Pesticide Guthion will be phased out after 2012

Cherry growers are among the last farmers using a potent pesticide being phased out by the government. Guthion(ai: azinphos methyl) is a nerve toxin and very effective at killing insects. But the EPA says it poses an unacceptable risk for farm workers and also has killed fish when sprayed over water. The agency has decided nobody can use Guthion after the summer of 2012. A small group of growers has been trying to find a replacement.

For 50 years, growers have relied on Guthion to keep worms and the grubs out of your fruit. It was derived from World War I nerve toxins. Some growers just call it the hammer. And when they spray it every little insect in the orchard is a nail.

Jim Laubach is an orchard scout helping growers test new pesticides. Even though he has seen the number of cherry fruit flies explode in test orchards this summer, hes pretty confident the new pesticides can work.

"You have to use two to do the job that one used to do," says Laubach. "It may be 5 or 6 times the cost of Guthion to do the same thing."

But the lead researcher from Michigan State University is less optimistic about the prospects for replacing Guthion. Mark Whalon has spent 25 years helping growers control pests in their cherry orchards. Theyve learned a lot more about the life cycles of insects so growers can use less chemicals and time their spraying to be more effective. But this sophisticated system is disrupted by the loss of Guthion because that was the foundation, the quick-acting heavy hitter that would reliably knock down the most troublesome pests. Whalon says as a result the failure rate in the test orchards is too high.

"We had a system that failed once in four or five hundred times," says Whalon. "Now we have a system thats failing 25 or 30% of the time. 40% in some years."
Failure, meaning bug is found in a cherry, can be disasterous for growers. There is zero tolerance for insects in todays cherry industry. And if any are detected when the grower delivers his fruit to the processor, the entire load is dumped. And the stakes are higher with computer tracing systems. If a load of cherries is processed and gets into a product like a muffin or ice cream, the cost of entire food recall could come back on the farmer.

But while researchers look for alternatives to Guthion, groups on the other side of the country are working to hasten the ban on the pesticide. In western states like Oregon and California, farm workers and their families are being tested, and evidence does point to neurological problems due to exposure to pesticides such as Guthion. Several groups representing those workers say fruit growers have had more than enough time to find alternatives. In 2006, EPA gave them six more years. Farm worker and environmental groups are asking a federal court to ban the pesticide immediately.