Can methyl iodide be used as a pesticide?

A strawberry grows at Glen Hasagawa's farm in Oxnard, Calif.


Bob Moon: Regulators here in California just approved the use of a controversial pesticide. And if you like strawberries, or anything with strawberries, here's why you might care: California grows 90 percent of the country's strawberries, and the state's approval of this pest-killer is aimed at supporting its billion-dollar-a-year strawberry industry. No one disagrees that methyl iodide is toxic. The debate is whether or not it can be used safely.

From the Marketplace Sustainability Desk, Adriene Hill reports.

Adriene Hill: It's a misty, gray day in Oxnard, Calif. I'm standing on the edge of 35 acres of strawberry plants.

Farmer Glen Hasagawa looks out at his field -- green splashed with white flowers and a few red berries -- and seems pleased.

Glen Hasagawa: They are little power plants. They're definitely work horses.

But Hasagawa's work horses are susceptible to disease, fungus, mold and pests. So Hasagawa uses pesticides and fertilizers to keep them producing.

Hasagawa: You know, if you have some pest outbreak in your house, the first thing you do is you pull out some ant spray or something like that, and that's kind of what we have to do too, but on a much larger scale.

Right now, one of the tools Hasagawa uses is a fumigant called methyl bromide. But methyl bromide damages the ozone layer, and international officials got together and agreed to stop using it. So farmers are scrambling to find substitutes -- and lots of them are turning to methyl iodide.

John Froines: I think this is an extremely dangerous chemical.

John Froines is a professor at UCLA. He headed a group of scientists the state asked to evaluate the chemical. Froines and his colleagues say it's too dangerous to be used safely (PDF); it poses risk to people applying it and those who live nearby.

Froines: There were a number of case studies in which humans had been exposed to methyl iodide, and the effects of the methyl iodide were absolutely devastating.

Froines says case studies showed neurological damage. In laboratory animals, there's also evidence of "fetal death" and cancer. So Froines and his colleagues advised the state against approving methyl iodide. But California regulators went ahead and OK'd it.

Mary-Ann Warmerdam: This particular material, methyl iodide, has been the most comprehensively reviewed material in our history.

Mary-Ann Warmerdam heads the California Department of Pesticide Regulation.

Warmerdam: We are confident that with the health protective measures that we have put in place, that it can be used safely in California.

The state allows 100 pounds of the chemical per acre, a number that makes California's laws among the strictest. The feds are OK with nearly double that.

Warmerdam: What we look for is if certain materials, chemistries, are required for production. Can we have a reasonable degree of certainty that they can be used safely?

And really, that's what we ask regulators to do everyday -- to judge public health risk in the context of social, economic and environmental pressures.

Back out at the strawberry farm, Glen Hasagawa trusts the state to get it right.

Hasagawa: Since it is approved for use, I would be confident that we could use it safely.

Hasagawa isn't in a rush to use the new chemical. He wants to see how other farmers are faring with it first, but he says he's open to it. He grows some raspberries organically, but says organic strawberries just aren't doable, at least not for what the market's willing to pay.

Hasagawa: If we get a soil-born disease, we could lose our whole field, so we couldn't charge enough to make it feasible for us. It wouldn't pencil at all.

And strawberries that cost an extra 50 percent might not "pencil" for most of the rest of us; we like our food cheap. So, Hasagawa, like most other strawberry farmers, uses the tools that are available. And the state and federal government say methyl iodide can be one of those tools, even if many scientists and pesticide activists disagree.

I'm Adriene Hill for Marketplace.

MORE INFORMATION: There are two states that do not allow methyl iodide: Washington and New York. And an EPA spokesman says the agency has no plans to reevaluate its approval of methyl iodide in the immediate future. The follow are a collection of resources with information and background on the methyl iodide debate:

The California Department of Pesticide Regulation distributed a press release on the decision to register methyl iodide.

Background on California's registration process

Information on methyl iodide from the EPA. The letter signed more than 50 scientists recommending the EPA (PDF) not allow farmers to use methyl iodide.

Information on methyl iodide from the Pesticide Action Network

Press release about California's decision to allow methyl iodide from the chemical maker, Arysta Life Science.

About the author

Adriene Hill is a senior multimedia reporter for the Marketplace sustainability desk, with a focus on consumer issues and the individual relationship to sustainability and the environment.
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Market Place- I am a teacher in the Pajaro Valley where most of the elementary schools are located next to, or close by to these fields. My students are smart, beautiful and precious children, our future generation. Just visit one of these classrooms, read the letter from the scientists asked to present their educated opinion quoted below, and then think about if there are two sides to this issue. Money or our children????
As members of the scientific community, we urge you to do whatever is possible to prevent this chemical
from ever becoming a registered pesticide. At the very least, we ask that you delay the decision and
assemble a blue-ribbon panel of independent (conflict-free) scientists such as a committee of the National
Research Council to provide peer review and scientific scrutiny of U.S. EPA’s safety assessment of this
chemical. We would be happy to suggest panel members.
Thank you for your consideration.
Sincerely yours, The Scientists

To Mr. Medrano -
You are right, I am not working in the fields every day, but I both work and live very close to strawberry fields, and I am out in fields on a regular basis. The growers I know are concerned about the health and welfare of their workers, families and neighbors. The stringent regulations governing methyl iodide use will likely eliminate any fields near homes and schools.

Thanks for getting all sides' comments into your interview piece, Adriene. Use of agricultural plant health materials and processes is a very complex matter. Everyone comes into contact with toxic substances virtually every day--household bleach, drain cleaner, gasoline, cigarette smoke, and a variety of over-the-counter (but untested) and prescription drugs--and we accept without thought risks that are very real and far more hazardous to our persons and children--driving the freeways, crossing streets, even catching airplane flights. When state and federal regulatory agencies that have conducted years of study and required research is involved, somehow all of these familiar issues become sensitized and falsehoods begin to be thrown around as "facts". Methyl iodide protects the ozone layer, unlike its predecessor methyl bromide. It requires far less product in application, and the safety measures are much more strict. It is gone from the field before any strawberries are planted there, and despite claims that organic production methods produce equal or superior results with equal reliability, those claims are false. The choice without a soil fumigant (which is used for 90+ percent of all strawberry plantings--and extensively at nurseries for most other food, nut, and fiber crops) is that commercial farming will be much less productive, less economical, and we will end up eating food grown overseas without regulations equivalent to those found here. If you like being dependent on foreign oil, you'll love foreign food!

To Carolyn:

Regardless whether MeI is applied to the soil or to the food itself, it is still a very dangerous chemical that will be used in massive quantities in our environment. I doubt that you work out in the fields applying and removing tarps, or breathing in dirt every day. My back yard is literally a field of strawberries, not by choice. The MeI issue is not about consumer safety, it's about resident (including children) and worker safety. Mostly all schools in the PVUSD are close to a conventional field.

Tell me, if MeI is so safe, why did it go through such an intensive review by the Cal DPR?

Einstein is reputed to have said "The significant problems we have cannot be solved at the same level of thinking with which we created them." That quote applies to agriculture just as much as it applies to great power politics and war. Show of hands: how many people think “organic” agriculture is the same just chemical agriculture without the chemicals? Do the phrase “integrated pest management” mean anything to an agricultural engineer who has been trained in the solve-everything-with-better-bombs[pesticides] age?

I'm curious if perhaps a 50% increase in cost is the cost of discontinuing use of pesticides and fertilizers but keeping all other production methods the same. Effective organic growing often involves rotating crops, not only for soil fertility but also for pest control. Would a 50% price increase be the cost of using enough "organic fumigant" to plant strawberries in the same plot year after year and to accept losses due to disease in that same time? Or, does it consider: planting crops that are not hosts for Verticillium wilt 3 out of every 4 years? planting hedgerows to support pest predators? use of mustard cover crops to fight wilt and weeds?

I suspect that those who will succeed as farmers in a market environment that increasingly demands organic food products are those farmers who are able to apply an ecological model of thinking to their crop production. Good luck, Glen.

It is disappointing that Marketplace so often uncritically repeats the myth that chemically-reliant farming is necessary. Strawberries are a perfect example: growers large and small are successfully producing strawberries organically. Recent research has shown California organic strawberries to be healthier with longer shelf life, while the ecological approach builds soil for future generations. Fumigants like methyl bromide and methyl iodide destroy healthy soil along with pests -- they are inherently unsustainable, antiquated technology. But most immediately tragic is that you suggest that "most of the rest of us" will "pencil" out the health of farmworkers and people who live near fumigated fields for a little cheaper luxury fruit.

You got one thing right: scientists agree methyl iodide is extremely toxic. What you missed is that Japan's Arysta, the largest privately held pesticide company in the world and sole manufacture of this new fumigant, won this round by employing expensive lobbyists and PR flacks who spun the story as "farmers' survival requires manageable risks". No disinterested scientists agree. Methyl iodide is all about profit over public health; that's what motivated CA officials, and that's the story you bought.

Farmer Glen Hasagawa seemed to be saying that the only way to grow good strawberries is with toxic chemicals. This would be a surprise to companies like Driscolls Berries, one of the – maybe THE – largest strawberry growers in the state. Driscolls has a strong commitment to growing berries organically, using crop rotation and careful growing practices rather than chemicals. Using poisonous chemicals instead of conscientious and proven organic farming practices is one of the reasons we all carry a heavy load of toxic chemicals in our bodies.

Some of the comments are also misleading. 2010 was a great year for Strawberries and there was a glut on the market which drove prices down. Commenters need to compare prices for a more normal year like 2007.

Second, please remember that methyl bromide was a relatively safe and very effective fungicide that never came in contact with the commercial product. The need to use methyl iodide is the unintended consequence of an outright ban on methyl bromide. If methyl bromide were applied with the same strict containment techniques required of its successor, its impacts on ozone depletion would be minimal.

This story does not provide the whole story about strawberries and agrochemical farming and contains inaccurate information. I too can buy organic strawberries for 25 to 50 cents more than pesticide grown ones. Not 50 percent higher. Of course strawberries can be grown organically! It’s too bad the reporter didn’t take the time to speak with a farmer growing USDA Certified organic strawberries.

It’s also unfortunate that the reporter didn’t consider mentioning the ‘hidden costs’ of agrochemical farming - health damage to people, pets and wild animal. Chemical contamination of our environment and its link to global pandemics. Soil and water resources being polluted and depleted. Destruction of global agriculture. Global climate change - agrochemical farming creates 1/3 of global greenhouse gas emissions. Destruction of fragile ecosystems and global biodiversity. Decline of pollinators. Continued contribution to the ‘circle of poison’’. Decimation of global wild bird populations. In the US a minimum of 67 million birds die each year from agrochemical farming. Read my entire column, “The Holistic Parrot” that discusses this topic in-depth in the November, 2010 issue of “Parrots” magazine ( www.parrotmag.com).

I trust USDA Certified Organic organic farmers to get it right - not the state of California.

It’s disappointing to know that American Public Media allowed it to air. it makes me wonder how many other stories - that I’m not well versed in - also contain false or prejudiced information.

It's disappointing to see so much of the information provided to the reporter omitted for this story. Probably the most misleading is the implication that methyl bromide or methyl iodide is applied directly to strawberries, when it would be used to prepare the soil weeks before the plants are put in the ground.

While the previous commenter found organic strawberries in a market for nearly the same cost as conventionally grown strawberries, the price in the market does not reflect the price the farmer gets or needs to get to remain in business.


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