[en] The Province of Salzburg is one of the regions with the highest contamination due to the Chernobyl fallout in western Europe. The average value of the accumulated ¹³⁷Cs deposition has been determined to be 70 kBq/m² in flat land and on valley floors and 105 kBq/m² on Alpine pastures. The results of measurements continuing since the reactor accident have shown that the soil to vegetation transfer factors vary by at least one order of magnitude. The region with the highest transfer factors and consequently highest contamination in milk and dairy products is mainly restricted to pasture land of the mountain region along the southern border of the Province of Salzburg north of the highest elevations in the Alps. Taking into consideration geological and geographical conditions appears to lead to a better general estimation of the expected ¹³⁷Cs levels of locally produced food in contaminated areas. (author). 9 refs, 10 figs, 1 tab

[en] Short communication

[en] The Province of Salzburg and adjacent parts of Upper-Austria belong to the regions with the highest contamination from the Chernobyl-Fallout outside the former CIS. The range of the specific ¹³⁷Cs contamination varies between 10 kBq/m² and 80 kBq/m² in April 1986 due to locally different meteorological conditions at the time of the passage of the radioactive cloud. The highest contaminated regions in geographic terms are at the northern flank of the Alps and the northern parts of the Hohe Tauern region. Besides the systematic variation of the contamination on a regional scale a random inhomogeneity of the fallout on a smaller scale (100 m² up to 10,000 m²) could be found. For the quantitative analysis of the small scale-inhomogeneities a systematic investigation of the fallout on a test-site of 10,000 m² in the City of Salzburg was conducted by sampling 235 soil samples and statistical analysis of the measurement results. The data of the soil samples, together with the statistical analysis, offer a possibility for the estimation of the uncertainties associated with the calculation of the specific contamination, derived from soil sample data. The contamination map of the Province of Salzburg and of the adjacent parts of Upper-Austria was derived from results of soil-sample measurements and the evaluation of in-situ spectra measured at altogether 41 sampling sites. The method of using the experimentally measured depth-distribution for evaluating the in-situ spectra was applied for the calculation of the surface-contamination. The depth distributions found on the different sites can be correlated with the different soil types. (author, shortened by E.B.)

[en] Namibia, situated in south-western Africa, has a population of about 1.2 million living in an area of 824,000 km² with a rather heterogeneous geology. Metasediments of the Damara Group are the dominating geological units, interspersed with coarse sandstone, siltstone, greywackes and marls, with locally enriched uranium content. Since the population is predominantly occupied in outdoor activities, such as agriculture and open-pit mining, the exposure outdoors is of significance for the total dose from the natural radiation environment (NRE). In this large-scale radiometric land survey over a distance of 4000 km external dose rate outdoors and indoors were determined, together with measurements of ²³⁸U, ²³²Th, ²²⁶Ra and ⁴⁰K in soil samples. The results show that generally the NRE of Namibia is characterised by relatively small variations of environmental radioactivity, ranging from 0.09 to 0.18 μGy.h^-1 outdoors and from 0.11 to 0.19 μGy.h^-1 indoors. Variations of the dose rate outdoors and indoors are presented as a map and as a histogram respectively. (author)

[en] Abstract only

[en] On glacier surfaces sediments accumulate as so-called cryoconites in small depressions, ice pockets, crevasses, along ablation edges etc. Cryoconite is generally very fine-grained and therefore able to efficiently adsorb pollutants. In samples from glaciers we found ¹³⁷Cs activity concentrations between 255 and 136000 Bq/kg d.m. Contribution of global fallout ¹³⁷Cs is between 0 and 65 % of total ¹³⁷Cs. Further anthropogenic radionuclides detected are ⁹⁰Sr, ^238,239,240Pu, ²⁴¹Am, ¹²⁵Sb, ¹⁵⁴Eu, ⁶⁰Co and ^94gNb. The composition of the radionuclides which can be attributed to Chernobyl appears to be the same as in original fallout, indicating that no chemical fractionation takes place between fallout and cryoconite. The spatial variability of radionuclide concentrations in cryoconites is very high. We discuss the possible role of cryoconites as present and future sources of radionuclide releases into the biosphere. (author)

[en] Published in summary form only

[en] The existing database on thoron (Tn) in the environment, the experimental validation of dosimetric models and potential health effects are scarce. Available information on Tn and its decay products (Tn-d) indoors and outdoors is associated with partly significant uncertainties due to methodological shortcomings. Dosimetric modelling reveals that ThB (²¹²Pb) data are to be considered as the most important input parameter. Under typical indoor exposure conditions the dose due to Tn-d is about one order of magnitude less than from radon decay products (Rn-d). However, special circumstances have been identified where the Tn-d dose contribution can exceed the corresponding Rn-d values. Several health effects have been associated with elevated exposure among workers in thoron-related industries and residents in high thoron background areas. (Author)

No abstract available

[en] Short communication