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Is Glyphosate Weed Killer in Foods and Supplements Toxic?

How concerned should I be about glyphosate in foods and supplements?

Products that contain more than 1,100 micrograms (mcg) of the herbicide glyphosate per daily serving will, starting July 2018, be required to have a label warning if sold in California, which has applied a fairly strict limit based on current science. However it seems unlikely that any food products exceed this limit, as explained below. The label will warn the product contains a chemical known to cause cancer and birth defects or other reproductive harm. This level of exposure is estimated to pose a 1 in 100,000 lifetime risk of cancer, as determined by the International Agency for Research on Cancer part of the World Health Organization. However, as discussed below, it seems unlikely that any food product will exceed this limit.  

In contrast, the European Food Safety Authority concluded that glyphosate is unlikely to pose a carcinogenic hazard (and that it does not have endocrine disrupting properties) but set a maximum acceptable daily intake limit based on reproductive toxicity shown in animal studies. The limit in Europe is currently set at 0.5 milligrams (or 500 mcg) of glyphosate daily per kilogram of body weight, which works out to about 34 milligrams, or 34,000 mcg, for a 150 lb person. The U.S. daily limit, set by the Environmental Protection Agency, is 3.5 times as high Europe's, although some have called for lower limit. 

Glyphosate is the synthetic chemical in RoundUp herbicide, designed to kill weeds around plants that have been genetically altered to withstand it, such as genetically modified (GMO) soybeans and corn. It is also sprayed on many types of conventional crops such as wheat, oats, and barley prior to harvest as a drying agent and to even-out maturity. A USDA study in 2012 found that it was also commonly used on cherries, avocados, apples, lemons, grapefruit, peanuts, pecans, and walnuts ( Glyphosate is also found in processed foods containing these ingredients cannot be removed by washing, cooking, or baking. It can remain stable in food for a year or more.

Independent testing commissioned by the advocacy organization Food Democracy Now! and reported in November 2016 showed the concentrations of glyphosate in popular foods. The highest level was 1,125.3 ppb (or 1.1253 mcg per gram) in Original Cheerios. Based on this, a suggested serving of 28 grams of Original Cheerios would contain 32 mcg of glyphosate. This is much lower than California's 1,100 mcg warning level limit and far from the European daily intake limit of about 34,000 mcg for a 150 lb adult. Other breakfast cereals, such as Corn Flakes, Raisin Bran, Special K, and Wheaties contained less than one-tenth the amount in Original Cheerios. Although one might expect organic foods to be devoid of glyphosate, Food Democracy Now! actually found a higher concentration (119 ppb) of glyphosate in 365 Organic Golden Round Crackers than in most cereals, and even Kashi Organic Promise cereal contained glyphosate at 25 ppb, possibly due to cross-contamination of ingredients. The report notes that "...even organic farmers are having their crops/ our food contaminated."

The relatively high concentration of glyphosate in Original Cheerios is due to its main ingredient: whole grain oats. Independent testing shown in a 2016 presentation by and FDA scientist (see slide 30) found a similar level of glyphosate in other oat cereals, such as instant oatmeal packets, steel-cut oats, and infant oat cereal, although there was no detectable glyphosate in the organic oats it tested from Bob's Red Mill, 365 Whole Foods, Sprout, or Nature's Path.

It's possible that dietary supplements containing grains, soy, fruits, and whole food supplements could contain glyphosate, as could supplements with other ingredients that are cross- contaminated with glyphosate from other sources. Again, however, it would be highly unlikely that the amount of glyphosate would exceed established safe limits, particularly as serving sizes for supplements are typically smaller than that of foods.

The bottom line: Glyphosate safe or unsafe?

Glyphosate is known to cause reproductive toxicity bases on animal models, and it may possibly be a carcinogen -- although there is dispute about this. Due to its widespread use as an herbicide, it is found in many foods. However, at standard serving sizes (and even several times those sizes) even foods with the highest known concentrations of glyphosate, such as conventionally grown oats, appear to contain amounts of glyphosate far below those that pose a safety risk or require any type of warning. However, if you are concerned,  glyphosate can be largely avoided by choosing organically-grown foods . However, be aware that some "organic" processed foods, such as cereals, will contain glyphosate, likely due to cross-contamination of ingredients. 

When evaluating reports on glyphosate, it is important to distinguish between the concentration in a product, typically in ppb (1,000 ppb = 1 mcg per gram), and how much you would consume, i.e., the concentration times the grams in a serving.

Also see's Oat Cereals Review, which compares amounts of ochratoxin A (a potential carcinogen and kidney toxin) and gluten in popular products. Glyphosate was not tested in the Review, which was conducted prior to the classification of glyphosate as a probable carcinogen in the U.S., but levels would likely be similar to those reported above.

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Marsha16327   January 2, 2018
I can't believe there are still disbelievers in the science, given what we know about the toxicity of a chemical that is produced to kill. Many people have physiologies that do not allow them to detox these types of toxins easily or at all (I am one of them). The cumulative effect is what should be of concern. With the overload of toxins from all sources, our bodies can't keep up with the overload. What might be okay for some is harmful for others. Who wins?

Jeff16307   December 27, 2017
Some of the comments in this thread remind me of the same arguments made in the 1940’s by cigarette manufacturers and their allies; that there wasn’t enough poison in the average dosage of cigarettes to affect human health.

Just like the commenters back then, the people in this thread conveniently avoid talking about the cumulative effects of glyphosate and its long-term effects as well as wanting to err on the side of feeding poison to everyone while forcing people to prove that poison is dangerous.

They also fail to mention that the use of glyphosate only increases crop yields approximately 10%.

Their arguments are counterintuitive and exhibit a sociopathic tendency.

Robyn16207   November 15, 2017
Thank you to Consumer Lab for providing this article, the information you provide is greatly appreciated!

Stuart16198   November 13, 2017 should reconsider its "bottom line" that "glyphosate is a probable carcinogen." I doubt ConsumerLab has any evidence for this conclusion other than the IARC report from 2015, which is disputed by the vast majority of scientific findings around the world, including the very recent AHS finding, and which has also been called into serious question as a result of bias of a key participant. Unless there is other support that ConsumerLab can cite for this finding, to replicate the dubious conclusions of IARC risks perpetuating false beliefs that are contrary to science among your subscribers, and further jeopardizes the credibility of ConsumerLab (which I generally find to be excellent so far). It is very important that ConsumerLab reconsider and, as I urge, revise this conclusion for the sake of science and of the site's overall credibility.

Richard A16318   December 27, 2017
IARC is considered to be a very reputable and widely accepted source of information on carcinogens. Scientific risk determination is based on a weight of evidence approach, and the IARC, the AHS and all other studies and data must be considered together along with the quality of the studies themselves. Rarely is a single study considered alone when other evidence and studies are available. That being said, the jury is still out on glyphosate, its carcinogenicity and its other adverse effects.

Mike16193   November 12, 2017
I use glyphosate about once a year except for selective applications with a "weed wiper". Please show me actual proof that it causes cancer, the actual levels that it does, and a reasonable alternative, and I'll happily quit using it.

Jerry16189   November 12, 2017
This is all not true that is why people get cancer from it. They are all in bed and spread lies.   November 12, 2017
Hi Jerry - We are not "in bed" with any party here and are simply answering a good question with the current facts. We are all about providing solid, fact-based information. Our subscribers are largely individual consumers, and this is why they subscribe.

If information is published indicating more of a danger we will certainly include here.

In the meantime, it is certainly possible to largely avoid glyphosate if it is a concern by choosing foods not likely to contain it, as discussed above.

Mary16183   November 12, 2017
The above seems to be a very thoughtful and scientific article. Although each food item and/or supplement may not have enough glygosphate to be a concern, would there not be concernable amounts from a full day of food and supplements?   November 13, 2017
A good question. If you do the numbers, though, it seems highly unlikely that one could exceed the European limit. Assume that you ate exclusively the most contaminated oat cereal reported (1,670 mcg per gram in an instant oatmeal -- see the FDA presentation above) to provide all your energy, say 2000 Calories worth. That means you'd need to eat about 500 grams of food. This would yield about 8,350 mcg of glyphosate, which is still far below the European limit for an adult of around 34,000 mcg.

Steven16181   November 12, 2017
I'm surprised that California would set the limit so high, they should have placed it at Europe's level or below that.
Glyphosate is causing so many health problems and is toxic. Monsanto has caused more disease than any other comapny with it's glyphosate and GMOs.
In addition to a non GMO verified label we need a non glyphosate verified label.   November 12, 2017
The California limit is actually fairly stringent based on the current science.

Douglas16179   November 12, 2017
Why is Consumer Labs not aware of this.

Previously unreported court documents reviewed by Reuters from an ongoing U.S. legal case against Monsanto show that Blair knew the unpublished research found no evidence of a link between glyphosate and cancer. In a sworn deposition given in March this year in connection with the case, Blair also said the data would have altered IARC’s analysis. He said it would have made it less likely that glyphosate would meet the agency’s criteria for being classed as “probably carcinogenic.”   November 13, 2017
Hi Douglas - We are aware of that article, which is interesting, but does not negate any information we presented above in our answer. For those who have not read it, the article indicates that research shows no association between exposure to glyphosate and non-Hodgkin lymphoma, based on a study of U.S. farm workers and their families.

Martha16178   November 12, 2017
Glyphosates kill weeds by disrupting their shikamate pathway; Monsanto's claim that humans do not have this pathway was one of the arguments that ultimately caused the FDA to approve this poison. Directly, humans do not; however, the friendly little bacteria in our gut does and if you eat glyphosates, you will kill them. I know; it happened to me. After two years of intestinal problems, I went totally organic and it has totally cleared up.

Eileen16311   December 27, 2017
Thanks for your insight. I also agree that the jury is out on this one, and to be safe, we should be trying to stay away from it. I stopped using it even on weeds 3 years ago and got a "blow torch" for them instead.

Stuart16177   November 12, 2017
The only body in the world to conclude that "glyphosate is a probable carcinogen" is IARC. The integrity of IARC's report and conclusions has been prominently called into question. Not only EFSA but also EPA, the Canadian Pesticide Management Regulatory Agency, and others have concluded directly to the contrary that glyphosate is not a carcinogen. In addition, the Agricultural Health Study, conducted under the auspices of the National Cancer Institute, EPA and other bodies since 1993, reported on November 9 that there are no significant associations between glyphosate and incidences of cancer in a population of 89,000 farmers and their spouses. The "bottom line" should not be that "glyphosate is a probable carcinogen", but rather the IARC's conclusion (and the California listing which relies solely on the IARC report) is a politically-motivated outlier.

Al16206   November 15, 2017
The may be quite a bit more to it than whether it's a carcinogen. And politics do cut both ways, otherwise there wouldn't be lobbyists.

This CL Answer initially posted on 11/11/2017.

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