A new report from a federal watchdog calls the Environmental Protection Agency (EPA) into question over its 2018 decision to register three dicamba herbicides.
The document, released by the Office of the Inspector General on Monday, highlights how the agency under the Trump administration did not follow the usual rules and procedures in this process in the lead-up to making the decision. It notes that the EPA did not undergo peer reviews of scientific documents that were created to inform the decision, and at the time, senior leaders in the Office of Chemical Safety and Pollution Prevention (OCSPP) were largely involved. The report said this led to the omission of scientific documents to address stakeholder risks. It also details how staff felt muzzled in sharing their concerns around dicamba registrations.
“The EPA’s Scientific Integrity Policy affirms that the Agency’s ability to pursue its mission to protect human health and the environment depends upon the integrity of the science on which the EPA relies,” the report says. “We found that the EPA’s 2018 decision to extend registrations for three dicamba pesticide products varied from typical operating procedures.”
The document echoes many of the same points outlined in an internal memo from an EPA staff member that was released in March. The memo explained that registration decisions of dicamba were tainted by political interference under the Trump administration. It stated that such interference compromised the integrity of science and that OCSPP senior leadership directed staff to discount specific studies used to assess risks, benefits and negative impacts.
The initial controversy around dicamba is grounded in reports that it can be particularly destructive when it vaporizes and travels miles away from its initial application site. It’s reportedly caused severe damage to forests and crops that are not genetically altered to be resistant to the herbicide. This phenomenon, known as “dicamba drift,” has incited legal battles with environmental groups and caused several states to issue preliminary bans on dicamba. There was also a 2020 appeals court ruling, which prohibited the use of three products containing dicamba—the very ones the EPA registered in 2018. Despite this, the EPA extended its registration later that year for one dicamba product and announced a decision to register two end-use products “for applications only on dicamba-tolerant cotton and dicamba-tolerant soybeans.”
Products of the latest registration decision will expire in December 2025, unless EPA decides to amend. Although it is not clear what the new report means for the future of dicamba, it outlines three recommendations for corrective action. This includes a proposal that would require senior managers, who make changes to scientific documents, provide reasons for such changes. It recommends that there be a verification statement issued for all decisions, saying that scientific integrity policy requirements were reviewed and followed. Lastly the report recommends there be annual training for all staff to affirm the office’s commitment to its scientific integrity policy.
The report indicates that recommendations one and three are resolved and “pending.” The second proposal is still unresolved.