Sr Fraction Research Articles

The Na+/Ca2+ exchanger Inhibitor KB-R7943 is also a potent inhibitor of EC coupling and ryanodine receptors

Background: Na+/Ca2+ exchanger (NCX) is a plasma membrane transporter that moves Ca2+ in or out of the cell depending on membrane potential and transmembrane ion gradients. NCX is the main pathway for Ca2+ extrusion from ventricular myocytes and has been extensively studied in this tissue. NCX inhibitors can ameliorate cardiac ischemia-reperfusion injury and this result has been attributed to inhibition of the Ca2+ inward mode of NCX. Here we tested two NCX inhibitors, KB-R7943 and SN-6 on adult dissociated skeletal muscle fibers loaded with Fluo-4 and [3H]ryanodine binding analysis. Results: KB-R7943 (5 and 10 μM) reversibly inhibits Ca2+ transients elicited by electrical stimulation. At the same concentrations SN-6 has no effect on the properties of transients. In order to evaluate a possible direct effect of KB-R7943 and SN-6 on RyR activity we performed [3H]-ryanodine binding assays because ryanodine binds to the channel in the open state and is used to evaluate channel conformation. Using a skeletal muscle SR fraction we found that 5 or 10 μM KB-R7943 inhibits high affinity binding of [3H]-ryanodine in a dose-dependent manner whereas SN-6 has negligible activity. Conclusion: Our results suggest that KB-R7943 is a potent and reversible blocker of RyR channels and EC coupling in adult fibers. The effects of these compounds on cardiac ischemia-reperfusion injury may be partially explained by their effect on RyR activity. Support: R01AR43140 & P01 AR52354

Precise determination of Sr isotope ratios in igneous rock samples and application to micro-analysis of plagioclase phenocrysts

A two-step chemical procedure to separate Sr from whole igneous rock sample has been developed for the analysis of Sr isotopes by thermal ionization mass spectrometry (TIMS). Firstly, a Sr-bearing fraction and a REE fraction are separated from the major elements of a decomposed sample solution using H+ form cation-exchange chromatography. Then the Sr fraction is purified in a second column using extraction chromatography and a Sr specific resin. For small amounts of sample (< 0.1 mg) obtained by micro-milling, only the second step of column separation is applied, directly separating the Sr fraction from the decomposed sample solution. The total procedural blank of these chemical separation procedures are very low, comparable to the lowest blank levels ever reported. The purified Sr is loaded on to a single Re-filament with a Ta ionization activator and measured using TIMS in static multi-collection mode. The mean value and reproducibility for standard 87Sr/86Sr in NIST SRM 987 with Sr loads of 100 ng and 5 ng are 0.710240 ± 0.000012(2σ, n = 12) and 0.710248 ± 0.000022 (2σ, n = 7), respectively. These values agree well with those from previous studies. Additionally, Sr isotope ratios measured in GSJ igneous rock reference materials JB-2, JA-1 and JR-1 are within error of values from previous studies, verifying the versatility of the technique reported in this study.

Systematic evaluation of a strontium-specific extraction chromatographic resin for obtaining a purified Sr fraction with quantitative recovery from complex and Ca-rich matrices

This paper presents a systematic evaluation of a commercially available strontium-specific extraction chromatographic resin based on a crown ether (Sr spec™), for use in applications of Sr isotope ratio analysis dealing with samples displaying a complex and/or Ca-rich matrix composition. A protocol, consisting of (i) loading a sample digest in 7 M HNO3 onto the resin, (ii) rinsing the resin with 7 M HNO3 to remove concomitant matrix elements and (iii) rinsing the resin with 0.05 M HNO3 to strip off the purified Sr fraction, was found to provide the best results. The performance in terms of (i) the purity of the Sr fraction obtained, (ii) the efficiency of Rb/Sr and Ca/Sr separation, (iii) the Sr recovery from samples with a complex and Ca-rich matrix composition and (iv) the Sr isotope ratios obtained using multi-collector ICP-MS, was evaluated for various amounts (250, 500, 750 and 2000 µL) of resin using digests of bone and soil certified reference materials, dental tissues, fluorite and glass samples. Further, it was investigated whether or not the isolation protocol introduces Sr isotopic fractionation. Also the possibility of regenerating the resin after use, allowing multiple use of the resin, was assessed. Finally, the Sr isotopic composition of 2 bone (NIST SRM 1400 Bone Ash and NIST SRM 1486 Bone Meal) and 2 soil (BCR CRM 141 Calcareous Loam Soil and BCR CRM 142 Light Sandy Soil) certified reference materials was determined. The method was shown to be fit-for-purpose for population migration studies and provenancing of archaeological artefacts, and is expected to be suited for a broad range of Sr isotope ratio applications.

Luminescence Efficiency Enhancement by Impurity Doping in SrIn2O4 : Pr3 +

A red-emitting phosphor, is a candidate of Cd-free phosphor for vacuum fluorescent tubes. Luminescence of is quenched at a Sr-rich composition by formation of defects that work as nonradiative centers. At the stoichiometric composition , the luminescence efficiency is increased by addition of , while decreased by addition. Measurement of the unit cell volume showed that and occupy the site, while presumably occupies the site. This site preference shifts the atomic ratio of the site to the Sr-poor side by doping and to the Sr-rich side by doping, resulting in an increase or a decrease in efficiency at the stoichiometric composition. Under electron excitation and at the dopant concentration of per . , doping provides the maximum efficiency about twice higher than the maximum efficiency of an undoped sample. The optimized Sr fraction for doping, , has led to efficiency about 2.7 times as high as efficiency of the undoped .

BST solid solutions, temperature evolution of the ferroelectric transitions

Solid solutions Ba 1 − x Sr x TiO 3 (BST) are of high technological importance, particularly in microwave domain. Barium titanate has “naturally” three transitions, between four stable ferroelectric phases: (C) cubic, (T) tetragonal, (O) orthorhombic, (R) rhombohedral. Jaffe et al . [B. Jaffe, W.R. Cook, H. Jaffe, Piezoelectric Ceramics, Academic Press, 1971] has given the dependence of the transition temperatures up to 30% of Sr content. We have extrapolated these temperatures and we have found that some phases might disappear at higher Sr concentrations. A family of solid solutions with x = 25, 50, 75, 90% was prepared by standard solid-state reaction and sintered at 1230 and 1260 °C, respectively. The permitivities and the dielectric losses were measured with a self-acting bridge (1 kHz), on a large temperature range (±200 °C). The composition x = 25% shows three peak values of permittivity as expected, while the composition x = 50%, only two peak values, corresponding to phase transitions cubic–tetragonal–rhombohedral, phase orthorhombic being excluded. Compositions with x ≥ 63%, Sr shows only one peak value corresponding to a genuine transition cubic–rhombohedral. The cubic transition to several lower phases shows almost a linear decrease of the Curie point with the increase of Sr fraction. For Sr concentration x ≥ 80%, the Curie point appears to fall more rapidly than linear. To our best knowledge, there is for the first time, this effect is reported.

Dopant influence on BST ferroelectric solid solutions family

Solid solutions of the Ba 1− x Sr x TiO 3 (BST) type are very attractive for applications in information technology, but also in microwaves for such electrically controlled devices as phase shifters, tunable filters, steerable antennas, varactors, etc. A family of solid solutions with x = 25, 50, 75, 90% was prepared by standard powder technology-solid state reaction and sintered at 1230 °C and 1260 °C. Dielectric permittivity and loss at low (1 kHz) and high frequency (1 ÷ 2 GHz) were measured on a large temperature range − 200 °C ÷ + 200 °C. The influence of Sr content and of 1 wt.% MgO and 1 wt.% MnO 2 doping on the complex dielectric constant was studied. The dielectric permittivity at high frequencies and room temperature considerably decreases with the increase of Sr content. Similarly, low frequency measurements showed a severe and almost linear decrease of the Curie Point with the increase of Sr fraction. At low Sr content, the measured ceramic densities slowly decrease with Sr fraction and represent about 92% of the X-ray density ρ(g/cm 3) ≈ 5.99–0.99· x. At x = 90% Sr concentration, very low-density ceramics were obtained with both sintering temperatures.

Relative contributions of silicate and carbonate rocks to riverine Sr fluxes in the headwaters of the Ganges

Exhumation of the Himalayan-Tibetan orogen is implicated in the marked rise in seawater 87Sr/ 86Sr ratios since 40 Ma. However both silicate and carbonate rocks in the Himalaya have elevated 87Sr/ 86Sr ratios and there is disagreement as to how much of the 87Sr flux is derived from silicate weathering. Most previous studies have used element ratios from bedrock to constrain the proportions of silicate- and carbonate-derived Sr in river waters. Here we use arrays of water compositions sampled from the head waters of the Ganges in the Indian and Nepalese Himalaya to constrain the end-member element ratios. The compositions of tributaries draining catchments restricted to a limited range of geological units can be described by two-component mixing of silicate and carbonate-derived components and lie on a plane in multicomponent composition space. Key elemental ratios of the carbonate and silicate components are determined by the intersection of the tributary mixing plane with the planes Na = 0 for carbonate and constant Ca/Na for silicate. The fractions of Sr derived from silicate and carbonate sources are then calculated by mass-balance in Sr-Ca-Mg-Na composition space. Comparison of end-member compositions with bedrock implies that secondary calcite deposition may be important in some catchments and that dissolution of low-Mg trace calcite in silicate rocks may explain discrepancies in Sr-Ca-Na-Mg covariation. Alternatively, composition-dependent precipitation or incongruent dissolution reactions may rotate mixing trends on cation-ratio diagrams. However the calculations are not sensitive to transformations of the compositions by incongruent dissolution or precipitation processes provided that the transformed silicate and carbonate component vectors are constrained. Silicates are calculated to provide ∼50% of the dissolved Sr flux from the head waters of the Ganges assuming that discrepancies between Ca-Mg-Na covariation and the silicate rock compositions arise from addition of trace calcite. If the Ca-Mg-Na mixing plane is rotated by composition-dependent secondary calcite deposition, this estimate would be increased. Moreover, when 87Sr/ 86Sr ratios of the Sr inputs are considered, silicate Sr is responsible for 70 ± 16% (1σ) of the 87Sr flux forcing changes in seawater Sr-isotopic composition. Since earlier studies predict that silicate weathering generates as little as 20% of the total Sr flux in Himalayan river systems, this study demonstrates that the significance of silicate weathering can be greatly underestimated if the processes that decouple the water cation ratios from those of the source rocks are not properly evaluated.

Determination of the 87Sr/ 86Sr isotope ratio in USGS silicate reference materials by multi-collector ICP–mass spectrometry

Multi-collector ICP–mass spectrometry (MC-ICP–MS) was used for 87Sr/ 86Sr isotope ratio determination in newly introduced silicate reference materials from the US Geological Survey (USGS): granite G-3, andesite AGV-2, and basalt BCR-2. Next to the SrCO 3 isotopic standard NIST SRM 987, also analogous USGS reference materials from the previous generation, and for which reference 87Sr/ 86Sr data obtained by TIMS are available, were analysed for validation purposes. Sample preparation consisted of acid digestion and subsequent isolation of Sr by means of a dedicated and commercially available crown ether-based resin. The Sr fractions thus obtained were analysed via MC-ICP–MS whereby mass discrimination was corrected for internally, while the isobaric interference at a mass-to-charge ratio of 86 caused by Kr impurities in the Ar gas was mathematically corrected for by using the signal for a Kr isotope free from spectral overlap. Finally, also the effect of the small amount of Rb that may still be present in the Sr fraction was corrected for mathematically on the basis of the signal intensity for 85Rb. The MC-ICP–MS results for G-2, AGV-1 and BCR-1 showed an excellent agreement with the corresponding TIMS values (<0.003% bias in all cases), such that it can be assumed that also the 87Sr/ 86Sr isotope ratio results obtained for the new reference materials are reliable.

D.C. conduction mechanisms of certain perovskite ceramics

A series of a complex perovskite Ca x Sr(1 − x)TiO3 (CST) where (0 ≤ x ≤ 1) has been prepared by mechanical mixing of their oxides (CaTiO3 and SrTiO3). X-ray diffraction showed that no traces of other compounds and the line widths indicated that the products were homogeneous. The d.c. conductivity of the sample were measured over the range of temperature between 303–800 K. Temperature dependent of d.c. measurement revealed that the conductivity is thermally activated. Over the low temperature range between (333–573 K) for CaTiO3, (353–483 K) for Ca0.7Sr0.3TiO3 and (373–423 K) for Ca0.5Sr0.5TiO3 a semiconductor—metal behavior was observed. From the relationship between activation energy Ea and the compositions, it has been found that Ea goes through a minimum around 50% Sr—fraction. The field lowering coefficient β is evaluated experimentally.

Approaches to90Sr determination in marine environmental materials

The determination of Sr in seawater, sediment and biota is carried out by radiochemical analysis. The choice of method is dependent on the amount of sample to be analyzed, die Ca/Sr mass ratio and the natural Si content of the sample. For large volumes of seawater and sediment samples (e.g., coral) of high Ca content, 1 g (minimum) of Sr carrier and 5 Sr tracer are used. The Sr fraction is separated and purified chiefly by Sr(N0 3 )2 precipitations. After 2-3 weeks, die ingrown 90 Y is separated from the parent 'Sr, and the 90 Y beta activity is measured by a gas-flow proportional counter. The detection limits obtained are 36 fiBq/L for seawater and 0.36 Bq/kg for corals. For sediment and biota samples of low to moderate Ca content and low natural Sr content, 10 - 20 mg of stable Sr carrier are used without 85 Sr. The Sr fraction is separated and purified using crown ether extraction chromatography. The purified Sr fraction itself (containing 'Sr together with in-growing 90 Y) is measured immediately using liquid scintillation counting. The detection limit obtained is 0.66 Bq/kg for lOg of sediment or

The use of sector field ICP-mass spectrometry for Rb-Sr geochronological dating.

Rb-Sr dating, one of the most important tools in geochronology, requires determination of the Rb/Sr concentration ratios and the 87Sr/86Sr isotope ratios in co-genetic minerals or rocks and is traditionally performed by thermal ionization mass spectrometry (TIMS). In this work we investigated whether sector field inductively coupled plasma mass spectrometry (ICP-MS), which is characterized by a high sample throughput and straight-forward sample introduction, could be used as an alternative to TIMS. To avoid spectral overlap of the ion signals of the isobaric nuclides 87Sr and 87Rb, Sr was separated from Rb by cation-exchange chromatography. A mathematical correction was applied to take into account the small amount of Rb that can be present in the Sr fraction. The isotope ratio accuracy and precision attainable with ICP-MS were evaluated by analysis of several reference materials from the US Geological Survey. The results of this evaluation show that excellent accuracy could be achieved; the internal precision (repeatability) of the isotope ratio (expressed as the relative standard deviation for 10 successive 1-min measurements) was 0.04-0.12%. An attempt was made to calculate the total or combined uncertainty on the isotope ratio results, by also taking into account other possible error sources (corrections for mass discrimination, detector dead time, blank signal and Rb fraction). Finally, the same procedure was used for dating two rock formations that were 2,500 Ma and 350 Ma old, according to age determinations previously performed by the Rb-Sr laboratory of the University of München (Germany) using TIMS. The ICP-MS results (2,520 +/- 150 Ma and 379 +/- 48 Ma) obtained for these formations compare well with the corresponding TIMS data (2,509 +/- 120 Ma and 357 +/- 25 Ma).

Purification of Follicular Regulatory Protein: Possible Plasminogen Identity

A partially purified protein (the SR fraction) of porcine and human origin has been extensively characterized as Follicular Regulatory Protein (FRP). In the current study, 1A8D5, one of several monoclonal antibodies raised against FRP, was used to further purify the protein. The monoclonal antibody cross-reacted only with porcine plasminogen, a key fibrinolytic proenzyme. A commercial polyclonal antibody for human plasminogen confirmed the relationship between plasminogen and bands of the SR fraction of the porcine follicular fluid. Sequencing of the N-terminal amino acids (54 kd) of the SR fraction indicated that it shared 100% identity with the short form of porcine plasminogen chain A and 93% identity to human plasminogen. Moreover, we demonstrated that this purified protein from human follicular fluid inhibited aromatase activity of granulosa cells, a key biological property of FRP. Given that plasminogen possesses most of the proposed properties of the protein termed FRP, we conclude that FRP is likely plasminogen itself or a plasminogen-related protein and not a novel protein.

Hydrothermal synthesis of ferroelectric barium and strontium titanate extremely fine particles

BaTiO3, SrTiO3 and (Ba1− xSrx)TiO3 fine particles were synthesized from amorphous TiO2 fine particles by a hydrothermal method. The relationship between the specific dielectric constant of the sintered disk and the mean size of composing particles has been investigated. The specific dielectric constants of the sintered disks of BaTiO3 and SrTiO3 particles attain values exceeding 6000 in the range of the particle size of 0.10–0.17 μm. The specific dielectric constant for the sintered disk of (Ba1− xSrx)TiO3 particles synthesized at various atomic fractions of Sr (x) attains maximum values at both atomic fractions of 0.08 and 0.95. It has been suggested that the size of particles composing the disk should considerably affect the specific dielectric constant of the sintered disk.

Determination of metal-humic complexes, free metal ions and total concentrations in natural waters.

A comparison of two systems for the quantitation of metal-humic complexes and free metal ions, consisting of the separation by coupled ion exchange columns followed by detection by inductively coupled plasma mass spectrometry or cold vapour atomic fluorescence spectrometry, is presented. The systems evaluated comprised the serially coupled anion and cation exchangers, Sephadex A-25/Chelex 100 and Dowex 1X8/Chelamine Metalfix. Separation and preconcentration of the species studied were accomplished with both systems, elution being carried out using 2 M HNO3. Total concentrations, metal-humic complex fractions and free metal ion fractions of Al, Ba, Cd, Co, Cu, Fe, Hg, Mn, Pb, Sr, U and Zn in nine natural waters were determined. Statistical evaluation of the data from the two cation exchange materials, including results for additional elements, showed better precision (for Al, Ba, Cr, Cu and Mo) and higher recoveries (Al, Ba, Cd, Fe, Sr and Zn) for Chelex 100 than Chelamine Metalfix for free metal ions. On the other hand, Chelamine Metalfix recovered a significantly greater amount of Ni. The amounts of metal-humic complexes were compared with modelled distributions of these species, and one advantage of the preferred Sephadex A-25/Chelex 100 system is that the elements studied are all correctly classified with respect to their binding strengths to humic substances, which is not the case with the Dowex 1X8/Chelamine Metalfix pair. With the preferred system, metal-humic complexes can be reliably determined, as indicated by the results of equilibrium speciation modelling. However, comparison with the total concentrations showed statistically significant, non-quantitative recoveries of Al, Cu, Hg, Mn, U and Zn from some samples. Thus a combination of speciation and total concentration measurements is required to obtain a complete representation of the distribution of trace elements in natural waters.

The Cardiac Content of Sarcoplasmic Reticulum in the Rat Determined by Calcium Uptake Rate, Calcium Oxalate Capacity, Ryanodine Binding and Thapsigargin Titration

The amount of cardiac sarcoplasmic reticulum in rat hearts was estimated by comparing marker activities in the isolated SR fraction with their activities in the homogenate. Four distinguishable markers were measured: the oxalate-supported rate of calcium uptake, the calcium oxalate capacity,3H-ryanodine binding and the thapsigargin equivalents. The calcium uptake rate and capacity and thapsigargin equivalents were determined in the presence and absence of SR Ca2+channel blockade with high concentrations of ryanodine. All of these activities are believed to be located only in the SR. However, the calculation of the heart content of SR was somewhat different for the four markers. The calcium uptake rate gave 8.4 mg SR protein per g tissue in the absence of ryanodine, and 9.6 mg per g in its presence; calcium oxalate capacity gave similar numbers, 9.9 mg per g in the absence of ryanodine and 8.0 mg per g in its presence. The thapsigargin titration gave similar equivalent with or without ryanodine, indicating that the homogenate contained about 8.0 mg of SR per g tissue. Using3H-ranodine binding as a marker, the cardiac content of SR was calculated to be 16.7 mg per g. These differences are attributed to the non-ideal behavior of these markers. Some of the Ca2+uptake activity is not thapsigargin sensitive, and some of the3H-ryanodine binding does not fractionate with the SR Ca2+uptake activity.

Determination of oxygen permeation kinetics in a ceramic membrane based on the composition SrFeCo 0.5O 3.25− δ

The oxygen permeation through an oxide ceramic membrane with bulk composition SrFeCo 0.5O 3.25− δ has been measured as a function of both temperature and the oxygen pressure gradient across the membrane. The form of the pressure gradient dependence of the permeation indicates that the oxygen transport in the membrane is dependent primarily on the bulk diffusion rate. Although the permeation experiments were carried out at temperatures within, or very close to, the range where SrFeCo 0.5O 3.25− δ is stable as a pure single phase in air, the membrane was found to consist of SrFe 1.5− x Co x O 3.25− δ ( x=∼0.42) together with fractions of Sr(Co 1− x Fe x )O 2.5− δ perovskite and Co–Fe oxide. Phase stability experiments indicate these phases formed as a stable assemblage when the membrane was densified at high temperature (1090°C) during final processing. The assemblage persists at the lower temperatures of the permeation experiments most likely because of slow re-equilibration kinetics.

Dielectric characteristics of doped Ba 1 − xSr xTiO 3 at the paraelectric state

Ba 1 − x Sr x TiO 3 ( x = 0 to 1) ferroelectric ceramics doped with 1.0 mol.% MgO and 0.05 mol.% MnO 2 wereprepared with a rate-controlled sintering profile. The lattice constant of this BST system decreases as the strontium molar fraction increases. This is due to the smaller Sr 2+ ionic radius than that of Ba 2+. The temperature dependence of the dielectric constant is measured at 10 kHz. A linear relation of the Curie temperature of the BST system to the Sr fraction for x ≤ 0.75 is observed. When this reaction is fitted to a modified Curie-Weiss law, two parameters, the critical exponent and the diffuseness parameter, which represent the order of transition broadening, can be calculated. From the values of these two parameters, it is suggested that the physical meanings of these two parameters are correlated to each other. The transition broadening is greatest for x = 0.5 owing to the most composition fluctuation. Dipole relaxation of the composition with x = 0.25 is observed at frequencies above 1 MHz. On the basis of Cole-Cole analysis, a low frequency relaxation due to dopants Mn 4+ at below 50 kHz is observed.

Experimental, geochemical, mineralogical and O-isotope constraints on the late-magmatic history of the Fichtelgebirge granites (Germany)

Mineralogical, experimental, geochemical and stable-isotope data give evidence for an aqueous late-stage fluid which develops increasingly from the less to the more highly evolved granites of the Fichtelgebirge (G1–G4). In less-evolved granites (particularly G1) only minor chloritization and sericitization, minor hydration and corrosion of zircons, low leachable fractions of Sr and Zr, the nearly chondritic ratios of Zr/Hf and Y/Ho, and rare-earth-element (REE) patterns lacking the tetrad effect provide evidence of a less-differentiated granitic melt system, poor in complexing agents and water, with insignificant late magmatic fluid–rock interaction. The subsequent low-temperature alteration, which is suggested by oxygen-isotope composition of quartz and biotite, did not affect the whole-rock chemical composition. In the highly evolved granites (particularly G4), albitization, sericitization and fluoritization, ubiquitous hydration and corrosion of zircons, high leachable fractions of Sr and Zr, Zr/Hf and Y/Ho ratios very different from the chondritic ratios, and REE patterns showing a marked tetrad effect point to the presence of a highly specialized fluid system, rich in water and complexing agents, such as fluorine, leading to a marked magmatic–hydrothermal alteration. The oxygen isotopes also indicate alteration by high-temperature fluids which were likely exsolved during the final stage of crystallization.

Magnetic properties of the doped manganites: A meanfield

The main features of the experimental observations of Urushibara et al. on the magnetic properties of La Sr MnO are fitted to a mean-field model. Using the ideas of Zener and of Goodenough, the observed shift in the Neel temperature, the transition from antiferromagnetism to ferromagnetism and the parabolic variation in Curie temperature with Sr fraction are seen to be compatible with semicovalent exchange interactions through hybridized O 2p orbitals together with a double-exchange-like ferromagnetic interaction through holes introduced by the substitution of divalent for trivalent cations.

Exchangeable fraction of elements in alluvial sediments under waste disposal site (Zagreb, Croatia)

Concentrations of Ag, Ba, Cd, Ce, Cs, Co, Cr, Eu, Fe, Rb, Sc, Sr, Th, and Zn exchangeable fractions were determined in alluvial sediments at waste disposal site area in the vicinity of water-well field. Samples have been leached with 0.5M NH4Cl at a sample/solution ratio of 1∶20 during 24 hours without shaking. INAA of dry NH4Cl residues show that the concentrations of exchangeable elements determined in the most of the sediments below the wastes have natural levels. Ag, Ba and Sr are readily exchangeable; Rb, Cs and Zn have lower exchangeability, while Cd, Ce, Th, Sc, Eu, Cr, Fe and Co are rather immobile. Extremely high total and exchangeable silver concentration was found at 6.5–6.8 meters below waste in the aerated layer occasionally under the water table. Exchangeable concentrations in deeper water-bearing sediment layers are not elevated. Due to this, one can presume that the upper sediment layers act as chemical filter generally preventing the infiltration from overlying wastes into water-bearing layers.