On July 24, 2024, Environmental Health Perspectives (EHP) published a study relating to the presence of per- and polyfluoroalkyl substances (PFAS) in pesticide products. PFAS are a class of manmade chemicals used for decades in industrial/consumer products because of properties like resistance to heat, fire, stains, and water. PFAS have been linked to serious health concerns, such as cancer, and have been detected in water, soil, air, food, household and workplace materials, and human blood across the world.

The study concludes that nearly 25% of all U.S. pesticide active ingredients are organofluorines (organic compounds that contain a carbon–fluorine bond) and 14% are PFAS. PFAS are a type of organofluorine or fluorinated molecule. For “active” ingredients approved by EPA within the last 10 years, the study finds that 61% are organofluorines and 30% are PFAS. For “inert” pesticide ingredients approved by EPA, the study finds a seemingly limited presence of PFAS but notes there is a significant lack of information on this issue. Furthermore, the study finds that leaching of PFAS from fluorinated containers into pesticide products is a significant contributor to the presence of PFAS in pesticides. Study, p. 1.

In light of the foregoing, the authors of the study make several recommendations, including: (1) more stringent government agency risk assessment for fluorinated pesticides; (2) transparent disclosure of inert ingredients on pesticide labels; (3) a phase-out of post-mold fluorination of plastic containers; and (4) environmental monitoring and biomonitoring of all PFAS pesticides to gather timely data on their bioaccumulation and potential impact on human and ecosystem health. Id.

The Study’s Findings

The authors state they designed their study to analyze the various ways pesticide products can include PFAS, the extent of PFAS contamination in pesticide products, and the associated implications of PFAS in pesticide products on human health and the environment. Id. at p. 2.

The authors studied 471 unique and conventional active ingredients for pesticides registered by EPA and found that 23% of these ingredients are organofluorines and 14% meet the Organisation for Economic Cooperation and Development’s (OECD) definition for PFAS. OECD defines PFAS as “fluorinated substances that contain at least one fully fluorinated methyl or methylene carbon atom (without any H/Cl/Br/I atom attached to it).” A New OECD Definition for PFAS. This definition includes almost any chemical with at least one perfluorinated methyl or perfluorinated methylene group. The authors also studied 54 conventional active ingredients approved in the last 10 years, finding that 61% of these ingredients are organofluorines and 30% meet OECD’s definition of PFAS. Study, p. 3.

Through a public records request to EPA, the authors of the study learned that EPA previously identified 24 approved inert ingredients as PFAS or suspected PFAS. The authors found that EPA cancelled 12 of these ingredient approvals and that one ingredient did not have any carbon-fluorine bonds, concluding that 11 currently approved inert pesticide ingredients contain organofluorines. Of these 11 organofluorine inert ingredients, the authors found that 8 meet the OECD definition of PFAS. Id. at p. 4.

The study also analyzes the presence of PFAS in pesticides through leaching from fluorinated high-density polyethylene (HDPE) containers. The study notes that EPA found that fluorinated HDPE containers can leach perfluorinated carboxylic acids (PFCAs), a subset of PFAS, into pesticides stored in such containers. The authors conclude that roughly 20% to 30% of all hard plastic containers used in the agricultural sector are fluorinated. Id. at p. 6.

The authors also studied the consequences of PFAS in pesticides, finding that: (1) negative impacts to the immune system is one of the most significant adverse effects to humans from PFAS exposure; (2) PFAS is highly stable in the environment and will persist in the environment essentially forever; (3) PFAS active ingredients are present throughout the country in streams, lakes, and rivers; and (4) PFAS active ingredients can contaminate drinking water. Id. at pp. 6-10.

The Study’s Recommendations

In light of its findings, the study recommends the following:

1. The practice of post-mold fluorination of plastic containers should be discontinued and substituted with other options that do not use fluorine or an in-mold fluorination process found not to produce PFAS;

• The U.S. and other countries should require disclosure of all pesticide ingredients on pesticide labels and safety data sheets (SDSs);

• EPA should issue a data call-in for any pesticide ingredients that do not have immunotoxicity studies;

• All PFAS pesticides should be evaluated for environmental persistence, and the most persistent PFAS pesticides should be mitigated/replaced;

• The U.S. should expand environmental monitoring and biomonitoring programs to include all PFAS pesticides;

• EPA should assess the cumulative impacts from fluorinated degradants common to active ingredients and how fluorinated pesticides can impact total fluorine in the environment and food. Id. at p. 10.

This study highlights the growing public awareness and concern regarding the presence of PFAS in pesticide products and the associated impacts to human health and the environment. For further information regarding PFAS in pesticides, contact a member of Taft’s Environmental group.