Methyl iodide doesn’t make health sense, but it doesn’t make financial sense either.

The Board of Supervisors recently took a stand against the fumigant methyl iodide, in a vote that followed the kind of political calculating in service since Cicero first described it in 50 B.C. A supervisor being challenged by an upstart decided to ally himself with workers who might vote against him rather than with produce companies that always funded him. His colleague, previously on the fence, jumps over with him and the vote swings 4-1, no complicated math. 


Methyl iodide, also known as Mel, is a chemical under attack because of its lethality. Fumigation “cleans” fields by attempting to kill all exigent life forms – fungal, bacterial, viral and animal. Unlike some fumigants, Mel also is a potent carcinogen. It is supposed to replace methyl bromide, which hasn’t been manufactured in years due to its capacity to deplete the ozone layer. 


Mel’s approval followed a tortured political history in which the Bush Administration lobbied the U.S. Environmental Protection Agency to fast track its approval despite the dire warnings of chemists. The California Department of Pesticide Regulation, whose director ignored her own staff and an independent scientific committee that concluded that Mel was unsafe at any exposure level, approved it. 


What no government agency performed is a basic cost/benefit analysis. How dangerous is Mel, versus its effectiveness, in light of cost? Since the main crop use of Mel is on strawberries, we can start the primer here in Monterey County. All numbers are approximate averages. 


A typical field acre might produce 5,000 boxes of berries that sell for $7 per box. The pre-harvest cost is $12,000 and variable costs (picking, hauling, post-harvest spraying and weeding, supervision) are $4 per box. Pre-harvest costs are for conventional (non-organic) fields using the older, cheaper fumigant chloropicrin.


Now, this is the conventional scenario not accepted by organic farmers who don’t buy into the nuclear option of soil fumigation and believe pathogens come in the good and bad varieties. With lower yields they sell to consumers who pay to ingest more bugs but fewer toxins. 


Back to the math. If the farmer sees $3 net return, his first 4,000 boxes pay pre-harvest costs. If “better” fumigation costs an additional $1,500 per acre, then the farmer would need 500 more boxes per acre to pay the added cost. The “best” conventional farmers say they get 8,000 boxes using more plants, more fertilizer, fewer weeds and maybe some number fudging. Such farmers might try Mel in spite of published data showing that the fumigant chloropicrin provided yields about 95 percent equal to methyl bromide. Five percent of 8,000 is 400 boxes – still short of profitable. 


Astonishingly, nobody, including the feds or the state, bothered to test chloropicrin against Mel – something required under a state law called CEQA which mandates considering alternatives. Farm worker advocates filed for a court injunction to stop its use. “Did you ever consider not approving methyl iodide?” asked Judge Frank Roesch in Alameda Superior Court. 


Why shouldn’t a farmer beat the averages? The reason is public policy, through regulation, counts the cost of “bad outcomes” – oil covered beaches, flooded cities, diabetic children and, more pertinent here, cancer treatment. All of this would have required comparative baseline data for all three fumigants in terms of toxicity and effectiveness. This was never done.


In the end, the supes got it right. Gov. Brown should start with a science-based, cost/benefit analysis. Judge Roesch might mandate it, but Monterey County supervisors should require it. 


HERB AARONS, former president of California Coastal Rural Development Co., now consults to California FarmLink, an advocacy group for small, organic farmers.