A few days ago, Jon Entine posted a story on Slate.com reporting that Caitlin Shetterly’s feature in Elle magazine on genetically engineered (GE) corn (AKA genetically modified, or GM, corn) “just doesn’t withstand the critical scrutiny of science.”
But Entine’s post itself fails to withstand critical scrutiny. He botched his story about GE foods and human allergens on several fronts.
First, any examination of a possible relationship between GE crops and human allergens should include a discussion of StarLink™ corn and Entine’s piece doesn’t.
StarLink was a GE corn that was not approved for human consumption and yet ended up in taco shells and other corn products on U.S. grocery shelves which in turn led to a massive recall of corn products, investigations into reports of humans with allergic reactions, and federal monitoring of U.S. corn crops for levels of the offending protein over nearly eight years.
StarLink was genetically engineered to produce an insecticidal protein from a strain of Bacillus thuringiensis (Bt) bacteria. Other varieties of “Bt corn,” which save farmers from spraying certain insecticides because these varieties make their own, had been commercialized before StarLink and plenty of additional Bt corn varieties have been commercialized since. In fact, the vast majority of corn grown in the U.S. today is Bt corn, including fresh corn available in supermarkets. (And FYI, in almost all cases, the Bt insecticide is produced in every cell in every kernel of every ear of Bt corn.)
Before they can be commercialized in the U.S., Bt corn varieties (or any other GE crops that make their own pesticides) must go through an approval process with the U.S. Environmental Protection Agency (EPA), a process that includes testing each Bt protein for whether it might cause human allergies. Prior to StarLink corn, the Bt protein in every Bt corn variety passed the various tests the EPA ran for allergenicity with flying colors; the Bt protein in StarLink failed them all.
Behaving like a human allergen in the tests didn’t necessarily mean that the StarLink Bt protein actually was a human allergen. Still, the EPA–wisely in my opinion–decided to be cautious and did not allow StarLink to be commercialized for human food. The agency went on to make what I consider a less wise decision, on the other hand, when it approved StarLink for animal consumption. One reason that decision was unwise is that corn is wind-pollinated. The subsequent contamination of corn meant for human consumption was essentially inevitable.
In the aftermath of StarLink corn contaminating human foods, experts working with the U.S. regulatory agencies concluded that the Bt protein in that GE corn variety had “a medium probability of being a potential allergen” and that the level estimated to be in human food presented a “low probability to sensitize some individuals” to the protein (and thereby possibly cause them to become allergic to it). The U.S. regulatory agencies were concerned enough about the allergenicity of StarLink corn that levels of the StarLink Bt protein in corn ear-marked for human food were monitored until about five years ago. The EPA’s final white paper on exposure to and any potential risk from the StarLink Bt protein was filed in March of 2008.
As I hope I’ve made obvious by now, any scientific scrutiny of the topic of GE corn and human allergies should include a telling of the StarLink corn story. (And it isn’t difficult to find; StarLink corn came up in my first 25 google hits for “genetically modified corn allergen.”) StarLink corn is at least a reminder that the results of genetically engineering a plant can be unexpected and undesired and it therefore remains prudent to use this powerful tool of agricultural biotechnology cautiously, especially as it is now being used to produce GE products that are more varied and complex than Bt corn. At most?…StarLink corn could actually represent an example of how a unique human allergen might have been created through the process of genetic engineering.
Entine’s piece also is inaccurate in its description of what is (or is not) required by FDA of producers of new GE foods, fails to mention that genetic engineering is also, in fact, a mutagenic process, and completely ignores the issue of labeling GE foods, without which tracking down any potential allergens or toxins associated with them would be much more difficult. (To read previous posts I’ve written on these topics, please follow the links I’ve added to the previous sentence.) In short, Entine’s post certainly didn’t “set the record straight” (a request he made of Elle) and wasn’t anything like the “even-handed analysis of the costs and benefits associated with adopting” genetic engineering that he mentioned Amy Harmon’s New York Times article on the plight of the orange industry in Florida had been praised for.
Too bad. What the debate over GE foods could really use is both more even-handedness and accurate record-setting.
I wish as many people would read this as read Entine’s. Ironic that he affiliates himself with “Genetic Literacy” as he is arguably the most flagrantly misinformed writer on anything genetic (like his juvenile and scientifically silly book on black athletes). But he’s doing this on purpose: he is the Ann Coulter of science writing, except less original.
I watched all of the interviews yesterday with Stacy Malkan. I truly appreciated every perspective, including yours. Wish I had run across your blog last summer. I’ve had some very intense conversations about the GMO issue (whether to label; whether to adopt precautionary principle) since I became more interested in this topic during the summer of 2012, when I realized I needed to learn more in order to make an informed ballot choice re prop 37. The pro-GMO arguments I encounter are: (1) GMOs have undergone rigorous safety testing; (2) no proof that biotech industry is intimidating researchers who dispute their claims or that they restrict access to their studies; (3) no link between complicated health problems & GMOs; (4) increase in use of some agricultural chemicals is irrelevant because GE technology has also reduced use of others; (5) absolutely no data to support wild accusations that GMOs that have GE pesticide resistance in any way transfer that capability to consumers of those GMOs; (6) Golden Rice is a terrific idea that should be unleashed freely in order to feed malnourished communities; (7) global climate change dictates that we need GE technology in order to find new ways to grow food, given the extreme changes we are seeing in climate around the world; (8) 2,4-D is not the toxic problem it’s purported to be – the truly toxic part of Agent Orange has been eliminated from this chemical concoction; (9) absolutely no data that indicates that biotech industry drives university research efforts & outcomes; (10) chemical drift has always been a problem – GE farming is not the cause of this problem; (11) absolutely no data that shows that neonics are responsible for CCD, or that GE farming in any way is responsible for this problem; (12) & more. I’m hoping you might address some of these issues in your blog in the upcoming months. I’ll be watching for insights. Meanwhile, I have tried to find consumer-friendly reports about agricultural pesticide drift in California, & if/how GE farming is adding meaningfully to that problem. Can you provide me with any direction? Thanks again for participating in yesterday’s line-up.
I will be addressing many of these issues on this blog in the coming months; thanks for your interest.
As to information on agricultural pesticide drift in California, I suggest that you check out the Pesticide Action Network’s web site: http://www.panna.org and/or contact another of the “GMOs: What You Need to Know” speakers, Dr. Marcia Ishii-Eiteman, who works for that organization and is an expert on pesticides.
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