Malathion, an organophosphate insecticide and a potential neurotoxin, is widely used for pest control including suppression of insects that affect poultry. It is estimated that 2.7 million pounds of malathion is applied annually in the U.S. A coalition of environmental activists including the Center for Biological Diversity, Center for Food Safety and Pesticide Action Network North America recently filed a lawsuit against the U.S. Fish and Wildlife Service claiming the agency is in violation of the Endangered Species Act.  In 2017, scientists within the U.S. Fish and Wildlife Service produced a report confirming that unrestricted use of malathion would be detrimental to at least 500 threatened and endangered species that are dependent on insect pollination.  During the previous Administration, the findings and recommendations made by scientists were reversed by the then Secretary of the Interior. This essentially moved the goal posts by altering the criteria to assess any potential detrimental effects of pesticides.

The Fish and Wildlife Service under the present Administration prepared a revised 2022 opinion on malathion concluding that continued use of the insecticide would not affect any protected species of wildlife or plant.  The opinion did, however, suggest restrictions on spraying malathion.  Mosquito vectors have emerged as a cause of an increased incidence of arboviral infections including West Nile disease, equine encephalitis and dengue fever.

The poultry industry needs malathion, and application within houses should not represent a problem to the environment. It is hoped that as with the case of rodenticides that there will be no outright bans allowing regulated use by trained applicators.