The controversial approval last month by the state Department of Pesticide Regulation (DPR) of a highly toxic chemical for use on California strawberry fields and fruit orchards has sparked a lawsuit by farmworkers and environmentalist seeking to overturn its regulation.

Plaintiffs argue that the DPR fast-tracked the review of methyl iodide, a state-listed carcinogen whose fate as a farm input was to be decided after the state's budget crisis was brought under control. Furthermore, they allege the state then invoked an emergency regulation to illegally circumvent mandated public hearings.

The issue lies with those living and working next to areas where fumigants are used said Susan Kegley, a consulting scientist for Pesticide Action Network North America (PANNA) – one of five organizations that filed the lawsuit last week in Alameda County Superior Court.

According to a PANNA press release:

“Methyl iodide causes late term miscarriages, contaminates groundwater and is so reliably carcinogenic that it’s used to create cancer cells in laboratories. It is included in California’s Proposition 65 list of 'chemicals known to cause cancer.' The pesticide poses the most direct risks to farm workers and neighboring communities because of the volume that would be applied to fields and its tendency to drift off site through the air.”

Approved by the EPA in 2007, methyl iodide was illegal in California until DPR officials completed their own risk assessment of the pesticide weeks ago.  It was meant to replace methyl bromide, an ozone-depleting pesticide that is being phased out under international treaty.

Although the DPR's own scientific panel concluded that there is overwhelming evidence against any possible safe agricultural use of the fumigant, regulators say special restrictions on its use will mitigate any poisoning side effects to farm hands, their families and those who eat the food produced from methyl iodide-treated soils.

"Methyl iodide is the most evaluated pesticide (in) the Department of Pesticide Regulation's history," claims department spokeswoman Lea Brooks. "DPR's evaluation determined methyl iodide can be used safely under its toughest-in-the-nation health-protective measures, including stricter buffer zones, more groundwater protections, reduced application rates and stronger protections for workers."

A scientific review committee studied the chemical last February and expressed disbelief that methyl iodide was even being considered for use on farms.

"Based on the data available, we know that methyl iodide is a highly toxic chemical and we expect that any anticipated scenario for the agricultural or structural fumigation use of this agent would result in exposures to a large number of the public and thus would have a significant adverse impact on the public health," wrote the panel of scientists in their report.

According to the Contra Costa Times:

“The new state regulations require larger buffer zones that federal regulators required. Pesticide applicators in California will have to use nearly impermeable tarps to cover fields after methyl iodide is applied, among other restrictions.”

Even so, the potential of methyl iodide to contaminate groundwater is high say scientists.

Though research has inferred a causal link, Kegley says there is no reliable data on methyl iodide and cancer in humans. Speaking to the L.A. Times, Kegley said “This would be a first, and we Californians would be the guinea pigs in that experiment.”

Only those with a permit from a county agricultural commissioner are authorized to use methyl iodide.