Active biomonitoring of air radioactivity in urban areas

To assess the validity of the moss bag monitoring technique in the radioactivity control of ground level urban air, a study on radionuclide contents in moss was performed in the city of Belgrade, Serbia. From May 2006 to May 2007, moss (Sphagnum girgensohni, Dubna, Russia) was exposed to the aero pollution in a location in the central area of the city. The activity of 40K, 210Pb, and 137Cs was measured on an HPGe detector (Canberra, relative efficiency 23%) by standard gamma spectrometry. The activities 245 ± 25 Bq/kg for 40K, 315 ± 34 Bq/kg for 210Pb, and 28 ± 4 Bq/kg for 137Cs are in the range of values reported for the region; the differences are due to the moss species, local climate and measuring technique. Taking into consideration the time of the exposure and appropriate calibration procedure, moss bag biomonitoring could be used as a complementary method for determination of radionuclides in urban air. (author)