Judge Invalidates Wildlife Agency's Malathion Ruling Over Flawed Data

A federal judge struck down a wildlife agency finding that malathion posed no threat to endangered species due to faulty data.

U.S. District Judge Jacqueline Scott Corley on May 13 invalidated the Fish and Wildlife Service's 2022 biological opinion declaring that malathion, a widely used organophosphate pesticide, posed no danger to the nation's roughly 1,800 endangered species. The court found the federal assessment relied on flawed and outdated datasets.

• The 2022 opinion reversed a 2017 draft that found malathion would jeopardize more than 1,200 species, after the EPA updated pesticide label restrictions and claimed new conservation safeguards.
• Yet, Judge Corley highlighted that the Service's estimates for where species live were "arbitrary" and lacked transparent methodology.
• Critical usage data was based on nearly decade-old commercial surveys from Kynetec and state agricultural agencies, which, the agency admitted, were created for market research rather than environmental protection and were not reliable at the state level.

Environmental advocates hailed the ruling, with Lori Ann Burd of the Center for Biological Diversity saying it "is a much-needed course correction for the Fish and Wildlife Service, which submitted to the pesticide industry's demands." George Kimbrell of the Center for Food Safety called it "a vital victory for thousands of endangered species at risk from toxic pesticides" including key pollinators.

The ruling underscores gaps in federal analysis under the Endangered Species Act, spotlighting regulatory uncertainty for entities reliant on malathion and other pesticides. Environmental groups argue that more rigorous, transparent science in agency assessments is needed going forward.