Court bans use of chlorpyrifos pesticide in U.S.

The below by Stephen Kloosterman, Associate Editor, Vegetable Growers News.

The U.S. Ninth Circuit Court of Appeals in August ordered an EPA ban on the broad-spectrum pesticide chlorpyrifos.

The ban will take away a tool that many growers are still using, and its manufacturer says that additional legal recourse is being considered. But others in the industry say action was overdue and there are softer chemicals and biological controls lined up to take chlorpyrifos’s place as a bug killer.

In a 2-1 decision, a panel of judges held that the EPA was in direct contravention of federal law by allowing the product’s use. The panel also found that “there was no justification for the EPA’s decision in its 2017 order to maintain a tolerance for chlorpyrifos in the face of scientific evidence that its residue on food causes neurodevelopmental damage to children,” according to a court staff’s summary of the majority opinion.

The dissenting judge on the panel, Ferdinand F. Fernandez, was in favor of dismissing the petition because he thought the appeals court didn’t have jurisdiction.

The EPA was ordered to revoke all tolerances of chlorpyrifos and cancel all registrations within 60 days.

In a recent statement, EPA spokesman Michael Abboud said that the agency is reviewing the court decision. He also questioned data from Columbia Center for Children’s Environmental Health regarding the health effects of chlorpyrifos.

“The Columbia Center’s data underlying the court’s assumptions remains inaccessible and has hindered the agency’s ongoing process to fully evaluate the pesticide using the best available, transparent science,” he said.


Chlorpyrifos has been used as a pesticide since 1965. In agriculture it is mostly used in corn, but other crops include soybeans, fruit and nut trees, Brussels sprouts, cranberries, broccoli, and cauliflower, as well as other row crops. Farmers in California used it to treat 640,709 acres in 2016, according to a report from the state’s Department of Pesticide Regulation (DPR). Most recently, it belonged to Corteva Agriscience, the new company being created by spinning off the Agriculture Division of DowDuPont.

Corteva addressed the ruling in written statement:

“Chlorpyrifos is a critical pest management tool used by growers around the world to manage a large number of pests, and regulatory bodies in 79 countries have looked at the science, carefully evaluated the product and its significant benefits and continued to approve its use.

“We note that this was a split decision of the panel and we agree with the dissenting judge’s opinion. We expect that all appellate options to challenge the majority’s decision will be considered. We will continue to support the growers who need this important product.”

The California DPR and companies are now developing chlorpyrifos-free treatment plans.

Yellow mite

“We had a meeting with DPR about two weeks ago (before the ruling) and presented what was shovel-ready, what could be replacements,” said Pam Marrone, CEO and founder of bio-based pest management company, Marrone Bio Innovations. Her company offers two products, Grandevo and Venerate, that use bacteria strains to target certain insects and mites.

On the table are not only non-chemical biological products from smaller manufacturers like Marrone Bio Innovations, but also biological products owned by larger companies and chemical products thought to be less harsh than chlorpyrifos. “It’s not just about ours … there are softer products from DowDuPont and FMC,” she said.

Marrone said that a chlorpyrifos ban has been a long time coming (“It was just a matter of time on that one”). But even she recognizes the steep learning curve that growers now face. In Marrone’s PowerPoint presentation to DPR, she recommended a three-year transition period where integrated pest management plans with biopesticides would be developed and demonstrated on the farm, “so that by the third year, growers are comfortable with incorporating alternatives.”

Marrone called her three-year plan “a soft landing” for growers. She’d like to see similar soft landings for other chemistries likely to be phased out by the U.S. in the years ahead, such as methyl bromide fumigation which is already banned in European Union.

But as things stand, growers face more abrupt transitions. Many of the growers aren’t used to biopesticides.

“They don’t know about them and they don’t know how to use them,” Marrone said. For Marrone, it’s not just about convincing the growers, but also Extension agents from land grant universities across the country who trial new products and advise the growers, she said.

“The land grant Extension specialists are getting better,” she said. It’s going to be more than just us (manufacturers educating growers), but it’s going to take the key influencers to take the plunge, more than they have.”

Reprinted with permission.


Images: Eric Erbe (middle); Keith Weller (bottom), both of the Agricultural Research Service, United States Department of Agriculture