Saturday, June 6, 2015

GMOs and the Law of Unintended Consequences

Bt Delta Endotoxin protein sequence

[Food and Technology]  [Business and Politics]

Let’s begin by narrowing the discussion to just a single GMO field crop (from the likes of Bt-potatoes, Bt-corn, Bt-sweet corn, Roundup Ready soybeans, Roundup Ready Corn, and Liberty Link corn) and the ‘unintended consequences’ associated with its widespread use.


Bt-corn is a plant that has been genetically modified through the addition of a small amount of genetic material from other organisms through molecular techniques. In this case, the genetic material gives the plant with the genetic traits to provide protection from pests.

A donor organism may be a bacterium, fungus or even another plant. In the case of Bt-corn, the donor organism is a naturally occurring soil bacterium, Bacillus thuringiensis, and the gene of interest produces a protein that kills Lepidoptera larvae (caterpillars), in particular, European corn borer. This protein is called the Bt delta endotoxin. Growers use Bt-corn as an alternative to spraying insecticides for control of European and southwestern corn borer.

Bt-corn rapidly came into popularity among U.S. farmers after first being planted commercially in 1996. Within a few years, populations of rootworms and corn borers had plummeted across the midwest. Yields rose and farmers reduced their use of conventional insecticides that cause more ecological damage than the Bt delta endotoxin.

Without digressing into the hotly debated arguments regarding ‘substantial equivalence , the FDA, and whether BT-corn has any adverse affects on the humans that consume it, let’s just touch on a couple of facts and then return to the central focus of this article:
  • Approximately 90% of soybeans, maize, cotton and sugar beets grown in the US have been genetically modified to produce a protein that kills common insect pests or to make them highly tolerant of an herbicide used to control weeds.
  • Corn has found its way into so much of our food and in ways that you might not evern imagine (estimated to be 60%-70% of our food products). The list of foods extend way beyond the obvious.  For example, just think how widely high fructose corn syrup is used.  For a provocative list of food products, check here.
Un-intended Consequences

Just a few years later, by the turn of the millennium, scientists who study the evolution of insecticide resistance were warning of imminent problems. Any rootworm that could survive Bt exposures would have a wide-open field in which to reproduce; unless the crop was carefully managed, resistance would quickly emerge.

These scientists strongly urged effective management that consisted of refuges set aside and planted with non-Bt corn. Within these fields, rootworms would remain susceptible to the Bt toxin. By mating with any Bt-resistant worms that chanced to evolve in neighboring fields, they would prevent resistance from building up in the gene pool.

However, when an advisory panel convened in 2002 by the EPA suggested that a full 50 percent of each corn farmer’s fields be devoted to these non-Bt refuges, these recommendations were resisted by seed companies and eventually the EPA itself, which set voluntary refuge guidelines at between 5 and 20 percent. Many farmers did not even follow those recommendations.

By 2009, there were reports of extensive rootworm damage in Bt cornfields in northeast Iowa. Populations there had become resistant to one of the three Bt corn varieties. (Each variety produces a different type of Bt toxin.) This resistance was described in a 2011 study At the same time, additional reports of root worm-damaged Bt-corn came in from parts of Illinois, Minnesota, Nebraska and South Dakota. These didn’t represent a single outbreak, but rather the emergence, again and again, of resistance. 

Further Consequences to Human Health

Bt delta endotoxin in our food, via Bt-corn, is also cited as one of many causes of LGS (leaky gut syndrome).  The human gastrointestinal wall is only one cell thick and this toxin is thought to be one of the causes for microscopic holes that allow undigested food to pass into the abdominal cavity. This event compromises the liver, the lymphatic system, and the immune response including the endocrine system.

This is commonly called auto-immune disease.  It is often the primary cause of the following common conditions: asthma, food allergies, chronic sinusitis, eczema, urticaria, migraine, irritable bowel, fungal disorders, fibromyalgia, and inflammatory joint disorders including rheumatoid arthritis are just a few of the diseases that can originate with leaky gut. It also contributes to PMS, uterine fibroid, and breast fibroid.


You could conclude that farmers were enjoying the benefits of a higher crop yield and did not want to suffer any reduction in that yield by adopting the recommendation to plant  50 percent non-B-corn. The seed companies did not want reduce their profits by supporting a split of Bt and Non-Bt-corn.  The EPA is totally ineffective, and more of a tool of the biotech and agrochemical companies.  As a result, in just over 10 years, we have facilitated the evolution of a new Bt resistant pest.

The law of unintended consequences will play out in various ways that we can not even imagine. It might be something very similar to what has happened with Bt-corn, such as what is occurring right now with RoundUp ready GMO crops that are starting to see the emergence of a Roundup resistant ‘super weed’. Or might be something we have not even considered, such as the result of our exposure to various GMOs and GMO related substances such as residual RoundUp that may spawn and new super-cancer.  I am not trying to inflame ungrounded paranoia, but on the other hand, we really have no idea what we are doing, and at least in the US, we seem to be awfully blasé about letting our citizens serve as guinea pigs for foods and farming practices that have only undergone limited and short-term testing in the name of higher production and profits.

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