GMO crops - organ damage, fertility impact; DNA damage not ruled out

Why Mexico doesn't want U.S. corn

In a trade war with Mexico, U.S. agriculture and biotech industries, with corporatocracy backing, have insisted that GMO crops are safe and, therefore, Mexico must buy them under the terms of the USMCA (United States, Mexico, and Canada) agreement. Yet, Mexico, the “birthplace of corn,” has fought back against demands that the country accept American-grown GMO corn and plans to provide evidence that GMO corn is harmful with studies from its large GMO database when the stand-off is adjudicated by a special panel expected to convene in March 2024. (Mexico has also banned GMO soy.)

Concern about corn and soy stems from the fact that 92% of all corn and 94% of all soy[1] grown in the U.S. today are genetically modified crops. Commonly referred to as “Bt corn” and “Bt soy,”[2] they (along with other Bt crops) have been genetically modified to produce the Cry protein DNA of the bacteria Bacillus thuringiensis (Bt) which targets the larvae of particular insects, enabling the protein to replicate in the plants and destroy those pests before they can harm the plants.[3].

Mexico, while defending its own population, is actually alerting Americans to the potential dangers they face domestically. Farmers depend on corn and soy for livestock feed. Food manufacturers use corn and soy for numerous products that line supermarket shelves. Unless specifically identified as organic, it is all genetically modified.

Multiple studies refute industry claims of GMO safety

Misinformation propagated by GMO proponents

CONAHCYT, the Mexican government’s leading scientific body, has a large studies database backing up its claims.[4] Included in the database is an article titled “An illusory consensus behind GMO health assessment”[5] which demonstrates that misinformation about GMO crops is proliferated by GMO crop proponents who insist that the scientific consensus is that GMO crops are safe for health and the environment.

This article examines scientific reviews and papers on GMOs, compares the findings of professional societies, and discusses the treatment of scientists who have reported adverse effects in animal feeding experiments. This article concludes by exploring the role that politics and corporate interests have had in distorting an honest inquiry into the health effects of GMO crops.

The following are quotes from three of the studies cited in the article that demonstrate toxic effects on organs, reproductive effects, alteration of blood, biochemistry, and immunological parameters for humans and rodents eating GMO foods:

Health Risks of Genetically Modified Foods[6]

The results of most studies with GM foods indicate that they may cause some common toxic effects such as hepatic, pancreatic, renal, or reproductive effects and may alter the hematological, biochemical, and immunologic parameters. . . . The use of recombinant GH or its expression in animals should be re-examined since it has been shown that it increases IGF-1 which may promote cancer.

Morphological and biochemical changes in male rats fed on genetically modified corn[7]

The data showed several statistically significant differences in organs/body weight and serum biochemistry between the rats fed on GM and/or Non-GM corn and the rats fed on AIN93G diets [purified diets for laboratory rodents]. In general, GM corn sample caused several changes by increase or decrease organs/body weight or serum biochemistry values. This indicates potential adverse health/toxic effects of GM corn and further investigations still needed.

A long-term study on female mice fed on a genetically modified soybean: effects on liver ageing[8]

This study demonstrates that GM soybean intake can influence some liver features during ageing and, although the mechanisms remain unknown, underlines the importance to investigate the long-term consequences of GM-diets.

Damage to pancreas, liver, and testes

GM Watch editor Claire Robinson reviewed the findings of two studies, by Italian scientist Manuela Malatesta, on rats fed GMO soy.[9] Long-term feeding of GMO soy (up to 8 months) showed pancreatic damage and diminished function in the liver and testes.

In 2002 and 2003 the Italian scientist Manuela Malatesta published two groundbreaking studies showing damage to the pancreas of mice fed GM soybeans for long-term periods of up to eight months. The GM-fed mice also suffered damaged liver and testes function.

. . .

[T]he pancreatic studies were followed up a few years later in the 2008 study by Mexican researchers – who confirmed her findings.

Robinson qualifies the findings, suggesting that it is difficult to know if the damage was caused by the GMO diet and/or the “toxic glyphosate weedkiller” sprayed on them.

GM soy is one of the most widely grown GM crops in the world and accounts for over 90% of US-grown soy. It is engineered to survive being sprayed with toxic glyphosate weedkiller. It is not known whether the adverse effects associated with the GM soy diet in either study was caused by the GM crop or the weedkiller, or both.

DNA damage not ruled out

Robinson is not convinced that DNA damage does not or cannot occur or that foreign DNA won't be purposely inserted, reminding us that we have no assurances of safety since governments and biotech lobbyists are “mov[ing] to remove safeguards from a new experimental generation of GM foods and crops amid claims that they are safe:”

It's useful to remind ourselves of these studies as governments and GMO industry lobbyists move to remove safeguards from a new experimental generation of GM foods and crops amid claims that they are safe. Assurances that new GM gene-edited foods, crops and animals, unlike the first generation GM crops tested by the Mexican team, don't contain foreign genes or DNA are lies. Gene-edited GMOs can unintendedly incorporate fragments of foreign DNA in their genome, which can persist in the final product, or they can be contaminated by foreign DNA present in materials used in tissue culture. In addition, gene editing can be used to deliberately insert foreign DNA.

However, the risks of new GM gene-edited foods and crops are not confined to the insertion of foreign DNA, but can result from the most apparently small and simple gene "edit", the gene disruption type known as SDN-1, as a scientific review shows.

As far as we know, no one has carried out an animal feeding study with new gene-edited foods, crops, and animal products such as meat and dairy. So their safety profile remains unknown.

Increased death

IRT (Institute for Responsible Technology) identified studies revealing serious harms resulting from GMO diets[10] including:

  • toxic reactions in the digestive tract,
  • liver damage,
  • higher death rates and organ damage,
  • reproductive failures and infant mortality, and
  • farmer reports of livestock sterility and deaths.


BT toxins found in blood samples - study discredited by industry

Do BT toxins survive in the gut? A study found traces of the toxins in women's blood samples. Daily Mail Consumer Affairs editor Sean Poulter cited an independent study by doctors at the Department of Obstetrics and Gynecology, at the University of Sherbrooke Hospital Centre in Quebec, Canada[11] who studied the blood of 30 pregnant women and 39 non-pregnant women. Traces of BT toxins were found in the blood samples of:

  • 93% (28 out of 30) of pregnant women,
  • 69% (27 out of 39) of non-pregnant women, and
  • 80% (24 out of 30) of the umbilical cords.

Industry, which usually finances food safety studies, discredited this one.

Monsanto - disregarding inconvenient evidence?

Despite much evidence to the contrary, Monsanto asserts that its GMO corn is safe based on its contention that the Cry protein inserted into the corn through genetic modification [12] cannot react with non-target cells. In a 2015 report,[13] Monsanto scientists stated that the genetically modified produce is safe for livestock and human beings because,

[a]n essential component of the highly selective insecticidal properties of most Cry proteins is the requirement that the toxin interact with one or more specific receptors. Many studies have demonstrated that the GI-tract epithelial surface of non-target insects and mammals, including humans, lack specific high-affinity Cry protein receptors.

Monsanto relying on unproven theories

Scientists working for Testbiotech, an independent German institute, question Monsanto. They found (among other issues) that Monsanto's contention that Cry proteins only work in the presence of the receptor cells may be theory, not fact. Their 2017 paper[14] states that

there is also evidence that Bt proteins can exert toxicity by different modes of action, which are not as yet fully understood.

. . .

Certainly, the absence of specific receptors in mammalian species is not sufficient to conclude that Bt proteins are not toxic for them. Potential effects might be subtle and show up only after chronic exposure.

Effects of multiple modifications not studied

Testbiotech scientists also questioned the safety of stacking – including more than one modification in a plant – which Monsanto hadn’t studied. Some Bt crops, such as corn and soy, called Roundup Ready, have also been modified to resist Monsanto’s glyphosate Roundup weed killer.

What about glyphosate?

Mexico and the U.S. are also arguing about glyphosate. Mexico does not want to buy it from the U.S. citing safety risks; the U.S. says it is safe and therefore Mexico must accept Monsanto's glyphosate weedkiller according to the USMCA trade agreement.

As Claire Robinson noted in her review of GMO studies, it is not clear if observed damage is caused by genetic modifications, by the toxic glyphosate sprayed on the crops, or both. Mexico also has a database of glyphosate studies which it will reference to prove the weedkiller is toxic when the dispute is adjudicated in March 2024. Frontline News will review select studies in the final installment of this series.

See our additional coverage of the trade dispute:

Footnotes

[1]

Center for Food Safety and Applied Nutrition. “GMO Crops, Animal Food, and Beyond.” U.S. Food and Drug Administration, FDA, www.fda.gov/food/agricultural-biotechnology/gmo-crops-animal-food-and-beyond

[2]

“Bt” is the acronym for the Bacillus thuringiensis Cry and Cyt protein families, a diverse group of proteins with activity against insects of different orders - Lepidoptera, Coleoptera, Diptera, and also against other invertebrates such as nematodes. (Bravo, Alejandra, et al. “Mode of action of bacillus thuringiensis cry and cyt toxins and their potential for insect control.” Toxicon, vol. 49, no. 4, 15 Mar. 2007, pp. 423–435, https://doi.org/10.1016/j.toxicon.2006.11.022 )

[3]

Bessin, Ric. “Bt-Corn: What It Is and How It Works.” Martin-Gatton College of Agriculture, Food and Environment, University of Kentucky, 2019, https://entomology.ca.uky.edu/ef130

[4]

“Documentos y Actividades En Bioseguridad.” CONAHCYT, Gobierno de Mexico, https://conahcyt.mx/cibiogem/index.php/sistema-nacional-de-informacion/documentos-y-actividades-en-bioseguridad

[5]

Krimsky, Sheldon. “An Illusory Consensus behind GMO Health Assessment” (PDF). ResearchGate, Science Technology & Human Values 40(6), Aug. 2015, https://www.researchgate.net/publication/282485442_An_Illusory_Consensus_behind_GMO_Health_Assessment

[6]

Dona, Artemis, and Ioannis S. Arvanitoyannis. “Health Risks of Genetically Modified Foods.” Critical Reviews in Food Science and Nutrition, vol. 49, no. 2, 2009, pp. 164–175, https://doi.org/10.1080/10408390701855993

[7]

Gab-Alla, et al. “Morphological and Biochemical Changes in Male Rats Fed on Genetically Modified Corn (Ajeeb YG)” Research Gate, Journal of American Science, Aug. 2012, https://www.researchgate.net/publication/235256863_Morphological_and_Biochemical_Changes_in_Male_Rats_Fed_on_Genetically_Modified_Corn_Ajeeb_YG

[8]

Malatesta, Manuela, et al. “A long-term study on female mice fed on a genetically modified soybean: Effects on liver ageing.” Histochemistry and Cell Biology, vol. 130, no. 5, 2008, pp. 967–977, https://doi.org/10.1007/s00418-008-0476-x

[9]

Robinson, Claire. “GM Soy Injures the Pancreas, Rat Feeding Study Shows.” GM Watch, 15AD, https://gmwatch.org/en/106-news/latest-news/20129-gm-soy-injures-the-pancreas-rat-feeding-study-shows

[10]

“Genetically Modified Foods: Toxins and Reproductive Failures.” Institute for Responsible Technology, 15 Mar. 2020 https://responsibletechnology.org/genetically-modified-foods-toxins-and-reproductive-failures/

[11]

Poulter, Sean. “GM Food Toxins Found in the Blood of 93% of Unborn Babies.” Daily Mail Online, Associated Newspapers, 20 May 2011, https://www.dailymail.co.uk/health/article-1388888/GM-food-toxins-blood-93-unborn-babies.html

[12]

See footnotes 2 and 3

[13]

Koch, Michael S, et al. “The Food and Environmental Safety of Bt Crops.” Frontiers in Plant Science, U.S. National Library of Medicine, 29 Apr. 2015, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4413729/

[14]

Then, Christoph, and Andreas Bauer-Panskus. “Possible Health Impacts of Bt Toxins and Residues from Spraying with Complementary Herbicides in Genetically Engineered Soybeans and Risk Assessment as Performed by the European Food Safety Authority EFSA.” Environmental Sciences Europe, U.S. National Library of Medicine, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5236067