EFSA Reviews Study on GM Maize, Herbicide Toxicity
4 October 2012: The European Food Safety Agency (EFSA) has published an initial review of a recent study (Seraldini et al. 2012) that raises concerns about the potential toxicity of genetically modified (GM) maize and of a herbicide containing glyphosate. The EFSA review concludes that the quality of the study is insufficient to be considered for risk assessment.
According to the review, the conclusions of the study cannot be considered scientifically sound because of the use of inadequate design, analysis and reporting. In line with this review, EFSA does not see a need to re-examine its safety assessment of the concerned GM maize variety, nor to consider the findings in its ongoing assessment of glyphosate.
The study, titled "long-term toxicity of a Roundup herbicide and a Roundup-tolerant GM maize," was published in the peer-reviewed journal Food and Chemical Toxicology. The authors found that rats fed with GM maize tolerant to glyphosate (known as Roundup), cultivated with or without Roundup, and Roundup alone tended to die earlier than rats fed on a standard diet, because of tumors and other health defects.
The European Commission requested EFSA to review the study and assess its validity for risk assessment. The main findings of the review include: use of a strain of rats that is prone to developing tumors, which influences the rate of tumors observed; use of an insufficient number of control groups; lack of compliance with international recognized standard methods (protocols) or guidelines published by the Organization for Economic Co-operation and Development (OECD); lack of information on the composition of the food fed to rats, their intake during the study period and therefore insufficient information on the rat's exposure to glyphosate; lack of application of commonly-used statistical analysis methods; and lack of reporting on important data such as drop-outs and estimation of unbiased treatment effects.
EFSA is inviting the authors to respond to these findings and submit any missing data in the name of openness and transparency. [EFSA Press Release] [EFSA review of the study Seraldini et al. 2012] [Letter to Prof. Seraldini]