Simultaneous determination of 210Pb and 90Sr and 210Po isolation in sludge samples using a plastic scintillation resin

This study describes a new and fast method for separating 210Po from 210Pb and 90Sr, before simultaneously measuring the individual activities of the latter two radionuclides using a plastic scintillation resin (PSresin) in sludge samples taken from a drinking water treatment plant. This method speeds up the analysis process significantly by simultaneously measuring 210Pb and 90Sr in a single step. The method is reproducible and has a relative standard deviation of less than 25% for 210Pb, 210Po and 90Sr. The method was satisfactorily validated with an intercomparison sample and applied to sludge samples from a drinking water treatment plant. The minimum detectable activities for 0.9 g of sludge are 5.5 Bq/kg and 8 Bq/kg for 210Pb and 90Sr respectively when measured for 180 min, and 0.5 Bq/kg for 210Po when measured for 5000 min.