Ninth Circuit Invalidates EPA Approval of Controversial Pesticide

In a major victory for beekeepers, the U.S. Court of Appeals for the Ninth Circuit has vacated the EPA’s approval of the pesticide sulfoxaflor, concluding that the approval was based on “flawed and limited data” regarding adverse impacts on honey bee populations. Pollinator Stewardship Council v. United States Environmental Protection Agency, No. 13-722346 (Ninth Cir., Sept. 10, 2015).

Background of Sulfoxaflor Approval

Dow AgroSciences applied to the EPA for approval of sulfoxaflor, part of a subclass of neonicotinoids that kill insects by interfering with their central nervous systems. Like other neonicotinoids, sulfoxaflor is a systemic insecticide that is absorbed and distributed throughout the plant’s vascular system into tissues, pollen and nectar. Some studies have linked use of neonicotinoids to Colony Collapse Disorder and associated rapid declines in bee populations, and use of certain classes of neonicotinoids has been restricted in Europe based on concerns about impacts on bees.

Dow asked the EPA to approve sulfoxaflor for use on a variety of crops, including citrus, cotton, fruiting vegetables and wheat. As part of its application, Dow submitted a number of studies concerning the potential impact of sulfoxaflor on bees and bee colonies, both from direct contact and through consumption of nectar and pollen containing the chemical. Based on the studies, the EPA classified sulfoxaflor as “extremely toxic” to honey bees. It also determined that some of the studies were not conclusive and/or potentially understated impacts on the bee population and requested additional studies. Pending receipt of such studies, the EPA proposed to conditionally approve use of sulfoxaflor, at concentrations much lower than those proposed by Dow, with certain mitigation measures, including restrictions on use during blooming seasons.

Less than seven months later, however, the EPA reversed course and decided to unconditionally approve sulfoxaflor. Although the studies the EPA had requested had not been completed, the agency concluded that potential hazards to bees from exposure to the chemical would be appropriately mitigated by “reduced application rates, increased minimum application intervals, and pollinator-related labeling mitigation.” One of the mitigation measures required the product label to contain the statement that “[n]otifying known beekeepers within 1 mile of the treatment area 48 hours before the product is applied will allow them to take additional steps to protect their bees.”

The Ninth Circuit’s Analysis

Following a thorough examination of the EPA’s process and the scientific evidence relied on for the approval, the Ninth Circuit held that the agency’s decision to issue unconditional approval was unsupported by substantial evidence. The EPA had clearly recognized, the court observed, that the studies conducted by Dow did not provide sufficient data to make an informed decision regarding potential effects of sulfoxaflor on honey bees.

Several of the studies, for example, assumed sulfoxaflor application rates much lower than the rate proposed by the EPA; other studies did not conform to the guidance specified by the agency. Moreover, all of the studies, according to the court, contained “inconclusive or insufficient data on the effects of sulfoxaflor on brood development and long-term colony health.” It was on the basis of these deficiencies that the EPA decided to grant only conditional approval pending additional studies. Because, “by the EPA’s own reckoning” the data were insufficient to evaluate the effects of use of the chemical at the application rate specified by the EPA, the agency’s unconditional approval lacked substantial evidence. “[T]he EPA has no real idea,” the court concluded, “whether sulfoxaflor will cause unreasonable adverse effects on bees.”

The EPA also maintained that some of the secondary studies, although concededly incomplete, had been conducted only because a small number of the chemical residue measurements had been high enough to trigger the “acute level” of concern. Because the threshold for this “inherently conservative” trigger had been exceeded in only a small fraction of the measurements, the EPA argued, the flaws in the secondary studies should not have precluded approval of the pesticide. This argument “does not fly,” the court said. Having adopted regulations requiring secondary studies based on specific thresholds, the EPA was not free to ignore the approved standards because only a few of the measurements had exceeded the threshold by a small amount. While this argument might be “well taken as a practical matter,” the court noted, it was “irrelevant as a legal matter.”

In light of “the precariousness of bee populations” and the uncertainties regarding the risks posed by use of sulfoxaflor, the court vacated the EPA’s approval in its entirety pending adequate studies and data regarding the effects of sulfoxaflor on bees in compliance with EPA regulations.