INAA applications in the assessment of minor and trace element contents in the soil of Moscow's park

Within recent ten years Moscow traffic increased greatly that made the ecological situation of the Russian capital much worse. The topsoil is a strong absorber of many chemical elements keeping them in the surface, the most fertile layer. So, samples of the soil surface layer can be advisably used as a bioindicator of the environmental state. Instrumental neutron activation analysis (INAA) was used to determine contents of chemical elements in topsoil (A-horizon) of one of the Moscow's park. It was shown that INAA allowed determining mass fraction of 26 chemical elements such as As, Ba, Br, Ca, Ce, Co, Cr, Cs, Eu, Fe, Gd, Hf, La, Lu, Nd, Rb, Sb, Sc, Sm, Sr, Ta, Tb, Th, U, Yb, and Zn in the soil samples even at the natural (uncontaminated) levels. The method allowed estimate levels of Ag, Au, Cd, Hg, and Se in soils too if concentrations of these elements are higher detection limits, 1.0, 0.02, 2.0, 0.1, and 0.5 μg/g, respectively. The mass fraction of 30 chemical elements out of 31 in the investigated topsoil were in good agreement with ranges of chemical element contents in the uncontaminated turf-podzol and loam soils of Europe and Central European part of Russia. The total contents of all measured chemical elements are within the range characteristic for 'norm' or 'clean' soil and do not exceed environmental quality standards for soils of Russia. (author)