Charles Smith, Division Director
Registration Division
Office of Pesticide Programs
Environmental Protection Agency
1200 Pennsylvania Avenue, NW,
Washington, DC 20460

Submitted via regulations.gov

RE: Docket ID No. EPA-HQ-OPP-2022-0003

Dear Director Smith,

Toxic Free North Carolina, joined by the __ undersigned organizations and individuals, submits this comment in opposition to the registration of cyclobutrifluram. Our opposition to this proposed active ingredient is based on the demonstrated potential for persistence and contamination in the environment over time. We are concerned about cyclobutrifluram’s persistence in the environment and potential to impact drinking water and groundwater due to the chemical structure of this pesticide and intended use with broadcast applications or soil drenching.

High persistence in the environment
In the drinking water assessment for this proposed active ingredient, EPA finds cyclobutrifluram to be “persistent in soil and water” with half-lives ranging from 6 months to 3 years. Cyclobutrifluram is intended to be “applied as a foliar spray on turf, soil drench, broadcast, and chemigation for ornamentals, soil drench for romaine lettuce, and seed treatment for cotton and soybean". With the extended half life and intended application methods, we see potential for high persistence in the environment for this proposed active ingredient. Our agricultural communities already face a multitude of groundwater contaminants and emerging concerns. Approving cyclobutrifluram could worsen water quality especially if used in high amounts and year after year.

Cyclobutrifluram is a PFAS
Based on the widely used definition of per- and polyfluoroalkyl substances (PFAS) from the Organisation for Economic Co-operation and Development (OECD), the proposed active ingredient cyclobutrifluram is a PFAS. The OECD definition was co-authored by scientists at the U.S. EPA and 37 other nations. This definition of PFAS is currently used by some offices at the EPA, the European Chemical Association, Congress, the Department of Defense, and is already codified into law by 23 states. Research and regulatory actions from the EPA on PFAS in recent years have demonstrated the environmental and health risks posed by the “forever chemical” compounds as a class.

Reliance on PFAS pesticide active ingredients poses negative environmental and health risks, including potential impacts to immune response, water contamination, and degradation into compounds that do not reduce the harm. EPA’s analysis of cyclobutrifluram notes that degradation of the proposed active ingredient into trifluoroacetic acid (TFA) was found to be one of the major degradates. TFA is increasingly identified as a global concern and an irreversible threat. We caution against the downplaying of risk from degradation of cyclobutrifluram in the environment.

The potential for increased health harms related to PFAS compounds calls for caution in approving any additional compounds like cyclobutrifluram. PFAS exposure has been associated with elevated cholesterol, liver dysfunction, weight gain, ulcerative colitis, reproductive problems, impacts to pregnancy, thyroid disease and dysfunction, and kidney cancer. Analysis of the toxicity endpoint for cyclobutrifluram found impacts to the thyroid the most sensitive. A 2024 meta-analysis found association between long- and short-chain PFAS compounds and thyroid-related health outcomes.

Recommendation not to approve cyclobutrifluram
We write to caution against the approval of this active ingredient and any additional pesticides that are classified as PFAS “forever chemicals” based on the reasons outlined above. Before approving any additional PFAS pesticides, the agency must review the impact of existing PFAS pesticides in full, including their degradates, and assess the compounds in a cumulative way to accurately measure the risks posed to the environment and public health.

A 15 day comment period is insufficient to fully assess all potential severe and lasting impacts of this proposed active ingredient on the environment and our health; however, our analysis of the provided assessment of cyclobutrifluram leaves us concerned about the demonstrated and omitted environmental and health impacts. If approved, this pesticide would contribute to the growing problem of PFAS contamination in communities across the nation. We urge the agency to begin thoroughly addressing the existing problem of PFAS active ingredients used in agriculture and continue the work of addressing PFAS in our environment.

We respectfully request EPA to deny the registration application for the PFAS pesticide active ingredient cyclobutrifluram.

Sincerely,

Kendall Wimberley
Policy Manager
Toxic Free North Carolina

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