Acting under terms of a lawsuit brought by anti-pesticide groups and salmon fishermen, NOAA Fisheries Service issued findings under the Endangered Species Act that chemicals malathion, diazinon and chlorpyrifos jeopardize the survival of all 28 species of Pacific salmon listed as threatened or endangered in the West.
"These measures will help keep these organophospates out of the water," said Josh Osborne-Klein, an attorney for Earthjustice, the public interest law firm that brought the case. "That is not only good for salmon and good for wildlife, but good for people, because these pesticides have been detected in drinking water."
The chemicals, found by the U.S. Geological survey to contaminate rivers throughout the West, interfere with salmon's sense of smell, making it harder to avoid predators, locate food and even find their native spawning streams and reproduce. At higher concentrations, they kill fish outright.
"It makes no sense to allow uses of pesticides that poison salmon while we are trying so hard to save them," said Glen Spain of Pacific Coast Federation of Fishermen's Associations, a plaintiff in the case.
Banned from many household uses, tens of millions of pounds of the chemicals are still used throughout the range of Pacific salmon on fruits, vegetables, forage crops, cotton, fence posts and livestock to control mosquitoes, flies, termites, boll weevils and other pests, according to NOAA Fisheries.
The U.S. Environmental Protection Agency has a year to implement the findings.
Buffer zones imposed by a federal judge in the case are expanded to 1,000 feet from streams for aerial spraying, 500 feet for ground spraying, plus a 20-foot strip of grass or brush. The chemicals cannot be sprayed when the wind is blowing or when a major storm might wash them into the water.
The old buffers were 300 feet for aerial spraying and 60 feet for ground spraying, with no vegetation strip required.
"This is a step forward, I think an important step forward, but there is lots more to do," said Jim Lecky, director of protected species for NOAA Fisheries. "It's one of a gazillion things we need to work on. I think it's important to clean up waterways to optimize their reproductive capacity."
Plaintiffs in the case hope the expanded buffers will convince farmers and growers to drop use of the chemicals entirely and turn to alternatives or even organic farming, Osborne-Klein said.
That would be a hardship for growers, particularly apple and cherry growers, said Heather Hansen of Washington Friends of Farms and Forests. Without them, apple growers that get coddling moths and cherry growers that get cherry fruit flies could be quarantined and unable to sell their fruit.
She added that organophosphate use has been declining in recent years, with water samples by the state of Washington showing cleaner water.
"The way they are using these products today, nobody has shown evidence of harm to fish," she said. "This is really about paperwork - government agencies not doing paperwork and not communicating well with each other."
The chemicals are the first of 37 that NOAA Fisheries and EPA must evaluate by 2012 under terms of a settlement reached in a lawsuit brought by Northwest Coalition for Alternatives to Pesticides, Washington Toxics Coalition and the Pacific Coast Federation of Fishermen's Associations, which represents California commercial salmon fishermen.
A total of 28 species of Pacific salmon are classified as threatened or endangered from overfishing, dams, logging, grazing, urban development, pollution, irrigation, misguided hatchery practices and other threats.