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Abstract: After the closure of the former Žirovski Vrh uranium mine in Slovenia, mining and milling wastes were deposited on two waste piles, which are located close to the mine. These wastes contain elevated levels of natural radionuclides from the uranium decay chain. Due to different migration processes (erosion, aerial deposition, through groundwater), these radionuclides can be transported via fodder into cow’s milk, which is an important foodstuff for Slovenian people. Therefore, natural radionuclides were analysed in the transfer food chain from soil to cow’s fodder and cow’s milk. After sampling, 238U, 234U, 230Th, 226Ra, 210Pb and 210Po were determined using radiochemical separation methods and alpha spectrometry or proportional counting. Hay and silage to milk concentration ratios (kg dry weight L−1) were calculated and were 0.260 for 238U, 0.255 for 230Th, 0.070 for 226Ra, 0.021 for 210Pb and 0.019 for 210Po. The calculated annual ingestion dose due to milk consumption for the natural radionuclides analysed was 9 μSv/year for adults and 389 μSv/year for infants with the highest contribution of 210Po (51% for adults and 63% for infants) and 210Pb (36% for adults and 24% for infants). This study provides new data quantifying the transfer of natural radionuclides to milk, which is a parameter for which there have been very few previously reported values. [Copyright &y& Elsevier]

Abstract: As a result of former uranium mining and milling activities at Žirovski vrh, Slovenia, 0.6 million tons of uranium mill tailings (UMT) were deposited onto a nearby waste pile Boršt. Resulting enhanced levels of natural radionuclides in UMT could pose threat for the surrounding environment. Therefore, sequential extraction protocol was performed to assess mobility and bioavailability of 238U, 234U, 230Th and 226Ra in soils from the waste pile and its surrounding. The radionuclides associated with exchangeable, organic, carbonate, Fe/Mn oxides and residual fraction, respectively, were determined. Results showed that the highest activity concentrations for the studied radionuclides were on the bottom of the waste pile. In non-contaminated locations, about 80% of all radionuclides were in the residual fraction. Considering activity concentrations in the UMT, 238U and 234U are the most mobile. Mobility of 226Ra is suppressed by high sulphate concentrations and is similar to mobility of 230Th. [Copyright &y& Elsevier]

Abstract: Activity concentrations of 234U, 238U, 226Ra, 228Ra, 210Po and 210Pb in all Croatian bottled drinking natural spring and natural mineral water products, commercially available on the market, were determined. The samples originated from various geological regions of Croatia. Activity concentrations of measured radionuclides are in general decreasing in this order: 234U> 238U> 226Ra> 228Ra> 210Pb> 210Po and 226Ra> 228Ra> 234U> 238U> 210Pb> 210Po for natural spring and mineral waters, respectively. Based on the radionuclide activity concentrations average total annual effective ingestion doses for infants, children and adults, as well as contribution of each particular radionuclide to total dose, were assessed and discussed. The highest doses were calculated for children from 7 to 12years of age, which makes them the most critical group of population. All values for each type of water, as well as for each population group, were well below the recommended reference dose level (RDL) of 0.1mSv from one year''s consumption of drinking water according to the European Commission recommendations from 1998. Contribution of each particular radionuclide to total doses varied among different water types and within each water type, as well as between different age groups, where the lowest contribution was found for uranium isotopes and the highest for 228Ra. [Copyright &y& Elsevier]