Pesticide Treadmill Jeopardizes Food Safety

Story at-a-glance

  • California environment officials have issued a notice of intent to put a Prop 65 cancer warning on Roundup
  • In 2013, in the midst of mounting questions about glyphosate’s safety, the Environmental Protection Agency doubled allowable limits of glyphosate in flax, soybean, and canola from 20 to 40 ppm
  • Researchers found Roundup causes necrosis and apoptosis in human cells starting at 50 ppm, which the researchers noted is “far below agricultural dilutions”


This is an older article that may not reflect Dr. Mercola’s current view on this topic. Use our search engine to find Dr. Mercola’s latest position on any health topic.

By Dr. Mercola

In late March of this year, glyphosate, the active ingredient in Monsanto's bestselling weed killer Roundup, was reclassified as a "probable carcinogen" by the International Agency for Research on Cancer (IARC), a division of the World Health Organization (WHO).

Glyphosate is most heavily applied on genetically engineered (GE) corn, soybeans, and sugar beets, but it's also commonly used to desiccate conventional (non-GMO but non-organic) wheat and protect other conventional crops from weeds.

California to Put Cancer Warning on Roundup

In response to the IARC's determination, British and German retailers have started removing Roundup from its lineup of weed killers sold to the general public. France has also announced plans to restrict its sale at garden centers.1

The IARC is one of the research agencies from which the California agency of environmental hazards gets its data to declare carcinogens under Prop 65 and, as predicted, environment officials have now issued a notice of intent to put a cancer warning on Roundup.2

Glyphosate cannot be washed off and can remain stable in foods for over a year.3 But what many don't appreciate is that Roundup is actually far more toxic because of its surfactants that synergistically increase glyphosate's toxicity.

GE crops are much more heavily contaminated with glyphosate than conventional crops by nature of their design, and this fact alone blows a massive hole in GMO safety claims.

Considering that, plus the fact that the US Department of Agriculture (USDA) does not test foods for glyphosate residues due to the high cost of doing so,4 a Prop 65 label would probably be appropriate for most non-organic processed foods as well — those with genetically engineered (GE) ingredients in particular.

Time will tell if California will ever take it that far, as that would truly be the death knell for Monsanto and other chemical technology companies, but it's definitely something to consider when you're buying your groceries.

Evidence Abounds Showing Glyphosate Is 'Definitely' Carcinogenic

While the IARC stopped short of a stronger cancer classification for glyphosate there's ample evidence showing it is quite "definitely" carcinogenic.5 Dr. Anthony Samsel even claims to have uncovered evidence showing Monsanto has known glyphosate promotes cancer since 1981. That's 34 years!

Feigning ignorance as usual, Monsanto has called for a retraction of the IARC's findings — a demand that is likely to be unmet, according to Aaron Blair, a scientist emeritus at the National Cancer Institute who chaired the IARC Working Group.

Blair has publicly defended the group's classification of glyphosate, saying it is "appropriately based on current science."

For a review of the published studies6 questioning the safety of glyphosate in terms of its effects on human and animal health, check out this compilation by Dr. Alex Vasquez, containing 220 pages worth of research.

Another illuminating and heavily referenced 80-page report7 worth reading through at your leisure is "Banishing Glyphosate", authored by Drs. Eva Sirinathsinghji and Mae-Wan Ho, with cooperation from six other researchers, including Dr. Don Huber and Dr. Nancy Swanson.

Recent follow-up research8,9 by Gilles-Éric Séralini — whose initial lifetime feeding study revealed massive tumor growth and early death — shows that long-term exposure to even ultra-low amounts of Roundup may cause tumors, along with liver and kidney damage in rats.

In this study, the dose used was "environmentally relevant in terms of human, domesticated animals and wildlife levels of exposure," prompting the authors to suggest Roundup may have significant health implications.

Did You Know? EPA Raised Allowable Glyphosate Limits in Food Two Years Ago

Some of the studies implicating glyphosate as a serious hazard to animals and humans go back several years, yet in July 2013, right in the midst of mounting questions about glyphosate's safety, the Environmental Protection Agency (EPA) raised the allowable limits of glyphosate10,11 in both food and feed crops.

Allowable levels in oilseed crops such as flax, soybean, and canola were doubled, from 20 ppm to 40 ppm — just 10 ppm below the level at which Roundup may cause cell death, according to research12 published in 2011.

Permissible glyphosate levels in many other foods were raised to 15 to 25 times previous levels. Root and tuber vegetables, with the exception of sugar, got one of the largest boosts, with allowable residue limits being raised from 0.2 ppm to 6.0 ppm. The level for sweet potatoes was raised to 3 ppm.

At the time, Beyond Pesticides criticized the EPA's decision, saying:

"Given that alternative methods of growing food and managing weeds are available, like those that exist in organic agriculture, it is unreasonable for EPA to increase human exposures to Roundup."

All such complaints and concerns fell on deaf ears, and Monsanto's well-oiled PR machine maintained glyphosate's extensive safety record. Fast forward a mere two years, and glyphosate will now carry a cancer warning label in California...

EPA Should Reassess Its Decision on Glyphosate Tolerance Levels...

It's important to remember that the allowable levels of glyphosate were recently significantly raised, because IF the US government does implement glyphosate testing for food, as indicated by the EPA back in April,13 then we'll probably still be assured that levels are "within safe limits," as we were back in December 2014 after the USDA tested a number of foods for glyphosate.14

But in light of glyphosate now being recognized as carcinogenic, it would seem prudent for the EPA to reassess its tolerance levels in food- especially when you consider that the vast majority of all processed foods are made with GE ingredients that are more heavily contaminated.

Just how much glyphosate is the average individual getting, if they're eating a primarily processed non-organic food diet every single day of the week?

Samsel and Seneff's groundbreaking research published in June 2013 — a mere month before the EPA raised allowable levels — suggests glyphosate may actually be the most important factor in the development of a wide variety of chronic diseases, specifically because your gut bacteria are a key component of glyphosate's mechanism of harm.

Another study15 published the following year investigated the effect of glyphosate on Americans' health, noting that glyphosate interferes with many metabolic processes in both plants and animals. The researchers also pointed out that previous studies show glyphosate "damages DNA and is a driver of mutations that lead to cancer."

Transgenic Bt Products Are Not Working Out Very Well Either

While Roundup Ready and other similar crops are designed to withstand heavy doses of herbicides, Bt plants are equipped with a gene from the soil bacteria Bacillus thuringiensis (Bt), which produces Bt toxin — a pesticide that breaks open the stomach of certain insects and kills them. Bt plants are engineered to produce this pesticide internally.  

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. There are three important points I want to make about such claims.

  1. 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,16 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.
  2. This isn't necessarily a new problem. According to the article, in 2002 farmers applied so much pesticide to fend off the whiteflies that soil and groundwater is thought to have been affected, and many now blame the exaggerated use of pesticides on the clustering of cancer cases being detected among those living in India's cotton belt.

  3. Secondly, research17 has shown that Bt crops, just like topical pesticides and herbicides, alters and destroys soil microbiology. According to the authors:
  4. "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."

The Biggest Bt Fraud of All

Third, but really most egregious of all, 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 pesticide18 (which helps explain why Bt plants damage the soil just like topical pesticides and herbicides do...)

This is a gross misrepresentation 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 fact, the reality is even worse than that. Topically applied Bt toxin biodegrades in sunlight and can also be washed off. The Bt toxin in these GE plants, on the other hand, does not degrade, nor can it in any way be removed or cleaned off the food because it's integrated into every cell of the plant. Moreover, the plant-produced version of the poison is thousands of times more concentrated than the topical spray, so in reality, Bt pesticide exposure has risen exponentially — no matter what the pesticide usage data says.

Adding insult to injury, Monsanto and the EPA swore that the Bt toxin produced inside the plant would still be completely safe as it would be destroyed in the human digestive system. Alas, this turned out to be false when, 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.19

Clearly, it is not destroyed inside your body; it bioaccumulates in your body, and research20 suggests it 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.

Another study21 published in 2011 found that Bt toxins affect human cells, both in isolation and in combination with glyphosate-based herbicides, including Roundup. 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."

Labeling GMOs Is Necessary to Protect Public Health

The food industry has spent $51.6 million on a series of efforts to defeat GMO labeling laws,22 including lobbing for HR 1599, which would bar states from implementing their own GMO labeling laws. As of July 21, Monsanto alone had spent $2.5 million lobbying Congress.23 In a similar vein, in 2013 and 2014, agribusinesses, agricultural organizations, and trade associations spent more than $11 million lobbying for an early version of S1500,24 which eliminates the need for permits to discharge pesticides into rivers, lakes, streams, and other bodies of water regulated under the Clean Water Act.

International trade agreements also threaten to restrict transparency about food — how it's produced, and where it comes from. Why are these industries spending so much money and going to such great lengths to eliminate transparency about toxic exposures and potentially harmful substances in our food supply? Could it be because they realize how bad the situation really is? And that if public knowledge grows by even just a little bit, they won't be able to continue running business as usual?  

Anyone who has taken the time to look at the available information will see that the situation is unsustainable and nearing a breaking point. The human body can only withstand so many toxic assaults before it falters, and we're already seeing young adults, and even children, exhibiting health problems you wouldn't ordinarily expect until well into adulthood. We need to turn this situation around. At present, the most urgent action item is to press our US Senators to reject HR 1599, so that efforts to label GE foods can move forward.

We Only Have a Limited Time to Set Our Senators Straight

Rep. Mike Pompeo (R-Kan) introduced a bill that would preempt states' rights to enact GMO labeling laws. It would specifically prohibit Congress or individual states from requiring mandatory labeling of GMO foods or ingredients. It would also allow food manufacturers to use the word "natural" on products that contain GMOs.

Unfortunately, the bill has been passed in the House and now heads to the Senate. There needs to be an extra push to put an end to the absurdity. It's imperative you contact your senators today urging them to not support HR 1599. Tell them this bill is an attack on consumer rights and states' rights, and you expect your elected officials to protect you.

You can find your senators' contact information by clicking the button below, or by calling the Capitol Switchboard at 202-224-3121. To set up an in-person meeting with your senators, contact their district office.

It's really imperative to concentrate our efforts on our senators right now, and to inform them accurately. They're being deceived by industry lobbyists, and this is our last chance to preserve our right to know what is in our food.

Contact Your Senators


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