New GM Technology Allows Crops To Just Say No To Dangerous Toxins

Contaminated maize in Africa - Image from International Institute of Tropical Agriculture

(This article originally appeared on Forbes on 3/21/17)

There has been a breakthrough on a way to reduce the risk of a major form of cancer in the developing world. It involves corn genetically modified to "just say no" to the production of a carcinogenic toxin in its grain.

Have you heard of Aflatoxin? It is a major risk factor for cancer in the developing world.  Aflatoxin is a natural chemical produced by a fungus. It is a highly toxic and is a very potent carcinogen in animal studies. Those of us in the developed world are fortunate in that a number of safeguards keep aflatoxin out of our animal feed and human food supplies. Unfortunately, in the developing world, people are not so well protected. In those regions aflatoxin contaminated foods are responsible for many poisonings, and high cancer rates. Researchers in Arizona have recently published a paper about a biotech crop breakthrough that could dramatically improve that situation.

Aflatoxins are chemicals produced by certain fungi that infect food crops (Aspergillus flavus, Aspergillus parasiticus). The biggest developing world risks are with maize (corn), and groundnuts (peanuts) - staple, subsistence crops in parts of Africa and Asia. When insect feeding damages crops and/or through drought stress, they are most susceptible to infection by these fungi. The infections can continue to develop after harvest, particularly under less than ideal storage conditions.

Maize (corn) in Africa (Image by Kate Holt/AusAID)

In an article published in the prestigious journal, Science Advances, five scientists from public institutions in Arizona described how they genetically engineered corn to prevent its contamination by aflatoxin. For this article I spoke with Dr. Monica Schmidt of the University of Arizona. Schmidt’s team engineered the corn to make three small RNA molecules designed to specifically bind to parts of a particular RNA produced by the fungus. These small RNAs made in the kernel cells are able to move from the corn into the invading fungus. Once there, they trigger a mechanism in the fungus cells that blocks the production of a key enzyme required by Aspergillus to make aflatoxins. Because this approach involves three separate bits of targeting RNA, it is extremely unlikely that the fungus could mutate in a way to get around this blockage. The corn plants modified this way are effectively protected from contamination with aflatoxin. This kind of corn could give developing world consumers a much safer food supply.

This work was funded by the Gates Foundation, which also funds work to develop corn that is resistant to insect damage and drought. In combination with the aflatoxin protection this constitutes an ideal integrated solution for that critical crop. This is also a proof of concept for taking a similar approach with peanuts. The intention is to make this technology freely available for breeding into the local crop varieties that are best adapted to the regions in question.

What about the developed world? It would actually make a lot of sense to add this technology to the diverse toolset that we already use to keep aflatoxin out of our corn and peanuts. There are also other crops that could benefit from another protection strategy from aflatoxin – notably tree nuts like almonds, pistachios, walnuts and pecans. Aflatoxin can also be an issue in cottonseed that is used as an animal feed. The same biotech strategy may well work with other fungal toxins that can be an issue in other crops.

The world’s consumers can derive great health benefits from the further development of this technology.  This is definitely one to track and to encourage.

You are welcome to comment here and/or to email me at savage.sd@gmail.com

Why Wheat Is Like Wine

Wheat harvest on the Palouse in Idaho

(This post was originally on the Better Food Stories blog 9/26/16)

There is a term in the wine grape industry called “terrior” which celebrates the fact that fruit quality for wine making is greatly influenced by cultivar, climate and soil type.  Year-to-year differences in weather further influence the quality of specific “vintages.”  Wheat may be a humbler crop, but it is like wine in the sense that there are different classes of wheat for different end-use products and there are different regions where each type excels based on climate (wheat can be hard or soft, spring or winter, red or white, and there is a separate type called “durum” for pasta).  There are even year-to-year differences in quality.  For instance, to make an artisan bread, it is best to use flour from hard red spring wheat, that comes from the northern plains (North Dakota, Minnesota) or from the prairie provinces of Canada (e.g. Alberta and Saskatchewan).  For Asian noodles one wants a soft white winter wheat from the Pacific Northwest.  For crackers a soft red winter wheat is best from a place like Southern Illinois or Kentucky.  For pasta, a distinct type of wheat called durum is used and this is grown in Arizona and in the northern plains.

There are several important measures of wheat quality that reflect important properties of the dough, like strength and elasticity. These properties drive features, like how well the dough will rise and balance of different classes of starch, which influence the texture of baked products.  A yearly report on U.S. hard red spring wheat examines eight categories of “grading” data and eleven measure of “kernel quality.”  53% of U.S. wheat and 60% of Canadian wheat are exported around the world and purchased by customers looking for specific qualities (based on FAOStats data 2011-13). Europe is a major producer of wheat and has much higher wheat yields compared to the lower rainfall production areas in North America, but European countries still import a great deal of wheat for high quality bread and pasta and use much of their domestic production for animal feed.

As with all crops, wheat is attacked by various pests. Unlike grapes, it is possible to deal with some of the pests by breeding resistant varieties of wheat (winemakers are reluctant to accept new grape varieties preferring the traditional favorites that have been in use for hundreds of years).  A key advance in the “Green Revolution” of the 1960s was developing resistance to a particularly damaging fungal disease called “Stem Rust.”  That resistance held up for decades, but in 1999 a strain of the fungus overcame the trait, and since then wheat breeders worldwide have worked to breed a new resistance gene into all the different genetic backgrounds for the diverse wheats grown around the world.

In wet climates, wheat can be infected by many different fungal pathogens and commercial production requires the use of several protective fungicide treatments, starting with seed treatments and spaced throughout the growing season.  In drier North America, diseases are not as problematic, but do sometimes require treatments to preserve yield and quality.  If it rains during the time when the wheat is flowering, a fungus called Fusarium can infect the crop and wheat has proven to be very difficult to breed for resistance. A well timed fungicide spray can help against this disease, but that is not always possible. This particular fungus can produce a mycotoxin chemical in infected wheat kernels called Deoxynivalenol or DON.  It is also called “vomitoxin” because of the effect it has on animals that consume contaminated grain. In our food system, the consumer is well protected from exposure to such toxins, thanks to the care and expense taken on by farmers.

The global wheat industry is really made up of many distinct sub-crops, but as a whole, wheat production has been making steady progress in keeping up with growing global demand with only minimal expansion in planted areas (see graph below).  Some of that progress has been made by diminishing pest damage through a combination of breeding and crop protection agents like fungicides.  Also, a great deal of modern wheat production is in “no-till” systems where weeds are controlled with herbicides instead of by mechanical tillage.  This system greatly reduces soil erosion, lowers fuel use and leads to improved soil health and carbon sequestration.

The green part of each par shows the proportion of the increased production achieved through higher yield rather than additional planting area

So the next time that you enjoy a wheat-based product, think about the effort and risk that a wheat farmer faced, not only to produce the grain, but to produce it with the positive qualities needed and with the absence of issues like DON toxin.

Vermont-Driven GMO Labeling Could Have Troubling Unintended Consequences

This small state may soon alter the food supply for all Americans

(This post originally appeared on Forbes on 3/26/16)

Over the past week and a half, Mars, General Mills, ConAgra Foods and Kellogg announced that they had decided to start labeling whether their products contain GMOs nationwide, in compliance with a pending Vermont statute. They see this as a way to avoid the cost of maintaining multiple systems for different states.

These companies clearly state that they agree with the scientific consensus that there are no safety issues with biotechnology as it has been applied to crops. Nonetheless, many observers believe that the ultimate impact of the Vermont labeling law will be to encourage companies to seek to use more non-GMO ingredients. That would, of course, be a major victory for the organizations that have promoted labeling and who are actually quite transparent about their agenda of eliminating use of the technology all together.

However this scenario plays out, there are three interesting questions to consider.

1. Why do so many consumers say they want GMO labeling?
2. Why was anyone against labeling in the first place?
3. What might be the long-term effects of this labeling requirement on our food supply?

Why do so many consumers say they want GMO labeling?

This has much to do with how you ask the question.  The term "GMO" is a misleading title made up by anti-GMO activists in Europe in the mid 1990s.  It stands for "Genetically Modified Organism," which isn't a very good term to use since virtually every crop and animal used for food today has had its genetics dramatically modified from what ever it once was in the wild.  However, since few consumers realize this, the term "GMO" has the negative emotive effect that was intended.

The genetic modifications of these plants were vastly 

more dramatic than any modern “GMO crop”

If you use emotive language to ask people about other scary-sounding foods, you can get the same reaction. I've asked many people, "do you think cloned fruit should be labeled?" Virtually everyone says "yes!" Then I explain that all fruit is "cloned" in the sense that it is vegetatively propagated by budding or from cuttings because if you grew it from seed you wouldn't get the same variety. People have been doing this for millennia, but if I use the emotive term "cloned" I can get a "label it" response.

I also sometimes ask, "do you think that food grown with products made from animal excrement should be labeled?"  Most people again say "yes" because I used an emotive term. In that case there is a small, but finite food safety risk associated with manures and composts, but we don't label it.

In any case, after 20 years of active efforts to create fear around plant biotechnology, the label is nearly guaranteed to be seen as a negative by many consumers. Again, that is exactly what certain parties hope.

Why was anyone against labeling in the first place?

On the surface this seems like a logical question, but there were rational reasons to oppose these labels. The FDA wants to reserve the exercise of its labeling authority for things with real, documented risk issues such as food allergies, not for something like biotech crops for which extensive studies show no unique risk.  Realistically, this has become a moot point. By allowing "non-GMO" and "GMO-free" labels, consumers are already being successfully recruited to buy this next example of "non-existence" food, following trends like "gluten-free," "fat-free," "zero cholesterol" and the like.  American consumers are so used to buying food for what it is not that we don't even see the absurdity.

Much of the non-GMO labeling is for products
from crops which have no commercial biotech versions anyway

The reason that the processed food industry opposed labeling for biotech crops has to do with the costs and liabilities associated with maintaining distinct product flows in these very large scale, very low profit margin businesses. It costs money to clean out all the equipment, bins, trains and trucks used for bulk handling.

Grain harvesting equipment and later handling 

are not conducive to easy segregation

Depending on tolerances, it also opens companies up to liabilities for "adventitious presence.”  In the absence of real risk, the costs just don’t make sense. “Identity preservation” of high value crops like apples, oranges or wine grapes is far more feasible, and it is routinely done, but for issues that matter like variety, appellation etc.

What might be long-term effects of labeling on the food supply?

This really depends on whether food companies have the courage to trust their customers enough to continue to use biotech-improved items even in the face of activist pressure. Will they stand-up for their decision (as the Girl Scouts have), or will they give in and start shifting to non-GMO ingredients?

Evidence suggest that many players will take the latter path and that will mean asking farmers to forgo crop traits that they have found to be very helpful. Returning to non-biotech will also make it harder for farmers to use environmentally-sound approaches like minimum-tillage. It will increase the need to spray for insect pests once controlled by Bt traits in the crops. The cost of those non-GMO ingredients will be higher, partly because of these disadvantages, but also because of what it will take to "identity preserve" the non-GMO harvest all the way down the handling, storage and processing stream.

Of greater concern is the possibility that food companies will be tempted to source cheaper version of these non-GMO ingredients from other countries. This has happened all too often for organic.  That will open up the U.S. consumer to environmental pollutants (e.g. heavy metals) and to pesticides that have long been banned here, but which are still made and used in places like China and India.  It will also mean getting items from regions that are much less attuned to the need to detect and exclude dangerous mycotoxins from the food supply.

If Vermont ends up initiating a trend towards more non-GMO products, we should be asking participating food companies to go on record promising that they won't import the ingredients if they are available from the U.S. or other countries that enjoy a general context of sound environmental, food safety, and pesticide regulation. Without such assurances, we could have a serious case of unintended consequences.

You are welcome to comment here and/or to email me at savage.sd@gmail.com

A Curious Silence: The Environmental Working Group and Mycotoxins

The Environmental Working Group (EWG) tells us:

"The mission of the Environmental Working Group is to use the power of public information to protect public health and the environment."  

If you look at their website, a great deal of what they do involves warning people about various "toxic risks."  They publish an annual "dirty dozen" list ranking crops by pesticide residues.  They have a major effort to identify purported risks from chemicals in cosmetics and sunscreens.  They look at toxic things in drinking water and in pet food.  They have an extensive "Chemical Index" with toxicity ratings.  But there are some very important toxins about which EWG is completely silent.

The Missing Toxins

The extremely important class of toxic chemicals that is completely absent from the EWG website is Mycotoxins.  You can go to the search engine on the site and enter words like: mycotoxin, aflatoxin, fumonisin, ochratoxin, vomitoxin... and find absolutely nothing.  What makes this silence so strange is that mycotoxins are known to be some of the most dangerous substances to which people can be exposed, particularly in food.  If one of EWG's primary purposes is to "protect public health" it seems odd that they would not say one thing on their web site about this extremely well-documented risk.

Beth Hoffman, an information technology writer, raised an interesting issue today in an article in Forbes.  She was discussing the huge disparity between what government and academic scientists say about pesticide safety and what the Environmental Working Group says with its "Dirty Dozen" list.  She says, "But at its core, the argument for and against lists like the Dirty Dozen is a question of trust."

The EWG clearly distrusts the scientific/regulatory consensus.  But should consumers trust the EWG?

Should we trust an organization that either ignores or fails to recognize a real and present risk when they are telling us that there is significant risk where science says there is not?  EWG says it "provides practical information you can use to protect your family and community."  How can we trust that statement if EWG provides zero information about chemicals which are not in the "you just never know" category, but in the "clearly documented as toxic and carcinogenic" category?

What Are Mycotoxins?

Mycotoxins are potent, natural chemicals which are produced by certain fungi.  These fungi can, under various circumstances, grow on food and feed crops either while they are growing in the field, or later during the storage and/or drying of certain commodities.  The most important example is a toxin called aflatoxin which is produced by some strains of the fungi Aspergillus flavus and Aspergillus parasiticus.  These organisms can grow on things like peanuts, tree nuts, and corn.  It can also grow on hot chili's or figs while they are drying if that is done improperly.  It can occur in imported spices like nutmeg.  It has been found in imported chocolate.  It is thousands of times more toxic than most pesticides, and it is one of the most potent carcinogens known.  It is estimated that aflatoxin is the a major  cause of cancer deaths world wide.  Unfortunately, this mainly occurs in the third world, and even places like China are just now beginning  to address the issue.

Why Haven't Most People Heard of Aflatoxin or Other Mycotoxins

In the developed world, extraordinary efforts are made to keep food mycotoxin levels in general, and aflatoxin levels in particular, low enough to make our food safe.  The system works well enough that it does not come to the public attention very often.  This success is based on the same sort of science-based regulation and testing that are designed to insure that pesticide usage is safe.  The system of mycotoxin exclusion generally does a great job, but occasionally something slips through - mostly incidents involving pet foods or imported products from regions of the world that don't have adequate safety practices in place.

Just as an example, nut crops like peanuts and almonds can potentially become contaminated with aflatoxin, usually because of insect damage.  In our food system, the individual, shelled nuts that go into something like peanut butter or roasted almonds are put one-by-one through a light-based screening process to reject any individual nut with even the possibility of contamination.  Peanuts and other nuts sold in-the-shell cannot be screened to that degree.  EWG could instruct consumers to avoid in-the-shell nuts to protect their family. It has also been shown that eating green plants like spinach gives us chlorophyll which can bind aflatoxin in the gut so that it never gets into our blood stream.  EWG could recommend that one eats a salad with peanut butter sandwiches just to be safe.  EWG could talk about which imported foods might be most likely to have aflatoxin.  These examples would be practical guidance about real risks.  On such issues, the EWG has long been silent.   Contrast this with the proactive efforts by the Bill and Melinda Gates Foundation to address mycotoxin issues in the third world.  Yet this major oversight is not the only reason to distrust EWG.

A Serious Issues With the Way That EWG Does Its Analysis

An analogy might be helpful here.  Domesticated dogs come in a huge range of sizes from tiny Chihuahuas to huge Mastiffs.   They also come in a huge variety of personalities, from breeds which you could easily trust with a baby to those which have been bred for aggressiveness and which have been known to maim and kill people.  If anti-dog activists were to propose that any dog should be avoided and that people should move to towns that exclude all dogs, most people would dismiss the idea as ridiculous.  This is; however, directly analogous to what EWG does with pesticide residue data and their "solution" of buying organic.  The amounts of pesticides that the USDA finds on foods in its residue testing program can vary by 1000-fold or more - actually much more than the range of dog sizes.  The intrinsic properties of the different chemicals that are detected also differ even more than the differences between aggressiveness in breeds of dogs.  Yet what EWG does when it makes its dirty dozen list is to treat every residue detection the same.  This is just like our fictitious anti-dog activist who says that all dogs represent a equivalent risk, or that you just never know about any dog.  Why should anyone trust this method to analyze risk?

Beth, the Forbes writer, gives indications that she tends to distrust the scientific/regulatory consensus.  I wonder if she has thought about whether she should trust the EWG? Do you trust an organization uses a seriously over-simplified analysis of one category of chemicals while ignoring toxins of far greater concern?  Or might it make more sense to trust science backed up by government and academic scrutiny?

You can comment here and/or you are welcome to email me as savage.sd@gmail.com.

Aflatoxin contaminated groundnut image from IITA Image Library