Simultaneous determination of 210Pb and 212Pb progenies by liquid scintillation counting

A time efficient method has been developed for separation and measurement of 210Pb and 212Pb and its progenies in aerosol samples. After leaching, transferring to a sulphate system and adding a certain amount of HCl, Po and Bi isotopes are extracted into a liquid scintillation cocktail and measured simultaneously using pulse shape analysis. 210Pb is measured from the ingrown 210Bi after ca 2 weeks or measured directly in the aqueous phase. The lower limits of detection are 0.2 mBq for 210Po and 212Bi, and 0.5 mBq for 210Bi.