The U.S. Environmental Protection Agency (EPA) has renewed its approval for the herbicide paraquat. Paraquat, commonly sold under the brand name Gramoxone by Syngenta, has been the subject of recent legal controversy for its alleged connection to Parkinson’s disease. 

Paraquat was first manufactured in 1961 and rapidly became one of the most common herbicides in the world. The U.S. Center for Disease Control and Prevention calls paraquat “highly poisonous” and the EPA has classified paraquat as a restricted use herbicide. Restricted use herbicides can only be purchased or used by licensed applicators.

In the press statement confirming their decision to renew paraquat’s approval, the EPA included a number of new limitations on the way paraquat could be applied. Those limitations included:

  • Limiting aerial applications and requiring 50- to 75-foot buffer zones around houses.
  • Prohibiting the use of pressurized handguns and backpack sprayers in applications.
  • Requiring enclosed cabs or respirators for users applying via groundboom.
  • Increasing the time after application that the area cannot be accessed, also known as the Restricted Entry Interval (REI) for several crops.

The EPA called these new restrictions “necessary to address the risks identified from paraquat exposure while allowing for the continued use of this important agricultural tool.”

There has been some pushback to the EPA’s renewal of paraquat. The Center for Biological Diversity told, “Not only are we reapproving paraquat when the rest of the world is banning it, but we’re using more of it than ever before.” The center also said paraquat was harmful to small mammals and birds in addition to potential human risks. 

The EPA responded to allegations of a connection between paraquat and Parkinson’s. In their press statement, they said, “EPA evaluated hundreds of studies, including published toxicity and epidemiology literature on paraquat exposure and adverse health outcomes, including Parkinson’s disease.” 

After reviewing these studies, the EPA stated it “has not found a clear link between paraquat exposure from labeled uses and adverse health outcomes such as Parkinson’s disease and cancer.”