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Major Study: Monsanto GMO Corn Can Cause Damage to Liver and Kidneys, and Severe Hormonal Disruption

Key study has passed through three peer reviews.

Photo Credit: meandar


A scientific study that identified serious health impacts on rats fed on 'Roundup ready' GMO maize has been republished following its controversial retraction under strong commercial pressure. Now regulators must respond and review GMO and agro-chemical licenses, and licensing procedures.

A highly controversial paper by Prof Gilles-Eric Séralini and colleagues has been republished after a stringent peer review process.

The chronic toxicity study examines the health impacts on rats of eating  a commercialized genetically modified (GM) maize, Monsanto's NK603 glyphosate-based herbicide Roundup.

The original study, published in Food and Chemical Toxicology (FCT) in September 2012, found severe liver and kidney damage and hormonal disturbances in rats fed the GM maize and low levels of Roundup that are below those permitted in drinking water in the EU.

However it was retracted by the editor-in-chief of the Journal in November 2013 after a sustained campaign of criticism and defamation by pro-GMO scientists.

Toxic effects were found from the GM maize tested alone, as well as from Roundup tested alone and together with the maize. Additional unexpected findings were higher rates of large tumours and mortality in most treatment groups.

Criticisms addressed in the new version

Now the study has been republished by Environmental Sciences Europe. The republished version contains extra material addressing criticisms of the original publication.

The raw data underlying the study's findings are also published - unlike the raw data for the industry studies that underlie regulatory approvals of Roundup, which are kept secret. However, the new paper presents the same results as before and the conclusions are unchanged.

The republication restores the study to the peer-reviewed literature so that it can be consulted and built upon by other scientists.

The republished study is accompanied by a separate commentary by Prof Séralini's team (also published on The Ecologist) describing the lobbying efforts of GMO crop supporters to force the editor of FCT to retract the original publication.

The authors explain that the retraction was "a historic example of conflicts of interest in the scientific assessments of products commercialized worldwide."

"We also show that the decision to retract cannot be rationalized on any discernible scientific or ethical grounds. Censorship of research into health risks undermines the value and the credibility of science; thus, we republish our paper."

Paper subjected to extraordinary scrutiny and peer review

Claire Robinson, editor of, commented: "This study has now successfully passed no less than three rounds of rigorous peer review."

First the paper was peer reviewed for its initial publication in Food and Chemical Toxicology, and according to the authors it passed with only minor revisions.

The second review involved a non-transparent examination of Prof Séralini's raw data by a secret panel of unnamed persons organized by the editor-in-chief of FCT, A. Wallace Hayes, in response to criticisms of the study by pro-GMO scientists.

In a letter to Prof Séralini, Hayes admitted that the anonymous reviewers found nothing incorrect about the results, but argued that the tumour and mortality observations in the paper were "inconclusive", and this justified his decision to retract the study:

"A more in-depth look at the raw data revealed that no definitive conclusions can be reached with this small sample size regarding the role of either NK603 or glyphosate in regards to overall mortality or tumor incidence. Given the known high incidence of tumors in the Sprague-Dawley rat, normal variability cannot be excluded as the cause of the higher mortality and incidence observed in the treated groups."

"The rationale given for the retraction was widely criticized by scientists as an act of censorship and a bow to the interests of the GMO industry", says Robinson.

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