Natural radionuclides measurements and total dose indicative evaluation in drinking waters of an Italian central region.

A study of radioactivity content in drinking waters collected in some areas of geological interest in an Italian central region was performed to check the compliance with recent European regulations. Gross alpha and beta activities, Ra-226, U-238, U-234, Po-210 and(3)H concentrations were measured. Gross alpha and beta, Ra-226 and H-3 activities were determined using an ultra-low-level scintillation counter, U-238, U-234 and Po-210 by alpha spectrometry after radiochemical separation. Recommended WHO guideline activity concentrations for drinking water were exceeded in 6 cases for gross alpha activity and were not exceeded in any case for gross beta activity. Tritium concentration was always lower than MDA (6.75 Bq L-1); the concentrations (mBq L-1) of 226Ra, 238U, 234U and 210Po ranged from < 1.80 to 23.00, from 1.20 to 140.00, from 1.60 to 120.00 and from 0.25 to 5.90, respectively. Due to the importance of the water in human diet, the doses were calculated for children and adults using the dose coefficient factors reported by EC Directive 96/29 EURATOM and annual water intake; all samples furnished a dose lower the reference level for drinking water (0.1 mSv y(-1)).