Opponents of methyl iodide use in California have stepped up this week, with a coalition of advocacy groups taking to the courts to block the state’s recent approval of the pesticide.

California’s Department of Pesticide Regulation (DPR) finally got round to approving the use of the fumigant in December last year, despite some pretty serious objections. Although the Environmental Protection Agency approved methyl iodide in 2007, the DPR’s own reports have noted that it could present “significant” health risks (see: “Scientists fume over California’s pesticide plans”, 4 May 2010).

In filing their lawsuit against the approval, groups including Californians for Pesticide Reform note that on the same day the DPR finally registered methyl iodide it proposed an emergency regulation to designate the pesticide a restricted material. This is in part because, as the DPR says, “the unrestricted use of methyl iodide could pose unacceptable risks to human health”.

“DPR’s approval of methyl iodide is irresponsible and illegal. There is no question that the chemical is highly toxic,” says the lawsuit, which claims the approval violates the California Environmental Quality Act, the California Birth Defects Prevention Act, and the Pesticide Contamination Prevention Act.

Its advocates insist the chemical – which is coming in as ozone depleting methyl bromide is phased out – can be used safely. The DPR says California’s rules on its use are to be tougher than any other state’s.

“Methyl iodide is the most evaluated pesticide in the department’s history,” said its director Mary-Ann Warmerdam last month. “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.”

So, a nice little mess for California’s new governor Jerry Brown to sort out in his first week in office. Good luck in your new job Mr Brown.

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