Accidental irradiation of an employee occurred in March 2005 in the CEA's Service Hospitalier Frédéric Joliot (SHFJ) located in the Orsay hospital.

This incident occurred during production of a fluorine 18-based radiopharmaceutical used in nuclear medicine. After noting a malfunction in the automated manufacturing process, an operator carried out an inappropriate manual intervention which led to body and clothing contamination. This contamination involved irradiation of the operator's right forearm, which was given specialist medical treatment.

After being informed of this incident, the ASN inspected the SHFJ, bringing to light inadequacies in the design of the installation and in the organisation for dealing with radiation protection incident situations. The ASN only authorised continued operation of the installation after confirmation was received that effective corrective measures had been taken and that new permanent operational procedures were in place, to prevent such an incident happening again.

Ten other fluorine 18 production installations are in operation in France and, jointly with the AFSSAPS and the Labour Inspectorate, the ASN carried out a series of checks on these installations in order to verify their personnel radiation protection arrangements. Further to these checks, the ASN asked for various corrective actions to be taken, to improve operator radiation protection.

In addition to conventional methods of tumour irradiation, new techniques called tomotherapy and radiosurgery should shortly start being used in France.

Tomotherapy combines scanner and particle accelerator technologies. A photon beam of 6 MeV and 8 Gy/mn irradiates a tumour using techniques inspired by the helical scanner (complete rotation around the patient and breakdown of the volume to be processed into basic cross-sections, which are irradiated). A multileaf collimator and modulation of the radiation intensity allow highly-localised irradiation of regions independently of each other. It is also possible to acquire images of the zone being irradiated and compare them with reference tomography images in order to improve patient positioning quality. This technique is currently employed in about fifty centres in the United States and Europe. Two devices of this type should be installed in France in 2006.

Radiosurgery consists in using a small particle accelerator placed on a robot arm with 6 degrees of freedom. By combining the robot's ability to move around the treatment table and the degrees of freedom of its arm, it is thus possible to use multiple, non-planar beams to irradiate small tumours that are difficult to access using conventional surgery and radiotherapy. At present, three centres in Europe (Belgium, Germany and Italy) are using this technique and one or two French teams should shortly be acquiring this equipment. Given the movement capabilities of the robot and its arm, the radiation protection of the treatment room does not correspond to the usual standards and will therefore require a specific study.

The routine use in nuclear medicine of fluorine 18, in the form of fluorodeoxyglucose (18FDG), for cancerology purposes, has opened the door to research into development of new radioactive tracers intended for both diagnosis and internal radiotherapy. Other than fluorine 18 marking on new vectors, current work in progress concerns the use of other radionuclides such as rubidium 82, copper 64 or iodine 124 for diagnostic applications. In the field of internal radiotherapy, research is beginning to look at using high-energy alpha (astatine 211, bismuth 213, radium 223 or actinium 225) or beta (copper 67, yttrium 90 or lutetium 177) emitting radionuclides.

The use in nuclear medicine of at least some of these radionuclides - if their medical interest can be proven - will require that the radiation protection requirements associated with their use be taken into account as early as possible. Given the activity levels potentially involved (usually far higher than those normally employed in nuclear medicine), the characteristics of the radionuclides and the preparation and administration protocols as today made known to the ASN, exposure of the operator - particularly the hands - could reach or exceed the regulatory dose limits, which is of course unacceptable to the ASN.

In these conditions and pending the initial licensing applications, the ASN is combining a reminder of regulatory requirements with awareness raising programmes, in particular by encouraging the development of automated systems for preparation and/or injection of these radioactive products.