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The main goal of this research is to define reference values of elemental concentration in human urine. The second topic is to develop a fast analytical method for multielemental analysis of human urine by means of a low-power benchtop total reflection X-ray fluorescence system. For this purpose a set of certified human urine and real samples was employed. All of the parameters affecting sample preparation and measurement conditions were carefully evaluated, and finally, the procedure for optimal urine preparation and optimal measurement conditions is defined. The accuracy and precision of the measurements were verified using an internal standardization approach for quantification. As results, the reference values of concentration of several elements (K, Ca, Cr, Mn, Fe, Ni, Cu, Zn, Br, Rb and Sr) were defined on the basis of the analysis of 100 urine samples. Donors were presumably healthy volunteers from the Świetokrzyskie Province in Poland: 62 women and 38 men. Because of the strong asymmetry of elemental concentration distributions, the median and the 1st and 3rd quartiles reflect features of the distributions better than the mean value and standard deviation (which are proper for symmetric distributions). Finally, the 1st and 3rd quartiles were accepted as the initial and final values of the concentration reference range. For measurements, in which the concentration is below the detection limit of the method used (i.e. for Cr, Mn, Cu, Se), the well-known random-left censoring approach was applied for the statistical analysis of the results.

Total reflection X-ray photoelectron spectroscopy (TRXPS) is applied in the analysis of Ti and TiO2 nanolayers deposited on silicon and silicon dioxide substrates. The idea of application of total-reflection phenomenon for exciting X-ray used in the XPS technique is briefly discussed. The experimental setup and measurement conditions for the studied Ti and TiO2 layers are presented. The XPS spectra were registered both for the non-total and total reflection regimes. The survey spectra and C1s, N1s, Ti2p and O1s photoelectron peaks are shown. For energy calibration, the position of C1s photoelectron peak was applied (C-C component, binding energy 284.8 eV). The peak to background ratios are discussed as regards the dependence of the excitation angle. An increase of this ratio for the glancing angle 1°, being below critical angle of the X-ray beam and sample material, results in an improvement of XPS detection limit by factor up to 2. In the case of the Ti nanolayer, additionally, the thickness of the overlayer TiO2 is determined. As an example of applying the TRXPS technique, the analysis of Ti nanolayers implanted by highly charged Xe35+ ions of 280 keV energy is discussed. The Xe3d and O1s photoelectron peaks are presented and discussed.

The heterogeneous nature and widespread anthropogenic impacts on industrial water biotopes in the Trzuskawica S.A., pose challenges to biomonitoring of this habitat. Generally, the concentration of trace elements in the industrial water biotopes reflects the anthropogenic impacts. With X-ray fluorescence method (TXRF) in waters 17 elements:P,S,Cl,K,Ca,Ti,Cr, Mn,Fe,Ni,Cu,Zn,Br,Rb, Sr, Ba, Pb were revealed. High amounts of Ca, from 300 ppm to 198 ppm in May and from 999 ppm to 231 ppm in September 2015, was determined. A total of 36 diatoms were found in two reservoirs and drainage ditch, but only three taxa: Cymatopleura radiosa, Navicula upsaliensis and Nitzschia angustata were present in all 7 sampling sites. These species are known to be tolerant to organic pollution, eutrophication, and also characteristic for limestone waters. The results of CVA showed that dintoms in the water reservoir stocked with fish were distinguished by highest species richness. The relationships between diatoms and environmental variables confirm the positive correlation with the currently functioning industrial plant (despite the increased water temperature and large content of trace elements). Our results suggest that, though heterogeneity in both diatoms and selected elements in industrial waters, diatoms can be useful indicators of habitat conditions.

The measurements of the M- and N-shell ionization probabilities in gold bombarded by highly charged S q+ (q = 4–14) ions of energy 0.4–3.8 MeV/amu are reported. The ionization probabilities were extracted from the measured L-X-ray spectra which were substantially modified by the multiple ionization effects. The observed L-X-ray line shifts and broadening allowed us (Banaś et al., 2002) to extract both the M- and N-shell ionization probabilities for the zero impact parameter. These ionization probabilities, which correspond to the moment of X-ray emission , were correlated with the ionization probabilities for the moment of ion impact ionization by using the vacancy rearrangement procedure developed here. In this way the ionization probabilities for the moment of ion impact multiple ionization were obtained. By comparing to the theoretical predictions of the semiclassical approximation (SCA) (Trautmann and Kauer, 1989) and the “geometrical model” (GM) (Sulik et al., 1987) based on the binary encounter approximation (BEA), the role of the electronic wave functions and the binding effect is discussed. Generally, the calculations using the hydrogenic wave functions reproduce the measured ionization probabilities.

Total reflection X-ray fluorescence analysis and X-ray powder diffraction were used for elemental and chemical composition analysis of 83 samples of human kidney stones. Samples came from patients after surgical removal of stones. Elements such as P, K, Ca, Fe, Zn, Ni, Br, Sr, and Pb were determined in all samples. Other elements Mg, S, Cl, Ti, V, Cr, Mn, Cu, Se, Rb, I, and Bi were found in some of the analyzed kidney stones (censoring effect). Descriptive statistics were calculated for all elements paying particular attention to the censored elements. From diffraction measurements, the following crystalline substances were determined in the stones: apatite, struvite, uric acid, weddellite, whewellite, magnesium phosphate, and calcium phosphate. Information of chemical composition was applied to classify the analyzed kidney stone into four groups. Statistical analysis of the results included multigroups comparison, testing of element concentration distribution, and elemental correlations in the dependence of kind of kidney stones. The presented studies are part of wider microbiological studies focusing on the correlation between different kinds of bacteria and fungi presented in the samples of kidney stones and their elemental as well as chemical composition. Information on stone composition can be helpful in understanding kidney stone formation and complemented by additional metabolic blood and urine tests. This, in turn, can lead to appropriate medical treatment together with the reduction of the risk as regards forming new stones.

Total reflection X-ray fluorescence (TXRF) analysis was applied in determination of low concentration of lead in samples of human biological materials. The determination of lead in human serum and hair samples is presented as an example. In serum samples, lead concentration was in the range from 0.013 to 0.051 μg/g (median 0.024 μg/g). The reference ranges of lead content in hair are from 1.41 to 4.08 μg/g for men and from 1.18 to 3.29 μg/g for women groups, respectively. Because of Pb concentration range close to the detection limit of the TXRF method, the measurement needed evaluation of the best analytical conditions. This paper presents the results of this evaluation, namely internal standard selection, measurement conditions, and quantitative calibration of the spectrometer. Finally, as a result of evaluation, the detection limit was found on the level 0.001 μg/g (water solution) and about 0.005 μg/g for human hair samples and 0.007 μg/g for serum samples. The obtained values reach nearly the physiological lead level. The presented results are of practical importance for lead concentration studies in human biological materials using the TXRF method. Copyright © 2016 John Wiley & Sons, Ltd.

Deficiency or excess of elements could disrupt proper functioning of the human body and could lead to several disorders. Determination of their concentrations in different biological human fluids and tissues should become a routine practice in medical treatment. Therefore the knowledge about appropriate element concentrations in human organism is required. The purpose of this study was to determine the concentration of several elements (P, S, Cl, K, Ca, Cr, Fe, Cu, Zn, Se, Br, Rb, Pb) in human serum and to define the reference values of element concentration. Samples of serum were obtained from 105 normal presumably healthy volunteers (66 women aged between 15 and 78 years old; 39 men aged between 15 and 77 years old). Analysis has been done for the whole studied population and for subgroups by sex and age. It is probably first so a wide study of elemental composition of serum performed in the case of Świetokrzyskie region. Total reflection X-ray fluorescence (TXRF) method was used to perform the elemental analysis. Spectrometer S2 Picofox (Bruker AXS Microanalysis GmbH) was used to identify and measure elemental composition of serum samples. Finally, 1st and 3rd quartiles were accepted as minimum and maximum values of concentration reference range.

A particular subject of X-ray fluorescence analysis is its application in studies of the multielemental sample of composition in a wide range of concentrations, samples with different matrices, also inhomogeneous ones and those characterized with different grain size. Typical examples of these kinds of samples are soil or geological samples for which XRF elemental analysis may be difficult due to XRF disturbing effects. In this paper the WDXRF technique was applied in elemental analysis concerning different soil and geological samples (therapeutic mud, floral soil, brown soil, sandy soil, calcium aluminum cement). The sample morphology was analyzed using X-ray microtomography technique. The paper discusses the differences between the composition of samples, the influence of procedures with respect to the preparation of samples as regards their morphology and, finally, a quantitative analysis. The results of the studies were statistically tested (one-way ANOVA and correlation coefficients). For lead concentration determination in samples of sandy soil and cement-like matrix, the WDXRF spectrometer calibration was performed. The elemental analysis of the samples was complemented with knowledge of chemical composition obtained by X-ray powder diffraction.

Particle-induced X-ray emission (PIXE) technique is usually applied using typically 1 MeV to 3 MeV protons or helium ions, for which the ion-atom interaction is dominated by the single ionization process. For heavier ions the multiple ionization plays an increasingly important role and this process can influence substantially both the X-ray spectra and atomic decay rates. Additionally, the subshell coupling effects are important for the L- and M-shells ionized by heavy ions. Here we discuss the main features of the X-ray emission induced by heavy ions which are important for PIXE applications, namely, the effects of X-ray line shifts and broadening, vacancy rearrangement and change of the fluorescence and Coster–Kronig yields in multiple ionized atoms. These effects are illustrated here by the results of the measurements of L X-ray emission from heavy atoms bombarded by 6 MeV to 36 MeV Si ions, which were reported earlier. The strong L-subshell coupling effects are observed, in particular L 2 -subshell, which can be accounted for within the coupling subshell model (CSM) developed within the semiclassical approximation. Finally, the prospects to use heavy ions in PIXE analysis are discussed.

The aim of this research is to develop a fast analytical method for multielemental analysis of the tobacco plant Virginia tobacco (cultivated in Poland) and tobacco products (cigarettes, cigars, cigarillos, snuff and two kinds of properly crafted tobacco such as a shisha and cigarette tobacco) distributed in Polish markets by means of a low-power benchtop total reflection X-ray fluorescence (TXRF) system. For this purpose, a set of certified tobacco materials and real samples was employed. In leaves and stalks of V. tobacco and tobacco products, a concentration of 18 elements (P, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Br, Rb, Sr and Pb) was determined. Analyzing elemental composition of tobacco plants, one can see that concentrations of S, Ca, Ti, Mn, Zn, Sr and Pb are higher in leaves, whereas the concentrations of P, Cl, K, Fe Cu and Br are higher in stalks; the levels of Cr, Ni, As and Rb are comparable in both these parts of the tobacco plant. All of the parameters affecting sample preparation and TXRF measurements conditions were carefully evaluated. The accuracy and precision of the TXRF measurements were verified using an internal standardization approach for quantification.

The results of the elemental and chemical composition analysis of human medical samples (blood, serum, hair, urine, tooth, kidney stones, gallstones) and environmental samples (slag, cereal, vegetables, our, pork bones, pork meat, sh) are presented. The analysis were performed by application of the total re ection X-ray uorescence, wavelength dispersive X-ray uorescence and X-ray powder di raction methods. With X-ray uorescence methods the following elements were identi ed: O, Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, Mn, Fe, Ni, Cu, Zn, Se, Br, Rb, Sr, Zr, I, Ba, and Pb, whose concentrations were from a few ng/g to tens of percent. For some samples the elemental analysis was extended by X-ray powder di raction measurements. With this method the chemical composition was determined. In the paper the experimental setups, methodology of samples preparation and methods of carrying out the measurements are described. As an example the X-ray spectra registered for gallstone sample are discussed in detail. Finally, the results of X-ray di raction and elemental analysis for selected medical and environmental samples are summarized.

Elemental and chemical composition of raw and activated samples of halloysite mineral using wavelength dispersive X-ray fluorescence (WDXRF), total reflection X-ray fluorescence (TXRF) and X-ray powder diffraction (XRPD) methods were determined. As the result, it has been shown that application of the complementary X-ray spectrometry techniques allows very precise observation of changes in composition of halloysite mineral samples caused by its chemical modifications. Sample preparation procedure and usability of the research methods applied are described in details. Procedure of activation of raw halloysite mineral samples by etching them in sulfuric acid of various concentrations has been described and discussed. The ability of the samples to adsorb lead from intentionally contaminated water was tested and confirmed.

X-ray fluorescence analysis methods (wavelength dispersive X-ray fluorescence analysis (WDXRF) and total reflection X-ray fluorescence (TXRF)) and X-ray powder diffraction (XRPD) have been applied in complementary geochemical studies of the Pleistocene till samples. The XRPD technique gave information about the mineral composition of the analyzed samples while the WDXRF and TXRF studies allowed the fast elemental analysis. The till samples were collected from different regions of Holy Cross Mountains (located in central Poland) which are still not unambiguously described in the context of the geochemical studies of the Quaternary sediments. The analysis was concentrated on the geochemical composition of the till samples both for materials occurring on the surface (characterized by continuous weathering processes) and for samples taken from core borehole. The overriding purpose of these studies is determination of the local lithotype of the tills and its lithologic and petrographic diagnostic properties, including the chemical composition of clay and minerals found in the clay. In the presented work the experimental sets up, sample preparation procedure and measurements programme will be discussed in details. Finally, the elemental and mineral compositions will be presented for studied different groups of the samples.

The L-shell X-ray production cross sections have been measured for sulphur ions in the energy range of 12.8–120 MeV for Au and Bi elements. The experimental L X-ray spectra were analyzed using the method that takes into account the multiple ionization in outer shells. The L-subshell ionization cross sections have been obtained from measured X-ray production cross sections for resolved Lα 1,2 Lγ 1 and Lγ 2,3 transitions using the L-shell fluorescence and Coster–Kronig yields modified by the multiple ionization effects in the M and N shells. The results are compared with the predictions of ECUSAR theory, which is the modified ECPSSR approach describing both direct ionization and electron-capture processes and the semiclassical approximation (SCA) calculations for direct ionization. These approaches were modified by the L-subshell coupling effects within the “coupled-subshell model” (CSM). Both modified approaches are in good agreement with the data. Remaining discrepancies are discussed in terms of the L-shell decay rates modified for the multiple ionization effects.

The total reflection X-ray fluorescence method was applied to study the trace element concentrations in human breast malignant and breast benign neoplasm tissues taken from the women who were patients of Holycross Cancer Centre in Kielce (Poland). These investigations were mainly focused on the development of new possibilities of cancer diagnosis and therapy monitoring. This systematic comparative study was based on relatively large (∼ 100) population studied, namely 26 samples of breast malignant and 68 samples of breast benign neoplasm tissues. The concentrations, being in the range from a few ppb to 0.1%, were determined for thirteen elements (from P to Pb). The results were carefully analysed to investigate the concentration distribution of trace elements in the studied samples. The measurements of concentration of trace elements by total reflection X-ray fluorescence were limited, however, by the detection limit of the method. It was observed that for more than 50% of elements determined, the concentrations were not measured in all samples. These incomplete measurements were treated within the statistical concept called left-random censoring and for the estimation of the mean value and median of censored concentration distributions, the Kaplan–Meier estimator was used. For comparison of concentrations in two populations, the log-rank test was applied, which allows to compare the censored total reflection X-ray fluorescence data. Found statistically significant differences are discussed in more details. It is noted that described data analysis procedures should be the standard tool to analyze the censored concentrations of trace elements analysed by X-ray fluorescence methods.

To achieve the low ppb detection level a major experimental effort and optimization of the TXRF setup are required. The new solution described in this paper leads to enhancement of the TXRF intensity and to improved signal/noise ratio. The adjusted quartz reflector allows control of a reflection angle of a photon beam with respect to the crystal surface with high precision up to 0.006°. The installed adjusted diaphragm (followed by the quartz reflector) substantially reduces the level of registered background in the studied range of x-ray energy. The dependence of the x-ray spectra shape, x-ray intensity and detection limit on the diaphragm width and its position on the photon beam as well as on the value of the glancing angle of x-rays from the sample carrier have been studied. The new optimal parameters found result in essential improvement in detection limit equal to ∼1.0 ppb for elements detected in a liquid sample without any special pre-concentration preparation. Also a very good repeatability of measurements has been reached. Copyright © 2006 John Wiley & Sons, Ltd.

The coupling and binding effects in ionization of L-shell electrons by heavy ions have been studied by measuring the L γ (L–N,O) X-ray transitions in gold excited by an impact of O, Si and S ions in the energy range 0.3–5 MeV/amu. The L-subshell ionization cross sections were extracted from measured X-ray spectra taking into account their substantial modifications due to the multiple ionization effects, which also change the fluorescence and Coster–Kronig yields. In order to interpret the data the L-subshell couplings were incorporated in the theoretical calculations based on the semiclassical approximation (SCA) within the “coupled subshell model” (CSM). Resulting SCA–CSM calculations, which describe the data for oxygen ions quite satisfactory, are further modified to include the saturation of the binding effect in order to describe the data for heavier Si and S ions. We find that the semiclassical SCA–CSM calculations of L-shell ionization by heavy ions ( Z 1 ≫ 1), which include corrections both for coupling and binding saturation effects, agree reasonably well with the measured data.

The effect of the projectile K X-rays line shifts with respect to the corresponding diagram lines has been used for evaluation of a mean equilibrium charge, q ¯ , for sulphur ions passing with energies of 9.6, 16.0, 22.4 and 32.0 MeV through Al, Ti and Fe foils. The q ¯ values for sulphur ions passing through Al and reference C foils are approximately equal for the all discussed energies. In the case of Ti and Fe foils the q ¯ values are greater for the smallest energy and the difference between q ¯ values in these two groups of targets is decreasing with increasing sulphur ion energy. For sulphur ions with energy of 32.0 MeV there is no difference in q ¯ values in all targets.

The use of x-ray fluorescence techniques (XRF, TXRF, μXRF) in studies of trace element concentrations is limited by the detection limits (DL) of these methods. In this work we demonstrate that concentration measurements below the DL level, the so-called 'non-detects', can be included in data analysis by using the statistical concept of 'censoring', which is widely used, for instance, in survival analysis. This paper describes the non-parametric methods of analysis of censored data using the random left-censoring formalism, which can be used to account for the detection limits in XRF analysis. In particular, the application of the Kaplan-Meier and Nelson-Aalen estimators for the estimation of concentration distributions under censoring is discussed. These approaches are compared with the 'reconstruction method' developed earlier in our group to correct XRF data for the effect of detection limits. By using Monte Carlo simulations, the accuracy of the Kaplan-Meier and Nelson-Aalen estimators for censored data is discussed, in particular in the context of the estimation of the mean value and median of a concentration distribution. We demonstrate that for the 'two-group' comparison of left-censored concentrations, which is a problem of great practical importance, the log-rank test can be used. The idea of random left censoring is applied to analyse the TXRF detection limit-censored measurements of the concentrations of trace elements in biomedical samples.

Element concentrations of K, Ca, Ti, Cr, Fe, Ni, Cu, Zn, Se, Br, Sr and Pb as well as the activity of natural radionuclides 210 Pb and 226 Ra in air were measured. The aerosol samples were collected during tropospheric and stratospheric aircraft flights over the Northeastern region of Poland, which is mostly an agricultural and wooded area. The air volumes were filtered using Petrianov filters at 1, 3, 6, 9, 12 and 15 km above the ground level by special equipment attached to a jet plane. Aircraft flights were provided from September 1997 to August 1998 in 5 separate sampling runs. The long sampling distances served as a good representation of mean aerosol composition and distribution. Concentrations of the same elements were also measured using stationary equipment near the ground level at the outskirts of Warsaw. The vertical profiles of element concentration were obtained and the elemental compositions for the tropospheric and stratospheric aerosols were compared with those from the near-ground level. Contribution of K, Ca, Ti and Fe, which are the main components of soil, in total mass of all detected ones was estimated. Relative concentrations of all measured elements, which show any differences in the composition of the aerosol were calculated. The results obtained confirm the fact that the stratospheric reservoir is observed in the bottom stratosphere. The XRF method based on molybdenum X-ray tube was used as an analytical tool in the determination of aerosols trace elements. The altitude distributions of radioactivity of 226 Ra and 210 Pb were determined using radiochemical methods.

The satellite and hypersatellite K X-ray lines emitted by sulphur projectiles (with energies 9.6, 16.0, 22.4, 32.0, 65, 79, 99 and 122 MeV) passing through carbon foils (with different thickness varying from 15 to 210 μg/cm2) have been measured using a Si(Li) detector. We use a theoretical model based on the single-configuration Dirac–Fock calculations and equilibrium charge state distribution to interpret the experimental K X-ray spectra parameters. For all projectile energies, we evaluate the probability of K-hole creation, the average population of L-shell, and the average population of the 3p and 4p subshells. In the case of 9.6–32.0 MeV beam energy we evaluate also the population of L and M shells of sulphur projectiles. For the energy range 65–122 MeV, we estimate the probability of appearance of the most important configurations. The lifetimes of the studied states is also deduced.

The paper discusses a nature of concentration distributions of trace elements in biomedical samples, which were measured by using the X-ray fluorescence techniques (XRF, TXRF). Our earlier observation, that the lognormal distribution well describes the measured concentration distribution is explained here on a more general ground. Particularly, the role of random multiplicative process, which models the concentration distributions of trace elements in biomedical samples, is discussed in detail. It is demonstrated that the lognormal distribution, appearing when the multiplicative process is driven by normal distribution, can be generalized to the so-called log-stable distribution. Such distribution describes the random multiplicative process, which is driven, instead of normal distribution, by more general stable distribution, being known as the Levy flights. The presented ideas are exemplified by the results ´ of the study of trace element concentration distributions in selected biomedical samples, obtained by using the conventional (XRF) and (TXRF) X-ray fluorescence methods. Particularly, the first observation of log-stable concentration distribution of trace elements is reported and discussed here in detail. 2003 Elsevier Science B.V. All rights reserved.

The total reflection X-ray fluorescence (TXRF) method was applied to study the influence of environmental pollution on the contents of trace elements in human full-term placenta and fetal membranes.The samples were collected from the donors living in two regions characterised by different levels of environmental pollution.In this comparative study, based on relatively large (;100) populations, the concentrations of approximately 20 trace elements (P-Pb) were determined in the samples.In particular, the paper discusses the role of 'truncation' of measured concentration distribution by the detection limit of the TXRF method in context of comparative studies. First, the importance of the developed method of reconstruction of original concentration distribution, to derive the correct concentrations of trace elements, is described and demonstrated and, second, the statistical tests, which can be used to compare the truncated, or reconstructed, concentration distributions are discussed.Finally, the statistically significant differences of trace element concentrations found in both populations are presented and summarised. 2002 Elsevier Science B.V. All rights reserved.

We examined the differences between the concentrations of chemical elements in caries-changed primary teeth and permanent ones with a division into the root and the crown. The study comprised 27 children aged from 4 to 11 yr and 36 adults aged from 36 to 71 yr. We examined the elements with the total reflection X-ray fluorescence method. The lowest concentrations of calcium, manganese, strontium, lead, and copper were in the roots of primary teeth compared to the roots of permanent ones. The calcium, nickel, zinc, lead, and copper concentrations were significantly higher in the roots of primary teeth than in the roots of permanent teeth. However, the zinc concentration was higher both in the root and crown of primary teeth than in permanent teeth. On the basis of our investigations, we can conclude that the content of some elements (manganese, copper, strontium, and lead) is higher in caries permanent teeth than in primary ones. The nickel and zinc concentrations are higher in the teeth of the children than the adults. However, the content of other elements (calcium, chromium, iron) is similar in both kinds of teeth.

A prospective randomized trial was used to determine iron concentrations in intestinal cancer tissue and colorectum polyps. We investigated the possible difference between the concentrations of iron, ferritin, albumin, and hemoglobin in the serum of patients with colorectal cancer and polyps. We also determined the relationship between the iron and ferritin levels in cancer tissue, the localization of neoplasms, and the stage of their development. The study comprises 67 patients with colorectum cancer and 42 patients with colon and rectum polyps. The metal was determined by using the total-reflection X-ray fluorescence (TRXRF) method. The mean concentration of iron in colorectal cancer equaled 46.1 microg/g of the tissue and was higher than in the case of polyps (43.2 microg/g). The mean serum iron level in patients with colorectal cancer was statistically lower than in the serum of patients with polyp and in the control group (54.5, 91.3, and 108.0 microg/g, respectively). The determined average concentration of ferritin in the serum of patients with colorectal cancer equaled 60.4 microg/g and was statistically lower than the level of this enzyme in the serum of patients with polyps (85.2 microg/g) and in the control group (102.0 microg/g). There was no difference between the serum albumin and hemoglobin concentrations in patients with colorectal cancer, polyps, and the control. There was no difference in the levels of iron and ferritin depending on the location of the neoplasm and the stage of its development. Also, there was no difference between the concentrations of iron in the cancer tissue of malignant and benign tumors after taking into consideration sex and age of patients. During the examination we determined significantly higher concentrations of iron in the cancer tissue and not in the polyp. The low levels of iron in the serum of patients with malignant tumor may increase colorectal cancer risk.

The method of analysis of the multiple ionization effects in low-resolution X-ray spectra induced by heavy ions is described here. It is shown that, by fitting the X-ray spectra measured by a semiconductor detector with the proposed model, which accounts for the multiple ionization effects, the ionization probabilities can be determined as free fitting parameters. This approach is based on the assumption that the intensity distribution of emitted X-ray satellites is approximately described by the binomial distribution parameterized by the ionization probability at the moment of X-ray emission. In particular, we demonstrate that the excited X-ray satellites, when measured by a low-resolution semiconductor detector, appear as the Gaussian profile, which is shifted and broadened with respect to the diagram line. Moreover, we find that both X-ray line shift and width are expressed in terms of the multiple ionization probabilities, as well as the X-ray energy shifts per vacancy. These observations allowed to develop a novel method of X-ray spectra fitting. Detailed discussion of the approximations used in the present approach is given. The method developed, using the calculated Dirac–Fock X-ray energy shifts per vacancy, was applied to determine the multiple ionization probabilities in M- and N-shell by fitting the measured X-ray spectra for L γ (L→N,O) transitions induced by heavy ions in selected high-Z atoms.

The systematic determination of trace-element concentrations in honey samples was done by the PIXE method using a 2 MeV proton beam and by the total reflection XRF method. The different kinds of honey samples were collected in the period of spring–summer in three places of Poland: in the centre of Warsaw (a highly polluted region) and about 100 km east of Warsaw and 70 km southwest of Warsaw (as regions free from industrial and transport pollution). The measured samples have shown that the concentrations of trace elements are similar in the honey samples from these places.

We investigated the possible differences between the concentrations of selenium in the whole blood and thyroid tissue of patients with thyroid disease. The study comprises 41 women with nodular goiter, 19 women and 2 men with thyroid cancer, 18 women with Graves' disease, and 7 women with thyroiditis. The concentration of selenium was determined by the TRXRF method. The lowest mean selenium level was achieved in the whole blood of women with Graves' disease and the highest in the whole blood of healthy people. In the thyroid cancer tissue, we found the lowest concentration of selenium and the highest in the thyroid gland of women with nodular goiter and Graves' disease. The low selenium levels in the thyroid tissue may increase thyroid cancer risk.

The results of a numerical simulation, performed to check the validity of a method developed for reconstruction of concentration distributions truncated by the detection limit, are reported in the context of trace element analysis in biomedical samples by total-reflection X-ray fluorescence. This method, by correcting a distribution over the whole range of concentrations in a population of samples, restores a number of measurements reporting results below the detection limit. We show by Monte Carlo simulations, assuming lognormal distributions to describe both the concentrations measured as well as the detection limits in the biomedical samples, that the method developed is accurate to within 5% for most typical situations. Moreover, we demonstrate that the factor limiting the accuracy of the correction is the number of measurements, not the correction procedure itself. We have found in simulations that the reconstruction of a concentration distribution, for a typical population size of N =100, is possible when the concentrations are measured only in 20–30% of samples. On the other hand, we show that by ignoring the truncation of a concentration distribution by the detection limit, the results can be systematically biased by as much as 50%. The method developed is applied to the analysis of trace elements in human breast tissue samples by total-reflection X-ray fluorescence (TXRF). The results are also discussed in terms of the size of the population studied.

The concentration distributions of trace elements in large populations (n > 100) of biomedical samples were studied by x-ray fluorescence spectrometry. For elements, the concentrations of which measured in all samples exceed the detection limit (DL) of the method, the log-normal distribution was found to describe the data very well. For other elements, measured in only a fraction of the studied population, the observed distributions were truncated by the variable DL level. We demonstrate, however, that by using the information on the distribution of reported detection limits, the original distributions of concentration, and also the detection limits, can be reconstructed from the measured data. This can be done by solving the system of integral equations relating the measured and original distributions of the concentration and the detection limit. The applicability of this method is demonstrated in a comparative study of trace element concentrations in urine samples. Copyright © 2001 John Wiley & Sons, Ltd.

Multiple ionization in outer M- and N-shells in Ta, Os, Au, Bi, Th and U targets was studied for O, Si and S ion impact at energies of 0.3-2.2 MeV amu-1. Excited Lγ(L-N, O) x-rays measured with a semiconductor Si(Li) detector were resolved by using a newly developed method accounting for simultaneous x-ray energy shift and line broadening due to the multiple ionization. The measured ionization probabilities, corrected for the effect of the vacancy rearrangement up to the moment of L x-ray emission, are interpreted as the ionization probabilities for M- and N-shells for the zero impact parameter. The ionization probabilities for the N-shell are found to be substantially increased by the super-Coster-Kronig transitions. Derived ionization probabilities for M- and N-shells are compared with the predictions of the geometrical model (GM) and the semiclassical (SCA) calculations in the united-atom limit. The universal scaling of the measured ionization probabilities for the M- and N-shells is discussed within the GM and SCA approaches.

Solid state effects for selected L–O(5p, 5d) X-ray transitions excited by O, Si and S ions of energies 0.4–2.0 MeV/amu are studied in metallic Os, Au, Bi, Th and U targets by measuring the L-X-rays with a semiconductor Si(Li) detector. Using the developed method of analysis of X-ray energy shifts and line broadening, combined with a change of the intensity-ratios, the ionization probabilities in M-, N- and O-shells during L γ X-ray emission were estimated. We found that the ionization probabilities measured in this way for M-, N- and O-shells are generally in good agreement with the theoretical predictions of the “geometrical model”, with the exception of L–O(5d) transition for the lighter (Os, Au and Bi) of the studied metals. We attribute this effect to the fast refilling of the 5d vacancies created in the collision by the delocalized valence band electrons. Such an effect is expected to be observed only when many electrons are removed from outer shells as a result of the multiple ionization.

Multiple ionization in M- and N-shells in solid Au, Bi, Th and U targets was studied for O, Si and S ions of energies 0.4–2.0 MeV/amu. L γ X-rays measured with semiconductor Si(Li) detector were analysed by using a newly developed method of the simultaneous determination of X-ray energy shifts and line broadening caused by the multiple ionization in outer shells. In this approach both X-ray energy shifts and widths are expressed in terms of ionization probabilities and calculated energy shifts per vacancy, allowing thus the unique fitting of the L γ X-rays and determination of ionization probabilities. Derived ionization probabilities for M- and N-shells exhibit universal scaling predicted by the geometrical model (GM) for the ionization probabilities at the zero impact parameter. The influence of time evolution of the vacancies formed in M- and N-shells by ion impact is discussed.

Concentrations of trace elements in biomedical samples were studied using X-ray fluorescence (XRF), total reflection X-ray fluorescence (TRXRF) and particle-induced X-ray emission (PIXE) methods. Used analytical methods were compared in terms of their detection limits and applicability for studying the trace elements in large populations of biomedical samples. In a result, the XRF and TRXRF methods were selected to be used for the trace element concentration measurements in the urine and woman full-term placenta samples. The measured trace element concentration distributions were found to be strongly asymmetric and described by the logarithmic–normal distribution. Such a distribution is expected for the random sequential process, which realistically models a level of trace elements in studied biomedical samples. The importance and consequences of this finding are discussed, especially in the context of comparison of the concentration measurements in different populations of biomedical samples.

Samples of malignant and benign human lung tissues were analysed by two complementary methods, i.e., particle induced X-ray emission (PIXE) and total reflection X-ray fluorescence (TRXRF). The concentration of trace elements of P, S, K, Ca, Ti, Cr, Mn, Fe, Cu, Zn, Se, Sr, Hg and Pb was determined in squamous cancer of lung tissue from 65 people and in the benign lung tumour tissue from 5 people. Several elements shows enhancement in cancerous lung tissue of women in comparison to men, i.e., titanium show maximum enhancement by 48% followed by Cr (20%) and Mn (36%). At the same time trace element concentration of Sr and Pb are declaimed by 30% and 20% in women population. Physical basis of used analytical methods, experimental set-up and the procedure of sample preparation are described.

The total reflection x-ray fluorescence method (TRXRF) has been employed to determine of P, S, K, Ca, Cr, Mn, Fe, Ni, Cu, Zn, Se, Rb, Sr, and Pb concentration in the benign breast tumor tissue from 68 women and in the cancerous breast tissue from 26 women. Concentrations of most of elements show enhancement in cancerous breast tissue. Examined elements compete for binding sites in the cell, change its enzymatic activity, and exert direct or indirect action on the carcinogenic process accelerating the growth of tumors. Inhibition of enzymatic activity caused by variation in trace element concentrations results in immunological breakdown of the body system. An attempt has been made to correlate measured trace element concentrations with the clinical stage of cancer. Physical bases of used analytical method, experimental setup, and the procedure of sample preparation are described.

A b s t r a c t. The effect of intensive irrigation with wastewater on the zinc (Zn) and cadmium (Cd) concentration in soil solution was investigated. The experiment was parallel conducted on two soil profiles. The soil microcosms were watered with purified wastewater and purified wastewater with an the addition of zinc and cadmium. The results indicate clearly that neither intensive overhead irrigation of the soil nor its flooding with these wastewater and exceeded sorptive capacity. The application of treated wastewater and wastewater with heavy metals addition did not appear to pose a threat to the natural environment. In all the cases under analysis, zinc and cadmium concentrations in the soil solution were several-fold lower than the permissible levels. K e y w o r d s: soil profile, wastewater, zinc, cadmium

In the present work, an alternative approach for the evaluation of the equilibrium K-, L-, and M-shell ionizations and the mean charge state q for projectiles passing through various targets has been proposed. The approach is based on measured K x-ray energy shifts and line intensity ratios and utilizes the theoretical analysis of projectile spectra using multiconfiguration Dirac-Fock calculations. It was applied for the satellite and hypersatellite K lines in the x-ray spectra emitted by sulfur projectiles passing with energies of 9.6-122 MeV through carbon, aluminium, titanium, and iron targets, recorded by a Si(Li) detector. It was found that only in the high projectile energy region there was significant dependence of mean equilibrium K-shell ionization on the target atomic number. The equilibrium L-shell ionization rises with the increase of sulfur energy until 32 MeV, but for higher energies the changes are very weak. The equilibrium M-shell ionization changes very weakly for low projectile energy while for higher energies this ionization is practically constant. For each target, the estimated value of q rises with the increase of the sulfur energy value. The dependence of the sulfur charge state on the target atomic number was discussed by taking into account the crossmore » sections for ionization, decay, and electron capture processes. The data were compared with the experimental data measured by other authors and with the predictions of Shima's and Schiwietz and Grande's semiempirical formulas. The presented good agreement points out that this alternative approach delivers quantitative results.« less

The coupling and binding effects have been studied in $L$-subshell ionization of heavy Au, Bi, Th, and U atoms by an impact of ${^{28}\text{S}\text{i}}^{q+}$ ions in the energy range of 8.5--36.0 MeV. The measured $\mathit{L}$ x-ray spectra were analyzed taking into account the multiple ionization effects in outer $M$ and $N$ shells. The $L$-subshell ionization cross sections have been obtained from measured x-ray production cross sections using the $L$-shell fluorescence and Coster-Kronig yields which were modified for a reduced number of electrons and closed Coster-Kronig transitions in the multiply ionized atoms. The results are compared with the available calculations, which are based on the semiclassical approximation (SCA) as well as the plane-wave Born approximation (PWBA). We demonstrate that for silicon ion impact these theoretical approaches have to be modified to include the $L$-subshell coupling effect using the ``coupled subshell model'' (CSM) as well as the saturation of the binding effect at the united atom limit. The calculations modified for both effects are in much better agreement with the data. In particular, an order-of-magnitude improvement of agreement between the data and the SCA-CSM calculations including the binding-saturation effect is reported for low-energy Si ions for the ${L}_{2}$-subshell. The results are also compared with the predictions of the PWBA based ECPSSR and ECUSAR theories accounting for the energy-loss (E), Coulomb-deflection (C), and relativistic (R) effects treating the binding effect within the perturbed stationary state (PSS) approximation with correction for the binding-saturation effect introduced to describe the united-atom and separated-atom (USA) limits.

The concentrations of Fe, Cu, Zn and Se in cancerous and benign tissues of breast, lung and intestine (colon) have been determined. In the cases when the element concentration has not been determined in all samples the Kaplan-Meier method has been used for the reconstruction of the original concentration distributions and estimation of the true mean concentrations and medians. Finally, the log-rank test has been applied to compare the elemental concentration distributions between cancerous and benign tissues of the same organ, between cancerous tissues and between benign tissues taken from different organs. Comparing benign and malignant neoplastic tissues, statistically significant differences have been found between Fe and Se concentration distributions of breast as well as for Cu and Zn in the case of lung tissues and in the case of colon tissues for Zn. The concentrations of all elements have been found to be statistically different in cancer tissues as well as in benign ones when comparing the different organs, i.e. groups 'breast-colon' and 'breast-lung'. Concentrations of Fe and Cu have been found to be statistically different in lung and colon cancerous tissues. For benign tissues of lung and colon a statistically significant difference has been found only for Zn.

The K{alpha} and K{beta} satellite and hypersatellite x-ray lines emitted by highly ionized sulfur projectiles passing with energies from 65 MeV up to 122 MeV through carbon foils of thickness of 15-210 {mu}g cm{sup -2} have been recorded using a Si(Li) detector. The additional hypersatellite Ky{sup h} peak proves that for such high energies of the sulfur ions very high subshells (4p and 5p) could be occupied. In order to study the dynamics of formation of K-shell vacancy fractions of sulfur projectiles passing through a carbon foil the dependence of sulfur K x-ray production cross sections on foil thickness has been examined separately for each recorded line using the three component model. For each projectile energy the values of K-shell hole production cross sections and K-shell electron capture cross sections (both common for all recorded x-ray lines in the case of each projectile energy) have been fitted, as well as the specific values (for each recorded x-ray line) of K-shell hole filling cross sections, which are directly connected with average lifetimes of appropriate states of sulfur ions. The obtained ''experimental'' values of K-shell vacancy production cross sections are much higher than the theoretical predictions. This suggests that apart from themore » ionization process the excitation from K shell into higher shells is responsible for a production of K-shell vacancies, which has been confirmed by recent classical trajectory Monte Carlo calculations.« less

The multiple-ionization and coupling effects in L-shell ionization of atoms by heavy-ion impact have been studied by measuring the L x-ray production cross sections in solid targets of Au, Bi, Th, and U bombarded by oxygen ions in the energy range 6.4--70 MeV. The measured L x-ray spectra were analyzed using the recently proposed method accounting for the multiple-ionization effects, such as x-ray line shifting and broadening, which enables one to obtain the ionization probabilities for outer shells. The L-subshell ionization cross sections have been obtained from measured x-ray production cross sections for resolved $L{\ensuremath{\alpha}}_{1,2},$ $L{\ensuremath{\gamma}}_{1},$ and $L{\ensuremath{\gamma}}_{2,3}$ transitions using the L-shell fluorescence and Coster-Kronig yields being substantially modified by the multiple ionization in the M and N shells. In particular, the effect of closing of strong ${L}_{1}\ensuremath{-}{L}_{3}{M}_{4,5}$ Coster-Kronig transitions in multiple-ionized atoms was evidenced and discussed. The experimental ionization cross sections for the ${L}_{1},$ ${L}_{2},$ and ${L}_{3}$ subshells have been compared with the predictions of the semiclassical approximation (SCA) and the ECPSSR theory that includes the corrections for the binding-polarization effect within the perturbed stationary states approximation, the projecticle energy loss, and Coulomb deflection effects as well as the relativistic description of inner-shell electrons. These approaches were further modified to include the L-subshell couplings within the ``coupled-subshell model'' (CSM). Both approaches, when modified for the coupling effects, are in better agreement with the data. Particularly, the predictions of the SCA-CSM calculations reproduce the experimental L-subshell ionization cross section reasonably well. Remaining discrepancies are discussed qualitatively, in terms of further modifications of the L-shell decay rates caused by a change of electronic wave functions in multiple-ionized atoms.

The Zn concentration in thyroid tissue and whole blood of patients with Graves' disease, thyroid cancer, and nodular goiter disease was determined using the total-reflection X-ray fluorescence method. The dependence of obtained concentrations on the clinical stage of the examined disease, histopathological grading, and kind of analyzed material (thyroid tissue and blood) was studied. The determined concentration of Zn was the lowest in the thyroid tissue of patients with thyroid cancer (23.1 microg/g) and it was the highest in the case of Graves' disease (41.7 microg/g), whereas in the blood samples, the reverse results were found (7.1 microg/g and 4.8 microg/g, respectively). The physical basis of the method used, the experimental setup, and the procedure of sample preparation are described.

Multiple ionization in M-, N- and O-shells in solid Au, Bi, Th and U targets was studied for Oq+, Siq+ and Sq+ ions of energies 0.4–2 MeV/amu under charge equilibration condition. From L-x-rays, detected by Si(Li) detector, the ionization probabilities for M- and N-shells were derived. This was done by fitting the measured spectra using a developed model, which describes x-ray energy shifts and line broadening in terms of the ionization probabilities. Derived ionization probabilities are compared with the predictions of the geometrical model (GM). For M- and N-shell the data agree quite well with calculations. The ionization probabilities for O-shell, estimated from line intensity ratios, are in strong disagreement with theoretical predictions, indicating an influence of solid state effects. An importance of multiple ionization effects on derivation of L-subshell ionization cross sections is evidenced and discussed.

The study was aimed at evaluation of iodized salt consumption, urinary iodine concentration and incidence of goiter in children from four districts of north-western Poland: Szczecin, Koszalin, Słupsk and Gorzów Wlkp. The study was a part of the national programme: "Investigations of iodine deficite and iodine prophylaxis in Poland". The investigations were performed in ten schools randomly selected by Coordinating Centre in Kraków. Altogether 1793 children attending these schools (838 boys and 955 girls) of age between 6 ad 13 years, living in the cities and villages of coastal and lowland region were studied. The examination included interview in the form of a standard questionnaire, physical examination of the thyroid according to the WHO criteria, ultrasonographic evaluation of thyroid volume and determination of iodine concentration in single urine specimen. It appeared that only 11.2% of children used to consume iodized salt. Mean iodine concentration in urine was 76.2 micrograms/l both in children consuming and not consuming iodized salt, indicating dietary iodine deficiency. The incidence of goiter in country population of children (12.9%), indicated that the region of north-western Poland should be considered as an area of mild goiter endemy. These results suggest a need for iodine supplementation of edible salt in this region of Poland.

The chemotherapy and photon radiotherapy are the most often applied methods in treatment of the cancer diseases because of their effectiveness and high cure rates. Apart from eligible destruction of the tumour, one of the side effects of these treatment methods is possible modification of main and trace element concentration in different human tissues and fluids. In this paper, the copper (Cu) level in human serum was determined by total reflection X-ray fluorescence method in 142 chemotherapy patients and in 44 healthy persons being a control group. The Cu concentration in the chemotherapy group was found to be on the level 1.78 ± 0.909 mg/L, while in the control group, it was 1.08 ± 0.551 mg/L. Performed measurements allowed for calculation of the parameters of copper concentration distribution (mean value, standard deviation, median) for both analysed groups. The theoretical nature of the concentration distribution was tested and found as a log-normal distribution (control group) and a log-stable distribution (chemotherapy group). The copper concentration distributions for both studied group were statistically compared using Kolmogorov-Smirnov test, and the conclusion was that the distributions are statistically different. Serum Cu levels were significantly higher in the chemotherapy group than in the control group. Taking into account the results for the control group, the copper concentration reference quantile ranges in human serum were obtained. The values of the mean, median and other quantiles determined in this case can be applied in two-group comparison studies. The obtained results can be used as a diagnostic tool for chemotherapy patients.