France: Study Shows GM Corn Fed Rats Display Higher Tumors Levels

Guillaume Malaurie reports that [fr] a team of French researchers led by Pr. Gilles-Eric Séralini found that laboratory rats fed with a steady diet of Monsanto genetically modified corn displayed higher levels of tumors and multiple organ damage than those of control rats.  The researchers worked in quasi-clandestine conditions [fr] to prevent interference with their research.


  • BadScience

    Unfortunately these studies were highly flawed and have been heavily criticized for “bad science’ by peer reviewers. The most glaring flaw was they didn’t even have a real control sample, and they used rats that had genes with high propensity for tumors. They also didn’t even control the total amount of food consumed or food contamination in the study.

    Here are some of the flaws of the paper published by the French and Norwegian as pointed out by peer reviewers:

    – The population of rats used have a high propensity for tumors.
    – There were only 20 rats in the control group, and 80 in the exposure groups, an atypical asymmetry.
    – There was no dose response at all – which is a critical component of demonstrating a toxic effect.
    – The researchers did not control for total amount of food consumed, or fungal contaminants, both of which increase tumors in this population of rat.
    – The data reports that “some” of the test groups had a higher tumor incidence, while others did not – sounds suspiciously like cherry picking the data.
    – The statistical analysis done by the team was atypical, characterized by nutrition researcher Tom Sanders as ”a statistical fishing trip,” while a more standard analysis was excluded.
    – Exposure to GM corn or the herbicide Roundup had the same negative effects. It is inherently implausible (admittedly not impossible) for such distinct mechanisms to have the same effect.

  • Alex Nuta

    Scott Kinnear of the Safe Food Foundation stated that: “It’s what we’ve expected before publication and it’s what’s happened every time a serious scientist has brought out adverse results about genetically modified crops, they are attacked and vilified for that research. There is a very strong campaign out there to discredit the research and people should be aware of that campaign when they look at the results of this study.”
    I’m sure there will be studies that will contradict this one shortly, as soon as GMO companies can commission them, and reassure us that just because it kills rats doesn’t mean it will do any harm at all to our children. They may also suggest that it’s only that particular engineered corn species that has a problem and not the dozens of other species of corn and other products that they’re already selling us directly or indirectly on a daily basis.
    If you’re scientifically minded and want to read their findings, here is the link to the final paper PDF:
    As a side note. I just did a Google search and dozens of articles have popped up in the last week or so, almost all of them from the US and many of them turned this story to “Controversial study”, “Study draws skepticism” and “The debate rages on”. DON’T BE FOOLED. These doubt-inducing stories are written largely by Pro-GMO authors for the benefit of a non-science literate public. But don’t believe me. Read the study. Read information that comes from outside the US. Make up your own mind.

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