Memos show staff questioned rationale for pesticide approval

Environmentalists fighting to roll back the approval of a controversial pesticide released documents Thursday that they said show regulators put politics before science when they approved methyl iodide for use in California agriculture last December.

“They take all the technical numbers and do this mix and match,” said Greg Loarie, an attorney for Earthjustice, which has sued the state Department of Pesticide Regulation on behalf of farm workers and environmental groups over its decision.

DPR spokeswoman Lea Brooks declined to comment, citing the pending litigation.

“Earthjustice is one of the litigants. It is inappropriate to try this case in the media,” Brooks wrote in an email.

Methyl iodide, now marketed as Midas, is designed to kill weeds and soil pests before strawberry, tomato and host of other plants are put in the ground.

Its manufacturer, Arysta Lifesciences, has touted the chemical as a so-called drop-in replacement for methyl bromide, which many California growers had widely depended on, but which is now being phased out under the Montreal Protocol because it depletes the earth’s ozone layer.

DPR scientists, however, concluded in early 2010 that it was only safe for use at low levels far away from homes and schools.

But in the last days of the Schwarzenegger administration, DPR managers appeared to disregard those conclusions and approved methyl iodide for use at concentrations 120 times higher than those its staff scientists had recommended.

An April 28, 2010 memo from primary state toxicologist Jay Schreider to supervisor Gary Patterson, which was released by Earthjustice Thursday questions the managers’ decision-making process.

“I am.. puzzled by some of the numbers cited in the draft regulation on methyl iodide …,” Schreider wrote.

“They appear to have been extracted from different MeI [methyl iodide] risk assessment methodologies that are not interchangeable. Each approach is made up of a series of interrelated values and assumptions: one value or assumption is predicated on the preceding one. It is not scientifically credible to select a value or assumption from one and combine it with a value or assumption from another.”

Schreider appears to have written his memo in response to a draft notice of decision dated the day before, in which DPR managers outlined a rationale for methyl iodide approval.

After looking over that draft, Dr. Susan Kegley, a consulting scientist for the Pesticide Action Network, which is also a plaintiff in the Earthjustice lawsuit, said DPR managers seemed to cherry pick numbers from two different mathematical models used to estimate methyl iodide’s toxicity to humans.

“You can’t take just the bits and pieces you want to get the number you want at the end,” Kegley said.

Earthjustice obtained the memo and draft decision along with some 800 pages of methyl iodide material last week when Alameda County Superior Court Judge Frank Roesch ordered the DPR to release them in connection with the Earthjustice litigation.

DPR has staunchly defended its decision to register methyl iodide
Brooks pointed to a statement former DPR Director Mary Ann Warmerdam gave at a legislative hearing last February.

“The restrictions and conditions California has imposed on the use of methyl iodide products are the most stringent that exist in the United States, including those required by U. S. EPA,” Warmerdam said.

The document release comes as Pesticide Action Network has launched a renewed effort to pressure the Brown administration to reverse the Schwarzenegger decision.

“We think today’s release is enough information to give the governor and his administration pause to consider taking methyl iodide off the shelf,” said Paul Towers, a spokesman for the group.

A spokesman for Gov. Brown declined to comment.

X Close

Subscribe to Our Mailing List