Senior leaders in the Environmental Protection Agency’s Office of Chemical Safety and Pollution Prevention altered or omitted key evidence in approving dicamba for use in 2018, leading to a federal appeal court’s vacating of the registrations, according to the agency's internal watchdog. 

In a report issued Monday, the agency's Office of Inspector General, recommended measures to strengthen compliance with EPA’s scientific integrity policy. EPA’s OCSPP agreed largely with the recommendations, but in one case proposed an alternative way to implement it.

The herbicide has been blamed for damaging millions of acres of soybeans and other vegetation because of spray drift and volatilization. In October, EPA approved new dicamba registrations for five years.

An EPA spokesperson Monday said the agency stands by its 2020 dicamba decision "made with the input of career scientists and managers."

"Scientific integrity is a priority for the Biden-Harris Administration," EPA said. "Under Administrator [Michael] Regan’s leadership, EPA has a renewed commitment to protecting human health and the environment by following science and making evidence-based decisions that rely on the input of career scientists."

The spokesperson continued: "The political interference that occurred with the 2018 dicamba decision happened despite the best efforts of EPA’s career scientists and managers to recommend a different approach. The agency has responded to the Office of the Inspector General’s report and is implementing several actions to ensure that our pesticide registration decisions are free from political interference and that the agency’s scientific integrity policy is upheld. The agency looks forward to productive conversations with the Office of the Inspector General as we work to resolve this matter."

As noted in the report, the nominee to lead OCSPP, now-principal deputy administrator Michal Freedhoff, sent a memo to OCSPP staff in March citing the dicamba decisions as a case where “political interference sometimes compromised the integrity of our science,” which “contributed to a court’s vacating [the dicamba] registrations” held by Bayer, Corteva and BASF.

Freedhoff did not cite the 2020 dicamba registration decisions as having similar problems, and the OIG report said that unlike in the 2018 process, EPA career scientists signed off on 2016 and 2020 documents supporting dicamba registrations.

But in 2018, OIG said, citing a scientist in the Office of Pesticide Programs (OPP), “OCSPP senior management provided direction to use registrants’ data for reported dicamba damages instead of OPP divisional data sources. In its ruling to vacate the dicamba registrations, the Ninth Circuit Court [of Appeals] found the dicamba damages to be substantially understated. Divisional scientists told us their original source data would have addressed the court’s concerns.”

In addition, “multiple scientists … reported, and emails confirmed, that after OCSPP senior management review, scientists were provided with an outline from the assistant administrator’s office for rewriting their benefits and impact analysis document,” OIG said. “The outline removed several sections of the original document which the scientists said were relevant based on the analysis they completed.”

In another example, a scientist told OIG that OCSPP senior management and policymakers “decided to use plant height as the standard measure of dicamba effect on plants,” which differed from career scientists’ “recommended approach to use visual signs of plant injury — an approach used in academic and registrant direct-spray toxicity studies, in field studies evaluating off-field movement, and in information reported in state investigations of dicamba damage.”

That direction from senior management “changed the division’s scientific conclusions,” OIG said. In each example, OIG said “scientists reported that changes from senior management did not make sense and seemed to convey a lack of understanding of the data or analyses.”

OPP scientists who were interviewed by OIG “all described feeling constrained or muted in sharing their scientific integrity concerns with senior management during the dicamba registration process,” the report said. “The EPA’s actions on the dicamba registration left the decision legally vulnerable, resulting in the Ninth Circuit Court of Appeals vacating the three 2018 registrations for violating FIFRA by substantially understating some risks and failing to acknowledge others entirely.”

EPA scientists interviewed by OIG “said that senior leaders were more involved in the dicamba decision than in other pesticide registration decisions,” with one saying “[they] never ha[d] this level of front office involvement” in a pesticide registration decision, and that “[they] almost never ha[d] underlying analysis changes, and this is the first exception [this scientist was] aware of.”

In addition, “Multiple scientists said they felt directed to change the science to support a certain decision and that the reasons for senior managers’ requested changes were not documented.”

Interested in more news on farm programs, trade and rural issues? Sign up for a four-week free trial to Agri-Pulse. You’ll receive our content - absolutely free - during the trial period.

In response to an OIG recommendation on making sure any changes to “scientific opinions, analyses, and conclusions” are documented, the Office of Chemical Safety and Pollution Prevention said its “scientific integrity and quality assurance lead(s) will develop Standard Operating Procedures (SOPs) or formal Best Practices on ensuring scientific integrity in pesticide regulatory decisions. These SOPs will ensure that material changes to the risk assessment, risk characterization, and science documents from outside of the authoring OPP Division are clearly documented and communicated by those making the changes.”

OIG also recommended issuance of “an assistant administrator-level verification statement that Scientific Integrity Policy requirements were reviewed and adhered to during the pesticide registration process.”

OCSPP, however, said “the incidents described … reflected a purposeful decision made by the three senior leaders in OCSPP’s immediate office at the time of the 2018 dicamba decision. The incidents did not reflect a failure of OCSPP’s processes or typical practices. OCSPP has no reason to believe that a different ‘verification’ requirement would have caused these individuals to make a different decision.”

The recommendation also would “inject[] senior (political) leaders into the science review process where, currently, most of OCSPP’s typical practices do not include such a role,” OCSPP said. Instead, OCSPP proposed “an alternate Corrective Action that OCSPP believes accomplishes the overarching goal: obliging Assistant Administrator-level leaders to commit to adhere to the Scientific Integrity Policy.”

“The OCSPP Assistant Administrator shall annually issue a memorandum to all OCSPP staff and management to affirm their own and the Office’s commitment to the Scientific Integrity Policy and to establish clear expectations of behavior to uphold scientific integrity,” OCSPP said. OIG called that recommendation “unresolved.”

OCSPP agreed to provide training on its Scientific Integrity Policy as also recommended by the OIG.

According to documents and news reports from the Web, the officials referred to as “senior leadership” in the report are Charlotte Bertrand, the former OCSPP acting principal deputy assistant administrator; Nancy Beck, former OCSPP deputy assistant administrator; and Erik Baptist, former OCSPP deputy assistant administrator for law and policy.

For more news, go to