A Note on 207Bi in Environmental Samples

Traces of the radionuclide 207Bi were identified in soil and cryoconite (glacier sediment) samples from Alpine regions of Austria. This nuclide has been produced in thermonuclear explosions mainly in the early 1960s and subsequently dispersed in the atmosphere. Activity concentrations up to 22 Bq/kg dry matter have been found. The ratio 207Bi : 137Cs (global fallout) equals (1.70 ± 0.12)10-3 , which is in accordance with literature data. When low levels of 207Bi are assessed by gamma spectrometry, corrections must be made for a gamma line produced in the lead shield by neutron activation due to cosmic neutrons. Keywords: 207Bi, global fallout, environmental radioactivity, gamma spectrometryJRC.H.4-Transport and air qualit

137Cs and 90Sr Transfer to Milk in Austrian Alpine Agriculture

The alpine regions of Austria were among the most contaminated territories outside of the former USSR after the Chernobyl accident. In the investigated province of Salzburg the median 137Cs surface deposition was 31.4 kBq m2 with maximum values exceeding 90 kBq m2 (May 1986). To quantify the transfer of 137Cs and 90Sr from vegetation to milk in these seminatural conditions nine seasonally grazed alps were identified and vegetation and milk sampled during summer 2002 and summer 2003. Mean SD milk transfer coefficients (fm) for 137Cs and 90Sr were 0.0071 0.0009 d l1, and 0.0011 0.0004 d l1, respectively; which for 137Cs is markedly higher than those fm values found in intensive agricultural systems. Transfer kinetics for 137Cs into cow milk were approximated using a 2-compartment model with a short and a long-term component. Fitting the model to empirical data results in reliable estimates of the time constant of the short-term component, biological half-life 1.06 0.28 d, whereas the estimates of the long-term component are subject to high uncertainties. 2007 Elsevier Ltd. All rights reserved.JRC.H.4-Transport and air qualit

Effects of Ultra-Weak Fractal Electromagnetic Signals on <i>Malassezia furfur</i>

Malassezia spp. are dimorphic, lipophilic fungi that are part of the normal human cutaneous commensal microbiome. However, under adverse conditions, these fungi can be involved in various cutaneous diseases. In this study, we analysed the effect of ultra-weak fractal electromagnetic (uwf-EMF) field exposure (12.6 nT covering 0.5 to 20 kHz) on the growth dynamics and invasiveness of M. furfur. The ability to modulate inflammation and innate immunity in normal human keratinocytes was also investigated. Using a microbiological assay, it was possible to demonstrate that, under the influence of uwf-EMF, the invasiveness of M. furfur was drastically reduced (d = 2.456, p p = 0.390) and with (d = 0.118, p = 0.438) uwf-EM exposure, were hardly affected. Real-time PCR analysis demonstrated that a uwf-EMF exposure is able to modulate human-β-defensin-2 (hBD-2) in treated keratinocytes and at the same time reduce the expression of proinflammatory cytokines in human keratinocytes. The findings suggest that the underlying principle of action is hormetic in nature and that this method might be an adjunctive therapeutic tool to modulate the inflammatory properties of Malassezia in related cutaneous diseases. The underlying principle of action becomes understandable by means of quantum electrodynamics (QED). Given that living systems consist mainly of water and within the framework of QED, this water, as a biphasic system, provides the basis for electromagnetic coupling. The oscillatory properties of water dipoles modulated by weak electromagnetic stimuli not only affect biochemical processes, but also pave the way for a more general understanding of the observed nonthermal effects in biota

Activity Ratios of 137Cs, 90Sr and 239/240Pu in Environmental Samples

Both global and Chernobyl fallout have resulted in environmental contamination with radionuclides such as 137Cs, 90Sr and 239þ240Pu. In environmental samples, 137Cs and 239þ240Pu can be divided into the contributions of either source, if also the isotopes 134Cs and 238Pu are measurable, based on the known isotopic ratios in global and Chernobyl fallout. No analogous method is available for 90Sr. The activity ratios of Sr to Cs and Pu, respectively, are known for the actual fallout mainly from air filter measurements; but due to the high mobility of Sr in the environment, compared to Cs and Pu, these ratios generally do not hold for the inventory many years after deposition. In this paper we suggest a method to identify the mean contributions of global and Chernobyl fallout to total Sr in soil, sediment and cryoconite samples from Alpine and pre-Alpine regions of Austria, based on a statistical evaluation of Sr/Cs/Pu radionuclide activity ratios. Results are given for Sr:Cs, Sr:Pu and Cs:Pu ratios. Comparison with fallout data shows a strong depletion of Sr against Cs and Pu.JRC.H.4-Transport and air qualit

Effective and Ecological Half-lives of 137Cs in Cow's Milk in Alpine Agriculture

Alpine regions have been heavily affected by the Chernobyl fallout depositing 137Cs activities up to more than 100 kBq/m². To a large extent, alpine ecosystems are semi-natural environments and vulnerable to radioactive contaminants with respect to their long persistence in the ecosystem. Since 1988 a continuous monitoring of 137Cs in milk on different seasonally used alpine production sites in Austria has been carried out and ecological half lives have been calculated. With good agreement the decrease of 137Cs in milk follows a simple exponential decay with ecological half-lives between approximately 6 y and 15 y depending on the site of the alpine pasture. However, from the decay curve of some sites there are good hints of more than one ecological half life controlling the decay and of a long lived component which may have an ecological half-life longer than 15 y. The differences are systematic and ecological half-lives are positively correlated with the altitude above sea level. Alpine sites on elevated altitudes show a marked tendency to longer ecological half-lives which corresponds with higher soil to plant transfer of 137Cs and lower migration rates in the soil.JRC.H.4-Transport and air qualit

Accumulation of Anthropogenic Radionuclides in Cryoconites on Alpine Glaciers

Cryoconites are airborne sediments which accumulate on the surface of glaciers. In samples of cryoconites a temperate Austrian glacier high activity concentrations of anthropogenic radionuclides were found, which stem from global and Chernobyl fallouts. Radionuclides identified were 137Cs, 134Cs, 238Pu, 239þ240Pu, 90Sr, 241Am, 60Co, 154Eu, 207Bi, and 125Sb. Given the approximately known isotopic ratios, Cs and Pu can be separated into the contributions of either source of origin. Published 137Cs/134Cs and 239þ240Pu/238Pu ratios were used for the discrimination of the Dachstein-glacier cryoconites according to their origin from global or Chernobyl fallout. Two different groups of cryoconites were identified, an older population dominated by nuclear weapons fallout and a younger one with predominant Chernobyl fallout. With those data a simple model was formulated to demonstrate the transition and mixing of these 2 populations on the glacier surface.JRC.DDG.H.4-Transport and air qualit

Real-time analysis of endogenous protoporphyrin IX fluorescence from δ-aminolevulinic acid and its derivatives reveals distinct time- and dose-dependent characteristics in vitro

Abstract. Photodynamic therapy (PDT) and photodiagnosis based on the intracellular production of the photosensitizer protoporphyrin IX (PPIX) by administration of its metabolic precursor δ-aminolevulinic acid (ALA) achieved their breakthrough upon the clinical approval of MAL (ALA methyl ester) and HAL (ALA hexyl ester). For newly developed ALA derivatives or application in new tumor types, in vitro determination of PPIX formation involves multiparametric experiments covering variable pro-drug concentrations, medium composition, time points of analysis, and cell type(s). This study uses a fluorescence microplate reader with a built-in temperature and atmosphere control to investigate the high-resolution long-term kinetics (72 h) of cellular PPIX fueled by administration of either ALA, MAL, or HAL for each 10 different concentrations. For simultaneous proliferation correction, A431 cells were stably transfected with green fluorescent protein. The results indicate that the peak PPIX level is a function of both, incubation concentration and period: maximal PPIX is generated with 1 to 2-mM ALA/MAL or 0.125-mM HAL; also, the PPIX peak shifts to longer incubation periods with increasing pro-drug concentrations. The results underline the need for detailed temporal analysis of PPIX formation to optimize ALA (derivative)-based PDT or photodiagnosis and highlight the value of environment-controlled microplate readers for automated in vitro analysis