Dr. Robert Kremer: GMOs, Glyphosate and Soil Biology

 Dr. Robert Kremer is a Professor of Soil Microbiology at the University of Missouri and is recently retired after a 32-year career as a microbiologist with the U.S.D.A.  He spoke with Food Integrity Now about the problems he has studied over the past 18 years with transgenic crops (GMOs) and Glyphosate. Glyphosate the active ingredient in RoundUp is the most widely used herbicide in the world. Eighty percent of all GMO crops are engineered to tolerate Glyphosate.

Dr. Kremer first became concerned with GMOs and Glyphosate in 1997 when he and his colleagues observed that plants became overly infested with soil fungi during the dying process from the effects of Glyphosate. Knowing that some of the soil fungi were natural biological control agents for some of these pests, including soybean cist nemotode (parasitic roundworm), they looked at these transgenic crops (GMOs) which were receiving Glyphosate and looked at the root system and found an increase in soil fungi. They noticed that every time that they checked this GMO crop that the roots were loaded up with the fungus, Fusarium. Fusarium is a fungus that can be potentially pathogenic. He said his concern was that here we have this new release of crops that are tolerant to Glyphosate yet their root system are piled up with this fungi. He has evaluated several GMO crops over the past 17 years and continues to see increased fungi on their roots.

Dr. Kremer explained some of the ways that Glyphosate kills a plant. This chemical inhibits a particular enzyme which is involved in the synthesis of certain amino acids. It also shuts down the shikimate pathway and shuts down protein synthesis. Therefore, the plant can’t produce defense mechanisms and is susceptible to pathogens and can become very infected with these opportunistic pathogens and ultimately become diseased. Glyphosate is also a very strong chelator and can immobilize nutrients like manganese, iron, zinc. It binds up these nutrients and makes them unavailable to the plant. This is very detrimental to plant growth.

 Since we have evidence of Glyphosate being found in our gut where the bacteria do have shikimate pathways, it makes sense why we are seeing the increase of many allergies and diseases that originate in the gut where 80% of our immune system is in our microbiome. The chelation process of Glyphosate can make some of the good gut bacteria unavailable and as Dr. Kremer explained can shift the balance of the microbial population in our gut. Keep in mind, Glyphosate has also been found in our urine, human breast milk, and in our blood. The biotech industry claims that Glyphosate degrades in the soil and it cannot affect humans because we do not have a shikimate pathway–however the bacteria in our gut does have this pathway.

Monsanto, the maker of RoundUp with its active ingredient Glyphosate, makes a claim that Glyphosate is neutralized or degrades in the soil. Dr. Kremer shared information on some of the factors that can affect how Glyphosate reacts with the soil. These factors affect persistence, availability and degradation of Glyphosate in soils. He talked about a few of these factors including the soil’s pH and the amount of phosphorus in the soil. In our interview, he only spoke about a few of the ways Glyphosate will react with the soil but there are several other factors which include, soil mineralogy (texture), soil nutrient status, soil surface vegetation residue, type of crop management system in place (cover crops, crop sequence), soil oxygen status, herbicide formulation and components (surfactants), soil organic matter content, and the composition of soil microbial community.

 Dr. Kremer further shared his thoughts on the big claim of the biotech industry that we need GMOs to feed the world. He also discussed their claim of decreased use of pesticides. There has been a 527 million pound increase in pesticide use since the introduction of transgenic crops.

Recently, the WHO (World Health Organization) stated that Glyphosate “probably” causes cancer. Dr. Kremer discussed the need for more independent testing on Glyphosate and is hopeful that WHO’s recent claims would prompt such further independent testing.

Listen to this very informative interview that connects some of the dots as to how GMOs and Glyphosate effect plants and human health. Click on the link at the bottom of the page to listen:

Dr. Robert Kremer Research Papers

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  1. Great Article. This is the kind on information we need to know and indeed, everyone in the world needs to know so we can stop this madness.

    I would like to make a question although I more or less can guess the answer, but a confirmation would help me more.

    As Dr. Kremer explained, Glyphosate ties up or inactivates several minerals. Would then any of those mineral be lacking in the final product/crop so that it would not be “essentially equivalent” to the natural produce/crop?

    I would appreciate your answer,

    Hector Vargas

    1. Hector, i would answer you my estimation, but then i would love to know what answer Dr Kremer replies with, if you would post it here too. I would suppose that it is not likely that chelation within the plant by glyphosate would affect the nutritional content of the food so much, because of the very small amount that is applied, compared to the amount of biomass of the plants. However, there is a possible causal connection that may affect nutrition value of the plant more than this, which is the effect on the endophytic bacteria within the plant. If you search you can find a paper called “Isolation and characterization of endophytic bacteria from soybean (Glycine max) grown in soil treated with glyphosate herbicide” from 2005, which shows that glyphosate has differential effect on different species of bacteria within the soybean plant. Endophytic bacteria is sort of the “gut microbiome” of the plant kingdom. This may affect the balance of nutrition that makes its way into the plant seeds that we eat, for maize and soybean. This is one more reason to be suspicious of glyphosate. All plants have endophytic microbes, bacteria and fungus that have complex relationships to the plant, just like humans have microbiomes, which are all affected by glyphosate in ways we do not understand, because Monsanto has not done the studies, which i would call a case of serious criminal negligence in pursuit of profit.

  2. Indeed, i have also worked as a microbiologist studying microbial communities, albeit for a lot shorter time period than Dr Kremer, and i have recently been studying glyphosate’s mode of action on plants, and also became very concerned about the potential disruption of the mammalian gut microbiome, by selective pressure exerted by the blockage of the shikimic acid pathway. Each microgram of glyphosate – and we get micrograms daily in a typical diet – is anough for 35 molecules of glyphosate for each of the 100 trillion human gut microorganisms. This is enough to affect them, and we get it daily. Plant cells studies have shown that cells overexpress the whole shikimic acid pathway when their EPSP synthase is blocked by glyphosate, and this means that the cell expends more energy and still never gets enough of the aromatic amino acids, thereby starving and choking the cell. It cannot compete with other microbes like those in the Pseudomonas family, which can be opportunistic causes of ailments in a gut where other microbes are weakened. It’s not a good thing. As i looked into it, i then realized that Monsanto never actually studied this, at all. They intended to release a chemical into the general foodstream worldwide, and they *never* studied the effects on the gut microbiome community in any detail that would be required to show whether it causes any disruption or profound changes — or even small changes, at that. Don’t you think that would be a basic level of responsibility on their parts? I certainly do, and i hold that they are guilt of criminal negligence, for turning the humans of the Earth into subjects for a massive chemical exposure experiment.

    1. T. Matthew Phillips has a class action suit against Monsanto for falsely labeling their products which say glyphosate targets an enzyme found in plants but not in people or pets. He may be the guy you’d like to talk to.

  3. One should also learn about endophytic bacteria and the effect of glyphosate on them. This is probably related to the effusion of root fungus as well. Here’s a paper relevant to endophytic bacteria in soybean, and glyphosate exposure. I hope that the dialog about the effects of glyphosate on microbial communities, within plants, within mammals, and in the soil, gets louder very fast, and causes Monsanto to have to face serious questions about the safety of their product.

    Plant and Soil
    June 2005, Volume 273, Issue 1-2, pp 91-99
    Isolation and characterization of endophytic bacteria from soybean (Glycine max) grown in soil treated with glyphosate herbicide
    Júlia Kuklinsky-Sobral, Welington Luiz Araújo, Rodrigo Mendes, Aline Aparecida Pizzirani-Kleiner, João Lúcio Azevedo

  4. Instead of labeling GMO produce and products – the battle cry should be BAN Roundup and all glyphosate products now that the WHO has put out an international group of scientists’ determination. Monsanto depends a lot on Roundup sales. This would cripple them more than labels, an almost useless weapon in a nation where Monsanto rules the government.

  5. Irritable Bowel Syndrome, of which gluten intolerance can be a part, is rising particularly in Western nations. Is this because of awareness, an ageing population, wealth, or because of the amount of glyphosate we now ingest?

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