226Ra and 222Rn in geothermal waters of the Carpathian Basin

Complete text of publication follows. Due to favourable geology of the Carpathian many natural springs and drilled wells produce geothermal waters enriched in minerals. They represent significant economic and therapeutic value on which world famous bathing places developed in past centuries. Chemical composition of these waters has been extensively studied but less attention was paid to their radioactivity. Radon and radium content of waters may be interesting from different points of view. First, too much radon and radium in drinking water may pose health risk for humans. Second, radon and radium can be useful in tracing underground water transport. Therefore, cheap, reliable and accurate measurement of their concentrations has a great value. Etched track detector based simple method was developed in the Institute of Nuclear Research, Debrecen in the las years [1, 2]. In this work the radium and radon contents of thermal water of the springs and wells of the Gellert, Rac and Lukacs Baths as well as of the Rudas Drinking Hall in Budapest were measured. Samples from drinking-water wells of Feked, Szebeny, Vemend (near the Mecsek Mountain in Transdanubian region of Hungary) and about 50 mineral water samples were collected in Hargitha Country, Transylvania of Romania; in Slovenia and in the Great Hungarian Plain. The majority of the Romanian and Slovenian mineral waters have from low to moderate 226Ra activity concentration (<300 Bqm-3). The Hungarian geothermal waters show higher values up to some kBqm-3. 222Rn and 226Ra determination of other well-known medical waters are planned. Further studies of commercially available bottled mineral waters and of dosimetric consequences due to daily consume of these measured waters are in progress. This work was supported by the National Scientific Research Fund, No. T-22985. (author)