French opposition to GMOs seems set to increase. Credit: REUTERS/Regis Duvignau

A scandal—cried French newspaper Le nouvel Observateur—following publication of a paper by Gilles-Eric Séralini from the University of Caen, in France, on a long-term study of the toxicity of GM maize. The study's online publication on September 19 by Food and Chemical Toxicology prompted a media frenzy. The study made a bombshell claim, completely unprecedented in the literature: rats fed for two years on Monsanto's NK603 corn expressing 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), cultivated with or without Roundup, and Roundup alone, develop a range of tumors. The authors claimed that the disruption of biosynthetic pathways that may result from overexpression of EPSPS in the GM maize can give rise to pathologies.

The study, said to have cost €3 ($3.9) million, was dismissed as scientifically unsound by numerous scientists with or without ties to the agbiotech industry. Both the German Federal Institute for Risk Assessment (BfR) and the European Food Safety Authority (EFSA) lamented inadequate experimental design, poor analysis and data reporting. Writing on behalf of the European Federation of Biotechnology, biotech pioneer Marc Van Montagu comments on the study. “This paper represents a dangerous case of failure of the peer-review system.” Van Montagu also lambasts the communication strategy of the authors. The publication was timed to coincide with a book on the experiment and a film to be broadcast on public television and in cinemas.Most unusually, an association representing Séralini offered interested journalists a confidentiality agreement to get early access to the paper that prevented signatories from approaching third-party researchers for comment, with a penalty of several million euros to be levied if the contract were breached. As a consequence, initial media coverage was almost ubiquitously noncritical.

Controversy soon followed when funding ties with several supermarket chains promoting non-GM positions were revealed; Séralini's decision not to provide EFSA with additional unpublished data also did not help. “If the intention was to 'manage' the news, it wasn't managed very well,” says Jonathan Amos from the BBC, which did not sign the confidentiality agreement. Despite the paper's flaws, it seems likely that the initial coverage will negatively sway public and political opinion in France, where it seems to have hardened the socialist government's already unfriendly stance toward GM organisms. Before the French Agency for Food, Environmental and Occupational Health & Safety (Anses) could deliver its opinion (expected by the end of October), the agriculture minister Stéphane Le Foll stated that long-term feeding studies should become mandatory for GM food crops, even if Séralini's work is debunked.