The Ninth Circuit Court of Appeals ordered the U.S. Environmental Protection Agency to decide by mid-July whether to ban chlorpyrifos, a widely used pesticide for corn, soybeans, fruit and nut trees, Brussels sprouts, cranberries, broccoli and cauliflower as well as other row crops.

In March 2017, EPA denied a petition that asked it to revoke all pesticide tolerances (maximum residue levels in food) for chlorpyrifos and cancel all chlorpyrifos registrations. The agency concluded that, despite several years of study, the science addressing neurodevelopmental effects remains unresolved and that further evaluation of the science during the remaining time for completion of registration review is warranted. As a part of the ongoing registration review, EPA said it will continue to review the science addressing the neurodevelopmental effects of chlorpyrifos.

On Aug. 9, 2018, the U.S. Ninth Circuit Court of Appeals ordered EPA to ban chlorpyrifos within 60 days. The following month, the U.S. Department of Justice asked the Ninth Circuit to reconsider its opinion.

Agricultural groups have been supportive of EPA’s attempts to block the ban. Writing in support of EPA’s action to deny the chlorpyrifos ban, the American Seed Trade Assn. (ASTA) said: “As a seed treatment, it is used by seed producers and also vegetable farmers and is particularly effective and necessary in situations where there is significant pest pressure. As no- or reduced-till production systems have become more prevalent due to their soil benefits, the corresponding insect pressures have also increased. However, there are only a few products registered for use as seed treatment insecticides. Seed producers and farmers base their seed treatment decisions on historical pest pressure as part of their integrated pest management programs. Without the ability to use chlorpyrifos, entire production fields could be lost. Due to the high value of vegetable seed, this would cause significant economic damage. Chlorpyrifos seed treatments are a cost-effective way to minimize and target the insecticide application in comparison to foliar and soil applications.”

Related:Full Ninth Circuit to rehear chlorpyrifos case

In comments to EPA, organizations representing tens of thousands of American farmers and others who depend upon chlorpyrifos for pest management, said they were deeply concerned about the Ninth Circuit's decision ordering EPA to revoke tolerances and registrations for this critical pesticide. “This decision is unprecedented; no court has previously ordered EPA both to cancel uses and revoke tolerances for a pesticide. Its significance goes beyond just chlorpyrifos and threatens the established regulatory process for all crop protection tools,” the coalition of agricultural organizations said in August 2018 ahead of the rehearing. “For many invasive pests, growers face limited or no viable alternatives, and when an outbreak of a new pest occurs, users look to chlorpyrifos as a proven first line of defense.”

However, environmental groups have continued to call for the ban on the pesticide.

“We commend the court for this ruling as it forces the EPA to stop stalling,” Earthjustice attorney Patti Goldman said. “While we are moving forward, the tragedy is that children are being exposed to chlorpyrifos, a pesticide science has long shown is unsafe. We hope ... EPA finally decides to protect the future of countless children and the health of millions of farm workers.”