Nowadays, a wide variety of nanoparticles (NPs) are applied in different fields such as medical science and industry. Due to their large commercial volume, the OECD Working Party on Manufactured Nanomaterials has proposed to study a set of 14 nanomaterials, one of which being cerium oxide (CeO2). In particular, CeO2 based NPs are widely used in automotive industry, healthcare and cosmetics. In this paper, we propose a method for the production of radioactive CeO2 NPs. We demonstrate that they maintain the same physicochemical characteristics as the ¿cold¿ ones in terms of size distribution and Zeta potential; we develop a new protocol to assess their cellular interaction in immortalized mouse fibroblast cell line Balb/3T3, a model for the study of basal cytotoxicity and carcinogenic potential induced by chemicals and in the present case by NPs. One experimental result of this work, which shows a quasi-linear concentration-uptake response of cells, can be useful as a reference dose-uptake curve for explaining effects following biological uptake after exposure to CeO2 NPs. ; JRC.DG.I.5-Nanobiosciences