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Evolution of radiocontamination in the Mediterranean Sea in the period 1985-1995
No full textInvestigations were carried out on several biotic and abiotic samples to determine the environmental radiocontamination of the Mediterranean Sea after the Chernobyl accident. Special emphasis was put on the determination of Cs-137 in the Adriatic Sea. This caesium isotope was the most abundant radionuclide in a wide variety of samples (seawater, sediment, pelagic and benthic species). Attention was also paid to the neutron activation products Ag-110m and Cs-134, which were first discovered in the Adriatic ecosystem after the Chernobyl event. In particular, although the Ag-110 fallout deposition over the area was negligible in comparison with that of Cs-137, its concentration factors and bioaccumulation in macroalgae and molluscs were much higher, suggesting some particular physiological accumulation mechanism. Concentrations of Sr-90, Pu-238 and Pu-239+240 were monitored in sediment samples collected in the period 1990-1993. A comparison of the radionuclide concentrations between the open sea area and the Po river estuarine ecosystem is also reported
A radioecological survey of Northern and Middle Adriatic Sea before and after the Chernobyl event (1979-1990).
No full textRadioecological research on the marine environment facing the italian base in antarctica (1989–91)
No full textThe results of the analysis of both natural (Th-232, U-238 and K-40) and artificial (Cs-137) radioactivity contained in samples collected during the 1989–90 and 1990–91 PNRA Scientific Campaigns in the Terra Nova Bay (Ross Sea) marine ecosystem, are presented in this paper. The data refers to samples of sea water, pack water, sediments and organisms belonging to demersal ichthyofauna (Pagothenia bemacchii, Chionodracohamatus) and soft bottom macrofauna (Adamussium colbecki) collected in different coastal and off shore stations of the area investigated. Some sea water samples collected on the way to sub Antarctic areas were also considered. The radiocontamination detected in sediments was correlated to the quantities of organic matter, organic carbon and nitrogen contained in the samples. Additionally, Cs-137 concentration factors were calculated for the different biological specimens and their anatomical components. Data values, with special consideration for anthropogenic Cs-137, are compared to results obtained from similar matrixes collected in the Northern Hemisphere in temperate waters before and after the accident at the Chernobyl nuclear plant. © 1994 Gordon and Breach Science Publishers S. A
Important alpha, beta and gamma - Emitting radionuclides in lichens and mosses collected in different world areas
No full textA radioecological survey was carried out in several world areas and different contamination levels were assessed through biological monitoring of the territory. In fact, concentrations of 90Sr, 134Cs, 137Cs and 239,240pu were detected in some species of lichens and mosses collected in Italy, Scandinavia, Nepal and Antartica during the period 1986 - 1993. Major differences were observed between areas strongly influenced by the Chernobyl accident and other ones coming from extreme environments (Antarctica and Nepal). The usefulness of these sensitive species in radioecological studies has been demonstrated through the determination of anthropogenic radionuclides in areas long considered as unpolluted sites. In particular, a good correlation between 137Cs and altitude was also determined in the 1993 Italian samples (Parma province)
Evolution of radiocontamination of the northern and middle Adriatic Sea in the period 1979-1990
No full textSeveral investigations were carried out on biotic and abiotic samples to determine the difference between Chernobyl and preChernobyl environmental radiocontamination of the Adriatic Sea. Special emphasis was put on the determination of 137Cs which resulted in the most abundant radionuclide in a wide variety of samples (sea water, sediment, pelagic and benthic species). Attention was also given to the neutron activation products 110mAg and 134Cs that were first discovered in the Adriatic ecosystem after the Chernobyl event. In particular, although the 110Ag fallout deposition over the area was neglected in comparison to that of 137Cs, its bioaccumulation in macroalgae and molluscs was much higher suggesting some particular physiological accumulation mechanism
Sr-90, Cs-137, Pu-238, Pu-239+240 and Am-241 levels in terrestrial and marine ecosystems around the Italian base in Antarctica (1987-2001)
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