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In Depth: Journal Retracts Independent Study Linking Monsanto GMO Corn to Cancer in Rats

(Image: JR / TO; Adapted: Giandomenico Pozzi, Tatiana Bulyonkova)

Last September, an alarming study rocketed through media and unleashed a storm of controversy. French researchers appeared to have uncovered a link between a Monsanto genetically engineered corn variety and cancer in lab rats. Now, more than a year later, a respected American scientific journal has taken a black eye and retracted the study, reigniting a global debate that raises serious questions about the media’s coverage of biotechnology research and the deep divisions between industry-backed researchers and independent scientists.

The two-year study, conducted by a team lead by French biotech critic Gilles-Eric Séralini of the University of Caen, found that groups of lab rats fed a lifetime diet of either Monsanto’s NK603 corn (NK603 is treated with Roundup herbicide) or exposed to varying levels of Roundup herbicide in drinking water died earlier and had higher rates of tumors and organ damage than controls. NK603 is a genetically modified organism, or GMO, that is bioengineered to tolerate Roundup.

On November 28, the Journal of Food and Chemical Toxicology officially retracted the study, effectively removing Séralini’s findings from the realm of accepted science. In a statement, chief editor, A. Wallace Hayes, echoed critiques from scientists around the world who pointed out that Séralini did not experiment on enough rats to support his explosive cancer claims, and the Sprague Dawley lab rats used in the study are prone to developing tumors if allowed to live long enough.

Independent scientists, however, say the Sprague Dawley breed is an industry standard for toxicity research, and while the Séralini study is not perfect, there is no legitimate reason to remove it from scientific debate. Séralini and his team refused an offer from Hayes to voluntarily retract the study and continue to publically defend their findings.

“Inconclusive,” But “Not Incorrect “

Hayes said that he “found no evidence of fraud or intentional misrepresentation of the data,” but after reviewing Séralini’s raw data, determined the results were “not incorrect,” but “inconclusive,” and therefore not suitable for publication.

Séralini’s supporters were quick to point out that Hayes’ journal is a member of the Committee on Publication Ethics and guidelines issued by the committee state that editors should only consider retracting a study if there is evidence of plagiarism, unethical research, or unreliable findings based on misconduct or honest error. Simply being “inconclusive” does not make the cut.

“You don’t get papers retracted for this,” said Michael Hansen, a biotechnology analyst for Consumers Union, which publishes Consumer Reports. Hansen added that plenty of published scientific studies are inconclusive, and the retraction borders on “scientific censorship.”

Here’s where the Séralini Affair gets tricky. The French team never definitively concluded that Monsanto products caused bulging tumors in the rats; his team simply reported the high tumor rates along with its analysis of kidney and organ damage. The project was a long-term toxicity study model of a 90-day Monsanto safety study, which also used Sprague Dawley rats, not a carcinogenicity study, which would have required a larger number of lab rats. In response to heaping criticism, Séralini’s team members said they had simply pointed out the alarming tumor data and called for further research on the safety of GMO corn.

While ANSES, the French food safety authority, joined other European food regulators and scientific academies in dismissing the study, the French officials also called attention to the “originality” and agreed that more research should be done on the long-term health effects of consuming GMO crops and the pesticides associated with them. The European Commission has also considered funding a long-term feeding study on Monsanto corn.

Séralini did hype the cancer findings in the media while simultaneously releasing a book on his GMO research. The study was initially released to journalists under a heavily criticized embargo and included grotesque images of rats with giant tumors. The breaking news generated alarming headlines around the world, setting off a general panic among politicians and regulators in several countries where GMOs are unpopular. France launched an investigation into the findings, and Russia declared a temporary ban on NK603 while food safety officials reviewed the study.

Amid media hype, public discussion of the study deteriorated into a grinding and spin-heavy information war. Pro-business pundits and industry-funded front groups went on the offensive to discredit the study and called for a retraction. Independent scientists and biotech critics attempted to expose Séralini’s detractors as industry shills who stand ready to trash any research that raises concerns about GMOs. Proponents of a failed GMO food labeling ballot initiative in California touted the study as alarming evidence that consumers cannot be sure that GMO groceries are safe. Writers Keith Kloor and Jon Entine attacked progressive news outlets for lending legitimacy to the study and accused GMO skeptics of being the left-wing version of climate-change deniers.

The retraction announcement further fanned the flames., which initially published several articles attacking the study, celebrated the retraction. Biotech critics attempted to spark a scandal by pointing out that Richard Goodman, a food allergy expert and professor at the University of Nebraska, had been appointed an associate biotechnology editor of Food and Chemical Toxicology a few months after the study was published. Goodman is a former Monsanto employee, but he has denied being involved in the decision to retract the Séralini study.

In an email to Truthout, Goodman said that he left Monsanto in 2004 and continued his career as an independent research professor, but “people will connect the dots that they perceive to be true, no matter what I say.

“If you knew me personally, you would know that people do not tell me what to write or say (or if they do try, I will not listen),” Goodman wrote. “I listen to the scientific facts, and I think as a scientist. I judge based on science.”

A Double Standard?

In an official response to the retraction, the Séralini team said its research was a long-term toxicology study modeled from short-term industry studies like those funded by Monsanto to gain regulatory approvals in Europe, and its critics are holding the independent science to a “double standard.” If the journal throws out Séralini’s study, they argued, then a 90-day Monsanto study on NK603, which used the same breed of rats, should be thrown out as well.

“It is true that there’s clearly a double standard here,” Hansen told Truthout. “Any study that shows no problem with [GMOs], as soon as its published, it’s just accepted, it’s not looked with detail . . . but any study that shows any problems, it gets ripped apart and ran through with a fine-tooth comb.”

Hansen says the Food and Chemical Toxicology has published several long-term studies that determined GMOs did not harm the same Sprague Dawley rats Séralini was criticized for using, but those have not been retracted. Hansen also points to a recent European review of Séralini’s study and two other feeding studies on NK603, including the Monsanto study that Séralini had based his own research on. The comparative analysis found that all three studies failed to satisfy European Food Safety Authority criteria, but the regulatory body only dismissed the Séralini study, revealing “critical double standards.”

So what’s left of the Séralini Affair? It’s now clear that the initial rat tumor uproar was based on a well-publicized, but inconclusive, toxicology study that raised more questions than it answered before being removed from the scientific cannon under sketchy ethical circumstances. But Séralini has succeeded in pointing out flaws in the industry’s own GMO safety testing and inspired further research on the subject, at least in Europe.

Whether he intended to or not, Séralini also taught the media some important lessons about covering biotechnology issues in a world where the voices of independent scientists compete with powerful corporations claiming to own the right to define legitimate science. It seems the public relations teams for the biotech and agrichemical industry may not the only ones who know how to play the game.

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