By MATEUSZ PERKOWSKI
Government biologists must rethink a scientific finding that several common pesticides jeopardize protected fish species, according to a federal appeals court.
The National Marine Fisheries Service’s conclusion was “arbitrary and capricious” because it relied on evidence that wasn’t always “logical, obvious or even rational,” the 4th U.S. Circuit Court of Appeals ruled on Feb. 21.
The agency issued its finding in 2008 after a protracted fight with environmentalists, resulting in spray restrictions on chlorpyrifos, diazinon and malathion.
The biological opinion recommended that the U.S. Environmental Protection Agency require spray buffers of 500 to 1,000 feet around waterways to prevent the chemicals from harming salmon and steelhead species along the West Coast.
Several pesticide manufacturers — Dow AgroSciences, Makhteshim Agan and Cheminova — challenged that “biological opinion,” claiming that it was based on faulty analysis and conclusions.
The 4th Circuit has now granted their request to overturn the biological opinion, finding it “was not the product of reasoned decision-making” and must be reconsidered by NMFS.
The three-judge panel based its decision on three main problems with the study:
• Agency scientists assumed that juvenile fish would be exposed to each of the three pesticides at toxic levels for four days straight without properly explaining why it applied this standard.
The assumption was criticized by the EPA because it’s a common laboratory test that doesn’t correlate with actual pesticide levels in streams, and even NMFS admitted the measure wasn’t ideal.
“But acknowledging a model’s limitations does not go to explaining why it was chosen and the rationality of its relationship to real-world conditions,” the ruling said.
• The study used data collected by the U.S. Geological Survey between 1992 and 2006 that uncovered high levels of the chemicals in waterways, but the manufacturers claimed this information was outdated.
The EPA told the agency’s biologists that the data preceded major restrictions intended to mitigate pesticide concentrations in streams, but NMFS persisted in using the old information.
“The Fisheries Service recognized that it was relying on outdated data and that it had been presented with more recent data, but it chose to continue relying on the outdated data without explaining why,” the 4th Circuit said.
• To avoid jeopardizing the existence of the fish populations, NMFS said that spraying the pesticides should be prohibited within 500 feet of waterways if applied on the ground and 1,000 feet if applied from the air.
Pesticide manufacturers complained that this was an overly rigid approach, since it didn’t consider the stream’s depth or width. The agency countered that that the restriction was justified and that it wasn’t required to consider alternatives, regardless of economic impacts.
The 4th Circuit disagreed with the government, ruling that “such a broad prohibition readily calls for some analysis of its economic and technical feasibility.”