Radionuclidi naturali in ghiaie e sabbie delle cave della pianura lombarda

To estimate indoor exposure due to building materials in Lombardy, a study to determine the radionuclide concentrations of gravel and sand samples coming from some quarries located in lombard plain has been carried out. 70 quarries were studied, placed mainly along the Po tributaries and the Po too. The concentrations of Ra-226, Th-232 and K-40 cover a range from 20-30 Bq/kg, 15-35 Bq/kg, 250-650 Bq/kg, respectively. The samples of Chiese river area, with values of about 50 Bq/kg for Ra-226, of 5-10 Bq/kg for Th-232 and about 100 Bq/kg for K-40 are an exception.