological Diversity, who led a 2024 analysis of past pesticide ingredients, told AFP that the issue had been “conveniently swept under the rug” by multiple administrations and was “definitely getting worse.” His study found 66 previously approved pesticide ingredients would have met the OECD definition of PFAS.

Environmental Working Group scientist Varun Subramaniam told AFP that an analysis of produce samples found PFAS pesticide residues were common on US peaches and plums.

Criticism has also focused on former lobbyists in senior EPA posts. A Freedom of Information Act request led by Donley found that EPA officials, including agency chief Lee Zeldin, coordinated edits last November to the agency’s webpage on PFAS and pesticides, removing acknowledgement of the more widely accepted definition.

CropLife America, the pesticide industry’s trade association, told AFP it did not coordinate with the EPA over the timing of its submission to the agency, but resubmitted its manuscript to reference the revised page.