Mark Kastel of the Cornucopia Institute responds to the Stanford study comparing conventional and organic food:
I have enjoyed a virtually exclusive organic diet for the past 30 years. But I was deeply unsettled by a September 4 New York Times article and a similar Associated Press story casting doubt on the value of an organic diet.
In terms of the extra cost and value of eating organically, I have always subscribed to the adage “pay now or pay later.” While my personal experience does not provide much in terms of a scientifically legitimate sample size, in the last 30 years, after suffering from pesticide poisoning prompted my shift to an organic diet, I have exceeded my insurance deductible only once, due to an orthopedic injury. And my doctor keeps telling me how remarkable it is that I, at age 57, have no chronic health problems and take no pharmaceuticals.
Unfortunately, the analysis done by Stanford University physicians in the articles noted above did not look “outside the box” as many organic farming and food advocates do.
They discounted many of the studies, including by the USDA, that show our conventional food supply’s nutritional content has dropped precipitously over the last 50 years. This has been attributed to the declining health of our farms’ soil, and healthy soil leads to healthy food. Organic farming’s core value is building soil fertility.
Furthermore, there are many externalities that impart risk on us as individuals and as a society, which the physicians failed to look at. For example, eating organic food protects us all from exposure to agrichemicals contaminating our water and air.
Additionally, genetically modified organisms (GMOs) have become ubiquitous in processed food with an estimated 80%-90% contaminated with patented genes by Monsanto and other biotechnology corporations. The use of GMOs is prohibited in organics.
Interestingly, there have been virtually no long-term studies on human health impacts of ingesting GMOs, although many laboratory animal and livestock studies have led to disturbing conclusions. The best way to operate using the “precautionary principle,” as European regulators mandate, is to eat a certified organic diet.
Current research now indicates that some of Monsanto’s genes are passing through the placenta into human fetuses and into the bloodstreams of adults and children. Organics is a way to prevent your children from becoming human lab rats testing genetically engineered bovine growth hormone (rBGH) or a myriad of other novel life forms.
Stanford researchers, cited in the recent press accounts, dismissed statistically significant differences between agrichemical (pesticide, herbicide, fungicide, etc.) contamination in conventional and organic food.
The researchers might trust the FDA to set ” safe levels of toxic and carcinogenic chemicals in the food we serve our families but many parents have decided to set a lower threshold close zero as possible. even doctors at stanford confirm demonstrably pesticide contamination organic food.
In supporting this cautious approach, there is a growing body of scientific literature that suggests it’s not just the gross level of toxic contamination that pesticides present but rather minute amounts of these toxins can act as endocrine disruptors, or mimickers, sometimes triggering catastrophic and lifelong abnormalities in fetuses and developing children.
Is it worth experimenting with the health of future generations when we know that there is a demonstrated safe alternative—organic food?
To illustrate the difference, researchers at the University of Washington published a paper in Environmental Health Perspectives that documented a tremendous drop in organophosphate pesticide contamination, in the urine of children, after just three days on an organic diet. This is hard science that did sway the Stanford investigation’s conclusion.
Scientists have also recognized that we must take into consideration the disproportionate quantities of food that children consume relative to their body weight, especially of certain fruits and vegetables that have been found to be highly contaminated with synthetic chemicals. Furthermore, their study failed to look at the cumulative effects of contamination in many different food items in one’s diet. Again, children, for developmental reasons, are especially at risk.
Both the New York Times and AP stories did touch on a number of advantages, like lower levels of contamination from antibiotic-resistant pathogens. But that was also dismissed by stating that these could be ” killed during cooking. however we know that inadequate cooking does take place and cross-contamination can easily occur in residential kitchens. so again I pose the question how many potentially lethal antibiotic-resistant organisms do you want to bring into your home?
Although there is conflicting science on whether or not organic food is truly nutritionally superior, there is no doubt that in terms of many parameters, organic food is demonstrably safer.
I will stick with the diet that concentrates on fresh, local, more flavorful food that’s produced without synthetic fertilizers, pesticides, antibiotics, hormones and genetically modified organisms. And I for one think I’m getting a good value for my own health, while at the same time supporting good environmental stewardship and economic justice for family farmers.
Mark A. Kastel
Senior Farm Policy Analyst
The Cornucopia Institute
Tom Philpott of Mother Jones questions the Stanford study’s assumptions:
Is organic food little more than a trumped-up marketing scheme, another way for affluent consumers to waste money? A just-released paper by Stanford researchers—and the reaction to it by the media—suggests as much. (Abstract here; I have a copy of the full study, but can’t upload it for copyright reasons.)
“Stanford Scientists Cast Doubt on Advantages of Organic Meat and Produce,” declared a New York Times headline. “Organic food hardly healthier, study suggests,” announced CBS News. “Is organic healthier? Study says not so much, but it’s key reason consumers buy,” The Washington Post grumbled.
In reality, though, the study in some places makes a strong case for organic—though you’d barely know it from the language the authors use. And in places where it finds organic wanting, key information gets left out. To assess the state of science on organic food and its health benefits, the authors performed what’s known among academics as a “meta-analysis”—they gathered all the research papers they could find on the topic dating back decades, eliminated ones that didn’t meet their criteria for scientific rigor, and summarized the results.
In another post I’ll get to the question of nutritional benefits—the idea, expressed by the Stanford authors, that organic and conventional foods are roughly equivalent in terms of vitamins and other nutrients. What I want to discuss now is the problem of pesticide exposure, and why I think the Stanford researchers are underestimating the risks.
In short, the authors’ findings confirm what the Environmental Working Group, crunching USDA data, has been telling us for years: that organic fruits and vegetables harbor significantly fewer pesticide residues than their chemically grown peers. Summing up the evidence of the studies they looked at, the Stanford researchers find what they call a 30 percent “risk difference” between organic and conventional food—which to the mind not trained in statistics, sounds like organic foods carry 30 percent less risk of exposing you to pesticides. And they immediately undercut that finding by noting that the pesticide traces found in both organic and conventional food tend to be at levels lower than the Environmental Protection Agency’s maximum allowed limits. Takeaway: Conventional produce carries trivially small levels of pesticides, and you might as well save your money and forget organic.
What’s wrong with this comforting picture?
1. Conventional produce is much worse than organic on the pesticide-exposure question than the 30 percent number suggests. That’s what Chuck Benbrook of the Organic Center shows in a detailed critique of the study. To get the 30 percent number, the authors used an odd statistical construct they call “risk difference.” By their method, if 5 percent of organic vegetables contain at least one pesticide trace and 35 percent of conventional vegetables contain at least one trace, then the “risk difference” is 30 percent (35 minus 5). But that’s a silly way of thinking about it, because there’s a much greater difference between those numbers than “30 percent” suggests. Crunching the authors’ own raw data, Benbrook finds “an overall 81% lower risk or incidence of one or more pesticide residues in the organic samples compared to the conventional samples.”
But even that doesn’t get to the full extent of the study’s underestimation, since:
2. To arrive at their “risk difference” metric, the authors didn’t distinguish between a single pesticide trace and multiple traces; or between light traces and heavier traces. For their purposes, an organic apple carrying a tiny residue of a relatively innocuous pesticide is equivalent to a conventional apple containing a cocktail of several relatively toxic pesticides. Here’s Benbrook on why that’s silly:
a) most residues in organic food occur at much lower levels than in conventional food, b) residues are not as likely in organic foods, c) multiple residues in a single sample are rare in organic food but common in conventional produce, and d) high-risk pesticides rarely appear as residues in organic food, and when they do, the levels are usually much lower than those found in conventional food (especially the levels in imported produce).
Now, the authors might reply that all of this is trivial, because the traces that researchers find on produce, whether conventional or organic, almost always come in at levels below the EPA’s safety threshold. But:
3. This ignores a growing body of research that pregnant women’s fetuses can be harmed at low exposures of organophosphate pesticides, as can young children.
And what’s more:
4. The authors—like the EPA itself—ignore the “cocktail effect” of exposure to several pesticides, say, from a single apple. As Environmental Working Group’s analysis of USDA data shows, conventional produce like apples, blueberries, and bell peppers often carry traces of many pesticides. The EPA regulates pesticide traces only on an individual basis, disregarding possible synergistic effects. The European Commission is starting to take them more seriously. Here’s a report commissioned by the European Commission in 2009:
There is a consensus in the field of mixture toxicology that the customary chemical-by-chemical approach to risk assessment might be too simplistic. It is in danger of underestimating the risk of chemicals to human health and to the environment.
Which brings us to the fifth point:
5. We probably know more about how exposure to low levels of multiple pesticides affect amphibians than we do about how they affect people—and what our amphibious friends are telling us isn’t pretty.
In short, the Stanford study seriously underplays the benefit of going organic to avoid pesticide traces, especially for vulnerable populations like pregnant women and kids. In a future post, I’ll show why it does the same for exposure to antibiotic-resistant pathogens in meat, and doesn’t give organic its due with regard to nutritional benefits.