Monday, October 20, 2014


Should We be Concerned about Genetic Modification of Our Food?Knowledge of the presence of genetically modified organisms (GMOs) in our food supply is increasingly coming into the awareness of the American public. As this is happening, the question of the safety of ingesting genetically engineered (GE) products on a regular basis is often a concern. In truth, we’ve been consuming GE food products, often times unknowingly, for a period of 20 years.(4) It is estimated that 93% of all soybeans and 88% of all corn planted in 2012 were genetically engineered.(4) So, unless you’ve been extremely vigilant, you’ve been eating GMOs and you’ve probably been doing it for quite a while. But, before we get into the issue of safety, let’s back up a minute for those who aren’t aware of what GMOs are.

The Process of Genetic Engineering
Genetically modified organisms are produced by taking a gene from one plant or animal species and inserting it into another plant or animal species. Genes provide a map for organisms to make proteins. Proteins can serve various functions within a cell such as providing structure or movement within a cell, acting as enzymes (catalyzing chemical reactions) or as signaling molecules. The idea of genetic engineering is that by inserting new genes into an organism we can alter how that organism interacts with the environment by altering cellular functions. New genes can be added to plants for a number of reasons. They may improve drought resistance, alter nutrient content, produce natural pesticides or, most commonly, provide resistance to herbicides.
The Safety of Genetic Engineering
The current method of genetic engineering assumes that inserting one particular gene into an organism is going to lead to the production of one new protein by that organism. Unfortunately, this is not an accurate model of how living organisms work. Here’s why. The human genome contains about 20,000 to 25,000 protein-coding genes. In contrast, there may be up to 1 million different proteins in the human body. How can that be? This is possible because one gene can code for several different proteins. Therefore, the idea of inserting one gene and getting only one protein is very unlikely.
What does this mean? In theory, this means extra proteins of unknown function can arise from the process of genetic engineering in addition to the protein that was desired.(12) Even if one is certain of the safety of the engineered protein, one can’t be sure of the safety of various unknown proteins. This begs the question: are we looking for these extra proteins? Current comparative analysis between GMOs and conventional organisms is only completed regarding specific nutrients and chemicals (e.g., vitamin C, calcium, etc).(11) For example, the levels of vitamin C in conventional corn are compared to the levels of vitamin C in a GE variety and so on with other nutrients. If the GE variety of corn is found to be similar to conventional corn by these standards it is considered substantially equivalent.(11) By the idea of substantial equivalence, if a product is found comparable to its conventional counterpart, aside from the new gene and protein, then safety assessment should only focus on the new protein.(7) Therefore, the next step is to determine the safety of the engineered protein by assessing for risk of allergic or toxic reactions.(11)
But, does any of this answer the previously posed question? In short, no. This type of analysis does not look for rogue proteins. Certain types of analysis, such as proteomic or metabolomic analysis, can show the presence of these types of alterations. This type of analysis, however, is not currently very useful as it is difficult to interpret the findings due to the vast number of variables that can alter genetic expression – aside from genetic engineering – such as location, environmental conditions and year of cultivation.
One may like to assume that if the gene comes from a product that we already consume, it is unlikely that the gene will produce any proteins that would be harmful to humans. This is not an irrational assumption, though it is not necessarily an accurate one. Controls of gene expression occur largely outside the nucleus of a cell and are based on inherited properties of the organism (eg, in humans this could be environmental exposures of the parents, grandparents, etc) as well as the current environment of the organism. Therefore, assuming the expression of a gene will be the same from one organism to another, even if the gene is exactly the same, is not necessarily true. Additionally, because the gene insertion process is highly imprecise, a gene can very well be inserted into the middle of another gene leading to alterations in normal genetic expression.(2) Research has also shown that the gene insertion process can cause other kinds of mutations, such as rearrangement of genes at the insertion site, which could also lead to altered gene expression.(2)
A separate point of view asserts that because most proteins we consume are non-allergenic and completely safe, it is unlikely that a new protein is going to be problematic. After all, University of Nebraska-Lincoln’s AllergenOnline database reports that only 1,630 proteins (out of likely over a million possible proteins) are known to cause allergic reactions – less than 1%.(1) While this is true, it is somewhat misleading. True allergic reactions are known as a type I hypersensitivity response which involves the production of IgE antibodies to the offending substance. There are, however, other types of hypersensitivity responses and autoimmune reactions that can occur to proteins – some of which are still not well understood.
The typical industry funded feeding study on GMOs follows a very predictable and consistent format. A number of rats are fed a certain percentage of a GE product, while a number of control rats are fed a non-GE variety for a period of 90 days. At the end of the 90 day period, blood, urine and tissue samples are taken from the rats. They are then sacrificed and a number of outcomes are measured. The findings of these studies are routinely reported as insignificant with the safety of the GE product verified. Upon approval by the FDA the product is released for widespread use and consumption.
Let’s discuss one of these types of studies performed with glyphosate-tolerant corn – one of the most common GE products that is designed to be resistant to Monsanto’s popular Roundup herbicide. It is also known as Roundup ready corn. This type of corn has a gene inserted that is derived from the bacterium Agrobacteria sp.(6) The gene codes for a version of an enzyme normally found in plants, enolpyruvylshikimate-3-phosphate (EPSP). EPSP is involved in the production of certain amino acids that are necessary for the continued growth and health of the plant.(6) Roundup normally block the action of this enzyme leading to death of the plant.(6) The GE version of this enzyme, however, is resistant to the effects of glyphosate.(6)
The study used 6-week old male and female rats.(6) The rats were split into ten groups of twenty rats consisting of two control groups, two experimental groups and six reference control groups.(6) One control group was fed a diet consisting of 11% conventional corn grain diets, while the other control group was fed a diet of 33% conventional corn for a period of 13 weeks.(6) The experimental groups were fed the same percentage of glyphosate-tolerant corn.(6) Reference controls were all fed a diet of 33% conventional corn.(6) During the 13 week period, the rats were observed twice daily to make sure they were still living and once daily to assess for overt toxicity.(6) Blood was drawn at 4 weeks and at the end of the study.(6) Urine was also collected at this time.(6) At the end of the study, the rats were sacrificed and a number of organ and tissue samples were collected.(6) As previously mentioned, outcomes such as weight, blood counts, serum electrolytes, liver & kidney function, organ weights and tissue pathology were assessed.(6) There were no statistically significant findings to show that rats consuming glyphosate-tolerant corn were in any way adversely affected by it.(6)
There are a number of concerns that arise using this type of study to verify that a GE product is safe for human consumption. I’ll mention two that should be easily recognized. The first and most blatantly obvious concern is with the test subjects – they are not human. Rat and other animal studies are commonly used as preliminary research in the medical field, but cannot be relied upon when assessing for true health effects in humans. The same can, and should, be said for GE products. The second matter is the length of the study. 13 weeks, or approximately 90 days, may be useful for assessing short-term, overt toxicity, but it is not a sufficient amount of time to assess for long-term risk of adverse health effects. No matter what assumptions are made regarding substantial equivalence, the general safety of proteins or the usefulness of animal studies, the only truly valid way to assess the safety of a GE product in humans is by studying humans consuming a product for a valid length of time to assess for chronic health effects.
Roundup Herbicide
There is a reason to choose glyphosate-tolerant corn as a prime example of a GE product. In 2012, 93% of soybean crops, 80% of cotton crops and 73% of corn crops in the US were of this variety – Roundup ready.(5) But, just how safe is Roundup?
As previously mentioned, glyphosate works by inhibiting the enzyme EPSP found in plants. Yet, there is much debate over possible health consequences of glyphosate in humans. There is research supporting both sides of the topic leaving the issue ultimately undecided. Often, however, it is forgotten that herbicidal formulations, such as Roundup, contain more than just glyphosate. They contain a whole host of other chemicals that are designed to assist glyphosate in achieving its herbicidal goal. Unfortunately, many of these other chemicals don’t get the same attention regarding safety as glyphosate does.
One such chemical found in many roundup formulations is a polyethoxylated alkylamine known as POE-15.(9) In a recent study performed by Mesnage, Bernay and Seralini, it was found that POE-15 may be much more toxic to human cells than glyphosate or other chemicals found in Roundup formulations. The LC50 (lethal concentration at which 50% of cells are killed) of POE-15 was found to be only 2 ppm (parts per million) for hepatic and embryonic cells and only 1 ppm for placental cells.(9) According to this research, POE-15 is vastly more toxic to human cells than glyphosate, yet has not receive nearly the same amount of attention or safety testing.
What does this have to do with GMOs? The answer is simple. Since Roundup ready crops were first introduced the use of Roundup herbicide has increased dramatically. This means our environment, our food and our bodies are much more likely to be exposed to the various chemicals found in Roundup formulations, including POE-15. Unfortunately, the chronic health effects of exposure to all these chemicals are not currently well understood.
Beyond the scientific concerns, however, there are moral concerns. Monsanto, one of the largest agricultural biotechnology companies in the business of producing GE products lies at the heart of many of these concerns. The use of genetic engineering allows a company to patent a seed product, thereby controlling its use and prohibiting the common practice of seed collection from the previous year’s harvest. Patenting a seed or plant is in itself is questionable, yet what is even more alarming are the lawsuits that have been and are taking place over seed saving. In some of these lawsuits it has been found that seed dealers have forged farmers’ signatures on technology agreements and that many farmers were simply unaware that they were not allowed to continue the common practice of seed saving.(3) Prohibiting seed saving ties the farmer to Monsanto and requires them to continually purchase new seed each year which significantly increases a farmer’s expenses.
Confounding the situation is the matter of seed contamination which has become an ever increasing problem. Traditional seed stocks of corn, soy and canola have been found to be contaminated from 50-83% with GE content.(3) If a farmer uses contaminated seed stock and GE plants are found on his property, he or she may very well be held liable for patent infringement.
There is also much concern on the political side. As mentioned previously, before a GE crop can be released on the market it must also be approved by the FDA – a process that often goes exceedingly smoothly. Similar to the conflicts of interest found in GMO industry studies, conflicts of interest can also be found in the political realm. Over the years, a multitude of Monsanto employees or associates have become FDA employees. One of the most recent connections is Michael Taylor – the current FDA deputy commissioner for foods.(8) Taylor began his career in 1976 as a staff attorney at the FDA and then moved to King & Spaulding, where he represented Monsanto.(8) Taylor returned to the FDA in 1991 as deputy commissioner for policy and played a large part in preventing the labeling of milk from cows treated with bovine growth hormone (a Monsanto product).(8) In 1994, Taylor moved to the USDA and then back to Monsanto as vice president for public policy.(7) Taylor is well known to be in support of GE technology.(8)
Unfortunately, this is not a unique story. Margaret Miller moved from a Monsanto chemical lab supervisor to deputy director in the FDA.(10) Linda Fisher moved from Monsanto vice president of government and public affairs to deputy administrator of the EPA.(10) Lidia Watrud moved from manager of new technologies at Monsanto to positions in the USDA and EPA.(10) Roger Beachy moved from director of Monsanto’s Danforth Center to director of USDA’s National Institute of Food and Agriculture.(10) This is far from a comprehensive list. One can’t help but wonder exactly how much influence Monsanto has had and currently has over our government food regulatory agencies.
Aside from these moral and political concerns, all of the research that has been accomplished regarding genetic engineering has still not adequately proven the safety of GE foods. Though industry studies claim safety and many independent studies question such assertions, the truth is still unknown as the long-term human study is currently in progress on an unknowing population. Given our history of introducing novel chemicals such as DDT, asbestos and PBDE before the adverse health effects were determined, caution should be our guide. The benefits of GMOs do not outweigh the possible risks. Roundup ready crops are not solving world hunger or improving human nutrition, but rather are only making GMO companies more wealthy. We should learn from our past and let not greed control our motivations, lest we be prepared for it to destroy our health.
from curejoy

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