How does the public react when scientists disagree? Scientific consensus and risk communication

The way people perceive risks is an important element of risk communication, that has to be considered by media professionals and food safety authorities alike. Non-experts in risk assessment have to rely on the expertise of others. Therefore, the role of scientific consensus and trust in the judgement of experts seem to lie at the core of risk perception and successful risk communication with the general public. Yet, studies on the role of scientific consensus in perceiving risk are scarce. On the 19th of September, a study on long term toxicity of herbicide-tolerant, genetically modified maize NK603 diet in Sprague Dawley rats was published online by the journal of Food and Chemical Toxicology. The results, illustrated by pictures of malformed rat females quickly found their way into leading popular internet media and triggered a heated debate within the scientific community, among European food risk authorities, and anti-GMO campaigners. So far the majority of the scientific critics have agreed that Seralini et al’s study displayed some serious methodological flaws, while the first EFSA review of the study showed that Seralini et al.’s methods did not meet OECD standards. In our study we focus on public reactions to scientific controversy surrounding the study of Seralini’s team, using this example as a case study. Our aim is to link perceived risk from GM organisms with the role of scientific consensus in risk communication. We employed a mixed-method approach, combining thematic analysis with a survey. We have collected materials from web pages on English-speaking internet sites and launched a web-based survey to study the general public’s response to the GMO controversy. Our preliminary results indicate that the lack of scientific consensus is the main and very serious factor undermining trust both in food safety authorities and the scientific community in general. On the other hand, trust does not only apply to the information source, but to communication content as well. Many studies on risk perception show a very strong bias towards negative information occurring regardless of trust in the information source. The different tone of media reports in the U.S. and Europe indicate that initial attitudes towards GMO play a crucial role in risk communication. Finally, media also fine-tune their messages to readers’ reactions, reinforcing initial beliefs of the public. Scientific consensus appears to be a promising way to break this vicious circle.