Radionuclides Concentration in Water and Mud of Euganean Thermal District

Document Type : Original Research Paper


CNR - Institute of Inorganic Chemistry and Surfaces – Stati Uniti 4, 35127 Padova, Italy


The geothermal phenomena in the area nearby the Euganean Hills (near Padua, in Italy) are
known and exploited for therapeutic purposes since ancient times, and recently also for aesthetic purposes.
This paper presents the first characterization of the radionuclides content in the Euganean thermal waters and mud, extended to a great number of spas. In particular the radionuclides content of both the 238U and 232Th series in water and mud samples was determined. Moreover, for the first time the transfer of 226Ra and of 228Ra from water to mud during the maturation process was demonstrated and the comparison of 226Ra and of 228Ra activity concentration between mud and water was studied. An excess of “unsupported” 222Rn in water was measured. 226Ra enrichment was observed in “mature” mud, with respect to the “raw” mud. The absorption of radium through skin from mud application was evaluated. Also, it was possible to distinguish some muds prepared from different starting materials.