Legal aspects of the risks raised by nanotechnologies in the field of medicine.

The major breakthroughs achieved in nanotechnologies open new avenues in the field of healthcare--aid to diagnosis, upgrading medical treatment efficacy, development of regenerative medicine--but they are also associated with risks, hence the increasing need of legislation. So far very little research work has been conducted on this technology whose applications are still limited and whose potential hazards are not yet clearly apprehended. The more and more frequent uses of nanoparticles in medical imaging and in current research projects dealing with tissue engineering or RFID raises the following question: is the current legislative framework relevant in light of the specificities of nano-objects? The challenge is twofold: the legal approach must encompass the nanometric element itself as a "legal object" but it must include the use of nanotechnologies and their final aims. There is still some degree of uncertainty concerning the innocuity of nanoparticles so that the use of nanoelements in aid to medical diagnosis and in clinical trials must take into account and anticipate the potential harmful effects on patients and on biomedical research teams. But due to the fact that a clear understanding of nanoparticles as specific objects with new features is still missing, the existing regulations on chemical substances, medicinal products, medical devices or cosmetics do not seem to be appropriate. So considering nanoparticles as "singular" legal objects is a prerequisite requiring an approach based on the precautionary principle. Misusing nanotechnologies in the medical field is also a cause for great concern. Threats on individual freedom and on private life as well as on human identity are real and they raise recurring questions. The possible deviations in the use of these techniques, the temptations to "trespass the limits" are also common to info technologies and to biotechnologies but the threats triggered by the nanotechnologies are enhanced by the possibilities offered by the nanometric size and the expected convergence of these different technologies. One should refer to leading guiding principles in order to solve the future conflicts between the different sets of values, especially in the medical field by always remembering the Hippocratic oath "primum non nocere, deinde curare"