After years of debate and strong opposition from scientists and environmental groups, the state’s Department of Pesticide Regulation (DPR) gave final approval on Dec. 1 to using the pesticide methyl iodide on California’s strawberry crops.
Methyl iodide, also known as iodomethane, is listed by the state as a carcinogen under Proposition 65. It’s a fumigant injected or
drip-irrigated to eradicate weeds, insects, and plant diseases, and it replaces methyl bromide, a pesticide banned by the 1989 Montreal Protocol for its ozone-depleting properties.
The chemical’s registration comes despite studies linking its use to cancer and other serious disorders, and an in-house DPR report released in 2009 stating methyl iodide fumigation “results in significant health risks for workers and the general population.”
However, according to DPR director Mary Ann Warmerdam, strict state controls on the pesticide’s application will curb the risks to public health.
“We acknowledge there are strong and diverse opinions on methyl iodide registration,” Warmerdam said in a statement. “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.”
Following the agency’s decision, a coalition of farmworker and environmental advocacy groups, including scientists, urged Governor-elect Jerry Brown to overturn it.
“It’s a bad move for California,” said Susan Kegley, chemist and director of the Pesticide Research Institute in Berkeley. “This just puts a big black blotch on the environmental legacy of [Gov. Arnold] Schwarzenegger’s administration.”
“We think this is going to be a disaster for people living around strawberry fields, like Santa Maria, and all over the Central Coast, where there will likely be some use of this chemical,” she added.
In a message posted online, United Farm Workers’ president Arturo Rodriquez voiced his displeasure with the registration, saying field workers will be the first to feel the effects.
“So many of California’s good laws and regulations protecting farm workers are ignored by too many growers—and state enforcement has been a disgrace under both Republican and Democratic governors,” Rodriguez wrote. “It looks like farmworkers will continue to be society’s canaries.”
The U.S. Environmental Protection Agency approved the pesticide in October 2007 as a potential replacement for methyl bromide; however, California was one of three states—along with Washington and New York—that refused to permit its use. Since proposing methyl iodide’s registration in April, DPR received more than 50,000 public comments, most expressing concern about potential health effects to those living near strawberry fields.
According to scientists, methyl iodide is four times more toxic than its predecessor, and in addition to causing cancer and thyroid problems, the pesticide could lead to miscarriages in pregnant women, as well as birth defects and brain damage in high doses.
Pesticide Research Institute’s Kegley said there’s no “safe” way to apply the chemical.
“With all the restrictions in the world, you can’t keep people from making mistakes,” she said. “We’re humans. Train all you will, but accidents are going to happen.”
Among DPR’s regulations for use, allowable exposure limits for methyl iodide will be set at 96 parts per billion, about half of the limit allowed by the U.S. EPA. In addition to reduced application rates, larger buffer zones, and a ban on nighttime fumigation, methyl iodide use will be prohibited within a half-mile of hospitals, nursing homes, and in-session schools.
Enforcement of the agency’s protective measures will rest on the county’s agricultural commissioners, who’ll have the authority to deny permits and subject unlawful users to fines or criminal prosecution.
Susan Bryant, deputy for pesticide use enforcement with the Santa Barbara County Ag Commissioner’s Office, said current registered fumigators already have the necessary licensing enabling them to use methyl iodide on the county’s nearly 8,000 acres of strawberries. How much the growers will use, or how soon they’ll be able to start fumigating, she said, is anyone’s guess.
Bryant had no comment on the controversy surrounding methyl iodide’s registration, other than to say there was “evidently confusion” about the state’s process for evaluating it.
“There’s a lot of issues about fumigants in general. They are dangerous, but they’re regulated really well,” Bryant said. “All I can say is once it’s registered and they follow any conditions we have—which I don’t know what they’ll be yet—the growers have a right to use it.”
According to DPR, the pesticide will be applied primarily to strawberries throughout the state, but may expand to other high-value crops such as tomatoes and flowers.
Arysta LifeScience Corp. manufactures the five products containing methyl iodide—scheduled for registration on Dec. 20—under the brand name Midas. Emergency regulations, if approved, will classify the pesticides as a restricted material, requiring a permit for use from the county’s agricultural commissioner to the Office of Administrative Law. Public comment on the emergency regulations will be taken by the office until Dec. 13.
But methyl iodide’s opponents aren’t throwing in the towel just yet. According to Kegley, the environmental group Earthjustice—representing Pesticide Action Network and Californians for Pesticide Reform—will file a lawsuit to block the registration, charging the DPR with violating elements of the California Environmental Quality Act and the federal Birth Defects Prevention Act.
“I think the most important thing looking ahead is thinking about how we can productively work with growers to move away from these chemicals,” she said.
Staff Writer Jeremy Thomas can be contacted at jthomas@santamariasun.com.
This article appears in Dec 9-16, 2010.