Skip Navigation

California Weighs Opinions On Safety Of Methyl Iodide

Capital Press


By Wes Sander - Capital Press SACRAMENTO -- While California farmworkers say they fear approval of a soil fumigant described as highly toxic, agriculture advocates are expressing frustration with the Department of Pesticide Regulation's long approval process for methyl iodide.

By Wes Sander - Capital Press
SACRAMENTO -- While California farmworkers say they fear approval of a soil fumigant described as highly toxic, agriculture advocates are expressing frustration with the Department of Pesticide Regulation's long approval process for methyl iodide.

Methyl iodide is being considered by state officials as a fumigant to replace methyl bromide, which has been phased out since the early 1990s under international agreement due to its ozone-depleting properties.

California is one of the last states to register methyl iodide for commercial use. Some scientists have described the chemical as highly toxic and dangerous. Others have said that with proper handling, its risk to human health is low.

"California has always been the bellwether for imposing stricter regulations," said Steve Scholl-Buckwald of Pesticide Action Network, which opposes registration of methyl iodide. "And of course it would be by far the biggest market."

At a peer-review workshop conducted Sept. 24-25 in Sacramento, a number of farmworkers and worker advocates used a public-comment session to tell stories of bad experiences resulting from exposures to farm chemicals.

Meanwhile, Michael Allan, an executive with Tokyo-based Arysta LifeScience, said California's process is needlessly keeping a safe and useful tool out of the hands of farmers. Arysta licenses the compound from the University of California, which holds a patent for its use as a pesticide.

"It can be used safely," Allan said of methyl iodide. "It can be applied accurately. And it reduces the amount of (chemicals) that are used."

The U.S. Environmental Protection Agency registered methyl iodide in 2007. Every state except Washington, New York and California has since registered the chemical for sale and use.

"We are three years behind EPA," Allan said. "That's uncalled for. We have this entire process that is essentially a barrier for us."

The bulk of fumigant usage occurs in California and Florida, Allan said. Most states defer to EPA's review to satisfy their own registration requirements.

DPR cites California's abundance of specialty crops -- which require large numbers of workers in close contact with plants and soil -- and its tight mingling of urban and agricultural areas as reasons for its stringent approval process.

The independent peer review, being conducted by a panel of UC scientists, is part of an elective risk-assessment process that is not required by state rules. DPR has said it may reconsider registration based on conclusion drawn by the peer review.

Husein Ajwa, an extension researcher with the University of California-Davis who has researched methyl iodide for the past decade, argues that the chemical is safe when used properly, and more efficient than methyl bromide.

Without it, producers would require several different pesticides to disinfest soil, Ajwa said.

"Without iodomethane we will have to keep using other fumi


Visit Capital Press here