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Dpr Announces Decision To Register Methyl Iodide

Dpr New Release


SACRAMENTO – Department of Pesticide Regulation (DPR) Director Mary-Ann Warmerdam today announced that the registration of methyl iodide will occur later this month as soon as emergency regulations take effect to designate the fumigant pesticide as a restricted material.

SACRAMENTO – Department of Pesticide Regulation (DPR) Director Mary-Ann Warmerdam today announced that the registration of methyl iodide will occur later this month as soon as emergency regulations take effect to designate the fumigant pesticide as a restricted material. The decision follows the U.S. Environmental Protection Agency’s (U.S. EPA) approval of California-specific labels for four methyl iodide products with stringent health-protective measures required by DPR.

Restricted materials require a use permit from the agricultural commissioner in the county where the application is planned. State pesticide laws are enforced by county agricultural commissioners, who can impose tougher restrictions tailored to local conditions.

"Methyl iodide is the most evaluated pesticide in the department’s history," Warmerdam said. "Methyl iodide can be used safely under our tough restrictions by only highly trained applicators at times, places and specific conditions approved by the county agricultural commissioners."

California’s use restrictions on methyl iodide are more stringent than those required by U.S. EPA, Florida and other states where it is applied. U.S. EPA registered methyl iodide in 2007 as a replacement for methyl bromide, which causes damage to ozone in the upper atmosphere. Methyl iodide does not harm the ozone layer.

Methyl iodide will be legal for use in California after the emergency regulations take effect in late December. The emergency regulations are necessary so methyl iodide can only be used with a permit from the county agricultural commissioner.

DPR received more than 50,000 public comments after Warmerdam proposed registration of methyl iodide in April. Most of the comments expressed concern about potential health risks from methyl iodide applications.

"We acknowledge there are strong and diverse opinions on methyl iodide registration," Warmerdam said. "Methyl iodide is a chemical designed to kill pests and soil-borne diseases. We based our decision on the risk assessment by our scientists and a risk-management process that determined what measures are required to keep exposures to methyl iodide within safe levels. With these safeguards, methyl iodide can be used without exposing workers and the public to harmful levels."

Since DPR announced its proposal to register methyl iodide in April, the use restrictions have been clarified and strengthened, including stricter buffer zones, a requirement that only DPR-approved highly retentive tarps be used, more ground water protections, reduced application rates and stronger protections for workers.

In addition, as part of its obligation to continuously evaluate all registered pesticides, DPR will conduct sampling of water and soil in areas with high methyl iodide use to monitor the effectiveness of the mitigation measures.