The Environmental Protection Agency has canceled registration of a dozen pesticides, from a class of chemicals known to harm bees.

The cancellations are effective as of May 20 for 12 neonicotinoid-based products produced by Syngenta, Valent, and Bayer.

The Federal Insecticide, Fungicide, and Rodenticide Act requires pesticides sold or distributed in the U.S. to be registered by the EPA.

Under a December settlement agreement linked to an Endangered Species Act challenge by environmental groups, the companies voluntarily agreed to petition EPA to cancel 12 out of 59 products containing the active ingredients clothianidin and thiamethoxam.

Developed as an alternative to organophosphate and carbamate pesticides, neonicotinoids are chemically related to nicotine, and attack the nervous system of insects.

Unlike traditional pesticides, “neonics” are also systemic, meaning that when taken up by the root system, the entire plant becomes toxic to insects.

“Today’s cancellation of these neonicotinoid pesticides is a hard-won battle and landmark step in the right direction,” said George Kimbrell, legal director at the Center for Food Safety, which litigated the case and was a party to the settlement agreement.

Often used as seed coatings on crops such as corn, cotton, and soybeans, in recent years increased use of neonics has been linked to declines of honeybees, wild bees, and other insects.

Impact for Farmers

Among the 12 pesticides canceled in the U.S., seven were for seed coating products used by farmers.

According to Syngenta, any move to further restrict access to neonicotinoids risks harming farmers by removing one of their most widely used insecticides.

“After five years of litigation, this settlement represents a positive outcome in the interest of all parties. The terms clearly support America’s farmers while ensuring continued protection of the environment,” Syngenta said in a statement.

“The settlement allows growers continued access to trusted neonicotinoid products containing thiamethoxam, essential for controlling destructive pests, managing resistance, and supporting integrated pest management.”

While farmers will still have access to other neonic-based products for the time being, environmental groups are pressing EPA for a complete ban on all outdoor uses for neonics in the coming years based on similar endangered species concerns.

“This entire class of active ingredient soon will be up for re-registration [under the Federal Insecticide, Fungicide, and Rodenticide Act] by 2022,” said Kimbrell. “These first 12 were just an interim step.”

In April 2018, the European Union adopted a near total ban on outdoor uses of neonic pesticides.

The restrictions in the EU apply to 3 out of 5 active neonic ingredients, however the applications that remain are for plants who spend their entire life cycle in greenhouses.