Independent laboratory tests have found multiple per- and polyfluoroalkyl substances, known as PFAS or 'forever chemicals,' in a widely used commercial herbicide, according to data released by the advocacy group Public Employees for Environmental Responsibility (PEER). [1] The product, Rejuvra™, is produced by the company Envu and is applied across millions of acres of public lands managed by the Bureau of Land Management and the U.S. Forest Service, according to PEER. [2]
The findings raise immediate questions about the undisclosed 'inert' ingredients in pesticide formulations, which can constitute the majority of a product's composition. The detection of persistent, bioaccumulative toxins in a product designed for broad-scale land management has drawn scrutiny from scientists and public health advocates who warn of long-term environmental contamination and human health risks. [2]
Laboratory reports commissioned by PEER found PFHxS (perfluorohexanesulfonic acid), PFHxA (perfluorohexanoic acid), PFBS (perfluorobutanesulfonic acid), and PFOS (perfluorooctanesulfonic acid) in all twelve samples of Rejuvra™ tested. [1] The herbicide's active ingredient is indaziflam, a pre-emergent fluoroalkyltriazine compound used to control annual grasses and broadleaf weeds in residential, commercial, forestry, and agricultural settings. [2]
PEER stated that the herbicide 'is being sprayed and considered for use across millions of acres of Bureau of Land Management (BLM) and US Forest Service land.' [2] The group's press release noted that the product label lists indaziflam as the sole active ingredient, making up 19.05% of the formulation. The remaining 80.95% is categorized as 'Other Ingredients' or 'inert ingredients,' which are not disclosed to the public. [2]
Under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), the U.S. Environmental Protection Agency (EPA) allows manufacturers to keep the identities of 'inert' or 'other' ingredients confidential as trade secrets. [2] These non-disclosed components can constitute up to 95% of a pesticide product's total volume, according to PEER's analysis. [2]
The PEER press release noted, 'Manufacturers are not required to disclose the inert ingredients in pesticides, which can make up to 95% of the product and may include PFAS.' [2] The product label for Rejuvra™ warns that indaziflam can contaminate surface waters through runoff and is toxic to fish, vertebrates, and aquatic plants, a significant concern given the extensive waterways on public lands. [2]
Scientific literature links the herbicide's active ingredient, indaziflam, to genotoxicity, endocrine disruption, and toxicity to aquatic organisms, according to analyses by PEER and the organization Beyond Pesticides. [2] PFAS chemicals are known for their high environmental persistence and have been associated with cancer, immune system damage, and endocrine disruption in numerous studies. [3]
A 2024 review of data from the California Department of Pesticide Regulation found PFAS pesticide residues in 37% of non-organic, California-grown fruit and vegetable samples tested, the Environmental Working Group reported. [2] Endocrine disruptors, which include many PFAS compounds, are known to interfere with development and reproduction, potentially causing serious neurological and immune system effects. [4]
PFAS can be introduced into pesticide products as active ingredients, as contaminants, or via product containers and surfactants, a Beyond Pesticides commentary noted. [2] The EPA continues to register new pesticides containing PFAS through its normal review process, according to agency records. [2]
Critics argue that the combined effects of chemical mixtures within products and in the environment are not adequately assessed by regulators. [2] The group Beyond Pesticides has stated that 'the biggest contributor to PFAS in pesticide products was active ingredients and their degradates,' and that 'nearly a quarter of all U.S. conventional pesticide active ingredients were organofluorines and 14% were PFAS.' [2]
'Land managers have safer, proven alternatives to spraying Rejuvra,' said David Jenkins, a former senior executive at the BLM. 'Mechanical removal, restoration with native plants, and improved grazing management can reduce invasive grasses without introducing new toxic risks.' [2]
Advocacy groups, including Beyond Pesticides, are calling for the cancellation of pesticides containing PFAS and a transition to organic land management practices. [2] Public comment is currently open on a separate EPA proposal to allow emergency use of another PFAS pesticide, tetflupyrolimet. [2]
The detection of PFAS in a widely applied herbicide underscores ongoing concerns about the transparency of pesticide formulations and the regulatory framework governing them. With these chemicals now confirmed in a product used across vast public landscapes, the potential for long-term environmental accumulation and human exposure increases. The findings have intensified calls for full ingredient disclosure and a shift toward non-chemical land management strategies that do not rely on persistent synthetic toxins. [2][1]