On March 5, 2009, the European Food Safety Authority (EFSA) published a document entitled The Potential Risks Arising from Nanoscience and Nanotechnologies on Food and Feed Safety, which provides its scientific opinion on the potential risks arising from nanoscience and nanotechnologies on food and feed safety. EFSA’s Scientific Committee (SC) concluded that established international approaches to risk assessment can also be applied to engineered nanomaterials (ENM). The SC also concluded that a case-by-case approach would be necessary and that, in practice, current data limitations and a lack of validated test methodologies could make risk assessment of specific nano products very difficult and subject to a high degree of uncertainty. The opinion focuses on the use of nanotechnologies, particularly ENMs, in the food and feed chain. It elaborates on approaches and methodologies available for risk assessment of these very small particles but does not address any specific applications of particular ENMs.