EPA Documents Reveal Bayer Selected Its Own Dicamba Restrictions
Internal EPA documents show the agency allowed pesticide manufacturer Bayer to choose specific regulatory mitigation options for dicamba, a decision that has sparked criticism from environmental groups and legal challenges.
Newly released internal documents from the Environmental Protection Agency (EPA) reveal that the agency permitted Bayer to select specific regulatory mitigation options for the controversial weedkiller dicamba. This process effectively allowed the chemical giant to choose its own restrictions regarding volatility and runoff controls.
The documents detail a meeting in May 2025 where the EPA presented Bayer with choices on how to limit dicamba’s potential to drift or wash into waterways. For volatility controls, the agency offered two options: preventing applications when temperatures exceeded 85°F, or allowing applications up to 95°F if the treated acreage was reduced. Bayer selected the less restrictive option, permitting use up to 95°F with reduced acreage. Additionally, Bayer requested an extra provision allowing full-field treatments at higher temperatures if the product was not tank-mixed. The EPA granted both of these requests.
Regarding runoff controls, Bayer chose a middle-tier option from three available levels of protection. The EPA incorporated these selections into proposed federal rules months after the meeting.
This approach has drawn sharp criticism from environmental organizations, including the Center for Biological Diversity and the Center for Food Safety, which are currently litigating against the EPA. Nathan Donley of the Center for Biological Diversity stated that allowing Bayer to choose its preferred measures "crosses a line" and constitutes self-regulation. Critics argue that this undermines public health protections despite dicamba’s history of causing widespread agricultural damage.
Since its first approval in 2016, dicamba drift has damaged millions of acres of farmland, orchards, vegetable farms, home gardens, native plants, trees, and wildlife refuges across the United States. Health concerns linked to dicamba exposure include liver cancer and Non-Hodgkin lymphoma. Experts have described the damage caused by dicamba drift as the worst in U.S. agriculture history, yet lawsuit allegations suggest the current approval provides fewer protections than past approvals.
An EPA spokesperson defended the process, stating that it represents the regulatory system working as intended and asserting that registrants do not dictate terms. However, critics point to broader concerns about regulatory capture within the agency. Notably, the top four positions in the EPA’s toxics office are held by former chemical industry leaders, including Kyle Kunkler, a former pesticide industry lobbyist. Other individuals mentioned in connection with the agency's leadership or related contexts include Nancy Beck and Kelly Ryerson.