Radium content in Bulgarian mineral waters

Abstract

This study presents the results of 226Ra content in 104 Bulgarian mineral waters as well as the investigated correlations between the physicochemical parameters, geological structure, and specific activity of 226Ra. The results show that the 226Ra activities range from <30 mBqL-1 to 4900 mBqL-1 with a mean value of 156 mBqL-1. The highest concentrations of 226Ra were measured in mineral waters originating from the carbonate strata, as the dominant geological structure. Thus it is well connected with the estimated moderate positive correlation between Ca2+, Mg2+, and Ra2+ cations in the water. The estimated annual dose shows large dispersion of values ranging from 6 ?Sv to 1000 ?Sv with a mean value of 32 ? 9 ?Sv. The results demonstrate the need for further investigation of every mineral water, but greater attention should be given to the mineral waters with low pH and high content of Ca2+ and Mg2+.