Aug 25 2015

Anti-GMO in the NEJM

A recent commentary published in the New England Journal of Medicine (NEJM) by Philip J. Landrigan and Charles Benbrook has sparked some controversy. Landrigan and Benbrook are publishing in a medical journal because they claim the issue of genetically modified organisms (GMOs) is a public health issue. They use extremely strained logic and misrepresentation to make their point, however.

Equating GMOs with Herbicides.

The primary logical flaw in their argument is their attempt to equate GMOs with the use of herbicides. They write:

Herbicide resistance is the main characteristic that the biotechnology industry has chosen to introduce into plants.


The first of the two developments that raise fresh concerns about the safety of GM crops is a 2014 decision by the Environmental Protection Agency (EPA) to approve Enlist Duo, a new combination herbicide comprising glyphosate plus 2,4-D. Enlist Duo was formulated to combat herbicide resistance.

The authors also acknowledge that:

” genetically engineered crops can increase yields, thrive when irrigated with salty water, or produce fruits and vegetables resistant to mold and rot.”

That is actually a short list – there are also genetic traits to resist crop viruses, to enhance nutrition, and reduce toxins. GM technology is a technique that can be used to introduce a variety of traits. It is not inherently tied to herbicide resistance.

And yet Landrigan and Benbrook want to paint all GMOs with the broad brush of herbicides, as if they are the same thing. And again, they even acknowledge the facts that render their entire premise absurd:

The National Academy of Sciences has twice reviewed the safety of GM crops — in 2000 and 2004. Those reviews, which focused almost entirely on the genetic aspects of biotechnology, concluded that GM crops pose no unique hazards to human health.

Questions about GM technology should focus on GM technology, not the consequences of one particular application of the technology. Their argument is the equivalent of opposing metallurgy because the technology is used to make bullets, or all of pharmacology because some antibiotics have been overused resulting in bacterial resistance.

They do this because they cannot argue that the technology itself is not safe. No specific health issues have arisen.

Misrepresenting Risk

The NAS did mention that introducing novel proteins into food has the potential to introduce new allergens and toxins and recommended appropriate testing and monitoring, to which Landrigan and Benbrook write:

Both reports recommended development of new risk-assessment tools and postmarketing surveillance. Those recommendations have largely gone unheeded.

This is not a fair assessment. The process of creating GMOs specifically filters out new potential toxins and allergens. Toxins and allergenic proteins tends to have peptide sequences in common that allow them to survive stomach acid and digestive enzymes sufficiently intact to get absorbed and cause allergy or toxicity. Any genes added to GMO will produce known peptide sequences which are systematically checked against known toxins and allergens.

This system works, at least so far. There has not been a single case of allergy to a GMO crop. This is a better safety record than crops produced through traditional breeding, hybrids or mutation farming.

Kevin Bonham, responding to the claim that GMOs pose an allergy risk, writes in the Scientific American:

This is patently false – genetic engineering techniques allow us to precisely add genesof known structure and function to crops. It would in principle be possible to engineer corn that expresses anthrax toxin, or introduce peanut allergens into soybeans, but this would have to be by malicious intent of the scientists, not some accident. We know how genes work, and we know what kind of protein an individual gene will make.

What are the risks of herbicides?

Landrigan and Benbrook falsely equate GMOs with herbicides, and falsely create alarm about non-existent risks of GMO, while downplaying the fact that there is no specific risk to the technology itself. Are their concerns about herbicides legitimate, however? Yes and no.

Certainly we need to be cautious about agricultural technology, especially any substances used in farming that will end up on our food. Landrigan and Benbrook claim that use of herbicide resistant GM crops has led to an increase in herbicide use, specifically of herbicides (glyphosate and now 2,4-D) that are listed as a probable and possible carcinogen respectively. This, however, is misleading.

Check out the reaction from scientists at the Science Media Center. This is a good neutral source that gets reactions from experts in the field to items in the news. They include great criticism of the NEJM article, including this:

Prof. Anthony Trewavas FRS, Emeritus Professor of Cell Biology at the University of Edinburgh, said:
“This latter organisation points out that the WHO cancer committee claims are based on very few documents, mainly on animals and with limited evidence in humans and of course ignore the importance of dose. This same WHO cancer committee also placed hairdressing, art glass, night shifts, tea bag manufacturing and grapefruit juice in the same ‘probably carcinogenic’ class along with emissions from frying food but not those from grilled food.”

The bigger point here is that Landrigan and Benbrook exaggerate the risks of glyphosate and 2,4,D, and they ignore the fact that glyphosate replaced far more toxic herbicides and therefore glyphosate resistant crops reduced the overall toxic potential of herbicides in farming. Further, toxicity data must be put into the context of real world exposures, which is what the EPA does. Careful monitoring by the EPA indicates that herbicide residues are orders of magnitude below toxic levels, even for children, despite the false claims of the authors.

Further still, they compare herbicide use today with five years ago, because recent glyphosate resistance has resulted in increased applications. But they ignore the fact that total herbicide use has not increased compared to pre-GMO level. Farmers were using herbicides (and more toxic herbicides) long before GMOs – another reason that conflating GMO technology and herbicide use if fallacious.

There is a legitimate concern with weeds developing herbicide resistance, just as there is a legitimate concern with bacteria developing antibiotic resistance. This gets to how herbicides (and antibiotics) are used. Over-reliance on a single method of pest control in massive farming is always going to be problematic. This is why there is a push for integrated pest management, to use a variety of methods that limit resistance. None of this has anything directly to do with the safety of GM technology.

Conflicts of Interest

Many commenters were upset at the fact that Benbrook disclosed no conflicts of interest. Meanwhile:

Benbrook was formerly the research director of The Organic Center, which is funded by the organic industry and is now officially part of the Organic Trade Association. His three year affiliation with the Center for Sustaining Agriculture and Natural Resources (CSANR) at Washington State University (WSU), which was funded entirely by organic industry contributions, ended on May 15, 2015 when his contract was not extended.

In the anti-GMO narrative, having a connection (no matter how tenuous) to a biotech company is a fatal conflict of interest, while have a connection to the organic food industry, no matter how close, is not a conflict at all.

Benbrook is pro-organic (an industry insider) and anti-GMO. This is a conflict of interest. This does not mean that his arguments are wrong, but it is now considered acceptable practice to disclose any such conflicts for the sake of transparency so that the reader can decide.


Landrigan and Benbrook conclude:

Finally, we believe the time has come to revisit the United States’ reluctance to label GM foods. Labeling will deliver multiple benefits. It is essential for tracking emergence of novel food allergies and assessing effects of chemical herbicides applied to GM crops. It would respect the wishes of a growing number of consumers who insist they have a right to know what foods they are buying and how they were produced. And the argument that there is nothing new about genetic rearrangement misses the point that GM crops are now the agricultural products most heavily treated with herbicides and that two of these herbicides may pose risks of cancer. We hope, in light of this new information, that the FDA will reconsider labeling of GM foods and couple it with adequately funded, long-term postmarketing surveillance.

Each one of their claims here is wrong or highly problematic. Labeling all GMOs will have no benefit, but instead will produce consumer confusion. Ironically the authors specifically contribute to that confusion and demonstrate exactly why it will happen.

They desperately try to conflate GM technology with herbicide use, and then hype the health risk of those herbicides. A “GMO” label, however, will tell the consumer precisely nothing about the risks of the food they are buying. A GM potato that produces less acrylamide (which may actually be carcinogenic) would receive the same GMO label as herbicide resistant soy. If the authors have their way, the average consumer would see the “GMO” label as if it means “laced with toxic herbicides.”

Many GMO traits have nothing to do with herbicides, and crops that are not GMOs may still have been treated with herbicides. The label does not actually tell the consumer anything about risk.

In their misleading piece, Landrigan and Benbrook actually inadvertently make a strong argument against labeling by demonstrating how it will be used to confuse and misinform.

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