Inter-cultivar variation in soil-to-plant transfer of radiocaesium and radiostrontium in Brassica oleracea

Radiocaesium and radiostrontium enter the human food chain primarily via soil-plant transfer. However, uptake of these radionuclides can differ significantly within species (between cultivars). The aim of this study was to assess inter-cultivar variation in soil-to-plant transfer of radiocaesium and radiostrontium in a leafy crop species, Brassica oleracea. This study comprised four independent experiments: two pot experiments in a controlled environment artificially contaminated with radiocaesium, and two field experiments in an area contaminated with radiocaesium and radiostrontium in the Chernobyl Exclusion Zone. Radiocaesium concentration ratios varied 35-fold among 27 cultivars grown in pots in a controlled environment. These 27 cultivars were then grown with a further 44 and 43 other cultivars in the Chernobyl Exclusion Zone in 2003 and 2004, respectively. In the field-grown cultivars radiocaesium concentration ratios varied by up to 35-fold and radiostrontium concentration ratios varied by up to 23-fold.In three of these experiments (one pot experiment, two field experiments) one out of the 27 cultivars was found to have a consistently lower radiocaesium concentration ratio than the other cultivars. The two field experiments showed that, five out of the 66 cultivars common to both experiments had consistently lower radiocaesium concentration ratios, and two cultivars had consistently lower radiostrontium concentration ratios. One cultivar had consistently lower radiocaesium and radiostrontium concentration ratios.The identification of cultivars that have consistently lower radiocaesium and/or radiostrontium concentration ratios suggests that cultivar selection or substitution may be an effective remediation strategy in radiologically contaminated areas. Future research should focus on plant species that are known to be the largest contributors to human dose

Study of the premicellar state in aqueous solutions of sodium dodecyl sulfate by nuclear magnetic resonance diffusion

Self-diffusion coefficients of sodium dodecyl sulfate (SDS) were measured in aqueous solutions in the premicellar range of the SDS concentrations 7–34.7 mM and temperatures 30–90°C. Average effective hydrodynamic radii and aggregation numbers of SDS in the premicellar region were determined. At C CMC, the increase of temperature leads to decrease in the effective hydrodynamic radii and the average aggregation numbers. At C > > CMC, it is impossible to reach the monomeric state by increasing the temperature

The transfer of Cs-137 and Sr-90 to wild animals within the Chernobyl exclusion zone

More than 700 137Cs and 90Sr activity concentrations for the tissues of 8 species of mammals and 13 species of birds sampled from within the Chernobyl exclusion zone between 1988 and 2000 have been collated. These data present a useful contribution to the current development of environmental impact assessment approaches with regard to ionising radiation. Summarised transfer values are presented and discussed

The transfer of 137Cs and 90Sr to dairy cattle fed fresh herbage collected 3.5 km from the Chernobyl nuclear power plant

A study conducted during summer 1993 to determine the bioavailability and transfer of 137Cs and 90Sr to dairycattle from herbagecollected from a pasture contaminated by particulate fallout is described. The study pasture was located 3.5km from the Chernobyl nuclear powerplant. The true absorption coefficient (At) determined for 137Cs (0.23) was considerably lower than previous estimates for radiocaesium incorporated into vegetation by root uptake. It is likely that the low dry matter digestibility of the diet and the potential presence of 137Cs associated with adherent soil-associated fuel particles contributed to this low bioavailability. The At value determined for 90Sr (0.27) did not indicate a reduced bioavailability. It is suggested that the current and previous calcium status of the animals was the controlling influence on the transfer of 90Sr from the diet to mil

A case study in the Chernobyl zone Part I: Predicting radionuclide transfer to wildlife

A number of frameworks have been proposed to assess the protection of wildlife from ionising radiations. In this paper we compare the predictions of transfer parameters recommended by one of these frameworks (FASSET) with observed whole-body 90Sr and 137Cs activity concentrations in a range of mammal and invertebrate species sampled within the Chernobyl exclusion zone. Predicted activity concentrations are generally within the observed ranges and mean predictions for reference organisms are similar to, or circa one order of magnitude higher than, the observed means. However, some predictions are more than one order of magnitude lower than observed values. No data were available for animals to test predictions for the other radionuclides released by the Chernobyl accident. In a separate paper the outputs of this assessment will be used to estimate doses to reference organisms and compare these to observed radiation induced effects reported within the Chernobyl zone

Effectiveness of utilization of electric power in arc steelmaking furnaces with oxy-gas burners

Translated from Russian (Stal' 1986 (4) p. 39-40)Available from British Library Document Supply Centre- DSC:5828.4(M--36926)T / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo