The European Food Safety Authority (EFSA) is requesting public comment regarding its draft guidance for the risk assessment of nanoscience and nanotechnology applications in the food and feed chain until March 4, 2018. This draft guidance is an update to the 2011 guidance and takes into consideration the new scientific developments which provide new and updated information for nanomaterial exposure assessment and hazard characterization. The draft guidance also addresses in vivo/in vitro toxicological studies, advises how to conduct risk characterization and uncertainty analysis, and outlines a tiered framework for toxicological testing.