Pesticide residues: From fork to farm | Pesticide Action Network
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Pesticide residues: From fork to farm

Karl Tupper's picture

Apples and celery this week. Cilantro a couple back. Stories about pesticide residues on food are making the rounds again. After my umpteenth media call, a blog seemed in order.

As I told the LA Times, here's my basic response: "It’s the farmers, farmworkers and residents of rural communities who are really most at risk" from pesticides, not consumers. While these folks are exposed to pesticides from food like the rest of us, they also must contend with pesticide fumes drifting out of fields, exposure from working directly with pesticides, and pesticide-coated dust and dirt tracked into their homes from the fields. Tom Philpott, newly migrated to MotherJones, nails this topic.

None of this is to discount the accumulating evidence around low-level (possibly dietary) pesticide exposures being linked to ADHD and other cognitive deficits in kids, rural and urban. A constant, low-level pesticide cocktail in our food cannot be good — especially for pregnant women, young children, the sick or the elderly. 

And our own website and iPhone App are designed to give people better insight into which types of residues are in their food and water. Because people want to know. Using a portion of the same data (we also pull and cross-reference toxicity data), the Environmental Working Group just released their updated wallet card with their Dirty Dozen and Clean Fifteen lists of most and least contaminated produce items. All well and good.

But while from an eater's viewpoint the Clean Fifteen fruits and veggies really are a lot cleaner than the Dirty Dozen, from the perspective of farmers, farmworkers, and rural residents, there's not much difference. 

Back to the farm

So, with these caveats in place, I invite readers to consider the following analysis — tracking the residue issue from fork all the way back to the farm:

I looked up the total amount of pesticides applied in California in 2009 to each of the Dirty Dozen and Clean Fifteen items and also the total number of acres planted for each, and calculated pesticide use intensity for each. (I used California data since its the only data available, and since pineapples, mangoes, and blueberries aren't grown in California I had to omit these). Here's what I found:

  • The cleanest crop from a producer's standpoint is actually spinach, with only 0.4 lbs of pesticide used per acre in California. Spinach is fifth on the Dirty Dozen list. 
  • Conversely, the crops with most intensive pesticide use are sweet potatoes and mushrooms, with 110.3 lbs/acre and 106.1 lbs/acre, respectively. These are Clean Fifteen commodities.
  • Overall, the two lists don't look that different from the standpoint of pesticide use. The average pesticide use intensity for the list are quite similar: 26.2 lbs/acre for the Clean Fifteen and 29.8 lbs/acre for the Diry Dozen.

So what's going on? Fumigation is major piece of the puzzle.

As I wrote last week, fumigants are just plain dangerous. They are very drift-prone and very toxic, and they are applied at very high rates compared to non-fumigant pesticides. But because they are applied to soil before crops are planted, and because they are so volatile and so reactive, they don't stick around on growing plants and they don't end up contaminating the food you buy at the market.

Another factor is how we prepare food: no one eats onion skins, corn husks, the outsides of pineapples, avocado shells, or watermelon rinds, and not surprisingly these items are on the Clean Fifteen list. USDA washes and prepares all the foods as we would before testing. Meanwhile, all the fruits and vegetables on the Dirty Dozen list are things we tend to eat whole — skin and all — so any pesticides not washed off will go right down the hatch.

My point is two-fold. 1) The scandal isn't cilantro, or apples. It's 2 million people doing the third most dangerous job in the country for sub-poverty wages, while facing pesticide exposure. 2) We can't shop our way out of this: pesticides are a public policy issue.

Take action » Join concerned Californians who are fighting to keep the potent neurotoxin and carcinogen methyl iodide out of the state's strawberry fields. And yes, strawberries are consistenly among the Dirty Dozen, but not because of methyl iodide.

Karl Tupper
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Toxed2loss's picture
Toxed2loss /
Hi Karl, I am severely disabled by pesticide poisoning. It's a "toxic injury." I also live on a farm in an agricultural community. While I whole heartedly support Panna, and all the work you do, I have a unique perspective that I'd like to bring up. When I became injured through deliberate misapplication by an Ag pilot, I was forced into researching my own condition. Pesticide poisoning is one of the most under reported and misdiagnosed conditions in the US. (CDC) So here's what I've found that should be added to your report: Pesticide drift exposures in urban areas surpass incidents in Agriculture. Shocking isn't it? The data you're reading shows incidences of pesticide poisoning in agricultural areas. But the majority of pesticide poisonings are missed. They aren't reported as a pesticide poisoning because only 2% of Doctors receive any training in environmental medicine and fewer in recognizing toxin induced conditions. Many people in urban settings generously use 'weed and feed' products (2,4-D), weed killers (2,4-D & glysophate), vegetable and flower dust (carbaryl), ant and roach sprays and baits, house and garden insect killers, (organophasphates). They use them with the nonchalance of using Elmer's white glue. But these substances are poisons. They get sick and go to the doctor and never put their symptoms together with their pesticide use. The majority of the time, neither does the doctor. The other thing that people don't realize is that their little bit of pesticide use is accumulative with each of their neighbors... Take reserch on carbaryl: one study showed toxic levels of carbaryl drift seven miles outside an urban area, where no carabaryl had been applied. They traced the drift back to urban use... Pesticides are a Public Policy issue. Everyone is being exposed to toxic levels of drift from indoor and outdoor use. We need to thoroughly examine all the aspects of this issue. David Pimmental, Ph.D. Entomologist from Cornell University says that only 2% of applied pesticide reaches it's intended target. 98% goes into the environment. I don't believe that any of us can afford this kind of careless poisoning of our environment.
Beve11's picture
Beve11 /
Hi, First, I want to apologize for my poor English, as I am a French speaker, so some of my terms might not be exact, but I hope the idea will be understandable! I'm quite happy to read this article because it strucked me lately that EWG Dirty Dozen list, though really interesting from the Consummer Health perspective, gives people a false impression of sustainable consumption. In fact, many people will think that if there is less pesticides in the fruit they eat, it is because there are less pesticides use to grow them, not taking any consideration about many other criterias. For instance, is it a fruit that we peel before eating like bananas or fruit that we eat with the peel. Or is it a vegetable that we eat the leaves or the fruits. So my question is: do you happen to know any list, similiar to the Dirty Dozen and Clean 15 (and understandable from the average men and women) but that has a more environmental and farmers health standpoint? I've been looking for one for a long time! Thank you,