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GMOs: EFSA dismisses Séralini's claims about GM-maize



GMOs: EFSA dismisses Séralini's claims about GM-maize

EU Regulatory Bulletin contents


The Séralini et al paper

In September 2012, the scientific journal Food and Chemical Toxicology published a research paper, prepared by molecular biologist Gilles-Eric Séralini, which raised concerns about the potential toxicity of NK603 maize and a herbicide containing glyphosate following conclusions that they induced severe adverse health effects in rats. (See our previous Bulletin contribution)

NK603 maize has been genetically modified in such a way as to be resistant to glyphosate, the active ingredient in Monsanto's pesticide product "Round-up" which, following certain safety evaluations, was authorised to be placed on the EU market pursuant to EU Directive 2001/18/EC.

The Séralini et al paper was heavily criticised by many industry stakeholders who consider the study lacks any scientific credibility and who believe that Séralini, a widely known opponent of GMOs, was merely manipulating public opinion by spreading unsubstantiated concerns. 

Nevertheless, Séralini's study prompted the European Commission to issue a formal request to EFSA to carry out a scientific review of the paper, to consider assessments of it conducted by Member States and to obtain clarifications from the authors, in order to determine whether EFSA's previous safety assessments of NK603 should be reconsidered.

EFSA's findings

On 28 November, following a preliminary assessment of the Séralini et al paper which cast doubt over the study, EFSA delivered its final evaluation highlighting a number of inadequacies in the design, analysis and reporting of it.  The study was found to have unclear objectives, insufficient detail about the feed and treatment formulations, insufficient detail about the statistical methods employed during the study, and an insufficiently low number of rats used in each treatment group.

During the course of the evaluation process, EFSA requested additional information from the authors to help provide some clarity, but these requests were unsuccessful and many queries remain outstanding.  On 9 November Séralini et al published a general statement in response to the numerous criticisms made of their study, within which is an acknowledgement that their study was based on an inadequate sample size of rats.  This acknowledgement, which is wholly inconsistent with the findings of their study, demonstrates that valid conclusions as to long-term carcinogenicity and mortality cannot be drawn from it. 

This, and the weaknesses identified by EFSA in its assessment led to the conclusion that there can be no sufficient scientific basis upon which to substantiate concerns about the toxicity of NK603 and any links it has to adverse health effects in rats.

EU Member State support

In addition to its own assessment, EFSA's was also required to take into consideration the independent assessments of the study made by Member States.  The assessments made by the relevant authorities in Belgium, Denmark, France, Germany, Italy and the Netherlands each revealed similar conclusions; namely that the study was inadequately designed, analysed and reported, and that it is of insufficient scientific quality for safety assessments.

EFSA's work was led by Per Bergman who confirmed that, in addition, many national organisations were independently mandated by Member States to assess the study, and there was an overwhelming consensus that the conclusions it reached were not supported by the data published in the report.

As such, the evidence gathered from the evaluation does not warrant any re-examination by EFSA of its previous safety evaluations of NK603 maize, nor does it have any impact on EFSA's ongoing re-evaluation of glyphosate.

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