GROSS ALPHA AND BETA ACTIVITY IN MINERAL WATER FROM SOUTHWEST BULGARIA

The natural radioactivity levels of mineral water from certain most frequently used sources in Southwest Bulgaria were determined. The mineral water was investigated with regard to gross alpha and beta activity to determine whether the activity concentrations are below levels at which no further action is required. The measurements were made by Liquid Scintillation Spectrometer. The gross alpha and beta activity varied from ≤ 0.003 Bq/L to 0.671 Bq/L and from 0.054 and to 0.375 Bq/L, respectively. The values obtained in this study were compared with data reported by other authors in different countries and with reference values accepted for drinking water. The annual effective doses were calculated for all investigated waters for adult inhabitants assuming yearly consumption of 730 litres. The results show that the annual effective dose of ingestion of these water samples excluding one, are below the individual dose criterion of 100 µSv/y according to the World Health Organization recommendations.