Despite protests, the EPA approved the use of this potent poison years ago, but a lawsuit moving through the courts could change that.

When researchers want to intentionally create cancerous cells in laboratories, they often use methyl iodide, a chemical that is also a neurotoxin and causes late-term miscarriages. And it kills soil-dwelling organisms -- which is why farmers (particularly strawberry and tomato growers) fumigate fields with it prior to planting.

Calling it one of the most toxic chemicals used in manufacturing, more than 50 scientists, including five Nobel laureates, wrote a letter (PDF) to the Environmental Protection Agency (EPA) toward the end of the Bush II administration pleading that methyl iodide not be approved for agricultural use. To no avail. They failed in California, too, which sets its own environmental regulations, independent of the EPA. But the state followed the EPA's lead and approved it in 2010, just before Governor Schwarzenegger left office.

Last year, lawyers from Earthjustice and California Rural Legal Assistance, Inc. filed suit challenging the chemical's approval on behalf of several environmental and farmworkers groups, who claimed that California officials approved the fumigant despite warnings from scientists in the state's own Department of Pesticide Regulation. Earlier this month, the case came before the Alameda County Superior Court.