Three Types of Natural Radioactivity in Groundwaters

The authors collected data on concentrations of natural radionuclides (222Rn, 226Ra, 228Ra, 238U, 234U, 40K, 210Pb, 210Po, 3H, and 14C) in medicinal waters in Poland. Medicinal waters were chosen because they represent an almost complete spectrum of hydrochemical types and groundwater mineralization. The ranges of these concentrations are presented as divided into three regions: the Sudetes, the Carpathians and the Polish Lowlands. Medicinal waters of the Sudetes are characterized by the highest concentrations of 222Rn, 238U and 234U. The radioactivity of Carpathian medicinal waters is associated with the presence of 226,228Ra and 40K and, more rarely, 238,234U or 222Rn. Medicinal waters of the Polish Lowlands are characterized by increased concentrations of 226,228Ra and 40K, while 222Rn and the isotopes 238,234U occur in them in very low concentrations. In terms of natural radionuclide content three types of groundwaters can be defined. Medicinal waters of the Sudetes can be characterized as radium–uranium–radon waters (Rn > U > Ra; where 234U > 238U and 226Ra > 228Ra), of the Carpathians as radium–potassium waters (K > Ra; where 226Ra > 228Ra), and of the Polish Lowlands as potassium–radium waters (Ra > K; where 228Ra > 226Ra).