Paper Title
Nanotechnologies: What Means a Benefits/Risks Approach in the “Imperative of Precaution” Context?

This paper addresses issues raised by the development of nanotechnology. Although the expansion of the latter is not as fast as supposed, these new technologies have brought public controversies that are to be considered. In this research, we show that a condition for the development of medical nanotechnology is to revisit the concept of benefit-risk balance, too often considered from a technical point of view. To the extent that the risks are uncertain without any overall conclusions being drawn, it must be determined whether the applications offer benefits or not, in order to reduce the scope of nanomaterials and applications to be assessed. However, the determination of a benefit cannot be reduced to the physicochemical properties of the materials. It is a social process that combines efficiency and validity of applications. The determination of validity implies cooperation not only between the materials sciences and the social sciences, but also between academic research and public representations such as associations, be they environmental, patient or consumer ones, for example. This cooperation must take place upstream academic research, thus before any development of applications. Index Terms - Nanotechnologies, precaution, medical device, benefits