Studies on the determination of transfer factors (TF) for 137Cs and 90Sr isotopes from soil to plant are presented. Experiments were performed on grass from meadows of Bug river valleys and vegetables from Zwierzyniec region. The influence of potassium and calcium on the transfer factor of both isotopes is discussed.
Some results of the extraction of strontium and yttrium from soil samples by concentrated nitric acid are described. The concentration of Sr and Y in the solid was determined by XRF method. The results obtained allowed to elaborate the conditions of acid leaching and to propose an analytical procedure for the determination of 90Sr in samples without their total dissolution.
Contamination of ground level air at Lublin town was studied by measurements of radioactive isotope and heavy metal contents in Parmeliaceae lichens exposed during six months on the area of the town. The concentration of the elements studied was compared with these ones measured in unexposed (blank) samples of lichens. The highest increase of radioactivity was noticed for 232Th, 226Ra and 40K. The contamination by 137Cs does not increased markedly, ranging from 2 to 107 Bq/kg of the dry lichen sample. Nearly half of the exposed samples do not reveal any increase of cesium radioactivity. Heavy metal concentrations in analyzed lichens were low. From the results obtained, one may conclude that concentration of these metals in ground air level does not reach appreciable values.
An investigation of the presence of some radioactive isotopes in the bottom sediments of two lakes, Piaseczno and Masluchowskie (Middle East of Poland) has been performed. Similar measurements were done at the Zalew Zemborzycki artificial water reservoir, filled up few years after the most intensive period of atmospheric nuclear explosions. It was estimated, that the concentration of radionuclides, especially of artificial origin was much greater in natural lakes than in examined artificial one. That testifies for an accumulation of radioactive substances on the bottom of the water tanks. The confirmation of this thesis may be the fact, that 85% of137Cs detected in Zalew Zemborzycki comes from Chemobyl fallout while in natural lakes this isotope amounts only to 56–60%. Other isotopes, such as210Pb,226Ra, and224Ra were detected in significant amounts. The radioactivity of239,240Pu isotopes reaches 2.2–2.6 Bq/kg for the lakes and 0.7 for Zalew Zemborzycki. The238Pu to239,240Pu ratio suggests, that detected plutonium comes from world fallout.
Radioactivity of 90Sr and 137Cs in several species of herbs collected at Fajsawice and Góra Puawska located in Lublin (Poland) region was examined. Depending on the type of herb the radioactivity of strontium ranged from 0.004 to 1.808 Bq/kg dry weight whereas that from cesium varied from 0.053 to 9.853 Bq/kg. Calculated transfer factors of the radioisotopes in the plants studied revealed much stronger accumulation of strontium than cesium. Concentration of calcium and potassium in these plants has no influence on the concentration of measured radioisotopes.
The results of investigations of the level of contamination by γ-radioactive isotopes of lichens fromParmeliaceae family, collected in the years 1949–1996 are presented. The most important isotope, occurring in significant amount was137Cs. From the natural isotope group also40K,226Ra,210Pb,234Th and214Bi were found in few samples. Starting from 1956, the137Cs isotope is detected in all collected samples with two distinct maxima in 1963 and 1989. Taking into accunt the age of the
collected lichens, their activity and the level of the radioactivity fall-out, the full correlation of the obtained results
with the amount of the radioactive fall-out is observed.
The results of field, column and laboratory studies carried out on three types of mineral soils are encloses presented. Based
on the field tests, average migration rates of137Cs were calculated. The highest rate was found for the brown soil (FAO/UNESCO—Cambisol). Cesium migrated with the lowest rate
in the podzol soil (FAO/UNESCO—Cambic Podzol). The column experiments confirmed the above observation. In laboratory tests
the adsorption and desorption isotherms of Cs were determined on samples taken from 0–2 cm layers of each soil profile. It
was found from the calculated partition coefficients that Cs is always irreversibly bonded to some extent, but it appears
to be completely and irreversibly immobilized on the podzol soil. The permanent retention of cesium in the podzol soil was
also confirmed by microcalorimetric studies. The desorption energy was negligibly small and amounted to −0.21 mJ/g. In the
brown soil, containing prevailing amounts of loamy minerals, the desorption energy was found to be 106.89 mJ/g. The investigations
are supplemented by the sorption kinetics measurements. These indicate that the adsorption equilibrium is reached after a
dozen, up to twenty or so minutes.
The vertical distribution of137Cs is shown for two types of soil: silly loamy “supposed” soil and silly lessive one, slightly eroded, occuring in the vicinity
of Lublin (Eastern Poland). Based on the distribution data the vertical migration rates of137Cs are calculated for both soils. These rates are found to be 0.045 and 0.3 cm/year respectively. The percent contribution
of137Cs originating from the damaged reactor in Chernobyl is also calculated. The kinetics of cesium adsorption and its adsorption
isotherms on minerals separated from the tested soils are also studied. The sorption of Cs on soil minerals markedly affects
the migration rate of137Cs in soil. The experimental results indicate that, among the extracted mineral fractions, the largest adsorption takes place
on marls from the silly loamy soil. This work is supplemented by results of a physicochemical analysis of the studied soils.
The level of artificial and natural radionuclide concentration as well as heavy metal content were determined in samples of
saw sedge and peat collected in the Special Protection Area of peat bogs near Chelm (Poland). Gamma- and alpha-spectrometry
with proper sample preparation were used to determine natural gamma-emitters, artificial 137Cs and alpha-radiating plutonium (238Pu and 239,240Pu). Non radioactive elements were determined by AAS. Rather low level of heavy metal concentration in all samples was found,
however, the transfer factors were significant. Peat contamination with artificial radionuclides (137Cs and plutonium) was low. Contrary, the concentration of these isotopes in saw sedge was higher than normally observed in
non contaminated areas, what is a result of a significant transfer factor.
Results of determination of 137Cs, 90Sr, 40K, 239+240Pu, and heavy metals: Mn, Zn, Pb, Cd, Ni, Cr, Co, and Cu in skeletons of 15 species of birds of prey from Eastern Poland were
presented. The greatest amounts of 137Cs and 90Sr (70 Bq/kg and 33 Bq/kg, respectively) were found in rough-legged buzzards (Buteo lagopus), winter visitors, coming from former soviet nuclear test places. Concentrations of 239+240Pu in raptors were negligible, only lesser-spotted eagles (Aquila pomarina) revealed slightly higher values. Median concentrations of 137Cs and 90Sr in raptors which feed predominantly on small mammals were higher in comparison to concentrations found in other ones preferring
different trophy. The most noticeable was a very high lead concentration (reaching above 600 mg/kg) in birds which utilize
un-retrieved hunting casualties as their prey.