In its report submitted to the ministers in 1999, the GRNC indicated the need to carry out further studies so that some gaps in the knowledge of radiological parameters are filled, and recommended to take into account aspects other than the radiological ones. Further to these recommendations, the ministers of State of Health and Environment assigned the GRNC the responsibility of a second mission (study of uncertainties on the first mission results, and consideration of chemical releases). Then, about the radiological data used, thanks to various studies recently published by the IRSN, information concerning radionuclide concentrations, not mach studied until then, bas been obtained and parameters have been specifïed. Completely new information bas been acquired as chlorine-36 information. In the present text are summarized the scientific contributions obtained since the GRNC report publication.