US EPA opens public comment period for proposed dicamba herbicide from Syngenta

The U.S. Environmental Protection Agency (EPA) has received an application from Syngenta for a new product containing the currently registered active ingredients dicamba and S-metolachlor. The product proposal includes over the top application on both dicamba-tolerant cotton and soybeans. Because the application involves a new use pattern for dicamba, the Agency is providing a 30-day public comment period on the registration application consistent with the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). EPA is also seeking comment on the associated draft labeling that Syngenta submitted, which is available in the docket.

Syngenta’s proposed label would allow application to dicamba-tolerant soybeans before, during, and immediately after planting, and over-the-top of the soybean plant through the ‘V2’ growth stage (where the second set of three leaves of the plant are fully unfolded), but no later than June 12 of each year. Application to dicamba-tolerant cotton in this Syngenta proposal would be allowed before, during, and immediately after planting, and over the top of the cotton plant through the 6-leaf growth stage, but no later than July 30 of each year. Please review Syngenta’s proposed label for additional details.

Like all opportunities for public comment associated with notices of receipt of applications, this action should not be interpreted as a registrant proposal that has been endorsed for future approval by EPA. Should EPA determine that this or any other registrant-submitted application including over-the-top dicamba meets the standard for registration of a new use under FIFRA, EPA will provide a separate opportunity for public comment on the proposed decision at a future time.

To read more about the registration application proposed by Syngenta and submit a comment, see docket EPA-HQ-OPP-2024-0154 on Regulations.gov. The public comment period will close on August 22, 2024, 30 days after the publication date in the Federal Register. EPA will review public comments as part of the proposed application process and incorporate any feedback into the registration decision.

Background

Dicamba is an herbicide registered for use at specified stages in agricultural crop fields of corn, cotton, sorghum, soybeans, sugarcane, and other crops. It was first registered for over-the-top uses on dicamba-tolerant cotton and soybeans in 2016. In 2017 and again in 2018, EPA amended the registrations of all over-the-top dicamba products following reports that growers had experienced crop damage and economic losses resulting from the off-site movement of dicamba. The U.S. Court of Appeals for the Ninth Circuit vacated the 2018 registrations in June 2020 on the basis that ″EPA substantially understated risks that it acknowledged and failed entirely to acknowledge other risks.″ Days after the court’s decision, EPA issued an order for the affected products that addressed existing stocks.

In October 2020, EPA issued new registrations for two dicamba products and extended the registration of an additional dicamba product until 2025. All three registrations included new measures that the Agency expected to prevent off-target movement and damage to non-target crops and other plants. Further state-specific amendments to the registrations occurred in 2022 and 2023.

In response to a lawsuit against EPA concerning these registrations, on February 6, 2024, a ruling by the U.S. District Court of Arizona vacated the 2020 registrations for over-the-top dicamba products XtendiMax, Engenia, and Tavium. EPA issued an Existing Stocks Order (pdf) (655.3 KB) on February 14, 2024 (later revised on March 12), to allow for limited sale and distribution of dicamba over-the-top products that were already in the possession of growers or in the channels of trade and outside the control of pesticide companies. The order also prohibits the use of these dicamba products except where the use is consistent with the previously approved labeling, which included measures intended to reduce environmental damage caused by offsite movement of the pesticide.

For further information, visit EPA’s page on Registration of Dicamba for Use on Dicamba-Tolerant Crops.