Determination of lead-210 and its progenies in aerosol fractions of different particles sizes

Determinations of 210Pb in aerosol fractions of particle sizes between 0.015 - 16 μm have been carried out from air volumes of 35 - 100 m3 by α-spectrometry via 210Po after equilibrium has been established, i.e. one or more years later, or directly by liquid scintillation spectrometry using pulse shape analysis immediately after sample collection. In this way also the 210Bi/210Pb and the 210Po/210Pb ratios have been obtained. Based on different models published in the literature aerosol residence times are discussed. (orig.)