By Dr. Mercola
Genetically engineered (GE) food comes from crops in which genes from one species have been integrated into another species — even between species in which this is biologically impossible in nature. The end result is a gene sequence that would never have occurred naturally.
There are two main types of GE crops:
- Herbicide-tolerant crops: Plants engineered to withstand heavy herbicide spraying without sustaining damage, such as Roundup Ready crops
- Pesticide-producing crops: So-called Bt plants are engineered to produce their own internal pesticide, so that when a bug takes a bite of the plant, it dies
Trying to control genetic changes via artificial modification is a dangerous game. An organism's genome is not static but fluid, and its biological functions are interconnected with its environment and vice versa.
Contrary to what the industry would like you to believe, the process of genetic engineering is imprecise at best, and is riddled with unintended and often unforeseeable consequences.
Of course that is about to change with the new technology, CRISPR-Cas9 that I reviewed last month. Once this technology is implemented, we will need to pay very careful attention to what the researchers are planning.
Genetic Engineering Is Riddled With Unintended Consequences
Viruses are typically used to genetically engineer the genes into a new species. These are known as viral transgenes, and there’s a profound lack of understanding of how this process actually works and what the ultimate ramifications are.
Compared to natural genetic modification (vertical gene transfer), artificial genetic modification is inherently hazardous because it lacks the precision of the natural process, enabling genes to be transferred between species that would never have been otherwise exchanged.
Artificial genetic modification uses horizontal gene transfer, which involves injecting a gene from one species into a completely different and naturally incompatible species, yielding unexpected and often unpredictable results — some of which may pose a hazard to animal and human health.
Approval Does Not Mean GE Crops Have a Proven Safety Record
In 1995, Novartis (which later became Syngenta) received approval to cultivate the GE maize known as Bt1761 in the U.S. It was the first Bt corn commercialized for animal feed. Due to controversies, it never gained much market success and the registration was allowed to lapse in 2001.2
In Europe, it was officially withdrawn from the market in 2007. Last month, Professor Gilles-Eric Séralini published a feeding study on this particular Bt corn, showing it was in fact toxic to cows over the long-term.
Prior to its introduction, Novartis had conducted just one feeding test on four cows for the duration of two weeks.3 One of the animals died one week into the test with electrolyte and mucosal problems. No scientific explanation could be found for the death, and the cow was removed from the protocol.
It’s really important to realize that animal feeding trials are not required to be done prior to the commercial release of a GMO, and if they are done, they’re typically extremely small, and very short in duration, like this one was.
Long-Term Studies Keep Finding Serious Health Problems With GMOs and Associated Chemicals
As an expert for the French government within the Biomolecular Engineering Commission, Séralini had access to the industry dossier on Bt176, and expressed strong objections to and concern over the lack of long-term feeding tests — the kind that have since become Séralini’s own hallmark specialty.
As you may recall, Séralini produced the first-ever lifetime feeding study on rats in 2012. The 2-year-long study evaluated lifelong effects of a Monsanto-produced GE corn that is prevalent in the U.S. food supply.
The rats developed massive breast tumors, kidney and liver damage, and early death. The major onslaught of diseases set in during the 13th month, which in human terms equate to about the age of 43, assuming that the average person lives to the age of 80.
Séralini has also investigated the health effects of glyphosate and Roundup.
In a study4,5 published last year, he found that long-term exposure to ultra-low amounts of Roundup — which is used on both GE and conventional crops in ample amounts — may cause tumors, along with liver and kidney damage in rats.
First GE Corn Shown to Be Toxic to Cows in the Long Term
In 1997, Gottfried Glöckner, an award-winning dairy farmer in Germany, became the first farmer to grow and feed Bt176 corn to his prized Holstein cows. The test continued until 2002.
According to Séralini, this was the longest running and most detailed observation of farm animals ever performed for a GE crop.
Since 1986, when Glöckner took over the farm, he’d had no cases of serious disease on his farm. That all changed once he started feeding his cows Bt176 in 1997. As noted on Séralini’s website:6
“When partial paralysis (paresis) accompanied by great fatigue, and problems in the kidneys and mucosal membranes arose in the animals, followed by death in 10 percent of cases, microbial causes were sought. All kinds of analyses were conducted ...
At this time, the dose of GMO Bt maize, which had been progressively introduced, had reached 40 percent of the diet. By 2002, the farmer had become convinced that Bt maize was the cause of the diseases. He sued Syngenta and had partial compensation for his losses7 ...
After all these court cases ended, Prof. Séralini gained access to veterinary records and to very complete archived data for each cow ... For the first time ever, an analysis of these data has been published8 ... New scientific data on Bt toxins and a thorough study of the records show that this GMO Bt maize is most probably toxic over the long term.
This study reveals once again the urgent need for specific labeling of the identity and quantity of GMOs, especially in food and feed. Long-term testing of GM food and the pesticides they are designed to contain must be carried out and made public. This is now more essential than ever.”
The Higher the GMO Content, the Greater the Health Risks
As Glöckner increased the amount of Bt176 corn in the cows’ feed, gradually going from 2 to 40 percent over the course of two years, the worse his cows fared. At the outset, 70 percent of his cows produced high yields of milk, which is considered normal.
Once the GMO content of the feed reached 40 percent, a mere 40 percent of his cows were high-yielding. In 2000, milk tested positive for the Bt176 DNA specific fragment, which under European law meant the milk had to be labeled as coming from GE-fed animals.
Peak mortality was reached in 2002, when 10 percent of his cows died after suffering a long period of partial paralysis. Thirty percent of the herd was sick with a variety of ailments.
A number of cows were diagnosed with liver disease, mucosa problems, irregular heart function, mammary gland breaks (which is exactly as disturbing as it sounds: the study includes pictures), and general “abnormal behavior” suggesting chronic lack of energy.
As the GMO ratio peaked, fertility also began to drop significantly. Some of the animals tested positive for Chlamydia, but had no visible infection. Overall, kidney function appeared to be the most affected.
Because the farmer introduced new cows to his herd here and there to replace those who had died or were too sick to be milked, the toxic effects may actually be underestimated, as the replacement animals had not previously eaten the GMO feed, and were therefore exposed to it for a much shorter duration.
Indeed, Séralini points out that toxic effects such as these would likely be missed under common conditions on factory farms with high and rapid animal turnover for that very reason. Especially when the feed is not specifically labeled, identifying the type of GMO and precise amount.
Pesticide-Producing Plants May Also Harm Human Health
Like other Bt crops, Bt176 was genetically engineered to produce Bacillus thuringiensis(Bt toxin) — a pesticide that breaks open the stomach of certain insects and kills them. Bt plants are engineered to produce this pesticide internally, so it’s present in every cell of the plant, from root to tip, and cannot be washed off.
Previous in vitro experiments9,10 have shown that the Bt toxin these plants produce affects human cells, both alone and in combination with glyphosate-based herbicide residues.
Pesticidal crystal proteins Cry1Ab and Cry1Ac, two subspecies of the Bt toxin, were tested on cells from the embryonic kidney cell line 293, looking at specific biomarkers indicating cell death. Concentrations ranged from 10 parts per billion (ppb) up to 100 parts per million (ppm).
Cry1Ab caused cell death starting at 100 ppm. Roundup alone was found to cause necrosis (cell death resulting from acute injury) and apoptosis (cellular “suicide” or self-destruction) starting at 50 ppm, which the researchers noted is “far below agricultural dilutions.”
According to the authors: “In these results, we argue that modified Bt toxins are not inert on nontarget human cells, and that they can present combined side effects with other residues of pesticides specific to GM plants.”
Monsanto and the U.S. Environmental Protection Agency (EPA) claimed the Bt toxin produced inside the plant would be completely safe for human consumption because it would be destroyed in the human digestive system. This has been proven false more than once.
Research11 published in 2007 found that antibiotic resistance marker genes from Bt176 maize were able to survive for longer periods in gastric juices taken from patients on anti-acid drug treatment, thereby potentially increasing the risk of antibiotic resistance. According to the authors:
“Our data indicate the possibility that in particular cases the survival time could be so delayed that, as a consequence, some traits of DNA could reach the intestine. In general, this aspect must be considered for vulnerable consumers (people suffering from gastrointestinal diseases related to altered digestive functionality, physiological problems or drug side-effects) in the risk analysis usually referred to healthy subjects.”
Then, in 2011, doctors at Sherbrooke University Hospital in Quebec found Bt-toxin in the blood of 93 percent of pregnant women tested, 80 percent of umbilical blood in their babies, and 67 percent of non-pregnant women.12 It’s quite clear that Bt toxin is not destroyed when passing through your digestive system, and that it can bioaccumulate in your body.
According to one study,13 Bt toxin may produce a wide variety of immune responses, including elevated IgE and IgG antibodies, typically associated with allergies and infections, and an increase in cytokines, associated with allergic and inflammatory responses — conditions that have markedly risen in prevalence since the advent of Bt crops.
Transgenic Bt Crops Promote Resistant Pests and Destroys Soil Biology
One of the selling points and touted benefits of GE crops like Bt cotton and Bt corn is reduced pesticide usage, as the plant itself will kill any bug that chews on it. As with so many other GMO claims, this one cannot stand up to scrutiny. For starters, just like exaggerated herbicide use has led to the rapid development of resistant superweeds, so have Bt plants led to the emergence of resistant pests.
According to The Times of India,14 farmers in Punjab and Haryana are seeing significant losses of their Bt cotton crops to the whitefly. To address the problem, increasing amounts of pesticides have been applied. During an outbreak in 2002 farmers applied so much pesticide to fend off the whiteflies that soil and groundwater are thought to have been affected.
Many now blame the exaggerated use of pesticides on the clustering of cancer cases being detected among those living in India’s cotton belt. Research15 has also shown that Bt crops, just like topical pesticides and herbicides, alter and destroys soil microbiology. According to the authors:
“Our data showed that the cultivation of Bt maize significantly increased the saturated to unsaturated lipid ratios in soils which appeared to negatively affect microbial activity.”
Beware: Bt Toxin Produced by Bt Plants Is Not Counted Toward Total Pesticide Exposure
Last but not least, it’s well worth noting that the Bt toxin produced in these Bt crops are NOT included as part of the total human pesticide exposure. This despite the fact that Bt plants are actually registered with the EPA as a pesticide.16 This also helps explain why Bt plants damage the soil just like topical pesticides do.
Ignoring Bt toxin produced by Bt plants, as if it never were to reach a dinner plate, is a gross misrepresentation of facts and outright fraudulent propaganda. How can they claim reductions in pesticide exposure as a result of Bt plants when every single cell of the plant contains it?
And how can they not include the plants in the pesticide usage data when the plant itself is registered as a pesticide? The failure to count the toxin inside the plant, and only counting the pesticides applied topically, is a significant loophole that makes Bt plants appear to provide a benefit that in reality simply isn’t true.
In reality, Bt exposure has likely increased exponentially with the introduction of Bt plants. Why? Because the plant-produced version of the poison is thousands of times more concentrated than the topical spray, and while topically applied Bt toxin biodegrades in sunlight and can be washed off, the Bt toxin in these GE plants does not degrade, nor can it be removed or cleaned off the food since it’s integrated into every cell of the plant.
Besides that, Bt toxin in GE soy, cotton, and corn has also been exempted from residue tolerance levels by the EPA, so absolutely no one is looking for or paying any attention to the amount of Bt toxin you’re exposed to via the food you eat!
How to Avoid Bt Crops
So, if you want to avoid eating Bt plants, which foods end up on the “buy certified organic” list? The following list shows which Bt crops have received approval for commercialization in which countries as of 2013.17,18 (A Bt poplar tree has also been approved for planting in China.)
Cotton is of course not a food, but is used for cotton clothing. The genetic engineering of cotton is one reason why I recommend buying clothing made with organic cotton.
| Cotton || Argentina, Australia, Brazil, Burkina Faso, Canada, China, Colombia, Costa Rica, European Union (EU), India, Japan, Mexico, Myanmar, New Zealand, Pakistan, Paraguay, Philippines, Singapore, South Africa, South Korea, and United States of America (USA)
| Eggplant || Bangladesh
| Maize/Corn || Argentina, Australia, Brazil, Canada, Chile, China, Colombia, Egypt, El Salvador, EU, Honduras, Indonesia, Japan, Malaysia, Mexico, New Zealand, Panama, Paraguay, Philippines, Russian Federation, Singapore, South Africa, South Korea, Switzerland, Taiwan, Thailand, Turkey, USA, and Uruguay
| Potato (“Atlantic NewLeaf potato”19,20) || Australia, Canada, Japan, Mexico, New Zealand, Philippines, Russian Federation, South Korea, and USA
| Rice || China and Iran
| Soybean || Argentina, Australia, Brazil,21 Canada, China, Colombia, EU, Japan, Mexico, New Zealand, Paraguay, South Korea, Taiwan, Thailand, USA, Uruguay
| Tomato22,23,24 || Canada, Chile, and USA