The US EPA issued an endangered species protection notice, restricting the use of organophosphorus pesticides such as Chlorpyrifos

The U.S. Environmental Protection Agency (EPA) has announced that it will set specific geographic limits on the use of the pesticides Chlorpyrifos, Diazinon, and Malathion to protect federally threatened or endangered species and their critical habitats, among other measures, by changing pesticide labeling requirements and issuing Endangered species protection proclamations.

Chlorpyrifos, Diazinon, and Malathion are organophosphorus insecticides, which are mainly used in crops, landscaping and forest protection. EPA found, based on a biological assessment, that the current registered use of the three pesticides could adversely affect one or more listed species.

In order to reduce the harm of pesticides to threatened species, EPA, in consultation with the National Marine Fisheries Service (NMFS) and registered companies, issued a "no-harm" biological opinion for the three pesticides. Registered businesses promise to modify product labels and include measures to reduce runoff and drift. The EPA will also issue a notice restricting the use of these pesticides in specific areas.

The notice includes restrictions on application time, dosage, and mixing with other pesticides. The Chlorpyrifos and Diazinon advisories also include wind speed restrictions; The Malathion bulletin requires a buffer zone between the applied area and the habitat. These mitigation measures will not only protect listed species, but will also reduce impacts on non-listed species.

At present, the label of Chlorpyrifos products for non-food use has been approved and updated. EPA requested and received NMFS consent to extend the implementation of the "no harm" biological opinion until August 2024 in order to update the labeling of those food uses.