Another PFAS-containing pesticide headed for US registration

US regulators are poised to approve a pesticide made with a controversial class of toxic chemicals, stoking concerns of new risks for farms across the country. 

Syngenta, which developed the pesticide and is seeking US Environmental Protection Agency (EPA) approval, lauds the new active ingredient, cyclobutrifluram, as a safe way to battle pests and diseases and help promote “sustainability.”

But environmental and health advocates say the new pesticide product contains fluorinated chemicals, which, by definition, makes them per- and polyfluoroalkyl substances (PFAS), which can persist in the environment for decades or even centuries. 

There are thousands of types of PFAS that have been used for decades around the world, but evolving research has shown that many are linked to health risks such as cancer and immune system problems. Detections of certain PFAS in the soils and products of farms and ranches have forced some out of business. The National Association of State Departments of Agriculture sees PFAS as a “major hazard” to US farmers and ranchers and has called on state and federal agencies to offer financial support and create assistance programs for “this emerging risk.”

“This is a PFAS and if it’s going to be applied that means more PFAS in the environment and communities need to be aware of that, especially with what we’ve seen with water contamination,” said Kendall Wimberley, a policy manager at Toxic Free NC, which has been fighting the registration. Roughly 45% of the country has at least one PFAS compound in their drinking water already, according to federal estimates. 

Syngenta applied to the EPA four years ago to register cyclobutrifluram for use on turf, fruit and nut trees, ornamentals, romaine lettuce and to be applied as a coating to soybean and cotton seeds to target roundworms and pathogens that kill crops.

“This is a PFAS and if it’s going to be applied that means more PFAS in the environment and communities need to be aware of that, especially with what we’ve seen with water contamination.” – Kendall Wimberley, Toxic Free NC

The EPA appears to favor approval despite an agency finding that one of the chemicals cyclobutrifluram breaks down into is trifluoroacetic acid (TFA), which is linked to cancer and reproductive problems with a half-life of 200 years. Cyclobutrifluram is “persistent in soil and water” with a half-life ranging from six months to three years, according to an EPA analysis. A separate EPA assessment of cyclobutrifluram found exposure linked to impacts on thyroids, livers and body weights in animal studies but determined “that registering these products containing cyclobutrifluram … will not cause unreasonable adverse effects on human health or the environment.”  

The public comment period for the registration ends Tuesday, April 6.  

“If we spray this stuff today, half of it will be around for the next presidential election and the half that does break down will be around for the birth of our grandchildren’s grandchildren,”  said Nathan Donley, environmental health science director with the Center for Biological Diversity. “This is just so shortsighted.” 

PFAS are a group of more than 9,000 chemicals and pesticides that have been used in a wide range of consumer and industrial products and processes for many years. The EPA last year moved to designate nine types of PFAS as hazardous substances, and other types of PFAS are under scrutiny. 

PFAS use in pesticides is an area of particular concern, and in 2022, the EPA banned 12 PFAS compounds from pesticides.

Last year, Donley and other scientists reported PFAS make up about 14% of all active ingredients in pesticides used in the US, including nearly one-third of active ingredients approved in the last decade. In addition to the intentional use, the study found PFAS can leach from containers and get into pesticides.

Giving farmers “freedom” 

Syngenta did not respond to requests for comment. However, in a 2020 press release announcing the “Tymirium” technology being used to craft the new cyclobutrifluram products, the company said it can control “both nematodes and soil-borne diseases” and, by protecting roots, will play “a critical part in enabling no-tillage and conservation-tillage practices” that are widely seen as key to protecting and enhancing soil health 

“It will give farmers the freedom to maximize their yields without having to compromise on sustainability,” Jon Parr, president of global crop protection, said in a statement. 

Soybean cyst nematode is seen as a significant threat to farmer profitability, estimated to cost US soybean farmers up to $1.5 billion annually. 

Syngenta has already received approval for the new pesticide in Argentina. 

“Too late” 

The EPA still must consult  with the US Fish and Wildlife Service on the impacts approval of the new pesticide might have on endangered species, but  environmental advocates are bracing for an expected approval. 

“We’re quickly returning to the age of the 1960s and 1970s, when really persistent pesticides, like DDT, were in wide use,” said Donley.  “The legacy of impacts of what the EPA’s currently approving won’t be known for decades. By then it’ll be too late.”

(Featured photo by Getty Images for Unsplash+)