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Vertical profiles of 137Cs and 239,240Pu were measured in soils collected from two sites in southern Sweden and three sites in southern Poland and were modeled using both a solute transport model and a bioturbation model to better understand their downward migration. A time series of measured 137Cs profiles indicates that 137Cs from Chernobyl was found at the soil surface in 1986 but it has migrated progressively downward into the soil 4.5–25.5 cm since. However, because of dispersion during the migration and mixing following Chernobyl deposition and the much higher activities of 137Cs from Chernobyl, stratospheric fallout of 137Cs from the 1960s cannot be identified as a second 137Cs activity maximum lower in the soil column at any of the sites. Conversely, the 240Pu/239Pu ratio indicates that no Chernobyl-derived Pu is present in any of the cores with the exception of one sample in Sweden. This difference may be attributed to the nature of the release from Chernobyl. Cesium volatilized at the reactor temperature during the accident, and was released as a vapor whereas Pu was not volatile and was only released in the form of minute fuel particles that traveled regionally. Both the solute diffusion and the bioturbation models accurately simulate the downward migration of the radionuclides at some sites but poorly describe the distributions at other sites. The distribution coefficients required by the solute transport model are about 100 times lower than reported values from the literature indicating that even though the solute transport model can simulate the profile shapes, transport as a solute is not the primary mechanism governing the downward migration of either Cs or Pu. The bioturbation model uses reported values from the literature of the distribution coefficients and can simulate the downward migration because that model buries the fallout by placing soil from depth on top and mixing it slightly throughout the mixing zone (0.6–2% per year of mixing). However, mixing in that model predicts concentrations in the top parts of the soil profiles which are too high in many cases. Future progress at understanding the downward migration of radionuclides and other tracers will require a more comprehensive approach, combining solute transport with bioturbation and including other important soil processes.

Fruiting bodies of fungi belonging to more than 70 species were collected within a few thousand square meter area of one forest during 2006 and 2007. The soil profile was collected to check the cumulative deposition of 137 Cs, which was relatively high, equal to 64 ± 2 kBq/m 2 (calculated for October 2006). The majority of this activity was in the first 6 cm. Fruitbodies were analyzed for radiocesium and 40 K by means of gamma-spectrometry. The highest 137 Cs activity was 54.1 ± 0.7 kBq/kg (dry weight) for a sample of Lactarius helvus collected in 2006. The results for 2006 were higher than those for 2007. In a few cases the traces of short-lived (T 1/2 = 2.06 a) 134 Cs were still found in samples. The importance of mycorrhizal fungi for radiocesium accumulation is confirmed. The differences in activity among the species are discussed in relation to observations and predictions from previous studies, where the change in relative accumulation between fruiting bodies of different species was at least partially explained by the differences in the depth of the mycelium localization in a litter/soil system. It is concluded that in some cases, such as Boletus edulis and Xerocomus badius , this prediction is fulfilled and therefore this explanation confirmed.

Results are presented for 137 Cs, 90 Sr and plutonium activity concentrations in more than 20 samples of terrestrial invertebrates, including species of beetles, ants, spiders and millipedes, collected in the highly contaminated area of the Chernobyl exclusion zone. The majority of samples were collected in Belarus, with some also collected in the Ukraine. Three other samples were collected in an area of lower contamination. Results show that seven samples exceed an activity concentration of 100 kBq/kg (ash weight – a.w.) for 137 Cs. The maximum activity concentration for this isotope was 1.52 ± 0.08 MBq/kg (a.w.) determined in ants ( Formica cynerea ). Seven results for 90 Sr exceeded 100 kBq/kg (a.w.), mostly for millipedes. Relatively high plutonium activity concentrations were found in some ants and earth-boring dung beetles. Analyses of activity ratios showed differences in transfer of radionuclides between species. To reveal the correlation structure of the multivariate data set, the Partial Least-Squares method (PLS) was used. Results of the PLS model suggest that high radiocesium activity concentrations in animal bodies can be expected mainly for relatively small creatures living on the litter surface. In contrast, high strontium activity concentrations can be expected for creatures which conduct their lives within litter, having mixed trophic habits and a moderate lifespan. No clear conclusions could be made for plutonium.

Sediment deposits are the ultimate sink for anthropogenic radionuclides entering the marine environment. The major sources of anthropogenic radionuclides to the Barents Sea are fallout from nuclear weapons tests, long range transport from other seas, and river and non-point freshwater supplies. In this study we investigated activity concentrations, ratios, and inventories of the anthropogenic radionuclides, 137Cs, 238Pu, 239,240Pu in dated sediment cores collected along a north-south transect in the northwestern Barents Sea. The data were used to evaluate the influence of different sources on the derived spatial and temporal patterns of anthropogenic radionuclides in seafloor sediment deposits. Activity concentrations of 137Cs ranged from

The paper deals with a specific aspect of a general survey, that is being carried out during last ten years in several regions of Serbia (former Yugoslavia, former Serbia and Montenegro) to assess population exposure to natural radioactivity based on geochemical and integrative pattern research approach. The originality regarding this work is related to the facts such as follows: the first identification and assessment of high areas of natural radiation in Serbia which provides insight into its regional characteristics, the interpretation of the results in terms of geological aspects, building types and human habits, the first introduction and field applicability of both (surface and volume trap) retro techniques in Serbia and assessment of doses and risks to the population in investigated high natural radiation rural communities.

This paper reports results of gamma and alpha spectrometric measurements for mosses, lichens, fungi and soil samples from areas in the Balkans targeted by depleted uranium (DU). Samples were collected in 2002 and 2003 in the vicinity of several villages, principally Han Pijesak: (Bosnia and Herzegovina, hit by DU in 1995) and Bratoselce (South Serbia, hit by DU in 1999) and in lesser numbers from Gornja Stubla, Kosovo (which is identified as a high natural radon/thoron area) and Presevo close to the Kosovo border. In the course of gamma spectrometric measurements some results suggested samples with unusual high uranium contents which might be considered to be a signature for the presence of DU, although many samples had very high detection limits. Alpha spectrometric measurements directly proved the presence of DU for five samples, all from directly targeted places. These were samples of mosses, lichens and soil. For some samples homogeneity tests were applied which showed a rather even distribution of DU in these samples. No trace of DU was found in any sample from a dwelling. (C) 2008 Elsevier Ltd. All rights reserved.

There are few data reported on radionuclide contamination in Antarctica. The aim of this paper is to report 137Cs, 90Sr and 238,239+240Pu and 40K activity concentrations measured in biological samples collected from King George Island (Southern Shetlands, Antarctica), mostly during 2001–2002. The samples included: bones, eggshells and feathers of penguin Pygoscelis papua, bones and feathers of petrel Daption capense, bones and fur of seal Mirounga leonina, algae Himantothallus grandifolius, Desmarestia anceps and Cystosphaera jacquinotii, fish Notothenia corriceps, sea invertebrates Amphipoda, shells of limpet Nacella concina, lichen Usnea aurantiaco-atra, vascular plants Deschampsia antarctica and Colobanthus quitensis, fungi Omphalina pyxidata, moss Sanionia uncinata and soil. The results show a large variation in some activity concentrations. Samples from the marine environment had lower contamination levels than those from terrestrial ecosystems. The highest activity concentrations for all radionuclides were found in lichen and, to a lesser extent, in mosses, probably because lichens take up atmospheric pollutants and retain them. The only significant correlation (except for that expected between 238Pu and 239+240Pu) was noted for moss and lichen samples between plutonium and 90Sr. A tendency to a slow decrease with time seems to be occurring. Analyses of the activity ratios show varying fractionation between various radionuclides in different organisms. Algae were relatively more highly contaminated with plutonium and radiostrontium, and depleted with radiocesium. Feathers had the lowest plutonium concentrations. Radiostrontium and, to a lesser extent, Pu accumulated in bones. The present low intensity of fallout in Antarctic has a lower 238Pu/239+240Pu activity ratio than that expected for global fallout.

90Sr, 238,239+240Pu, 241Am and 137Cs activity concentrations are presented in the jaw bones of red fox (Vulpes vulpes) from eastern Poland. The short description of the applied radiochemical method is presented. Activity concentrations for 90Sr ranged between 2.2±0.7 and 41.4±4.7 Bq/kg (aw = ash weight). Average results for plutonium and americium are on the level of 10 mBq/kg (aw). No clear relationship was observed among the radionuclide concentrations. The samples analyzed do not show elevated contamination levels when compared with results of bones of small animals (rodent or insectivorous mammals) determined previously, so no accumulation of bone seeking isotopes on higher step of food-chain is concluded.

Activity concentrations and inventory for 238Pu, 239+240Pu, 241Am, 90Sr, and 137Cs in soil from Tatra Mountains of Poland are presented. Soil samples were collected using 10 cm diameter cores down to 10 cm and sliced into 3 slices. Details of the applied procedure are described with the quality assurance program. The maximum activity concentrations found for various samples were: 1782±13 Bq/kg, 17.4±0.9 Bq/kg, 3.4±0.3 Bq/kg and 84±7 Bq/kg for 137Cs, 239+240Pu, 241Am and 90Sr, respectively. The maximum cumulated deposition of 239+240Pu is 201±8 Bq/m2. The origin of radionuclides is discussed, based mostly on the observed isotopic ratio of Pu. Significant correlations were found between 239+240Pu, 241Am and 137Cs. The effective vertical migration rate seems to be in the order of: 90Sr≫Pu>Am>Cs.

The present study focused on analyzing samples of bones, livers and kidneys of European white-tailed eagles (Haliaetus albicilla) and lesser-spotted eagle (Aquila pomarina). Bone samples were collected for both species, from 7 and 2 individuals, respectively, whereas liver and kidney samples for white-tailed eagle species only, 2 and 1 individuals, respectively. The samples were analyzed for the presence of gamma-emitters and then for 90Sr, 238Pu, 239+240Pu and 241Am. The applied radiochemical method is presented. Activity concentration in ashen bones (600 °C) for 90Sr ranged from 4.6±1.2 to 31.0±2.5 Bq/kg, for 239+240Pu from

Summary The paper presents results on determination of 90Sr in bilberry and cowberry leaves (Vaccinium myrtillus and Vaccinium vitis-idaea) and the use of these plants as bio-monitors of radiostrontium contamination in Poland. Radiostrontium was determined by mean of liquid scintillation spectrometry preceded by radiochemical separation using Sr-resin and 85Sr tracer. The approximate map of 90Sr contamination of Poland is presented. The activity ratio between 90Sr and obtained earlier data for 137Cs in the same samples is discussed. The enhancement of radiostrontium content observed in northeastern Poland seems to be the trace of hot-particles fallout from initial Chernobyl cloud, which passed over Polish territory toward Scandinavia.

Summary Fungi have up to now generally been used as bioindicators of radiocaesium in terrestrial ecosystems. However there is little knowledge about the behaviour of other man-made radionuclides. In the present work, we analyzed the soil-to-fungi transfer of 90Sr, 239+240Pu, and 241Am by collecting several species of fungi and the corresponding surface soil (0−5 cm) of a selected semi-natural ecosystem. The transfer of these radionuclides was then quantified by means of the traditional transfer factor, TF, defined as the ratio between the content in the fruiting bodies and in the total fraction of soil. As a general rule, the 90Sr TF values were higher than those of 239+240Pu and 241Am. This definition of the transfer factor can underestimate the transfer of radionuclides of which a large percentage are bound to soil particles. We therefore also used a definition based on the amount of radionuclide available to be transferred instead of the total content of the soil — the available transfer factor, ATF — which would be closer to the actual process of transfer. Hebeloma cylindrosporum and Lycoperdon perlatum presented 239+240Pu and 241Am ATF values that were greater than or similar to those of 90Sr. These species may thus be used as bioindicators for 239+240Pu and 241Am in a forest ecosystem.

Skulls of small mammals belonging to two species of rodents and three species of insectivores collected in Eastern Poland were the subject of the present investigation. The skulls were separated from owl pellets. Activities of 40K, 137Cs, 90Sr, 238,239+240Pu and 241Am were determined by means of gamma spectrometry as well as liquid scintillation spectrometry or alpha spectrometry along with relevant radiochemical procedures. A detailed description of the procedures is provided. The research was supplied with the analysis of three skeletons of owls. No measurable difference between the skulls of rodents and insectivorous animals with regard to activity of any of the examined radionuclides was found. No accumulation effect in the owl skeletons was detected. Though measured activities of 137Cs and 40K for the skulls were of the same magnitude as those found previously for large wild herbivorous animals from typical locations in Poland, those for 90Sr were even lower than previously determined. A big difference was found for activities of plutonium and americium isotopes. Their mean activities were higher by an order of magnitude when compared to the examined previously values. The maximum 239+240Pu activity was equal to 97.5+/-7.7 mBq/kg, with 65% of it originating from global fallout. Relatively high content of transuranic elements found for rodents and insectivorous mammals seems to be unrelated to their feeding habits and should rather be attributed to the living conditions. It is suggested that small mammals, together with tiny soil particles present in mid-soil living tunnels, can inhale the transuranic elements.

Results for 137Cs, 40K, 90Sr, 238,239+240Pu, 241Am and 243+244Cm measurements in plant, insects and forest litter samples collected at three sites in Poland are presented. New results are compared with some existing data for locations examined during previous studies. Insect samples were introduced now for the first time. Relatively high activities of 90Sr were noticed for spruce bark beetle (Ips typographus) and those for 137Cs, plutonium and 241Am for forest dung beetle (Anoplotrupes stercorosus). Faster than caused by physical decay decrease of radiocesium activity was noticed for the majority of plant and litter samples. The results for 239+240Pu for litter were similar to previous results, but the activities of 238Pu were smaller. The activity ratio between 241Am and 239+240Pu was found lower than expected for known proportions between global and Chernobyl fallout. Thus a kind of dynamic behavior of Pu and Am in the forest ecosystem is concluded. Transfer factors and aggregation coefficients were estimated and discussed for both plants and insects as well as between insects and the part of plants (or litter) they feed on. Many of them were never presented before.

Sector inductively coupled plasma mass spectrometry is a versatile method for the determination of plutonium activities and isotopic compositions in samples containing this element at fallout levels. Typical detection limits for 239 + 240Pu are 0.1, 0.02 and 0.002 Bq kg−1Pu for samples sizes of 0.5 g, 3 g, and 50 g of soil, respectively. The application of sector ICP-MS-based Pu determinations is demonstrated in studies in sediment chronology, soil Pu inventory and depth distribution, and the provenance of global fallout versus local or regional Pu sources. A sediment core collected from Sloans Lake (Denver, Colorado, USA) exhibits very similar 137Cs and 239 + 240Pu activity profiles; 240Pu/239Pu atom ratios indicate possible small influences from the Nevada Test Site and/or the Rocky Flats Environmental Technology Site. An undisturbed soil profile from Lockett Meadow (Flagstaff, Arizona, USA) exhibits an exponential decrease in 239 + 240Pu activity versus depth; 240Pu/239Pu in the top 3 cm is slightly lower than the global fallout range of 0.180 ± 0.014 due to possible regional influence of Nevada Test Site fallout. The 239 ± 240Pu inventory at Lockett Meadow is 56 ± 4 Bq m−2, consistent with Northern Hemisphere mid-latitude fallout. Archived NdF3 sources, prepared from Polish soils, demonstrate that substantial 239 + 240Pu from the 1986 Chernobyl disaster has been deposited in north eastern regions of Poland; compared to global fallout, Chernobyl Pu exhibits higher abundances of 240Pu and 241Pu. The ratios 240Pu/239Pu and 241Pu/239Pu co-vary and range from 0.186–0.348 and 0.0029–0.0412, respectively, in forest soils (241Pu/239Pu = 0.2407·[240Pu/239Pu] − 0.0413; r2 = 0.9924).

The Petryanov air filters combined into half-year sets were analyzed for the presence of 40K, 137Cs and 22Na by means of low-background gamma rays spectrometry. Each sample contains aerosols from more than 1 Mm3 of air. Samples were collected in ground level air at Krakow (Southern Poland) from 1996 to 2002. Activity concentrations of 40K are almost constant with the mean of 14.7± 4.5 μ Bq m−3. Activity concentrations of 137Cs, which are on the level of single μ Bq m− 3 show exponential decrease with effective half-life time of 7.07± 0.77 years. The cosmogenic 22Na shows a strong seasonal variation with significant different mean values activity concentration between 0.333± 0.095 μ Bq m−3 and 0.137± 0.045 μ Bq m−3, for summer and winter, respectively. Moreover, the activity ratio for two cosmogenic radionuclides: 22Na and measured previously 7Be show also changes with statistically significant seasonal differences. The lower values were found during winters. The mechanisms which might govern this ratio are discussed. The conclusion is that transport of 22Na during summer seems to be so much effective, that results in kind of relative depletion of stratosphere of this nuclide.

Activity concentration of 90 Sr and stable strontium concentration was analysed in 42 samples of animal (deer, roe-deer, elk and boar) bones, which mostly originated from north-eastern Poland. Strontium separation was performed by extraction chromatography. Determination of chemical yield was controlled by means of stable Sr determination using atomic spectrometry at the beginning and at the end of the separation procedure. Equilibrated 90 Sr and 90 Y activity was measured using a liquid scintillator spectrometer. Stable strontium range was from 55.4±1.7 ppm to 91.8±4.5 ppm, the mean was 71.84 ppm with a standard deviation (SD) of 9.31 ppm. The mean recovery of strontium was 26.7% with SD = 16.1%. The maximum activity of 90 Sr, equal to 629±13 Bq/kg (ash) was found for a deer sample from Augustow Primeval Forest. In average, deer show the highest radiostrontium level, followed by roe-deer, elk and the lowest level were observed for boar. Differences between boar and deer or roe-deer are significant in terms of Kruskal-Wallis statistical test. Animal bones from north-eastern Poland showed about twice the mean concentration of 90 Sr, compared to those of south-central Poland, but the difference was found not significant. Activities observed in roe-deer bones suggest the deposition of a concentration of 1.9 to 3.5 kBq/m2 in the average of Chernobyl-origin 90 Sr in 1986 in north-eastern Poland.

Results of 63Ni and 60Co determination in forest litter samples collected in 2007 in highly contaminated Chernobyl exclusion zone as well as in isolated “ruthenium hot particles” collected in 1986 in Northeastern Poland are presented. In case of bulk samples relatively complicated radiochemical procedure was necessary for nickel separation from matrix elements and other radioisotopes present. The main steps in radiochemical operations were cobalt separation on Dowex 1×8 anion-exchange resin and separation of most of the matrix elements under basic conditions. Nickel was precipitated with sodium sulfide and when dissolved in aqua regia, Ni-DMG complex was formed, extracted with chloroform and back-extracted with hydrochloric acid. 63Ni activity was measured with a liquid scintillation spectrometer, and the chemical yields were controlled by means of AAS method. A significant correlation between 60Co and 63Ni was found for both sets of samples, and the 63Ni/60Co mean ratio (decay corrected) is comparable for the two sets of samples.

The results of the investigation of (239+240)Pu, 241Am and thorium isotope activity concentrations in bones of wild herbivorous animals (deer, roe-deer, boars, elks) from north-eastern Poland are presented. The area on which the animals were living had relatively high Chernobyl plutonium fallout. Possible traces of plutonium were seen only in four samples, but only for one it was it 3sigma above background, at 6.2 +/- 2.4 mBq/kg (ash). The 241Am activity concentration was below the detection limits in all samples. The maximum 228Th concentration in the samples was 7.81 +/- 0.44 Bq/kg (ash), calculated under the assumption of 100% thorium recovery. This isotope seems to originate in bones not from direct incorporation but from the decay of 228Ra. Large variations in activity concentration wose observed, as well as some differences between boars and the chewing animals.

Samples belonging to two species of lichen and one of moss collected on the Antarctic seashore (King George Island, Deception, Antarctic Peninsula) were analysed for gamma-emitters using HPGe gamma-spectrometry, and for alpha-emitters using alpha-spectrometry with silicon detectors. Observed 137Cs activities show large variations: from 4.1±0.4 to 74±3 Bq/kg. Total activity of 210Pb changed from

Described are results and the procedure for a pilot study on 237Np content in forest litter samples from Poland in relation to their plutonium activity. Neptunium was determined by inductively coupled plasma mass spectrometry (ICP-MS) and Pu by alpha spectrometry. Two samples originated from a location with pure global fallout and two others from a place with about 65% of the plutonium from Chernobyl. Plutonium activities were determined twice: at Krakow and in Monaco. The two results were consistent and 239 + 240Pu activities ranged from about 1 to about 7 Bq/kg dry weight (dw). The chemical recovery for Np was between 27 and 89%. Results for 237Np activity concentrations were between 0.099 ± 0.005 and 2.21 ± 0.076 mBq/kg dw. Observed activity ratios were lower than expected and could be explained by fractionation of Np against Pu in forest litter.

The appearance of plutonium isotopes in the environment was connected with the human activity, mainly: nuclear weapon tests (global fallout), nuclear accident in Chernobyl (1986), disintegration of satellite SNAP 9 (1963) and releases from nuclear reprocessing factories. At present, the concentration of plutonium in the atmosphere is very small but still observable. The aim of the study is to report and to discuss the results of plutonium alpha-emitters determination from sampling aerosols in air (Krakow 1990–1998, 2001–2002 and Bialystok 1996–1998, 2001) and in precipitation (Krakow 2005–2006). Plutonium activity concentration in air samples (in Krakow and Bialystok) varied in range: 0.22±0.04 nBq/m3 to 17.1±1.3 nBq/m3 for 239+240Pu and 0.033±0.018 nBq/m3 to 2.54±0.22 nBq/m3 for 238Pu and deposition of atmospheric precipitation (Krakow): from 0.041±0.011 mBq/m2 to 2.81±0.24 mBq/m2 for 239+240Pu and for 238Pu below 1.29±0.45 mBq/m2. One of the mechanisms responsible for the airborne plutonium is resuspension but on the other hand the main source of plutonium in the air seems to be marines aerosols from North See. This new hypothesis will be checked during the future research. The most interesting finding is the seasonal variation of plutonium air concentration. The conclusion from calculated ratio of plutonium isotopes (238Pu/239+240Pu) is that they are usually not typical for the global fallout.

Twenty seven samples of forest litter or humus layers ( A 0 or A 1 ) collected in 1991 in selected regions of Poland were analysed for the presence of 241 Am, Cm isotopes and rare-earth alpha-emitters. Samples were originating from a large research project and were previously analysed for gamma-emitters and plutonium. The measurements were done using alpha spectrometry preceded by a radiochemical separation procedure. Additional low-level gamma spectrometric measurements were performed for the rare-earths fractions of samples with the aim to search for europium gamma-emitters. The applied radiochemical procedure, based on the IAEA recommendations, is described. The maximum observed specific activity of 241 Am was found to be equal to (5.00 ± 0.19) Bq/kg, for 243+244 Cm it was (0.25 ± 0.02) Bq/kg and for 147 Sm it was (0.124 ± 0.009) Bq/kg. The possible origin of each isotope is discussed. The obtained results confirmed the presence of the non-volatile isotopes of the Chernobyl fallout in north-eastern Poland.

A low background gamma spectrometer with an Etruscan, 2500 years old lead shield and a muon veto detector were applied to study 22Na and 7Be activity concentration in ground level air aerosol samples collected weekly over the years 2003–2006 in Kraków. Each sample was formed with ca 100 000 m3 of passed air, collected with two parallel ASS-500 high volume air samplers. The results for 40K and 137Cs are also presented for reference and comparison. Presented frequency distributions for activity concentration and correlation between the obtained results are discussed. The activity concentration results confirmed seasonal variation of activity to be different for all the investigated radionuclides. Moreover, the seasonal variation in nucleus activity ratio was also noticed for 22Na and 7Be. Cosmogenic radionuclides being mainly of stratospheric origin, are subsequently attached to fine aerosols, via which they are transported to the ground level air. The mean aerosol transport time within the troposphere was estimated as equal to 7.5 days on average, reaching even 50 days in warm seasons. Limitations of the applied model were identified.

The paper presents the results of our study on 238Pu, 239Pu, 240Pu, 241Am and 90Sr concentration in human bones carried out on a set of 88 individual samples of central Europe origin. Bone tissue samples were retrieved under surgery while introducing hip joint implants. The conducted surgeries tend to cover either southern or northeastern parts of Poland. While for the southern samples only global fallout was expected to be seen, a mixed global and Chernobyl fallout were to be reflected in the others. Alpha spectrometry was applied to obtain activity concentration for 238Pu, 239+240Pu, 241Am, while liquid scintillation spectrometry for 90Sr and mass spectrometry to receive 240Pu/239Pu mass ratio. Surprisingly enough, and to the contrary to our expectations we could not see any significant differences in either Pu activity or Pu mass ratio between the studied populations. In both populations Chernobyl fraction proved marginal. The results on 90Sr and 241Am confirm similarities between the two examined groups.

The method applied in a programme for the investigation of radioactive contamination in forests of Poland is presented. The method is discussed in three parts: sampling, calibration of the spectrometers, and presentation of the results.

Samples of coniferous forest litter collected in POland, of known γ-emitters activity, have been analysed for α emitting plutonium isotopes. Specific as well as surface activities of the samples have been determined. Chernobyl and global fallout components have been distinguished for each sample. The observed maximum surface activity for Chernobyl fallout is above 25 Bq m−2 (for all α-emitting Pu isotopes), and up to 30% of expected global fallout values are also present in some samples. Chernobyl component is well correlated with the previously determined 144Ce activity, which supports the model of small fuel-like hot particles precipitation. The radiochemical procedure and the method of analysis of spectra are described. Dosimetric interpretation of the results is presented.

The results of a 5-year investigation on the radioactive contamination of mushrooms are presented. More than 400 samples of various mushrooms species have been examined for γ-emitters. Some samples have also been analysed for strontium-90 and plutonium isotope content. Maps of caesium-137, caesium-134 and potassium-40 activities, based on the measurements of 278 samples of Xerocomus badius collected in 1991 throughout Poland are presented. The highest measured activity of caesium-137 was 157 kBq/kg dry mass ( Xerocomus badius ). A dosimetric interpretation of the observed contamination levels is proposed.

Radioactive emissions into the atmosphere from the damaged reactors of the Fukushima Dai-ichi nuclear power plant (NPP) started on March 12th, 2011. Among the various radionuclides released, iodine-131 ( 131I) and cesium isotopes ( 137Cs and 134Cs) were transported across the Pacific toward the North American continent and reached Europe despite dispersion and washout along the route of the contaminated air masses. In Europe, the first signs of the releases were detected 7 days later while the first peak of activity level was observed between March 28th and March 30th. Time variations over a 20-day period and spatial variations across more than 150 sampling locations in Europe made it possible to characterize the contaminated air masses. After the Chernobyl accident, only a few measurements of the gaseous 131I fraction were conducted compared to the number of measurements for the particulate fraction. Several studies had already pointed out the importance of the gaseous 131I and the large underestimation of the total 131I airborne activity level, and subsequent calculations of inhalation dose, if neglected. The measurements made across Europe following the releases from the Fukushima NPP reactors have provided a significant amount of new data on the ratio of the gaseous 131I fraction to total 131I, both on a spatial scale and its temporal variation. It can be pointed out that during the Fukushima event, the 134Cs to 137Cs ratio proved to be different from that observed after the Chernobyl accident. The data set provided in this paper is the most comprehensive survey of the main relevant airborne radionuclides from the Fukushima reactors, measured across Europe. A rough estimate of the total 131I inventory that has passed over Europe during this period was \textless1% of the released amount. According to the measurements, airborne activity levels remain of no concern for public health in Europe. © 2011 American Chemical Society.

Strontium-90, plutonium and americium activity concentrations in a few samples of forest soils, some species of mushrooms and fern leaves have been determined. These results are compared with cesium activity concentrations in the same materials obtained in a previous work. Radiochemical procedures are described. The origin of the contamination (Chernobyl accident or nuclear test explosion release) is discussed. The90Sr activity concentration ranges from 0.6 Bq/kg (mushroom samples) to 48.4 Bq/kg (fern leaves). For239+240Pu, it ranges from not detected above background (mushrooms, fern) to 10.8 Bq/kg (humus layer of forest soil). The maximum concentration of241Am is found to be 2.4 Bq/kg (humus sample) and for238Pu it is 0.85 Bq/kg (also in the humus sample).

The paper presents a new sampling method for studying in-body radioactive contamination by bone-seeking radionuclides such as (90)Sr, (239+240)Pu, (238)Pu, (241)Am and selected gamma-emitters, in human bones. The presented results were obtained for samples retrieved from routine surgeries, namely knee or hip joints replacements with implants, performed on individuals from Southern Poland. This allowed to collect representative sets of general public samples. The applied analytical radiochemical procedure for bone matrix is described in details. Due to low concentrations of (238)Pu the ratio of Pu isotopes which might be used for Pu source identification is obtained only as upper limits other then global fallout (for example Chernobyl) origin of Pu. Calculated concentrations of radioisotopes are comparable to the existing data from post-mortem studies on human bones retrieved from autopsy or exhumations. Human bones removed during knee or hip joint surgery provide a simple and ethical way for obtaining samples for plutonium, americium and (90)Sr in-body contamination studies in general public.

Experimental data of caesium and ruthenium radioactivity in chosen parts of forest ecosystems in Finland and Southern Poland are presented and compared. Measurements were performed with a low-background γ-spectrometer coupled with a Ge/Li/ detector. The maximum caesium-137 activity in litter from Poland is 2.5 kBq, in that from Finland 3.9 kBq, in spruce needles it is 0.4 kBq /Poland/, 0.9 kBq /Finland/ and in fern leaves it is as high as 15.9 kBq per kg of dry mass in one sample from Poland.

We present here measurements of the 131I concentration for both: gaseous and aerosol fraction of 131I in the air above the septic tank containing wastes from medical application of this isotope. Aerosols were collected using air filters, whereas gaseous forms of iodine were trapped in KI impregnated charcoal double layer cartridge. Besides an active method (pumping of the air through system of filters) an attempt for using a passive method (charcoal traps) for monitoring of radio-iodine is described. For better characterisation of a site the external kerma was determined by means of G-M and TLD techniques as well as the activity kept in the septic tank was measured by gamma spectrometry. Results show that the activity of the aerosol fraction can be neglected compared to that of the gaseous fraction. He measured activity of air is low, on the level of 1 Bq m(-3), even during simulated failure of the ventilation system. Estimated inhalation dose for the serviceman of septic tanks is low ( approximately 10%) compared with external dose obtained by such person due to gamma radiation from the tank (on the level approximately 500 nSv h(-1)). Therefore, the concept of passive monitoring of the iodine in air was abandoned. Also estimated is the efficiency of 131I reduction by a charcoal filter of the ventilation system and 131I input to the environment by the ventilation chimney.

Publisher Summary In a survey performed to estimate the presence of DU in regions where DU ammunition had been deployed, no clear evidence of its presence in the local environment or in the bodies of local inhabitants was observed, except in samples that came into direct or very close contact with DU penetrators. The activity ratios of particular interest ( 235 U to 238 U and 234 U to 238 U) in general tend to show typical values observed in the natural environment. The only environmental sample analyzed by alpha spectrometry to show an abnormal activity ratio suggesting the presence of DU was a piece of scrap metal covered with dust. This may have been an element of military equipment that had been fired at with DU armor-piercing ammunition. Samples of dust collected on air filters were too small to obtain conclusive results. Large volume air samplers should be used in the future to study the environmental pathways of DU over longer time periods.

We have constructed and operated the ICARUS T600 liquid argon (LAr) time projection chamber (TPC). The ICARUS T600 detector is the largest LAr TPC ever built, with a size of about 500 tons of fully imaging mass. The design and assembly of the detector relied on industrial support and represents the applications of concepts matured in laboratory tests to the kton scale. The ICARUS T600 was commissioned for a technical run that lasted about 3 months. During this period all the detector features were extensively tested with an exposure to cosmic-rays at surface with a resulting data collection of about 30000 events. The detector was developed as the first element of a modular design. Thanks to the concept of modularity, it will be possible to realize a detector with several ktons active mass, to act as an observatory for astroparticle and neutrino physics at the Gran Sasso Underground Laboratory and a second-generation nucleon decay experiment. In this paper a description of the ICARUS T600 is given, detailing its design specifications, assembly procedures and acceptance tests. Commissioning procedures and results of the technical run are also reported, as well as results from the off-line event reconstruction. (C) 2004 Elsevier B.V. All rights reserved.

Adults of the geotrupine beetle Anoplotrupes stercorosus (Coleoptera, Geotrupidae), a common European forest insect species, were used in the role of bio-monitors for mainly man-made radionuclides in a forest environment. Activities of 137Cs, 40K, 238Pu, (239+240)Pu, 90Sr and 241Am were studied. Samples originated from four areas in Poland, two from the north-east and two from the south of the country. The north-eastern areas were previously recognized as the places where hot particle fallout from Chernobyl took place. Results confirmed the differences in the activities between north-eastern and southern locations. Significant correlations were found between activities of 40K and 137Cs, and between activities of plutonium and americium isotopes. An additional study of the concentration of radionuclides within the bodies of beetles showed a general pattern of distribution of radioisotopes in the insect body.

Plutonium in Polish forest soils and the Bór za Lasem peat bog is resolved between Chernobyl and global fallout contributions via inductively coupled plasma mass spectrometric measurements of 240Pu/230Pu and 241Pu/239Pu atom ratios in previously prepared NdF3 alpha spectrometric sources. Compared to global fallout, Chernobyl Pu exhibits higher abundances of 240Pu and 241Pu. The ratios 240Pu/230Pu and 241Pu/239Pu co-vary and range from 0.186 to 0.348 and 0.0029 to 0.0412, respectively, in forest soils (241Pu/239Pu = 0.2407 x [240Pu/239Pu] - 0.0413; r2 = 0.9924). Two-component mixing models are developed to apportion 239+240Pu and 241Pu activities; various estimates of the percentage of Chernobyl-derived 239+240Pu activity in forest soils range from10% to90% for the sample set. The 240Pu/230Pu - 241Pu/239Pu atom ratio mixing line extrapolates to estimate 241Pu/239Pu and the 241Pu/239+240Pu activity ratio for the Chernobyl source term (0.123 +/- 0.0007; 83 +/- 5; 1 May 1986). Sample 241Pu activities, calculated using existing alpha spectrometric 239+240Pu activities, and the 240Pu/230Pu and 241Pu/239Pu atom ratios, agree relatively well with previous liquid scintillation spectrometry measurements. Chernobyl Pu is most evident in locations from northeastern Poland. The 241Pu activities and/or the 241Pu/239Pu atom ratios are more sensitive than 240Pu/239Pu or 238Pu/239+240Pu activity ratios at detecting small Chernobyl 239+240Pu inputs, found in southern Poland. The mass spectrometric data show that the 241Pu activity is 40-62% Chernobyl-derived in southern Poland, and 58-96% Chernobyl in northeastern Poland. The Bór za Lasem peat bog (49.42 degrees N, 19.75 degrees E), located in the Orawsko-Nowotarska valley of southern Poland, consists of global fallout Pu.

The paper presents results on Pu, U and Th isotope activity concentration measurements in some mushroom samples collected in Poland, Spain and Ukraine. The sampling sites differ a lot with regard to observed levels of Pu, its origin and isotope ratios as well as the environmental properties. Some of the Polish samples were collected in the northeastern part of the country with up to 30 Bq/m2 of Chernobyl Pu deposition. Other Polish and the Spanish samples are from areas with almost exclusively global fallout Pu present. Ukrainian samples were collected in a highly contaminated area with a deposition of about 3.7 kBq/m2 of Chernobyl (239-240)Pu. The maximum (239+240)Pu activity concentration was found equal to (54+/-4) Bq/kg (dw--dry weight) for a Ukrainian Cantharellus cibarius sample. Ukrainian samples have an extremely high radiocesium level, with maximum of (51+/-4) MBq/kg (dw). The maximum (239+240)Pu activity concentration for Polish samples was (81+/-5) mBq/kg (dw) for Xerocomus badius. From the isotopic ratio in this sample it can be concluded that Chernobyl fallout is the origin of Pu. More than twice as large was the Spanish maximum for Hebeloma cylindrosporum but with only global fallout Pu. Some aspects of the transfer of nuclides to fruit bodies is discussed and in some cases the transfer factors or aggregation coefficients were calculated. Especially high transfer factors were found for Hebeloma cylindrosporum from Spain.

Bor za Lasem is a raised bog in the Orawsko-Nowotarska Valley (southern Poland). About half of the Bor za Lasem area has been exploited while the rest is undisturbed. Peat samples from both parts of the bog were analysed. Measurements of 137Cs, 134Cs, 239,240Pu, 238Pu ,40K, 228Ra, and 226Ra activity concentrations in all samples were performed. Comparison of the results of radiocaesium and plutonium activity concentrations reveals the highest activity concentrations of radionuclides in the undisturbed part of the peat-bog area. The radiocaesium content decreased with depth, whereas the plutonium concentration had a maximum value at a depth of 15–20 cm. The lowest activity concentrations were found in the exploited part of the bog. Potassium and radium isotopes were detected only in shallow openings within the heavily exploited part of the bog, which might suggest partial mixing of the peat with the mineral sub-soil. The growth rate of the top layer of the undisturbed part of the bog obtained from plutonium distribution was estimated as approximately 0.5 cm per year.

Results of studies conducted during the nineties in Poland on plutonium in the environment are presented. Four laboratories were involved in the analyses of soils from different locations and types, including forest litter, peat, river and sea sediments, mosses, lichens, mushrooms, animal bones, aerosols from ground-level air, rain water, food products of the average diet, sea water and marine biota including fish. Samples were collected in the territory of Poland and in the Baltic Sea in the Polish economic zone. Ranges or only maximum observed activities are presented. The investigations were conducted mostly to estimate the influence of the Chernobyl accident on the present plutonium burden in the environment of Poland. The fallout pattern was reconstructed to study the plutonium inventory. The maximum inventory of global fallout plutonium was found in one sample of Baltic Sea sediment (314 Bq/m 2 ). The maximum inventory of Chernobyl fallout plutonium was found in the far north-east of Poland. It was 25 Bq/m 2 for plutonium alpha-emitters and 1.025 kBq/m 2 for 241 Pu. A difference in the behaviour of plutonium between global and Chernobyl fallout was noticed. The committed dose equivalent for a person exposed to Chemobyl-origin aerosols and to ingestion intake of plutonium from foodstuffs was calculated. The inhalation committed equivalent dose was estimated to be significantly higher than that from ingestion. However, both were considered low and did not exceed 0.1 mSv.

241 Pu activity measurements in coniferous forest soil samples from Poland are presented. The results were obtained in two ways: by alpha spectrometric remeasurements of the plutonium sources 3–4 years after their preparation (i.e. by the 241 Am ingrowth) and by direct measurements of 241 Pu using liquid scintillation (LS) spectrometry. Both methods gave consistent results. The maximum observed activity concentration obtained by the 241 Am ingrowth was (254±43) Bq/kg, and by direct measurements it was (284±31) Bq/kg (the same sample, activities calculated for May 1, 1986). Enhanced levels of 241 Pu were observed in all samples from the farthest north-eastern Poland. The estimated 241 Pu maximum deposition from Chernobyl fallout in this area (sum of deposition for two examined layers of one site) was (1.025±0.110) kBq/m2. This will result after 70 years in an additional 241 Am activity of about (30.1±3.2) Bq/m2. The average ratio for 241 Pu to total 238,239,240 Pu was of the order of 25. The obtained average Chernobyl ratios for 241 Pu to 239,240 Pu were about 86, and those for 241 Pu to 238,239,240 Pu were 56.

It has been found that in skull bones of small mammals have significantly higher Pu and Am concentrations than ever found in bones of any other species in areas contaminated by global fallout. Since there was no difference between skulls of rodents and insectivorous, an explanation is proposed that the contamination takes place by the inhalation of Pu and Am tiny soil particles.

Partial results of a large survey of radioactive contamination in Polish forests are presented. All measurements were performed with low-background γ spectrometers. The measurement method is briefly described. Activities of 137Cs 134Cs 125Sb 106Ru, 144Ce 154Eu 155Eu, and 60Co in A0 and A1 layers of forest litter from all over Poland are determined. The geographical distribution of contamination as well as its origin is discussed. Nonuniform composition of the Chernobyl fallout over Poland is confirmed and documented.

The aim of this work was to check whether the stable cesium content in forest litter affects the value of radiocesium from litter-tomushroom transfer factor Tf or not. Total cesium in litter, measured by AAS, varied from 0.1–2.7 pg/g. These data, combined with earlier results for mushrooms, showed no simple correlation for Tf. More complex relationships provided very high correlation coefficients, but their validity needs further investigation.

The influence of arbuscular mycorrhizal fungus on 134Cs uptake by Helianthus annuus was studied in a pilot study under growth chamber conditions. Mycorrhizal plants took up five times more 134Cs (up to 250,000 Bq kg-1 dry weight) than non mycorrhizal plants. Silver and titanium nanoparticles, supplied into the surface soil layer decreased both the mycorrhizal colonization and Cs uptake by mycorrhizal plants. The application of activated carbon attenuated the effect of nanoparticles and increased 134Cs uptake in the presence of mycorrhizal fungi (up to 400,000 Bq kg-1 dry weight). The results underline the possible application of phytoremediation techniques based on mycorrhiza assisted plants in decontamination of both radionuclides and nanoparticles. Se estudió mediante una prueba piloto en una cámara de crecimiento la influencia de hongos formadores de micorrizas arbusculares en la captación de 134Cs por Helianthus annuus. Las plantas micorrizadas incrementaron hasta cinco veces la captación de 134Cs (hasta 250.000 Bq kg-1 peso seco). La adición de nanopartículas de plata y titanio en la superficie del suelo disminuyó tanto la colonización del hongo como la captación de 134Cs en las plantas micorrizadas. La aplicación de carbón activado atenuó el efecto de las nanopartículas e incrementó la captación de 134Cs en presencia de hongos micorrízicos (hasta 400.000 Bq kg-1 peso seco). Los resultados sugieren una posible aplicación de plantas micorrizadas en técnicas de fitorremediación para la recuperación de suelos contaminados con radionucleotidos y nanopartículas.

Spektrometria promieniowania γ należy do jednej z najbardziej rozpowszechnionych technik spektrometrii promieniowania jonizującego i znajduje zastosowanie w różnych dziedzinach nauki, przemysłu oraz medycyny. Uniwersalność tej techniki przejawia się w możliwości badania obiektów charakteryzujących się zarówno niskimi jak i wysokimi aktywnościami izotopów promieniotwórczych emitujących kwanty γ z szerokiego spektrum energetycznego. W przypadku badań materiałów o niskich aktywnościach radionuklidów (np. na potrzeby badań środowiskowych), kluczowe staje się osiąganie odpowiednio niskich limitów detekcji, umożliwiających oznaczenie szukanych izotopów promieniotwórczych obecnych w mierzonych próbkach. Cel ten osiągany jest m.in. poprzez zastosowanie odpowiednich detektorów, elektroniki spektrometrycznej, jak również specjalnie skonstruowanych osłon - pasywnych oraz aktywnych. Głównymi celami niniejszej rozprawy było skonstruowanie niskotłowego, cyfrowego spektrometru promieniowania gamma, oraz stworzenie oprogramowania służącego do analizy generowanych danych pomiarowych. Następnie, wykorzystując przygotowanie stanowisko badawcze, wykonano serię pomiarów wyselekcjonowanych próbek charakteryzujących się niskimi aktywnościami radioizotopów. Ponadto, w wyniku zastosowania cyfrowego systemu akwizycji danych, możliwym stało się rozszerzenie potencjału badawczego spektrometru promieniowania gamma, poprzez zastosowanie wielorakiej eksploracji gromadzonych danych pomiarowych, co pozwoliło na zapoczątkowanie monitoringu intensywności strumienia mionów promieniowania kosmicznego, rejestrowanego przez detektory osłony aktywnej spektrometru., Gamma-ray spectrometry is one of the most widespread ionizing radiation spectrometry technique and it finds application in various fields of science, industry and medicine. The versatility of this technique manifests itself in the possibility of testing objects characterized by both low and high radionuclides’ activities and emitting γ quanta from the wide range of energy spectrum. In the case of measurements of low-radioactive materials (e.g. in the field of environmental research), it is crucial to achieve sufficiently low detection limits in order to identify radioactive isotopes present in measured samples. This goal is achieved, among others, through the utilization of appropriate detectors, signal processing electronics as well as specially constructed shields - both passive and active. The main goals of this dissertation were construction of a low-background, digital gamma - ray spectrometer and development of purposely written software for analyzing generated measurement data. Then, utilizing set up scientific device, a series of measurements of selected samples characterized by low radioisotopes’ activities were performed. In addition, as a result of utilization of a digital data acquisition system, it has become possible to expand the research potential of the gamma - ray spectrometer, by using manifold ways of exploration of collected measurement data, what allowed to initiate monitoring of cosmic-ray muons flux registered by active shield’s detectors., 239