Have you reviewed the study showing that GMOs caused cancer in lab rats?

Expert response from Alan McHughen

CE Biotechnology Specialist and Geneticist

Wednesday, 11/09/2013 16:19

The pictures from that study conducted by Gilles-Eric Séralini are frightening—and made for sensationalistic media coverage.  However, when teams of scientists from around the world looked at the study carefully, they found that the conclusions drawn by Séralini were not credible and that the study itself was seriously flawed and provided no new grounds for concern about GM food. 

The paper was criticized by public scientific and medical societies worldwide for its faulty experimental design, statistical analysis, interpretation and presentation of results. Problems included the well-known fact that the strain of rats used in the study (Sprague-Dawley) are prone to develop tumors at around age two regardless of their diet; Séralini attributed the tumors to the GM corn rations, but he could as easily have shown pictures of rats fed no GM corn but still full of tumors. Séralini’s data analysis was also unusual; the German risk assessment agency found it “impossible to comprehend.”  At the request of the European Commission, the European Food Safety Authority (EFSA) reviewed Séralini’s  study and released an opinion, which it summarized as follows:

“EFSA’s final review reaffirmed its initial findings that the authors’ conclusions cannot be regarded as scientifically sound because of inadequacies in the design, reporting and analysis of the study as outlined in the paper. It is not possible, therefore, to draw valid conclusions about the occurrence of tumors in the rats tested.”  (Frequently Asked Questions on review of Séralini et al. (2012) study)

EFSA also released a compendium of reports from agencies of EU Member States and scientific bodies that reviewed and rejected the Séralini paper.  These included reports from:

• Belgium: BAC (Biosafety Advisory Council);
• Germany: BVL (The Federal Office of Consumer Protection and Food Safety) and BfR (The Federal Institute for Risk Assessment);
• Denmark: DTU (The National Food Institute)
• France: ANSES (French Agency for Food, Environmental and Occupational Health & Safety);
• France: HCB (High Council For Biotechnology);
• Italy: ISS (Istituto Superiore di Sanità ) (National Institute of Health) & IZSLT (Istituto Zooprofilattico Sperimentale delle Regioni Lazio e Toscana);
• Netherlands: NVWA (Nederlandese Voedsel-en Warenautoriteit) (Dutch Food and Consumer Product Safety Authority).

All these agencies were extremely critical of the Séralini project and stated that it provided no new grounds for concern about the alleged tumor-causing properties of GM corn.  The EFSA final review and annex with the national reviews may be accessed here.

Numerous independent scientists wrote letters of rebuttal and protest to the journal Food and Chemical Toxicology.  These may be accessed here.