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The accumulation of unwanted long-lived radionuclides during the production of 18F-based radiopharmaceuticals using the IBA Cyclone 18/9 HC cyclotron is considered. Using high-resolution gamma-ray spectrometry with HPGe detectors, the identification of radionuclides and the assessment of activity in activated components (stripper, target entrance window) of the "medical" 18-MeV cyclotron IBA Cyclone 18/9 were carried out. More than 20 unwanted radionuclides have been identified in irradiated water. Various mechanisms for the entry of longlived radionuclides into irradiated water are described. The results obtained are of great importance for optimizing the methods of radioactive waste management in the production of radiopharmaceuticals and, as a result, minimizing the radiation exposure of personnel.

In this paper, the radiological and economic issues of dismantling cyclotrons of various types, the accumulation of radionuclides in the details of the cyclotron itself, and the activation of the walls of the cyclotron bunker due to the capture of secondary neutrons are considered. As a result of (n,γ)-reactions on thermal neutrons, radionuclides 152Eu, 60Co, 46Sc are formed in the concrete of the cyclotron bunker with a half-life of 2,6 to 14 years and an activity of 0,1–11 kBq/kg. The maximum of their distribution usually lies at a depth of 10–15 cm. In the details of the cyclotron and the metal infrastructure of the bunker, the main radionuclides are 54Mn, 57Co, 65Zn. The analysis of the accumulation of long-lived radionuclides is of great importance for the design of new cyclotron facilities in order to ensure radiation safety and storage of radioactive waste and, as a result, to minimize the radiation exposure of personnel during the dismantling of the cyclotron.

Simultaneous measurements of γ- and β-emitting radionuclides in regenerated water and sorption purification cartridges used in the production of radiopharmaceuticals based on 18F were carried out with the MKSAT1315 spectrometer. It was found that the bands observed in the gamma-spectra are due to isotopes of cobalt 55Co, 56Co, 58Co, 57Co, nickel 57Ni, manganese 54Mn and zinc 65Zn, the prospects of using the gamma-beta spectrometer MKS-AT1315 for operational control of the content of undesirable technological radionuclides in the production of radiopharmaceuticals based on 18F are shown.