Ozone: it’s the perfect example of a happy medium. Too close and it’ll crisp your lung tissue. But up in the sky it’s a protective shield, protecting all things living from the sun’s stark light. Happy mediums exist down on God’s green earth, too. Do we spray a harmful chemical that allows us to harvest a bumper crop? What if that spray destroys the ozone layer that allows us to grow anything at all?
This is the quandary that farmers faced—until the infamous ozone-destroying agricultural pesticide methyl bromide was banned. The phasing-out took decades, its use drastically curtailed under the 1987 Montreal Protocol in the late 1990s to the present, with increasingly stringent regulations. It is still employed in restricted quantities for fumigating quarantined crops and for “critical and emergency uses,” which include using it to kill imported organisms that might otherwise be introduced into the United States. In developed countries, farmers are allowed to apply up to 14,600 tons of the chemical in 2006, according to United Nations documents.
So what’s a farmer to do? Not go organic, apparently: earlier this year, the U.S. Environmental Protection Agency considered an application by Tokyo-based Arysta LifeSciences to begin listing methyl iodide, a fumigant that could be used to sterilize the fields and storage rooms where strawberries, tomatoes, and melons are grown and stored. Listing is one of the first steps in getting a pesticide approved for use. Appalled environmentalists, who had spent years campaigning against methyl bromide, immediately mobilized to fight what some have dubbed “son of methyl bromide.”
Some say the nut doesn’t fall far from the tree. “It’s not an ozone-depleter, but that’s about the only nice thing you can say about it,” says Susan Kegley, senior staff scientist with Pesticide Action Network North America (PANNA). “It’s more acutely toxic and a stronger carcinogen, sometimes [causing cancer] with only a single application&.” Because of this, it’s not registered for use anywhere in the world—except Japan. “The European Union uses the precautionary principle, so it probably won’t be registered there,” Kegley says. “It has been approved in Japan for fumigating imported timber, the first allowed use in the world.”
The EPA and the California Department of Pesticide Regulation differ about the health impacts of methyl iodide. Citing concerns for pregnant women and fetuses, DPR disagreed with the EPA’s assessment that health effects on workers and the nearby community could be mitigated through precautionary procedures and in the case of workers, protective clothing. It also disputed the “safe” level of the pesticide, which the EPA estimates to be about five times higher than the DPR safe level. The DPR also says that it is “very concerned” about possible neurological disruption and the consequent effects on fetuses.
Most growers now lament the good old days, when one application of methyl bromide could boost productivity for several years. When used as a soil fumigant, methyl bromide left no residue, and it virtually sterilized the soil of all life, including insects, nematodes, molds, and fungi. It gave strawberries and other crops several years of pest-free growing time. Lettuce farmers often leased the land after strawberry crops had been grown in the fumigated soil because the sterilization killed off lettuce pests too. Vineyard growers often used methyl bromide as a fumigant before plants went in, so the chemical has been widely used in Northern California. Even anti-pesticide activists concede that no presently available chemical or combination of chemicals is as effective or long lasting as methyl bromide. “There’s nothing else like it,” say both growers and activists.
But interestingly, grower organizations have stopped short of adopting an official position advocating methyl iodide, which is the one chemical that seems to be as effective as methyl bromide in killing virtually everything in the soil. As Mary DeGroat, public relations director for the California Strawberry Commission, recently told the L.A. Times, “We are hoping to find something as efficient and cost-effective as methyl bromide, but we’re not proponents” of any particular chemical. “If an alternative comes up that works and is safe, then that’s great news. Whatever the [EPA and state] deem legal and appropriate, we work within those realms in compliance. If they approve methyl iodide, obviously there would be some training involved. That would be critical.”
Environmentalists point out that there is nothing that works like these chemicals because those who use chemical pest controls often refuse to consider other techniques. As methyl bromide was phased out, experimentation has flourished in alternative methods such as solar heat sterilization, intercropping, crop rotation, and other less toxic controls. “You seem to need the threat of something going away to get innovation like that,” says Kegley.
The EPA says that it is now reviewing methyl iodide as part of a larger fumigant assessment study of half a dozen pesticides. The results of the study are expected by the end of this year, when the EPA has said that it will reconsider the registration of the chemical. It denied listing this spring.
Kegley views the denial to list methyl iodide as a victory, citing citizen action and PANNA’s vigorous protests as important in the EPA’s decision. “The EPA was really pushing this through, and we slowed it down,” she says. A PANNA spokesperson says that a public awareness campaign from a coalition of environmental, health, and social justice organizations helped to generate more than 12,500 comments. Stay tuned for the next installment in the continuing saga, some time early next year, shortly after the EPA completes its long-awaited fumigant review.