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by Lucy Sharratt, CBAN, Common Ground, August 2014.

A French study on the safety of a genetically modified (GM, also called genetically engineered) corn has just been republished. This seemingly ordinary event is globally significant. The study and the public fight over it exposes an ugly and dangerous reality in the regulation of GM foods across the world: The GM foods we are eating have not been subjected to long-term animal feeding trials.

The team of French scientists, led by Caen University molecular biologist Giles-Éric Séralini, conducted a two-year animal feeding trial on GM corn. It was published in September 2012 in the journal Food and Chemical Toxicology, but was retracted a year later after a coordinated industry backlash that included the appointment of a former Monsanto employee to the journal’s editorial board.

The retraction itself was unprecedented because of the reasons given (the results were inconclusive) and the misrepresentation of the study in the journal’s rationale (that the study made claims about cancer when “cancer” is not even mentioned in the study).

The paper is now published in the online journal Environmental Sciences Europe. The journal’s editor, Winfried Schröder, said, “We want to enable a rational discussion about the study.”

Back in 2007, Professor Séralini and his team had already analyzed Monsanto’s data on a different (insect resistant) GM corn, MON863. A German court ruling had provided the team with the raw data, over Monsanto’s objections, and the team concluded the data actually shows signs of liver and kidney toxicity. They stressed the need for studies beyond the industry standard of 90 days, but Monsanto did not take up the challenge.

To test the question of chronic health impacts, Séralini’s team conducted a feeding trial of GM corn NK603 over the full two-year lifespan of rats. NK603 is a GM trait that creates GM “Roundup Ready” corn, which is tolerant to Monsanto’s brand-name herbicide formulation called “Roundup” (fields can be sprayed with Roundup and the weeds die while the GM corn lives). The rats were fed three different diets: The GM corn alone, the GM corn grown with Roundup (with Roundup residues, because this is how the corn is grown) and Roundup alone.

The team summarized the results in their June 2014 press release: “…Roundup causes severe liver and kidney deficiencies and hormonal disturbances, such as breast tumours, at low environmentally relevant levels. Similar effects were observed from the chronic consumption of Roundup-tolerant GM maize [corn]. This is due to residues of Roundup and to the specific genetic modification of this maize. The formulations of Roundup, as well as Roundup-tolerant GMOs, should therefore be considered endocrine (hormone) disruptors and should be re-evaluated for safety by the health authorities.” The first tumours were observed one month after Monsanto’s 90-day test ended and peaked at 18 months.

The GM trait NK603 was approved in Canada in 2001, three years before Monsanto even published its short, now challenged, 90-day feeding trial. For over a decade, corn with this GM trait has been used for animal feed and in processed food ingredients in Canada, but Monsanto also recently put NK603 into GM sweet corn (2012). We know, from tests done by the Canadian Biotechnology Action Network, that GM sweet corn is in some grocery stores, farmers markets and roadside stands across the country.

Recommended reading

GMO Myths and Truths, Second Edition. May 2014. Earth Open Source,