EPA OKs use of toxic pesticide on fields

Robert Bergman, the Gerald E. K. Branch Distinguished Professor at UC Berkeley's chemistry department, led the effort by scientists to persuade the EPA to reject methyl iodide. Among the signatories were five Nobel laureates: Robert H. Grubbs of the California Institute of Technology; Roald Hoffmann of Cornell University; Williams S. Knowles, formerly of Monsanto Co.; John B. Fenn of Virginia Commonwealth University; and Richard R. Ernst of the Swiss Federal Polytechnic Institute.

Many of the chemists -- who use small amounts of methyl iodide in their laboratories to attach molecules and are careful to avoid exposure -- said they are shocked that the EPA is allowing its use as a pesticide because it can drift into neighborhoods and pollute groundwater.

"It is potentially really toxic, and it's certainly very reactive. From what we know about its chemistry, we know this stuff reacts with DNA. It mutates it. So it's prudent to be as careful as you can with it," Bergman said in an interview Friday.

Bergman said he was disappointed, but not surprised, by the EPA's decision because top officials there seemed unswayed in discussions with him and two other scientists earlier this week.

The scientists had asked for an independent review by the National Research Council, but the EPA rejected that because its own scientific advisory panel already had reviewed it.

"If they're right, they shouldn't be afraid of an independent review," Bergman said. "I don't know what the motivation is to get this stuff approved so fast. If there is any possibility that it would be dangerous, do you not approve it, or do you approve it and then decide, after something happens, to change your mind? There is serious potential for accidents."

Bergman said he is particularly concerned about neighborhoods in Ventura County and other areas where homes have been built next to farm fields.

EPA officials called their review, which lasted four years, "one of the most thorough analyses ever completed on a new pesticide."

The manufacturer, Arysta, has spent eight years and more than $11 million collecting toxicological and environmental data to persuade the EPA to register methyl iodide as a pesticide.

Arysta's former chief executive, Elin Miller, is now a top official at the EPA and was appointed administrator of its northwest region last year.