title: Leaves of higher plants as biomonitors of radionuclides (137Cs, 40K, 210Pb and 7Be) in urban air.
abstract: Leaves of linden (Tilia tomentosa L. and Tilia cordata Mill.) and horse chestnut (Aesculus hippocastanum L.) were analysed as biomonitors of radionuclides in urban air. Samples of soils, leaves and aerosols were collected in Belgrade, Serbia. Activities of (137)Cs, (40)K, (210)Pb and (7)Be in the samples were measured on an HPGe detector by standard gamma spectrometry. "Soil-to-leaves" transfer factors were calculated. Student's t test and linear Pearson correlation coefficients were used for statistical analysis. Differences in local conditions at the sampling sites were not significant, and the mechanisms of the radionuclides' accumulation in both plant species are similar. Ceasium-137 was detected in some of the leaf samples only. Transfer factors for (137)Cs and (40)K were (0.03-0.08) and 1.3, respectively. The concentrations of (210)Pb and (7)Be in leaves were higher in autumn than in spring, and there were some similarities in their seasonal patterns in leaves and in air. Weak to medium correlation was obtained for the (210)Pb and (7)Be activities in leaves and aerosols. Large positive correlation was obtained for the (210)Pb activities in linden leaves and the mean activity in aerosols for the preceding months. Different primary modes of radionuclides accumulation in leaves were observed. Since large positive correlation was obtained for the (210)Pb activity in linden leaves and the mean in aerosols for the preceding months, mature linden leaves could be used as biomonitors of recent (210)Pb activity in air.
authors.affiliation: Department of Radiation and Environmental Protection, Institute of Nuclear Sciences Vinča, University of Belgrade, PO Box 522, 11001 Belgrade, Serbia.
authors.forename: Dragana
authors.initials: D
authors.lastname: Todorović
authors.forename: Dragana
authors.initials: D
authors.lastname: Popović
authors.forename: Jelena
authors.initials: J
authors.lastname: Ajtić
authors.forename: Jelena
authors.initials: J
authors.lastname: Nikolić
mesh_terms: D000396:Air Pollutants, Radioactive / Q000032:analysis*; D001608:Beryllium / Q000032:analysis; D002588:Cesium Radioisotopes / Q000032:analysis; D002947:Cities; D007856:Lead Radioisotopes / Q000032:analysis; D018515:Plant Leaves / Q000737:chemistry*; D011197:Potassium Radioisotopes / Q000032:analysis; D011834:Radiation Monitoring / Q000379:methods*; D011868:Radioisotopes / Q000032:analysis*; D055771:Serbia
chemical_list: D000396:Air Pollutants, Radioactive; D002588:Cesium Radioisotopes; D007856:Lead Radioisotopes; D011197:Potassium Radioisotopes; D011868:Radioisotopes; D001608:Beryllium