Radioactivity measurements and radiation dose evaluation in tap waters of Central Italy

Consumption of drinking water is very important for human nutrition and its quality must be strictly controlled. A study of radioactivity content in tap waters collected in the Central Italy was performed in order to check the compliance with recent European regulations. Gross alpha and beta activity, 226Ra, 238U and 234U concentrations were measured. Gross alpha and beta activities were determined by standard ISO 9696 and ISO 9697; liquid scintillation was usedfor 226Ra determination. 238U and 234U concentrations were determined by alpha spectrometry after separation from matrix by extraction chromatography and electroplating. Recommended WHO guideline activity concentrations for drinking water (0.1 Bq L-1 and 1.0 Bq L-1 for gross alpha and gross beta activity respectively) are exceeded in 2 cases for gross alpha activity and are not exceeded in any case for gross beta activity. The concentrations (mBq L-1) of 226Ra, 238U, 234U ranged from