The US Environmental Protection Agency (EPA) handed pesticide giant Bayer the right to select the regulatory framework for its weedkiller dicamba, internal documents obtained by The Guardian demonstrate.

How the EPA Drafted Dicamba Rules

According to the files, EPA officials presented Bayer with a short list of mitigation measures – ranging from buffer‑zone requirements to application‑timing restrictions – and asked the company to choose the option it preferred. The agency then incorporated Bayer’s selection into a proposed federal rule that will be published for public comment.

EPA staff said the approach was intended to speed up rulemaking on a chemical that has sparked a wave of lawsuits from farmers claiming damage from drift. The agency’s own guidance notes that dicamba can travel up to 3 kilometres under windy conditions, contaminating neighbouring fields.

Industry Influence and Environmental Concerns

Environmental groups, including the Natural Resources Defense Council, have called the process “a textbook example of regulatory capture”. They argue that allowing the manufacturer to shape the rule undermines the agency’s statutory duty to protect public health and the environment.

Dicamba, first introduced in the US in 2007, quickly became popular for its ability to control resistant weeds in soybeans and cotton. However, reports of off‑target damage – from defoliated corn to ruined vegetable patches – have mounted. By 2024, more than 2,000 lawsuits had been filed, and several states imposed their own restrictions.EPA’s own scientific review, released in 2025, warned that existing mitigation measures were insufficient to prevent drift‑related harm. Critics say the agency’s decision to let Bayer choose from a limited menu sidestepped those findings.

What Comes Next

The draft rule, which reflects Bayer’s preferred mitigation option, is slated for public comment by the end of October. EPA officials have said a final rule will be issued in early 2027, subject to review by the White House Office of Management and Budget.

Legal experts expect the rule to be challenged in federal court, citing the agency’s apparent deviation from the Administrative Procedure Act. Meanwhile, farmers awaiting clearer guidance remain uncertain, as some have already altered planting schedules to avoid potential penalties.

Congressional oversight committees have announced plans to hold hearings on the EPA‑Bayer interaction, signalling that the episode could shape future pesticide regulation reforms.