The analyzes performed on marketing GMOs before they are insufficient? This is the question posed by the study published Monday, December 19 in the journal Scientific Reports. This shows significant differences between a GM maize and its unmodified equivalent, which are not taken into account in the risk assessments carried out by the health authorities.
In fact, the authorization of GMOs is based on a presupposition: the “principle of substantial equivalence”. This principle, controversial, implies that if a product is considered substantially equivalent to the body from which it was made, no further investigation is necessary before placing it on the market. “It is generally considered that the GM maize and non-GM are similar, except for the modified gene,” says Robin Mesnage, molecular toxicology researcher and co-author of the study. GMOs are not so thoroughly tested before marketing, as it is customary to make for new drugs or new food additives. “The analyzes performed on GMOs to the state substantially equivalent are very limited and usually consist of nutritional analysis,” says Robin Mesnage.
The study, published by an international team of researchers, calls into question the use of this principle of equivalence in substance by showing that a GMO does not go down on the molecular scale the same composition as its Unchanged equivalent. To do this, the authors used two advanced techniques: proteomics and metabolomics. The first allows for mapping all the proteins that make up the corn; The second identifies the small molecules resulting from the metabolism of the plant (that is, the way it degrades the nutrients it uses).
The scientists conducted their study on a genetically modified maize – known as NK603, marketed by the firm Monsanto -, associated or not with Roundup, the herbicide to which it is tolerant – and its conventional equivalent. “In this study, researchers went much further than what has been done so far,” says Bernard Salles, director of food toxicology unit of the National Institute of Agronomic Research (INRA), which n Did not participate in the study. Indeed, the analytical methods used are not implemented by the industry food or state regulatory agencies to assess GM crops. “Our new study describes the composition of GM maize NK603 to a level hitherto unknown confirms Robin Mesnage. This analysis allowed us to measure 840 proteins and small molecules 314. “
And thanks to this in-depth analysis, the researchers found large differences in composition between GM corn and its unmodified counterpart. “Here we have many molecules – proteins, vitamins, antioxidants – found in different amounts between GM plant and non-GM says Robin Mesnage. And some of these molecules are known to be toxic or beneficial effects on health. “The results show for example that certain substances called polyamines – which the researchers write, are” according to the context protective or toxic “- can be between two and nearly three times more present in the GMO than its conventional counterpart. The analyzes carried out by the health authorities using the principle of equivalence in substance therefore do not take these differences into account.