Dicamba report casts new doubt on weedkiller’s future

Farmers, lawyers and scientists said the future of the weedkiller dicamba now faces fresh uncertainty after a U.S. Environmental Protection Agency report revealed senior Trump-era staffers improperly influenced the decision to re-approve the herbicide in 2018.

The report, released Monday, does more than sow distrust, several said. It undermines the credibility of federal regulators, discourages the participation of outside scientists, encourages lawyers to mount new arguments, and could push farmers to reconsider their crop decisions.

“The report begs to have further investigation done into it,” said Paul Lesko, a St. Louis-based lawyer working on a wave of dicamba cases.

New clients continually are telling him of damage done to their fields by dicamba, he said.

German conglomerate Bayer, a major manufacturer of the chemical, said it stands by its widely adopted XtendiMax line of dicamba products.

“We have continued to test and build on the robust scientific data behind this important technology,” the company said on Monday. “And the latest EPA decision in 2020 was based on a significant amount of new data and learnings from recent seasons.”

Dicamba, a decades-old chemical, rose to newfound popularity in recent years. Weeds were developing resistance to former herbicide staples, such as Roundup, pioneered by Creve Coeur, Mo.-based Monsanto. Monsanto, looking for alternatives, engineered crop varieties that could withstand dicamba sprayed over them.

Bayer purchased Monsanto in 2018.

But farmers soon began to complain dicamba vaporized and drifted to other fields, harming other plants and crops.

Millions of acres of crop damage have now been reported across U.S. farms — including a $265 million jury ruling last year against Bayer and competitor BASF in favor of a Missouri peach farmer — all fueling heated controversy and tearing a rift in the agricultural community.

On Monday, the EPA’s Office of Inspector General released a report describing a range of procedural inconsistencies that led up to the decision to uphold the product’s availability in 2018.

“This led to senior-level changes to or omissions from scientific documents,” the report said.

“For instance, these documents excluded some conclusions initially assessed by staff scientists to address stakeholder risks. We also found that staff felt constrained or muted in sharing their concerns on the dicamba registrations.”

Academic weed scientists said it undermines the credibility of the regulatory process that governs herbicides such as dicamba, and discourages participation from experts.

“There were a lot of people in the academic community that were disappointed with the decision-making in 2018,” said Andrew Thostenson, a pesticide specialist for North Dakota State University’s extension service. “That raised some level of cynicism with EPA. It’s like, ‘Why should I bother providing you with this stuff if you’re not going to follow through?’”

And the EPA was under a lot of pressure to re-approve dicamba in 2020, Thostenson added, noting the decision was issued in the week before the presidential election.