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Séralini affair

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The Séralini affair involved the publication of a study in the journal Food and Chemical Toxicology on September 19, 2012 by a lab at the University of Caen led by Gilles-Eric Séralini, which purported to document that rats fed GM "Roundup Ready" maize got more cancer than controls, and that more of them died early. A health scare resulted, especially in Séralini's home country of France; for example, Le Nouvel Observateur covered it in a story called, "Yes, GMOs are poisons!". The study, after it was published, was criticized by many people, including Marion Nestle, who wrote, "It’s weirdly complicated and unclear on key issues: what the controls were fed, relative rates of tumors, why no dose relationship, what the mechanism might be. I can’t think of a biological reason why GMO corn should do this." Another critic was Australian plant biologist Mark Tester, who wrote, "The first thing that leaps to my mind is why has nothing emerged from epidemiological studies in the countries where so much GM has been in the food chain for so long? If the effects are as big as purported, and if the work really is relevant to 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!” Tester, when contacted by New Scientist, also said, "They show that old rats get tumours and die; that is all that can be concluded." In addition, David Gorski (among others) criticized the study on the basis that the researchers may have intentionally cherry-picked their own data, citing as evidence the statement in the study that "All data cannot be shown in one report, and the most relevant are described here," as well as the fact that "the Roundup and the GMO corn appeared to have the same detrimental effects." New Scientist also pointed this out, writing, "It is hard to imagine any way in which a herbicide could have identical toxic effects to a gene tweak that gives the maize a gene for an enzyme that actually destroys the herbicide."

Background

Gilles-Eric Séralini (born August 23, 1960) has been a professor of molecular biology since 1991 and is one of the leading scientific opponents of GMOs. He is president of the scientific board of the anti-GMO organization CRIIGEN. He started doing research in 1987, after he received his doctorate. His research originally focused on aromatase inhibitors, but starting in 2007 he began publishing anti-GMO research.

Criticism of the study

Confidentiality agreement

"...the research group did not allow reporters to seek outside comment on their paper before its publication in the peer-reviewed journal Food and Chemical Toxicology and presentation at a news conference in London." Many people criticized this practice because it prevented the other side of the story from being heard in news reports about the study; for example, David Gorski called it "cowardice and an unseemly attempt at spin," and Steven Novella wrote of the practice, "That’s more than suspicious – I think it’s unethical." Other critics of this practice included Cosmos Magazine's Elizabeth Finkel, who wrote, "...a clause barring the gathering of independent opinions is extraordinary. What it meant was that Séralini’s story, when it broke, got to prance unfettered in the media limelight before second opinions could dull its shine. By the time the storm of criticism blew in, the media limelight had moved on."

Strain of rat used

Séralini faced criticism for using Sprague-Dawley rats for a 2-year study (they are normally used for 3-month studies) because they have a high tendency to develop cancer over their 2-year lifespan, meaning that, as biologist Andrew Kniss pointed out, "...there is a pretty good chance the percentage of 10 rats developing tumors could be MUCH different than the population mean of 72%. This is because there is a greater chance that our small sample of 10 will not be representative of the larger population."

This argument has been refuted on the GMOSeralini.org website.

Number of rats per experiment

17 letters to the editor were published in response to this study; all were harshly critical of it. One was written by the president of the SFPT (i.e. French Society of Toxicologic Pathology), who wrote, "...from a statistical perspective, this long term study is largely underpowered with only 10 animals per sex per group, while the accepted guidelines recommend using groups of at least 50 animals per sex per group, and define strict survival rate criteria that the groups must respect for the results to be considered valid." Séralini's response was reported by the Guardian in a sympathetic article about the study: namely, that "...six is the OECD recommended protocol for GM food safety toxicology studies and he had based his study on the toxicity part of OECD protocol no. 453. This states that for a cancer trial you need a minimum of 50 animals of each sex per test group but for a toxicity trial a minimum of 10 per sex suffices. Monsanto used 20 rats of each sex per group in its feeding trials but only analysed 10, the same number as Séralini." Another problem was highlighted by Anthony Trevawas, who wrote that the study's results are "of no value" because there were only 20 controls and 80 treated rats.

This argument has been refuted on the GMOSeralini website.

Lack of data on confounding factors

Tom Sanders, who works at Kings College London, wrote that since Sprague-Dawley rats are susceptible to mammary tumors when food intake is not restricted, data should have been provided about how much food the rats were fed (as well as the presence of fungus in the feed, another confounder).

Statistical analysis

Sanders wrote of this study, "The statistical methods are unconventional ... and it would appear the authors have gone on a statistical fishing trip." In New Scientist, Debora Mackenzie called the analysis "complicated and unconventional".

Lack of a linear dose-response relationship

As reported by New Scientist's Debora Mackenzie, "Even the smallest dose that the team applied resulted in alleged effects on the rats. That is sometimes seen with other toxic agents. The team suggests that the effect kicks in at some very low dose, hits its maximum extent immediately, and stays the same at any higher dose. But it could more simply mean the GM maize and the herbicide had no measured effect, and that is why the dose made no difference." Furthermore, as Tim Carman of the Washington Post put it, "the rats that consumed a diet with higher percentages of GM corn apparently did not get as sick as those with lower doses." In his "answers to critics" paper in FCT, Séralini wrote, "...one of the criteria for biological relevance employed by Monsanto and other critics of our study is the linearity or lack thereof in response to the dose. Such a dose–response relationship cannot be claimed from a trial using only 2 doses of test material as employed in the initial NK603 assessment (Hammond et al., 2004). We therefore find it surprising that the relevance of Monsanto’s and the agencies’ conclusion of safety was not challenged due to such protocol insufficiencies."

Conflict of Interest

The aforementioned letter to the editor, written by the president of the SFPT, pointed out, "Regarding the statement that “The authors declare that there are no conflicts of interest”, we respectfully disagree: Pr Gilles-Eric Séralini being President of the Scientific Board of the CRIIGEN, and the CRIIGEN having been a “major support” of the study, it seems to us that this should have been disclosed." Similarly, Phys.Org noted that "his research was funded in part by an alliance comprising anti-GM campaigners and supermarket chains that have invested heavily in organic food. This was also highlighted by the Guardian, which reported Séralini's response: namely, that studies in support of GM food are usually funded by "corporates or by pro-biotech institutions."

Séralini's point that studies in support of GM food are usually funded by "corporates or by pro-biotech institutions" is supported by two comprehensive peer-reviewed reviews of the scientific literature. These reviews found that studies concluding GMOs are safe are more likely to be funded by biotech companies or their associates, whereas independent studies are more likely to find that GMOs are risky.

Why no pictures of control rats?

Maurice Moloney, among others, went on record wondering why there were so many pictures in the study, and in sympathetic news reports about it, of treated rats with horrific tumors, but no pictures of the rats in the control group.

But it's just one study!

As Jon Entine put it at Forbes, "Seralini's research is anomalous. Previous peer-reviewed rat feeding studies using the same products (NK603 and Roundup) have not found any negative food safety impacts. The Japanese Department of Environmental Health and Toxicology released a 52-week feeding study of GM soybeans in 2007, finding “no apparent adverse effect in rats.” Earlier this year, a team of scientists at the University of Nottingham School of Biosciences released a review of 12 long-term studies (up to two years) and 12 multi-generational studies (up to 5 generations) of GM foods, concluding there is no evidence of health hazards." Andrew Revkin dubbed it another instance of "single-study syndrome", and contended that the study was in support of an "agenda".

Major risk-assessing bodies weigh in

German Federal Institute for Risk Assessment VP Reiner Wittkowski said in a statement, ""The study shows both shortcomings in study design and in the presentation of the collected data. This means that the conclusions drawn by the authors are not supported by the available data." Similar conclusions were reached by the French Higher Biotechnologies Council and the National Agency for Food Safety, the Vlaams Instituut voor Biotechnologie, the Technical University of Denmark, Food Standards Australia New Zealand, Brazilian National Technical Commission on Biosafety, and the European Food Safety Authority.

Calls for retraction

The aforementioned Mark Tester wrote a letter to the editor of FCT calling for the paper to be retracted. In addition, the European Federation of Biotechnology also called for the paper to be retracted, calling its publication a "dangerous failure of the peer-review system."

Release the data!

Henry I. Miller, writing for Forbes, wrote of the study that "the investigators have refused to release all the data from the experiment, which constitutes scientific misconduct." Séralini responded by saying, "...that he won’t make any data available to the EFSA and the BfR until the EFSA makes public all the data under-pinning its 2003 approval of NK603 maize for human consumption and animal feed." In his answers to critics, Séralini et al. wrote, "we will release our raw data if the regulatory agencies that have taken industry data into account in their approval of their products also release the data pertinent for environmental and health risk assessments, in particular their longest toxicological tests on mammals, as we have indicated in our correspondence with EFSA. As a first step to this end, we have communicated the raw data underlying the data presented in Figs. 1 and 2 to the French food safety agency (ANSES), and answered their questions on experimental design and results, including analysis of food composition and mycotoxin content, etc." The EFSA has done so.

Alternative view

An alternative view of the study to the one detailed above is given by the public information website gmoseralini.org, written by citizens and scientists who were concerned that important findings that directly impact public health were being buried. The website states, "The research conducted by Séralini’s team has serious implications for public health and the environment and should be addressed rationally and on scientific grounds. We aim to address and correct many of the misleading statements that have been made about the research of Séralini’s team." The website answers the criticisms leveled at the study in fully referenced text, and hosts scores of letters from scientists supporting Séralini's study. In addition, it reveals the conflicts of interest of Séralini's critics, which often went undisclosed.

The undisclosed conflicts of interest of many of Séralini's critics are detailed in the article, "Smelling a corporate rat", by Jonathan Matthews for Spinwatch.

References

  1. Séralini GE; et al. (2012). "Long-term toxicity of a Roundup herbicide and a Roundup-tolerant genetically modified maize". Food and Chemical Toxicology. 50 (11): 4221–4231. doi:10.1016/j.fct.2012.08.005. PMID 22999595. {{cite journal}}: Explicit use of et al. in: |author= (help); Unknown parameter |month= ignored (help)
  2. Séralini GE; et al. (2007). "New Analysis of a Rat Feeding Study with a Genetically Modified Maize Reveals Signs of Hepatorenal Toxicity". Arch. Environ. Contam. Toxicol. 52 (4): 596–602. doi:10.1007/s00244-006-0149-5. PMID 17356802. {{cite journal}}: Explicit use of et al. in: |author= (help); Unknown parameter |month= ignored (help)
  3. "The GM Corn Rat Study". Neurologica Blog. Retrieved 8 May 2013.
  4. GM Corn and Cancer: the Seralini Affair
  5. GMOSeralini (2013) Criticism: Séralini used a type of rat naturally prone to tumours
  6. GMOSeralini (2013) Criticism: Séralini used too few animals to draw any conclusions
  7. Letter to the editor of FCT
  8. GMOSeralini (2013) Criticism: Séralini used too few animals to draw any conclusions
  9. "UPDATE 3-Study on Monsanto GM corn concerns draws scepticism". Reuters.com. Retrieved 8 May 2013.
  10. ^ Séralini GE; et al. (2013). "Answers to critics: Why there is a long term toxicity due to a Roundup-tolerant genetically modified maize and to a Roundup herbicide". Food and Chemical Toxicology. 53: 476–483. doi:10.1016/j.fct.2012.11.007. PMID 23146697. {{cite journal}}: Explicit use of et al. in: |author= (help); Unknown parameter |month= ignored (help)
  11. "Six French academies dismiss study linking GM corn to cancer (Update 2)". Phys.org.
  12. "Study linking GM maize to cancer must be taken seriously by regulators". The Guardian. Retrieved 8 May 2013.
  13. Diels, J., et al. (2011). "Association of financial or professional conflict of interest to research outcomes on health risks or nutritional assessment studies of genetically modified products." Food Policy 36: 197–203.
  14. Domingo, J. L. and J. G. Bordonaba (2011). "A literature review on the safety assessment of genetically modified plants." Environ Int 37: 734–742.
  15. French GM-fed rat study triggers furore
  16. "Does the Seralini Corn Study Fiasco Mark a Turning Point in the Debate Over GM Food?". Forbes.com. Retrieved 11 May 2013.
  17. Single-Study Syndrome and the G.M.O. Food Fight
  18. ^
  19. "Scientists Smell A Rat In Fraudulent Genetic Engineering Study".
  20. GMOSeralini (2013), About Us, accessed 13 May 2013
  21. GMOSeralini (2013), GMOSeralini, accessed 13 May 2013
  22. Matthews J (2012), Smelling a corporate rat, Spinwatch, 11 Dec, accessed 13 May 2013
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