The now famous study linking genetically modified corn to an increased rate of tumors in lab rat subjects has been officially retracted by the journal that published it. What does this mean, and why are the study’s findings in doubt?
The study, an investigation into the “Long term toxicity of a Roundup herbicide and a Roundup-tolerant genetically modified maize,” was published in in the journal Food and Chemical Toxicology in 2012.
As Care2 previously discussed, after studying 200 rats fed Monsanto’s glyphosate-resistant NK603 maize (corn) over a period of two years, researcher Gilles-Eric Seralini of the University of Cean, in France, and team said they found that the rats were at a significantly greater risk of developing tumors and fatal diseases. The study also found that when glyphosate, the herbicide used to cultivate GM corn, was added to the rat’s drinking water, the rats also developed a greater risk of fatal tumors and diseases.
Almost as soon as the study was published, with much media fanfare, concerns were raised on a number of fronts. For one, Gilles-Eric Seralini is a long time opponent of genetically modified foods. This doesn’t necessarily bias the findings but when teamed with a number of other factors did seem to make the study suspect. For instance, the number of rats used in the trial was very small for what was being tested, especially when considering that there was no control used to account for the type of rat used.
Editors of the publishing group Elsevier which carries Food and Chemical Toxicology, among them Editor-in-Chief Wallace Hayes, were soon flooded with letters of concern. An investigation into the study was started. It appears that earlier this year the research team behind the study was asked to make a retraction. They declined and stand by their findings. Nevertheless, the publishing group issued its own retraction at the end of November.
A summary of the findings appear below but you can find the full statement here.
1. No evidence of fraud or intentional misrepresentation of the data.
The statement makes it quite clear that the Editor-in-Chief, after an exhaustive review, found the researcher’s previous anti-GM food work played no part in biasing or misrepresenting the data of the study. The statement also notes that while the authors refused to retract the study themselves, they complied fully with information requests when they were made by the Editor-in-Chief and review team.
2. Concerns over the type of rats used and the number of test subjects are valid.
The statement relates that the peer review process had been aware of the low number of test subjects but had considered the work still valid. However, a more in-depth look at the research concludes that because of the low number of test subjects, the study cannot support a definite statement as to the role of NK603 or glyphosate and whether it increased mortality and tumor rates.
Furthermore, the statement specifically notes that the type of rat used in the study, known as the Sprague-Dawley rat, is known to have a higher incidence of tumors. Why this matters is that it means there is further doubt as to whether NKK603 or gylphosate is a danger or whether the higher rate of tumors among the rats was at least in part due to the species involved.
3. The study was inconclusive and should not have been published.
The Editor-in-Chief has concluded that based on these facts the results were inconclusive and, after further review, did not meet the so-called threshold for publication. As such, the study is now retracted.
Authors Say Study Retraction is Due to Monsanato Bias
The research team behind the study has said they find the retraction dubious, with co-author and physician Joel Spiroux de Vendomois quoted as saying “The magazine reviewed our paper more than any other,” and added that the retraction is “a public-health scandal.”
The researchers also charge that the study retraction may in part be due to the journal having (relatively) recently appointed biologist Richard Goodman. The scientist worked for Monsanto for seven years and is known to support GMOs. Goodman, however, has pointed out that he played no part in reviewing the study, saying, “Food and Chemical Toxicology asked me to become an associate editor in January 2013 because of my extensive experience in the area, and after I complained about the Seralini study. I am paid a small honorarium for handling manuscripts about biotechnology on a part-time basis, after hours. But I did not review the data in the Seralini study, nor did I have anything to do with the determination that the paper should be withdrawn from or retained by the journal.”
What Does the Retraction Mean?
Retraction means that the study now cannot be cited as any kind of proof or suggestion that GM corn may raise health concerns.
Further independent research will be needed in order to assess the claims made in this study. The problem for the general public who have no particular horse in this race is that it appears increasingly difficult to find researchers and wider peer review bodies that do not fall into either the pro or anti-GMO camps. This is a problem because, as we have seen, accusations of bias on both sides are clouding what is a very important public interest issue and are undermining public confidence in GM products.
Photo credit: Thinkstock.