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Study: Herbicide and GM Corn May Cause Tumors, Early Death

New research out of France has linked both an herbicide and a genetically modified corn to organ damage, tumors and early death among rats, prompting a call for greater regulation of GM foods among sustainable agriculture advocates.

The study – published Wednesday in Food and Chemical Toxicology – found that rats who were exposed to Roundup, a weed killing herbicide, and rats who were fed Roundup-resistant corn developed mammary tumors, kidney and liver damage and died earlier than those in the control group.

According to the authors, this is the first study to examine the long-term effects of genetically modified Roundup Ready corn, or NK603, which is produced by biotech corporation Monsanto and has been approved for use in both the European Union and the United States.

Previous studies have examined the effects of NK603 on animals over the course of 90 days, while this study looked at a two-year period.

“There were no adverse effects in a 90-day feeding study on rats with NK603 maize grain…” says the EFSA GMO Panel in its scientific opinion on the corn. “The EFSA GMO Panel is of the opinion that maize NK603 is as safe as conventional maize. Maize NK603 and derived products are unlikely to have any adverse effect on human and animal health in the context of the intended uses.”

The French study, however, found a series of adverse health effects in rats fed with the corn.

In this study, conducted on 100 female and 100 male rats, the animals were given either Roundup-resistant corn, the Roundup herbicide or both. Animals in all three of these test groups experienced adverse health effects and died earlier than rats in the control group, who were given regular corn and plain water.

“The results were really alarming,” said Professor Gilles-Eric Seralini, co-director of the Risk Quality and Sustainable Environment Unit at the University of Caen, France and the study’s lead researcher. Mammary tumors began to appear in females after 4 months, he said, and “after one year there was a high increase of a number of (kinds of) tumors. Almost every female rat had two or three tumors,” said Seralini in a Wednesday press conference.

Up to 50 percent of males and 70 percent of females fed with GM corn died before their deaths could be attributed to normal aging, compared with 30 percent of males and 20 of females in the control group who died prematurely.

Tumors grew more frequently and rapidly among most test groups than among the control group. After 23 months, 50 to 80 percent of the treated female rats (percent depending on group) had developed tumors, while 30 percent of female control rats had tumors. The group treated with Roundup showed the greatest incidence of tumors. Of the females in this group, 80 percent developed at least one and up to three tumors.

Treated males developed tumors largely in their kidneys and skin, and were two times more likely to have a tumor during the 23rd month than control males. Treated males also suffered liver damage at greater rates.

“The results of the study presented here clearly demonstrate that lower levels of complete agricultural glyphosate herbicide formulations (such as Roundup), at concentrations well below officially set safety limits, induce severe hormone-dependent mammary, hepatic (liver) and kidney disturbances,” write the authors.

Test rats were given varying doses of Roundup in their water and NK603 corn in their feed. The lowest doses administered in the study were lower than levels allowed in both the EU and U.S., according to the study.

The lowest treatment level of Roundup alone was at the “usual contaminating level of tap water,” explained Seralini.

Test animals experienced severe adverse health effects even at these lowest levels. The authors say this result suggests that both products cause a hormonal imbalance.

“Our data show that, as is often the case for hormonal diseases, most observed effects in this study were not proportional to the dose of the treatment.”

“This implies that both the NK603 maize and R(oundup) may cause hormonal disturbances in the same biochemical and physiological pathway,” concludes the study.

The fact that groups treated with GM corn alone reacted similarly to those treated with the only the herbicide was surprising, says Seralini.

“We were really interested by the results of the GMO alone that was not treated with Roundup,” said Seralini. “The groups with the GMO surprisingly also had hormonal disruptions and there were also mammary tumors.”

After a detailed analysis of the chemical composition of the animals’ diets, researchers found that two compounds in plants that protect animals against mammary tumors and toxicity of the kidney and liver were reduced to 51 percent with the consumption of the GM corn. They concluded that an enzyme that is over-expressed in 80 percent of GMOs was causing this effect, explains Seralini.

An estimated 70 percent of corn grown in the U.S. is Roundup Ready.

According to Monsanto’s safety assessment, NK603 is corn into which DNA is inserted to make the plant resistant to the harmful effects of Roundup. Prior studies have shown that the CP4 EPSPS proteins expressed in Roundup Ready corn do not produce toxicity in mice, nor are they similar to known allergens or toxins, and they are rapidly digested in vitro.

Tom Sanders, head of the nutritional sciences research division at King’s College London, expressed concern over the methods used in the French study.

“This strain of rat is very prone to mammary tumors particularly when food intake is not restricted,” said Tom Sanders, head of the nutritional sciences research division at King’s College London according to Reuters wire service. “The statistical methods are unconventional … and it would appear the authors have gone on a statistical fishing trip.”

Call to Action

The authors of the study, along with the Sustainable Food Trust – a nonprofit global group that promotes sustainable agriculture – say these results highlight a need to further supervise the approval and sale of genetically modified foods worldwide. The NGO stated the following in a press release Wednesday:

In light of these findings the Sustainable Food Trust sees the call to action as:

- A pre-cautionary review of the regulatory framework for testing Pesticides and GM foods

- The requirement for foods containing GM ingredients or their derivatives, or from animals fed on a GM diet, to be clearly labeled

- Further independent research exploring the potential human health effects of consuming these products.

The fact that GMO foods are not labeled in the U.S. is “in my opinion a very severe problem,” said Seralini during the Wednesday press conference. Consumers should have the freedom to know what is in their foods, he says.

“In Europe we have this labeling and it enables us to avoid these compounds if necessary,” he said.

This study comes just before California is set to vote on whether or not to mandate labels for GMOs, which will be on the ballot as Proposition 37 this fall.

“The results of this study are worrying,” said Proposition 37 California Right to Know Campaign Manager Gary Ruskin in a statement Wednesday. “They underscore the importance of giving California families the right to know whether our food is genetically engineered, and to decide for ourselves whether we want to gamble with our health by eating GMO foods that have not been adequately studied and have not been proven safe.”

Seralini says the results of his research also point to the need to test the effects of GMOs for two years – the average lifespan of a rat – rather than for 90 days, since the tumors found in this study appeared after four months had passed.

He also recommends that the U.S. government rely less on company tests when making regulatory decisions about the company’s products.

The study was supported by the independent research organization, CRIIGEN and was published in the Food and Chemical Toxicology. It is available on the Sustainable Food Trust’s website.

© Food Safety News
  • Donnie

    Geez… I’m glad I’m allergic to corn. I don’t even feed anything containing corn to my dog. I avoid the other GMO crap, too.

  • Phil

    I am not someone who believes every study that comes out. It is amazing how each study comes to a different conclusion based on who pays for it. What I do believe is that companies have a responsibility to provide all reasonable information to their consumers. We require allergen information for our consumers. If the consumer has concerns about GMO products, antibiotic use, country of origin etc. we should be willing to provide them this information. Understanding that there is only so much that can be put on a label, there are many other ways to provide this information. Knowledgable comsumers are the best customers I work with.

  • da

    Regarding the “fishing trip” comment by Mr. Sanders, if Columbus only sailed for 90 days, then he would have concluded the earth was flat.

  • keene observer

    Wait a minute…how the heck did 30% of the normal rats get tumors and how did 20-30% of the normal rats die prematurely?
    Those are epidemic incidences in themselves. Something is very seriously wrong in the background of this little experiment to cause that.
    If the researchers were evaluating GM corn and Roundup as potential cures, well they didn’t work and no one expected them to. Concluding sick rats are made even sicker by GM corn or Roundup isn’t very informative at all. Maybe there should have been test groups with organic fruit, some with vitamin supplements and maybe some with raw milk to make sure those don’t make sick rats sicker too. What do you want to bet you could have fed a group of those sick rats with mother’s own breast milk and still have an even chance of finding more tumors or bigger tumors or more premature deaths?
    Whoever paid these silly damned Frenchies to hoax us should demand their money back. One more insult to good honest science, as if ordinary people need any more incentive to distrust competent scientists. Luddites are not refuting science so much as they are sodomizing it in this case. So sad.

    • sunny

      20-30 percent of rats in the control group died before their deaths could be attributes to normal aging. so, that is not so different from humans’ life. Not everyone dies of old age. the fact is those numbers went UP significantly in the groups of rats who were fed the GMO corn. A significant outcome, I would say.

  • John

    Donnie, do you eat beef or chicken or pork? Those animals are fed corn, and you have no way of knowing that much of it may be gmo corn. Do you eat any store-bought ready-made items, such as bread, deserts, ice cream, soda, pizza, etc etc etc? Many of those items contain corn syrup, and you have no way of knowing how much of it came from gmo corn. The effects of the toxic corn may not end with the first creature to consume it. Might the harmful strands of genetic information continuously make its way across the entire food chain, similar to how heavy metals continuously build up from small fish to big fish to people?

  • Donnie

    Gee, John, did you not notice that I said I am ‘allergic’ to corn, and have to avoid it. I also have Celiac, so I do not eat bread, pizza, cookies, etc. No corn syrup for me, because it was the first thing I reacted to when I was given formula with it after I was born. I eat organic foods for the most part. Very little organic turkey and beef. No chicken, pork or other meats. Organic milk, butter and eggs. Since I am anaphylactic to corn, I must avoid it. GMO or not, corn is pure poison to me and I have to avoid it as much as I possibly can. Without proper labels for corn it is hard to do. Especially when unlabeled corn is used for processing and packaging of foods. Having Celiac and food allergies means that I must be very careful about any foods I eat, to avoid further damage to my system. I don’t care what other people eat, I am concerned about me, and my family. If anyone wants to eat GMOs, corn, trans-fat, or anything else that is fine with me.

  • federal microbiologist

    [It’s great that there is a link to a pdf of the paper at the Sustainable Food Trust’s website, obviating the need to go to the Elsevier site and pay $31.50 to purchase a pdf.]
    The paper by Seralini et al. didn’t appear in what one would consider to be a ‘top-tier’ journal (e.g., Environmental Health Perspectives) but the data seem credible to me.
    One of the ‘predictable’ criticisms of the article is made by a Tom Sanders, a professor of nutrition at King’s College in London. Sanders argues that the strain of rats used in the study (Sprague-Dawley) are naturally prone to develop cancer / tumors. Sanders insinuates that use of this strain of rat invalidates the study.
    However, as Seralini et al. point out, the Sprague-Dawley strain was the same used by Monsanto’s own researchers in their studies of the consumption of Roundup Ready GMO maize (Hammond et al., Food Chem Toxicol., 2004, 42(6): 1003 – 1014). The difference is, the Monsanto researchers only monitored their rats for 90 days. According to the observations of Seralini et al., tumors did not begin to appear in their treated (i.e., ingesting GMO maize and/ or RoundUp / glyphosate) rats until 4 and 7 months into the study for male and female rats, respectively. So the study by Hammond et al conveniently ended before cancers may have appeared in their test animals.
    And, even if the Sprague Dawley strain is prone to developing tumors, it doesn’t negate the fact that the treated rats developed tumors at a markedly higher rate than animals not fed GMO / RoundUp. Accordingly, Sanders’ criticism is itself flawed.
    Another of the critics of the paper by Seralini et al. is Mark Tester, of the Australian Centre for Plant Functional Genomics at the University of Adelaide. Tester is a plant physiologist, not a toxicologist or cancer researcher.
    Tester’s web page remarks upon his “….successful interactions with multinational companies such as Monsanto, Syngenta, Bayer and Pioneer-DuPont.”
    Tester argues that if the consumption of RoundUp Ready GMO maize “….. did indeed trigger increased rates of cancer in humans, why aren’t the North Americans dropping like flies? GM has been in the food chain for over a decade over there – and longevity continues to increase inexorably.”
    This criticism is disingenuous. It’s true that longevity is increasing, but since 1975, the incidence of cancers in the US population has been increasing (1). The reason that mortality associated with cancer is not affecting longevity, is a testament to advances in cancer screenings, prevention programs, and advances in cancer treatments. [Although people who deal with the aftereffects of chemo, radiation, and surgery may argue that their quality of life has been greatly affected.]
    It’s also disingenuous of Tester to use the phrase ‘dropping like flies’. Cancer is a chronic condition and its lethality (for most malignancies) takes years or even decades to be manifested.
    Needless to say, researchers funded by the agrochemical industry are even now being mobilized by their sponsors to levy a tsunami of criticism at Seralini et al.
    Their tactics will include mass emails / mails to the Journal editor, demanding that the data generated by Seralini et al exemplify ’bad science’ and the paper should be retracted. As well, they will insist that the Journal published their letters attacking the validity of the study by Seralini et al; these letters will contain spurious, contrived criticisms of the work by Seralini et al., in the hope that by throwing enough mud, ‘some will stick’.
    These are tactics the supporters of GMOs have employed in the past to try and discredit researchers who dare to confront corporate attitudes about ‘safety’ and GMOs (2).
    However, I get the sense that Seralini and his colleagues are quite comfortable in confronting these attacks. It will help that, over the past 7 – 8 years, the wider scientific community has become aware of the malicious nature of the way the agrochemical industry attempts to discredit research they are unhappy with.
    Things are going to get interesting……
    (1) http://onlinelibrary.wiley.com/doi/10.3322/caac.20138/pdf
    (2) GMO Myths and Truths, by Antoniou et al., Earth Open Source, June 2012, pp. 29 – 33 (pdf free and available from the Earth Open Source website)

  • John K. Harvey

    French news this morning announced that rats may have been using cell phones while researchers were away, completely ignoring the advice of Professor Seralini. One of the reported text messages from “Ratatouille” (we won’t use his real name) was, “Connard nous fait bouffer que du maïs et boire du Roundup. Il est con et méchant.”

  • http://www.writemypapers.org/ writemypapers.org

    Now more number of peoples are interested in having genetically modified
    foods as they are available in huge stocks. But recently in a survey it
    was found that people having genetically modified crops are having more
    risk of getting tumors and organ damage. The best example of such a
    crop is genetically modified corn. So it is better to avoid these types
    of crops.

  • pheighdeaux

    The large numbers of scientific studies do not back up the rumors that GMO’s are dangerous. While I personally think Monsanto is a detestable corporation I cannot condone the use improperly conducted scientific surveys that use correlation to insist causation.

    If GMO’s as a whole are dangerous there would be far greater conclusive evidence of this. Thus far this is not the case.

    Again, Monsanto is detestable and should be reigned in, but GMO’s are not all made by Monsanto. The benefits of GMO crops to ending world hunger are too great to let these biases against one corporation get in the way of staving off global starvation.

  • David

    What is wrong with the study, at least as far as I have read is the rats used are prone to develop tumors without any outside dietary change or help. Seems the study conclusions were predetermined before the study was under way. The EU ultimately determined the study was flawed an is on record stating there is no real difference in the probability of developing cancer or other illness from foods grown from GMO / GE seeds.

  • Nick Cainski

    Why are these gmo’s different enough to need a patent yet not different enough to need a label?
    Lets have a win win and label all gmo’s that way those wanting them can find them easier and those like me that do not want them can avoid them!