Update on Greenpeace Claim that Biotech Corn is a Mouse Contraceptive


corn condom

Back in November I blogged about an Austrian government "study" that found that mice fed pest and herbicide-resistant biotech corn had fewer surviving babies. As I noted at the time:

(1) This is classic case of "science by press release." The "study" may be valid, but it has not been "published" nor has it been peer-reviewed; and (2) Greenpeace backed similar controversial claims by other researchers that genetically modified soybeans harmed the fertility of mice that were later debunked. (For more details see also here.)  

The July issue of Nature Biotechnology has a good news story about the how various European governments distort science in order to mollify the anti-biotech sentiments of environmentalist ideologues. The article updates where the Austrian mouse study stands:

…Jürgen Zentek and colleagues at the University of Veterinary Medicine in Vienna launched a feeding study in mice to assess health over generations. The aim of the study was to assess the health effects of a variety of GM corn carrying two transgenes-cry1Ab from Bt and the gene encoding 5-enolpyruvylshikimate-3-phosphate synthase from Agrobacterium sp. CP4 (CP4 EPSPS), which confers tolerance to glyphosate herbicides. Although the authors stated that "no negative effects of GM corn varieties have been reported in peer-reviewed publications," they wanted to assess health effects over several generations-something that has rarely been studied.

The researchers used three different experimental designs: a multigeneration study in which they bred laboratory mice over generations; a continuous breeding study in which they bred the same pair of mice and assessed the health of each subsequent litter; and a lifetime feeding study in which the health of mice fed the GM corn variety was compared to that of mice fed an isogenic (genetically identical) variety.

The only statistically significant finding came from the continuous breeding study. After the first litter, mice fed GM maize gave birth to fewer pups in each subsequent litter, and the average litter weights of pups in the GM group also decreased over time.

Although the results from the first arm of the multigeneration study (in which mice from each generation were bred with each other) were not statistically significant, the authors did report that the number of pups weaned, the average litter size and the weight at weaning tended to be lower in the GM group than in the group fed the isogenic maize variety. They also found that more pups died in the GM group. They reported that these differences were consistent over generations, but were not significant because the intragroup variability was very high.

The study, funded by the Austrian Ministry for Health, Family and Youth, wasn't published, nor was it peer reviewed. Rather, the results were announced at a press conference last fall. Greenpeace issued a press release touting the study: "Forget condoms-eat GM maize," read the headline. Other anti-GM groups also jumped on the news, and the internet was awash with stories touting the new study and its frightening findings. In its release, Greenpeace demanded a worldwide recall of all GM foods and crops, stating: "GM food appears to be acting as a birth control agent, potentially leading to infertility."

Monsanto, the producer of MON810 maize, almost immediately responded. Although they commended the study design, they criticized the data: "This report lacks sufficient experimental details to fully interpret the results and contains a number of errors that make it unsuitable for risk assessment and/or regulatory purposes," they announced in a press release.

Their criticism focused specifically on two major flaws. First, the authors did not use historical controls or reference groups throughout the study when comparing groups of mice. Without a proper control group of mice to assess natural variability in fertility, it's difficult to say how much of the fertility decline was caused by diet alone. In addition, the authors used inconsistent calculation methods, did not use standard units in some calculations and also miscalculated some data. And even when the calculations were corrected, the lack of a control group made the results impossible to interpret, Monsanto argued.

Monsanto's criticisms have been confirmed and elaborated upon by several scientists. At Monsanto's request, James Lamb, executive vice president of the Weinberg Group, a multinational regulatory consulting firm, wrote a review in which he concluded: "When properly analyzed, these data do not appear to support an effect on fertility or reproduction from consumption of GM corn". Lamb was the researcher who had originally developed the continuous breeding study design, at the Research Triangle Park, North Carolina-based U.S. National Toxicology Program during the 1980s.

But the authors aren't to blame, says Klaus Ammann, emeritus professor at the University of Bern in Switzerland. They are merely the latest victims of what has become the political gerrymandering of science to bolster and support anti-GM sentiment in Europe.

"The Austrian government had exhausted all legal avenues to ban cultivation of GM crops," Ammann says. "The Ministry of Health decided to avoid the peer-review process and announce study results at a conference, hide the data from scientists, and let the activists run amok with the help of uncritical media."

Indeed, in the ensuing months the Austrian government has backpedaled. The Ministry of Health responded to a request to interview Zentek or other authors with the following: "We asked the scientists to reevaluate their statistical analysis. Additionally the external evaluation will soon be started. I kindly ask you to wait with your proposal until the reevaluation is completed."

The mouse study is a prime example of governments' "misuse of science" to support political ends, says Jörg Romeis, an ecologist at the Agroscope Reckenholz-Tänikon Research Station in Zurich, Switzerland.

Of course, the mouse "study" is a success from the point of view of Austrian politicians since biotech corn is still banned in that country. I will let Reason readers know the results of the external evaluation when they are reported. 

I highly recommend reading the whole Nature Biotechnology article to get a better sense of to what lengths anti-biotech environmental activist groups will go to find and cherry-pick data to attack the overwhelming scientific consensus that current biotech crops are safe for people and the environment. 

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22 responses to “Update on Greenpeace Claim that Biotech Corn is a Mouse Contraceptive

  1. Grain that acts as a contraceptive on grain-eating rodent pests?


    (yeah,I’m missing the “point”but so what?)

  2. I have the internet so I’ve seen plenty of ear-of-corn insertions(usually multi-colored Indian corn).They don’t use condoms.

  3. What # said.

  4. Some butter would make that go down a lot easier.

  5. A single link is as good as twelve paragraphs.

  6. We must all starve so that mice can keep their testicles in good working order.

  7. “We must all starve so that mice can keep their testicles in good working order.”

    Am I the only one who thinks of Tony when I read this?

  8. I think “SOS” must stand for “Save Our Sophism”.

  9. Wow what a great explanation of the problems associated with global warming research err I mean GM research.

    Sorry hard to keep all the phony sciences separate.

  10. Old Chinese Sayer: The Nature Biotech article is long and I didn’t want to force hardworking busy H&R readers to go searching for the relevant sections.

  11. While the organic movement is (now) largely about aesthetics and status seeking, the anti-GM movement is really about quasi-religious nature worship a nd fears of “playing god”. The anti-GMO activists don’t like it largely because it smacks of sacrilidge to tamper with the “mysteries of life”, and have simply concocted some pseudo-scientific bullcrap to give cover to it. I think at some level they are embarrassed by the similarity of their reaction to 19th century concerns about misogeny and racial purity.

  12. Ronald,

    Great post. Thank you for providing updated information on the study to readers. It is much appreciated.

    For further information regarding MON 810 and our position on the Austrian study, you can check out our For the Record page, it is linked from my name in this post.


    Kathleen Manning
    Monsanto Company

  13. hardworking busy H&R readers

    Ronald Bailey: Science Correspondent and comedian.

  14. “I think at some level they are embarrassed by the similarity of their reaction to 19th century concerns about misogeny and racial purity”

    here here
    GM is Miscegenation for plants

    and there really is nothing that’s as much fun as a bit of miscegenation

    free the plants

  15. What happens if I go up to a German girl and whisper “Nie mehr ohne” into her ear?

  16. Why would the Austrians care – they don’t seem to want children anyway. Aren’t they way below replacement rate already? But then they soon may be replaced by Eurabians who are concerned about fertility – for all their wives.

  17. Face it, folks. This is a tactic that the Greens have been using for at least 15 years: Cherry pick unreviewed data for the snippets that support your position and publish your own conclusions as a press release. After all, those responsible for the release are not the same folks responsible for the accuracy of the data. They pulled this nonsense with the Monarch butterfly and Starlink incidents, neither of which resulted in the disasters they predicted. But, as the saying goes, “you can’t unring the bell.”

  18. Ah good lord, are you all(not all but mostly) stupid or what?
    If GM-food can affect mice, do you think humans are immune? are we better? in molecular terms?
    once the birth rates of all humans go down(not as if that wasnt good for earth) you will see that the greatest danger to humans are humans themselves. We have long left the part of nature and balance. and we keep playing with the environment as if it was indestructible and would last forever.
    get the bigger picture. we are blindly killing ourselves.
    what holiness and untouchability lies in forbidding the direct manipulation of the human gene when we at the same time manipulate the genes of everything else..
    as if we werent affected by our environment and food…

  19. The only way to get rid of GMOs is for people to stop buying them. Products containing Corn, Canola, Cotton (seed oil), and Soy are the main ones in the US that we should all avoid, or buy organic, as long as they are being genetically modified here. And of course this includes products including ingredients derived from these crops like high-fructose corn syrup.

  20. With many new announcement about the wizard of oz movies in the news, you might want to consider starting to obtain Wizard of Oz book series either as collectible or investment at RareOzBooks.com.

  21. Hey, Don’t forget: WE have tremendous power here. STOP buying GMO’s! Tell your friends! You may be thinking millions of others will still support these companies, but remember: they only turn a fraction of their total income into profit. If we can change the minds of 5 to 10% of their market, we can bankrupt them. THAT is why they fight you so hard right from the start!
    Mary from Colorado

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