Le face-à-face OGM - agriculture biologique en Europe : entre réglementation et recommandation

The European Regulation 834/2007, responsible for the definition of the European Organic Label since 2009, allows a non-intentional presence of authorised GMOs limited to the threshold of 0.9 % in organic production. Such a threshold, when strictly positive, allows organic producers to keep the organic label in case of a small GM contamination. However, it may bring discredit on the organic agriculture which can no more be understood as "GMO-free". The European Commission in its recommendation 2003/556/CE proposes that GM producers should bear the cost of the measures decided to limit the dissemination of the GM gene - the so-called "newcomer principle". European countries are however free to adopt such a principle and can proceed differently. This article presents an economic analysis of the determination of the optimal GMO threshold maximizing society's wellbeing when the newcomer principle is implemented and when it is not. This optimal GMO threshold in both cases is decided by an impartial regulator facing heterogeneous consumers, and is intended to ensure the coexistence between GM and organic agricultures, taking into account of the potential discredit it implies on organic agriculture and the flexibility it allows for the preservation of the organic label. We first establish the conditions for coexistence. We then show that i) the GMO threshold can be different from zero if the organic producers bear the cost of the coexistence measures and ii) the GMO threshold should be zero under the newcomer principle.