Research Reveals Monsanto Has Known Since 1981 That Glyphosate (RoundUp) Promotes Cancer

Monsanto Glyphosate

By Dr. Joseph Mercola

Contributing writer for Wake Up World

Glyphosate, the active ingredient in Monsanto’s best-selling herbicide Roundup, is one of the most commonly used herbicides in the world. An estimated one billion pounds a year is sprayed on our food crops,1,2 resulting in the average American eating several hundred pounds of glyphosate-contaminated food every year.

How might that affect your health? Dr. Anthony Samsel is an expert in this area, and he reveals a number of glyphosate’s adverse effects. Armed with this understanding, you’ll likely be far more motivated to eliminate this pernicious toxin from your diet — and to take action to get it out of our food supply so that everyone can be protected.

Dr. Samsel is a research scientist who is passionate about farming, gardening, and agriculture, making him particularly suitable for investigating glyphosate.

“I was with the ‘think tank,’ Arthur D. Little (ADL) in Cambridge, Massachusetts for many years working as a research scientist on many types of projects, from product development to environmental sciences to later switching to health sciences,” he says.

He’s also done contract work for the Environmental Protection Agency (EPA), and as a hazardous materials expert, he’s worked for the United States Army Corps of Engineers (USACE), the United States Navy (USN), and the United States Coast Guard (USCG). For example, Dr. Samsel was one of the authors of the Chemical Hazard Response Information System (CHRIS) manual for the US Coast Guard. He is also a valuable contributor to our article comments section (Vital Votes).

Besides his career in science, he also owned and operated several farms in New England, and it was this first-hand experience that led him to begin investigating the effects of glyphosate in the first place.

“I started using glyphosate myself commercially around the farm and my properties back in the late ’70s or early ’80s, when it first came on the market,” he says.

“I believed the hype like all the other farmers and people around the world do, that glyphosate is as safe as salt and that it broke down into harmless chemicals that did no harm. I believed all that stuff until I started studying the chemical.

Being a research scientist, a chemist, I knew what to look for. Having worked in public health, I was familiar with how chemicals had effects on the human body and on animals. So I started approaching it from that aspect.

As far as my own health, it started to suffer. That’s what put me on the road to take a look at this chemical because I was using it.”

Human Urine is Turning Into Herbicide…

One interesting experience that got him thinking was when he tried to deter deer from eating his crops. He’d run out of coyote urine, which is an effective deterrent, so he used his own urine. Curiously, he noticed the weeds where he’d sprayed his urine were dying, despite the fact he’d not sprayed any Roundup there. He then realized his own urine was acting like an herbicide!

“I did some controlled experiments in the greenhouse with some plants and the same thing happened. Those plants died. Then, I started looking at my diet,” he says.

“The only organic food I was eating was out of my own garden and the stuff that I would can and preserve. But for everything else, I’d go to the supermarket and I ate boxed food and what-not. I started to put two and two together; that maybe this was the reason why I wasn’t feeling good.

Then I started looking into glyphosate because I was using it. That was my primary chemical exposure other than my food.

Then I realized they were using [glyphosate] on genetically engineered crops, and I started looking at the US Department of Agriculture (USDA) to see what food would have glyphosate or glufosinate in them.

[Glufosinate] is similar to glyphosate and used in genetically engineered crops. It’s not as widely used as glyphosate, but that’s still a problem to public health. All herbicides are ‘a’ problem to public health. There should be no herbicides in our food supply. None.”

90 Percent of Soybeans Found to Contain Glyphosate Residues

Unfortunately, testing for glyphosate and glufosinate is expensive and is the excuse the USDA uses for not  testing for it, and no contamination data was available for Dr. Samsel to review. Eventually, he convinced the USDA to release the results of a series of tests in 2011. In all, they tested 400 samples of soybeans, and they found more than 90 percent of the soybeans had glyphosate residues in them.

However, when the agency sent him a pre-publication copy of the report, he noticed they were only reporting on 300 out of the 400 samples.

“I started looking at the data. I noticed that the amount of aminomethylphosphonic acid (AMPA), which is the metabolite of glyphosate, was greater than that of the glyphosate itself.

If you analyze the glyphosate, you’re going to get glyphosate if the residue is in the crop, but you’re also going to get the metabolite AMPA. But looking at the numbers, they just didn’t make sense. I believed they’ve cherry-picked the data so that the data didn’t exceed the EPA residue limits,” he says.

Unfortunately, when he tried to get an explanation for the discrepancy in the data, his USDA contact was no longer working there, and he hasn’t been able to find him since.

Advocacy Group Now Offers Testing for Glyphosate in US

While the USDA does not test food for glyphosate residues, this may soon change. The US Environmental Protection Agency (EPA) recently announced US regulators may start testing for glyphosate residues in the near future 3,4,due to rising consumer concerns about the health impact of this chemical.

Meanwhile, the Organic Consumers Association (OCA) has joined forces with the Feed the World Project, launching the world’s first glyphosate testing for the general public.6,7,8,As reported by the OCA:

“The project, with specific focus on women and children in the US, is offering the first-ever validated public LC/MS/MS glyphosate testing for urine, water and soon breast milk… The testing OCA, Feed the World and many other organizations will begin offering [on April 22] will allow everyone who wants to know whether or not, and to what extent, they personally have been exposed to glyphosate.

We expect that once the public learns how widespread the exposure has been—in the context of the recent report from the World Health Organization that glyphosate is a probable human carcinogen—public pressure will eventually force governments worldwide to finally ban Roundup.”

The Importance of Bacteria for Optimal Health

Dr. Samsel understood that his gut problems were related to bacteria and that just as healthy soil needs beneficial microbes, so does your gut. This was something instilled in him by his grandfather, who taught him that healthy bacteria in the soil help grow healthy crops. Not surprisingly, when he cleaned up his diet, his gut dysbiosis cleared up, as did a number of neurological problems he’d started experiencing.

At that point, he began delving deeper into the science of the human microbiome. Many are unaware of the fact that glyphosate is patented as an antibiotic. It’s designed to kill bacteria, which is one of the primary ways it harms both soils and human health. Recent research has even concluded that Roundup (and other pesticides) promotes antibiotic resistance. Dr. Samsel was actually the person who dug up the patents showing glyphosate is a biocide and an antibiotic.

“Some of the pathogens, like Salmonella and Pseudomonas, are resistant to glyphosate. When we ingest residues of glyphosate, glyphosate in the acidic environment dissociates. The acid glyphosate then is able to do a number on the bacteria, the same as it does in plants. It kills plants and bacteria in our plants.

Our gut has a beautiful ‘lawn’ of upwards of a thousand various species. Each species of bacteria has a specific function. We might liken the bacteria of our microbiome to mining and manufacturing companies. You might visualize the bacteria with mining helmets and pick axes. They mine the minerals in your biology that your body needs as co-factors for various biochemical processes. Your bacteria also manufacture vitamins and other biomolecules that are essential.

Even some of your fatty acids, which serve as signaling molecules, are manufactured by your bacteria. Our bacteria manufacture most of our B vitamins – B6, B9, and B12, which is cobalamin – essential to our neurology. Bacteria also manufacture vitamin K and some of your vitamin C. We have a symbiotic relationship with these bacteria. We help them and they help us. They take the food and they don’t just break it down and obliterate it to unrecognizable things. They dismantle the food, and they utilize everything that’s in the food.”

Bacteria Also Produce Essential Amino Acids and More

Bacteria are also responsible for producing essential amino acids such as tryptophan, phenylalanine, and tyrosine. So in addition to chelating out various vitamins and other important elements, glyphosate also disrupts bacteria manufacturing aromatic amino acids. It also disrupts methionine, a sulfur amino acid crucial for detoxification, and glutamate. All of this can have a profound influence on your biology. For example, as Dr. Samsel explains:

“Glyphosate disrupts the aromatic amino acid tryptophan, and tryptophan is necessary for the production of serotonin. Of course, from serotonin, we make melatonin and from melatonin, we make melanin. There are several biomolecules that are very important to your health and biology. Serotonin regulates and controls blood sugar. It also regulates IGF-1, which is insulin-like growth factor. IGF-1 is necessary for neurogenesis, for your ability to produce new neurons throughout life, and also for regulation of your physiology. Serotonin also activates the enzyme endothelial-derived nitric oxide synthases (eNOS), which is responsible for insulin secretion.”

Serotonin also catalyzes nitric oxide (NO) production in the vasculature providing airway tone and smooth muscle relaxation, and 90 percent of your serotonin—which is known as a neurotransmitter—is actually produced in your gut by certain bacteria,not in your brain.

Today, millions of prescriptions are being written for selective serotonin reuptake inhibitors (SSRIs), which are designed to increase serotonin in your brain. Yet 90 percent of it is manufactured in our gut! Dr. Samsel gave another excellent interview with Zen Honeycutt10 in 2013, in which he describes the impact glyphosate has on your gut bacteria, so for more information, please listen to the following helpful interview as well.

Monsanto Has Known for Over 35 Years that GMOs Promote Cancer

Dr. Samsel eventually asked the EPA for Monsanto’s trade secret documentation, as most of the approval process for glyphosate was based on studies Monsanto had done by outside contractors. That process began in the late 1970s and concluded around 1983 with the registration of the chemical. Since then, it’s gone through a couple of re-reviews. But Dr. Samsel wanted access to those documents to investigate what the EPA and Monsanto really knew about glyphosate from the very beginning.

“I asked EPA, as a research scientist, to be able to access those documents in my research. I was denied by the Environmental Protection Agency, initially,” he says. “It finally took Senator Shaheen’s office, here in New Hampshire, to move the EPA… They sent [the documents] to me on a disc. I had to sign for them. I was also told that I could not share them with foreign nationals under a penalty of law…

However, I’ve been going through 12 to 14 of these documents in the file. They represent thousands and thousands of pages of data on studies that were done on laboratory animals. What amazed me was that Monsanto knew in 1981 that glyphosate caused adenomas and carcinomas in the rats that they’ve studied...The highest incidence of tumorigenic growth occurred in the pituitary gland… the second highest levels were in the breasts of the female rats, in the mammary glands… Thirdly, the next highest tumorigenic growth was found in the testicles of male rats.”

In essence, Monsanto’s research of glyphosate showed similar findings as Dr. Gilles-Éric Séralini, whose damning lifetime GMO feeding study11 was wrongfully retracted12,13,14,15largely due to Monsanto’s influence. (Séralini’s paper was later re-published with open access in the Springer Group journal Environmental Sciences Europe.16)

Monsanto’s own research also supports the WHO’s International Agency for Research on Cancer (IARC) determination that glyphosate is a Class 2 A “probable human carcinogen.”17,18,19 –a determination Monsanto is now trying to get retracted. What’s more, the research shows that lower doses of glyphosate tend to have a greater effect than higher doses, and the doses at which damage was found to occur are comparable to the glyphosate levels found in wheat, sugar, corn and soy in the American diet.

Monsanto Never Published These Negative Findings

So how did Monsanto and Biodynamics—the company doing the research—hide these inconvenient facts? According to Dr. Samsel, they cancelled out the controls and the damning findings by using historical control data from unrelated studies. It’s also worth noting that these negative findings were never published in the peer-reviewed literature or submitted to the EPA or the Food and Drug Administration (FDA). Cancer was clearly shown in their 26-month long feeding study, but the only studies Monsanto has published are studies done in less than three months, which hides the consequences of eating glyphosate and genetically engineered foods over the course of a lifetime.

“I’m looking at a Biodynamics report here as Project number 77-2062, ‘A Lifetime Feeding Study of Glyphosate in Rats,’ and every page of this document says, ‘Contains trade secret or otherwise confidential information of Monsanto Company.’ I have a letter here from Monsanto’s health and safety officer. He was the head guy at Monsanto at the time, back in 1981. In his letter, he asked the US EPA to seal the documents and to treat them as trade secret. I personally feel that this is a violation of the public review process…

Now that I’ve looked at Monsanto’s trade secret documents that the public doesn’t have access to, I’m in the process of writing the Environmental Protection Agency and I’m asking them to release those. They have no right to withhold that information from the public. Because what I’ve seen in those documents, it clearly shows that Monsanto knew in 1981 that glyphosate caused tumorigenic growth and carcinomas in multiple organs and tissues... At the rate we’re going, we’re going to kill billions of people,” Dr. Samsel says.

Removing Glyphosate is Imperative to Protect Human Health and Future Generations

According to Dr. Samsel, we’re seeing the effects of glyphosate in human disease statistics now. His work with Dr. Stephanie Seneff and Dr. Nancy Swanson show that chronic disease rates are at an all-time high, including the specific tumors found in Monsanto’s 26-month feeding study, as well as the Séralini study and others—specifically pituitary, kidney, breast, testicular, thyroid tumors, and thymic hyperplasia.

“There was some work that was recently done where they looked at the CT scans of patients who had thyroid disease and also found that they had thymic hyperplasia. Well, guess what? In the rat study, they found high incidence of thymic hyperplasia as well as thyroid adenomas and carcinomas,” Dr. Samsel says. “If we don’t take this chemical out of the food supply, everybody will be affected. Everybody that is eating the Western diet. Everybody.”

Now, for some diseases, the incidence rate among rats were slightly less than 50 percent—some were as high as 80 percent of the treated group. Obviously, we’re not seeing 80 percent of people in Western populations coming down with tumors. But we might eventually… Rats have an average lifespan of two to two and a half years, whereas the human lifespan is around 80. We’ve only been eating GMOs for about 15 years, but already disease statistics are clearly rising, and rising dramatically. Dr. Samsel believes there’s no doubt genetically engineered (GE) foods will shorten the human lifespan.

“In the 20th month, the rats had an 80 to 90 percent survival rate. But when we got to around 24 months, more than 50 percent of the rats had died. When we got to month 26, I think they only had 30 percent left.”

While correlation is not causation, were we to extrapolate, it would suggest that unless we stop eating glyphosate and genetically engineered foods, the vast majority of us will contract a life-threatening disease in our late senior years, and few will die from plain old age. Other non-life threatening diseases are also cropping up at a furious rate—neurological disorders such as autism, attention deficit hyperactivity disorder (ADHD), and a wide variety of behavioral problems.

When I began practicing medicine in the early ’80s, the autism rate was one in 10,000. Now it’s as low as one in 30, according to some estimates. According to Drs. Samsel and Seneff’s estimations, in the next decade, half of all people born will have some form of autism! “That’s correct, if we continue on the same trajectory, it will be one in two, which is frightening,” Dr. Samsel says.

Studies May Be Using Contaminated Controls…

On a side note, it’s important to realize that when studies are done, they do not test the control diet for the presence of glyphosate, which may dramatically skew results and effectively hide harmful effects. According to Dr. Samsel:

“They are continuing to do that. As I look deeper into the studies, they didn’t analyze the water. They did not analyze the feed for other contaminants. I contacted Purina and asked them for a comment about their animal chows and their laboratory feed. They do analyze for some of the basic pesticides and fungicides, like malathion, some of the other organophosphates, and some of the fungicides.

But they don’t analyze for glyphosate in those feeds. Going back to when they did these studies back in 1978 and 1980, they didn’t analyze the feed, but the most popular pesticides used at the time in growing corn and soy for those animal feeds, were the organophosphates. Some of the organophosphates were carbaryl and lannate.

What’s interesting is that I also turfed up many synergy patents. I’ve read all of Monsanto’s patents, plus patents from other companies that have also done work with glyphosate. Glyphosate is a synergist with other antibiotics, with fungicides, and with most of the chemicals that I’ve seen it used in combination.

I even wrote about it being synergistic with imidacloprid, the systemic pesticide that’s been implicated in harming the bees. The effects they saw in the Biodynamics studies in the controls, they were feeding contaminated feed to these animals…which are known to induce some of the tumorigenic growths. But the fact that the glyphosate-dosed animals had higher incidences…shows that there was a synergy with whatever was in that feed.”

Clearly, this is something the EPA and FDA must address. When laboratory tests with animals are done, they really need to look at the residue levels of glyphosate and other chemicals in the animal chow because it’s skewing all the laboratory results, and making the risks appear non-existent.

The Problem with Genetically Engineered Plants

According to Dr. Samsel, glyphosate is only one-half of a two-part problem. The other half is the genetically engineered plants. For the past two years, he’s been conducting field experiments and laboratory analysis of 33 varieties of genetically engineered corn. This year, he’s branching into soy. Not only are there Roundup-resistant GE crops, there are also Bt crops, which produce their own internal pesticide called Bacillus thuringiensis (Bt). But there are also glyphosate and glufosinate toxins involved, because in many GM crops, the genes are stacked.

“I’m looking at the untreated [genetically engineered corn], and then I’m spraying it with the herbicide [glyphosate]. I’m analyzing the fatty acids and the mineral content. I’m also looking at the isomers of the vitamins. What I’m finding is that there’s a difference between those treated with the herbicide and those that are not treated. The herbicide influences the mineral content of even the genetically engineered resistant varieties, making them particularly more deficient in manganese, cobalt, and copper, but particularly manganese. I’m also finding that the fatty acids are being skewed slightly but also the vitamins, particularly the isomers of vitamin E, tocopherol.”

He’s found that GE varieties of soy, canola, and corn oil contain mostly gamma-tocopherol opposed to alpha-tocopherol (types of vitamin E). Alpha-tocopherol is really beneficial to our biology whereas gamma-tocopherol induces inflammation, particularly in your lungs. Hence Dr. Samsel believes these GE oils may influence rates of asthma and Chronic Obstructive Pulmonary Disease (COPD). On the whole, it seems clear that hundreds of millions of people could improve their health simply by avoiding glyphosate and genetically engineered foods.

The Good News: You Can Get Glyphosate Out of Your System Fairly Quickly

One important question many are likely to have is, once you decide to avoid glyphosate-contaminated foods, how do you detoxify? Here, there’s good news because glyphosate is fairly quickly eliminated via urine and feces—provided you’re not continuously putting more in. And if you need any more reasons to stop eating glyphosate contaminated food, consider this: one secret study Dr. Samsel reviewed found that glyphosate quickly went into the bone marrow, which is where the formation of blood cells takes place. The glyphosate remained stable in the bone marrow for at least 10 hours.

The white blood cells produced during that time go to the thymus and tonsils, where they mature. So glyphosate really works on the molecular level, affecting not only your bacteria, but also your blood cells. Importantly, glyphosate also both up and down regulates genes. For example, in E.coli bacteria, glyphosate up and down regulates about 1,040 genes, many of which are involved with cytochrome P450 enzymes, as well as glutathione S transferase, which is another first line of defense your cells employ to detoxify.

How to Reduce Your Family’s Exposure to Pesticides

Your toxic load is closely linked to your diet, as so many of the chemicals you’re exposed to on a daily basis are contaminants in foods and/or its packaging. Non-organic processed foods will expose you to the greatest amounts of chemicals and potential toxins, including pesticides and genetically engineered organisms (GMOs), but virtually all non-GMO whole foods will tend to be contaminated with pesticides to some degree as well. To reduce your family’s exposure to glyphosate and other toxic chemicals, please consider the following advice:

  1. Buy organic fruits and vegetables. Non-organic fruits and vegetables most likely to be grown using pesticides include apples, peaches, celery, and potatoes. For a full list of the most and least contaminated produce, please see the Environmental Working Group’s shopper’s Guide to Pesticides.20
  2. Add fermented foods to your diet. The lactic acid bacteria formed during the fermentation of kimchi may help your body break down pesticides, so including fermented foods can be a wise strategy to help your body’s natural detoxification processes. Also make sure you’re getting enough fiber in your diet, as it too plays an important role in detoxification.
  3. Choose seafood wisely. Opt for low-mercury fish varieties, such as wild caught Alaskan salmon, anchovies, and sardines, and avoid farm-raised fish, which are often heavily contaminated with PCBs and mercury. To optimize youromega-3, you may also consider taking a krill oil supplement.
  4. Filter your tap water.Municipal water supplies can be contaminated with any number of potential toxins, so filtering your water is always a wise idea. Be particularly mindful of avoiding fluoridated water when preparing infant formula.
  5. Replace your non-stick pots and pans with ceramic or glass cookware.
  6. Avoid plastic food containers, bottles, and mugs.Instead, opt for glass, ceramic, or stainless steel varieties.
  7. Avoid using dangerous chemicals on your lawn. If you have a lawn care service, make sure they’re not using organophosphate pesticides.
  8. Check your school’s/employer’s pest control policy. If they have not already done so, encourage your school district/employer to move to Integrated Pest Management, which uses less toxic alternatives.
  9. Switch to organic personal care products,and avoid using artificial air fresheners, dryer sheets, fabric softeners, or other synthetic fragrances. Any product containing “fragrance” will typically contain high levels of endocrine-disrupting phthalates.

Dr. Mercola Interviews Dr. Samsel on the Dangers of Glyphosate

Article sources:

Recommended articles by Dr. Mercola

About the author:

Dr. Joseph MercolaBorn and raised in the inner city of Chicago, IL, Dr. Joseph Mercola is an osteopathic physician trained in both traditional and natural medicine. Board-certified in family medicine, Dr. Mercola served as the chairman of the family medicine department at St. Alexius Medical Center for five years, and in 2012 was granted fellowship status by the American College of Nutrition (ACN).

While in practice in the late 80s, Dr. Mercola realized the drugs he was prescribing to chronically ill patients were not working. By the early 90s, he began exploring the world of natural medicine, and soon changed the way he practiced medicine.

In 1997 Dr. Mercola founded www.Mercola.com, which is now routinely among the top 10 health sites on the internet. His passion is to transform the traditional medical paradigm in the United States. “The existing medical establishment is responsible for killing and permanently injuring millions of Americans… You want practical health solutions without the hype, and that’s what I offer.”

Visit www.Mercola.com for more information, or read Dr. Mercola’s full bio and resume here.


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