Chemometric methods for source apportionment of Pb, Bi and Po for 10 years of urban air radioactivity monitoring in Lodz city, Poland.

The radionuclide activity concentrations of Pb and its decay products Bi and Po were measured in 271 total suspended particulate samples collected from 2008 to 2017 in the center of Lodz city, Poland. Natural and anthropogenic contributions to the observed activities of Pb, Bi and Po radionuclides were estimated. Corrected aerosol residence times were determined for this purpose. After the closure of one of the coal-fired power plants located in the center of the city, a substantial reduction in emission of these radionuclides was observed. For proper identification of the origins of these radionuclides, the concentrations of  K and Be as well as sulfur dioxide (SO and total air particulate matter were measured. Principal component analysis and cluster analysis were conducted for source apportionment of Pb, Bi and Po in urban air.