U.S. EPA Launches Fresh Safety Review of Widely Used but Highly Toxic Weed Killer

The EPA has launched a safety investigation of paraquat, a strong weed herbicide used on American fields but banned in over 70 countries. The decision renews federal review of a chemical lambasted by environmentalists, farmworkers, and lawmakers for its severe toxicity and health hazards.

EPA Administrator Lee Zeldin said manufacturers must give updated, real-world scientific research showing paraquat is safe under current settings. The EPA says this evaluation is prompted by new scientific questions and its duty to guarantee that pesticides sold in the U.S. satisfy the highest safety requirements for workers, communities, and the environment.

Paraquat has been used in agriculture since the 1960s to eradicate weeds immediately before planting. Although efficient, it is one of the most toxic herbicides permitted in the US. Federal warnings suggest that swallowing even a little amount can be fatal and that direct touch can cause severe skin and eye problems.

Paraquat was reapproved by the EPA in 2021 following a 15-year pesticide review despite its hazards. Environmental and farmworker groups sued the government for failing to fully account for the chemical’s health dangers. The current assessment began when the EPA asked more time from the courts to analyze health risks in response to legal pressure.

How paraquat behaves after field spraying is being studied. The EPA said new research has raised questions about how much of the chemical can evaporate into the air, exposing humans through breathing or skin contact. Manufacturers must perform paraquat vapor tests in real-world farming circumstances to remedy this. Health effects of inhalation exposure will be examined by the agency.

The EPA says this assessment is not about whether paraquat causes Parkinson’s disease, a neurological ailment that develops over time. The EPA says there is no clear evidence linking paraquat exposure to Parkinson’s, despite thousands of complaints against Syngenta. Syngenta claims the product is safe when used as directed.

The EPA will evaluate two safety factors in addition to human health hazards. Paraquat will be tested for its effects on endangered animals and human hormones. Federal authorities have stated that the agency will take stronger regulatory action if additional studies indicate larger hazards. That could mean stricter usage standards, worker protections, or chemical application restrictions.

The review is renewed amid political pressure. Over 50 Democratic legislators recently pushed the EPA to ban paraquat, calling it a toxic drug with major health and environmental effects. The government has also been criticized for its pesticide rules in recent months, highlighting the ongoing debate over chemical safety in U.S. agriculture and public health.

EPA executives said the reconsideration is based on science and transparency. The purpose is to support regulatory decisions with the most accurate and current data, not to predetermine an outcome, officials say. The review agency has stated that protecting public health, farmworkers, and rural communities will be prioritized, even if additional rules disrupt agricultural methods.

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