Monday, December 16, 2013

Basic Introduction to GMO and Roundup

What is all the controversy around GMO foods, and what does it mean for us? Thanks to Regine, with help from Peter and Sue, for compiling information from Dr. Don Huber’s talks on Nov 11 and 12, 2013 in Tallahassee FL.  Dr. Huber is professor emeritus of plant pathology at Purdue University. 

RĂ©gine Maligne  - Dec 16,  2013

What you need to read before further reading on GMO.


Why read this?
What is the U.S. crop situation?
A convenient herbicide?
How does Roundup/Glyphosate work?
What is a Genetically Modified Organism (GMO)?  What is plant genetic engineering about? 

In a nutshell

Why is it time to get educated about Genetically Engineered (GE) crops? 

These crops dominate our modern food supply and may be affecting our health without us knowing it: not only because they are nutrient-deficient but also because they are full of herbicides and insecticides.  We now have enough studies showing the damage to our plants and to our health.

The situation in the U.S.

75% of the crops approved by the FDA have been genetically engineered, either to survive being sprayed by an herbicide (called Roundup) or to contain an insecticide Bt toxin, or both.

In 1995 the FDA approved GE corn, soy, cotton, canola, potato, squash and tomato food crops, and the amount of GE crops since then has steadily been increasing. This means that an increasing amount of herbicides and insecticides absorbed by these crops gets into our food chain.  135 published peer-reviewed studies show the detrimental effect those GE crops have on animal health and the environment.

How much of the food is contaminated? In 2012 USDA estimates of US grown GE crops are as follows:

- 93% of all soy (goes in your cooking oil, tofu, soy sauce, lecithin, soy nuts, soy milk, infant formula, cereal products, flour, soy protein, mayonnaise, salad dressing),

- 88% of the corn (goes in cooking oil, corn products, corn, corn syrup)

- 94% of the cotton (cottonseed oil used for fried foods).

This dominance of commercially grown crops is why most U.S. residents are consuming large quantities of Genetically Modified Organisms (GMOs) in their food. Chances are that your favorite potato or corn chip has been genetically engineered; and you get a double dose of GMO if it has been fried in canola, corn, cottonseed, or soy oil.

How did we get there? To simplify agriculture, herbicide manufacturers had the idea of ‘creating’ by genetic engineering crops that can withstand direct applications of Roundup herbicide or contain an insecticide Bt toxin, or both.  The use of Roundup has gone up steadily since 1994. Let’s understand how it works to be able to grasp how it threatens our health.

Key learning Points:

- GE crops are the majority of what is grown in the US.

- Through GE crops, herbicides and insecticides have gradually and steadily made their way onto our plate since 1994.

- No study longer than 3 months has been carried out that can prove that GE crops have no adverse effect on health. In fact, 135 published studies show the possibility of  adverse risks.

A convenient herbicide?

Roundup (used since 1974) has become the herbicide everyone knows to use for its effectiveness and ease of use: it kills a plant when it is sprayed on its leaves (unlike other herbicides that are absorbed by the roots and can drift in the soil and kill your flowers when you just wanted to kill the weeds in your driveway).

Roundup is well known to the home owner and is also used extensively in agriculture:

1) At crop start: Roundup is used to kill the weeds to prepare a field for sowing (it is called ‘burn down’ in agricultural jargon).   Many people, like my mother in France, have used it in spring to ‘clean the garden’ since Roundup was first falsely advertised as biodegradable and not harmful for future crops.

2) During crop growth: If the crop is RoundupReady (RR), this means that it is ‘genetically engineered’ to survive being sprayed: a whole field is sprayed with herbicide and only the weeds die. This method is considered convenient and labor-saving.

3)   At the end of a crop: For non-RR crops, Roundup is also used to kill the crop at the end of its life to hasten ripening of the seeds (Roundup is then said to be used as a ripening agent).

The active ingredient in Roundup is called Glyphosate.  How does it work and are there any health issues associated with it?

Key learning Points:

-   Roundup is heavily used by non-organic farmers.

-   To simplify weed control, some crops have been ‘designed’ by genetic engineering to survive being sprayed by Glyphosate. Soy was the first to be adapted.

-   This means that Glyphosate accumulates in the soil and in plant tissue.

How does Roundup/Glyphosate work?

Glyphosate disables the ability of the plant to get the right nutrients.  The plant weakens. It also promotes the explosion of the soil microscopic organisms (bacteria, fungi, nematodes etc) that cause plant disease.   Double whammy!

The soil holds a huge living population of micro-organisms (bacteria, fungi etc., 90% of which are still unknown): some support plant life and some produce disease.  Glyphosate happens to kill the microorganisms that promote plant life.  The disease-promoting microorganism population multiplies and becomes more virulent.  As a result, many plant diseases are now re-emerging, spreading or attacking new crops. New diseases are appearing.

It is a scenario similar to the one of humans and antibiotics - antibiotics are overused in medicine and in animal breeding. Did you know that to stop animals from getting too sick because of crowded conditions, animals are fed low-level antibiotics? This abundance of antibiotics causes super organisms to appear that are resistant to antibiotics.

In the same way, heavy continuous use of Roundup causes the soil to become toxic with super microorganisms causing disease... and super weeds.

Key learning points:

-   Glyphosate disables plant resistance to disease by suppressing the plant’s ability to get the right nutrients.

-   Glyphosate kills the good microorganisms in the soil, hence allowing the soil population of disease-causing microorganisms to explode and become more virulent.

-   A sprayed plant, weakened by its inability to get the right nutrients, dies of disease.

What is a Genetically Modified Organism (GMO) - what is plant genetic engineering about?

Here is a little reminder of what you already know even if you think you know nothing about genetics! Let’s look at ‘normal’ gene combinations: a child gets half of its genes from its mother and half from its father. This is normal sexual reproduction. It is the same with plants. Male flowers and female flowers (in some plants) supply the genes of the future plant and give it different characteristics. Traditional plant breeding selects parents that give a sweeter tomato or a resistance to some disease or other desired characteristics.

Genetic engineering refers to the process of creating GMOs.   It is what occurs when genes from a totally different species are inserted into the plant’s genetic material to create a new ‘living form’ (totally different from normal ‘sexual’ reproduction, i.e. when male and female plants or flowers from the same plant species are involved).

-   Genes from a bacteria called BT are added to a plant’s genes. This GMO plant kills insects that eat it.  There is no need to spray the crop - the plant now has a ‘built in’ weapon against leaf-eating insects. 

-   Genes are added to plants to allow them to resist being sprayed with Glyphosate (found in Roundup).  They can absorb the herbicide and not get killed.

 The same company makes Glyphosate and GMO crops.

Are you still with me? Did you realize what I just told you? The US food system since 1995 has come to be dominated by crops that are full of herbicides and plants that are also filled with insecticides (which are then passed on to us). 

Genetic Engineering is a very random process.  It is not like surgery where you delicately cut and paste, but more like a war: you bombard the plant chromosomes with the new genes until the original gene ‘team’ gets altered and gives the wanted outcome (a plant that kills leaf-eating bugs for instance).  The unknown element here is that we do not fully understand the health effects of this new life form, as it does not exist in nature. Also, once inserted, we do not know how to remove the inserted genes; the “UNDO” command does not exist.

Suchgenetic engineering’ does not happen in nature... so how does nature do it?  How does plant breeding work to select plants with given characteristics? 

The answer is hybridization (or self pollination): Two plants of the same species cross-pollinate and create another plant.  Let us take the example of zucchini and yellow crooked neck squash: they belong to the same squash species.  If both zucchini and yellow squash flower at the same time, the male flowers from one plant may end up cross-pollinating with the female flowers of the other. The resulting fruit seeds will contain the mother’s characteristics as well as the father’s.  If you have ever saved the seeds from a squash plant and then grown them the next year, you may have had the surprise of getting a fruit that has no resemblance to what you harvested the seeds from. That’s because the genetic material has been changed. To save the seeds of your zucchini squash, you have to ensure that your plant grows far away from any other member of the same species of squash.

Key learning points:

-   RoundupReady GMO crops absorb herbicides and insert them into our food chain.

-   GE crops are different from regular plants as their genetic material is artificially altered.

-   GE is a very different mechanism from plant hybridization, where two plants of the same species are used to produce a plant with new characteristics.

-   A GMO cannot be ‘undone’ - a GMO corn will cross pollinate a non GMO corn and the original corn plant is then lost (hence the term “genetic roulette”?!).

Health impact of GMO and Roundup

Here are three pointers:

-     There is a strong correlation between 33 chronic diseases and the use of GMOs and Glyphosate (They are like cigarettes: it is not the first one that kills you but continuous exposure)

-     No studies have been done showing the health effects of glyphosate AND what makes glyphosate stick to plants (a very small amount may be dangerous to anyone spraying the Roundup).  This is called synergistic toxicology.

-     Glyphosate affects not only plants but the bacteria in our intestines. How does this affect our digestion?

Well done, now you are ready for further studies on GMOs! Do not trust what I say, go and assess the situation yourself.

try this one...

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