The significant differences in the activities of ²¹⁰Pb, ²¹⁰Bi, ²¹⁰Po and cosmogenic ⁷Be and ²²Na radionuclides in the urban aerosol samples collected in the summers 2010 and 2011 in the Lodz city of Poland were observed. Simultaneous measurement of these radionuclides, after a simple modification of the one compartment model, allows us to calculate both: the corrected aerosol residence times in the troposphere (1 ÷ 25 days) and in the lower stratosphere (103 ÷ 205 days). The relative input of the additional sources (beside of the ²²²Rn decay in the air) to the total activity concentrations of ²¹⁰Pb, ²¹⁰Bi and ²¹⁰Po radionuclides in the urban air, plays a substantial role (up to 97% of the total activity) only in the case of ²¹⁰Po.

Low-energy X and γ radiations (for example of ²¹⁰Pb: E _γ = 46.5 keV) are effectively self-absorbed even in thin environmental samples, including air filters with captured dust or contaminated soil, as well as in bottom sediment matrixes with limited quantities of the samples. In this paper, a simple method for the direct analysis of ²¹⁰Pb (T _1/2 = 22.3 years) by gamma-ray spectrometry in environmental samples with self-absorption correction is described. The method is based on the comparison of two γ peak activities coming from other natural radionuclides, usually present in environmental samples. We have analyzed the dependence of the self-absorption correction factor for the ²¹⁰Pb activity on the activity ratios of 911 and 209 keV peaks and 609 and 295 keV peaks coming from nuclides of ²³⁸U or ²³²Th rows, present in typical environmental samples.