Trace elements of soil samples from mining area

The affect of mining activity on the environment has been long of public concern. The present paper deals with the elemental analysis of soil samples from a mine and the area around it, located in E 48°59′ and N 34°11′ in Hamadan province of Iran. Elemental analysis was done using Proton Induced X-ray Emission (PIXE) technique. Spectra analysis and quantification was done using GUPIX software. Besides the major elements Si, P, K, Ca, Mn and Fe the other elements, namely Cl, Ti, V, Cr, Co, Ni, Cu, Zn, Rb, Sr and Pb were also present. Arsenic could be detected in some samples only. The presence of Ba and Ce needs more investigations by other techniques due to overlap of the L X-rays of these elements with the K X-rays of the major elements Mn and Fe, etc. Many elements V, Cr, As and Pb are known to be toxic and needs further understanding and proper handling in the mining process.     

Trace elements in lake sediments measured by the PIXE technique

Lakes are ecosystems where there is a great potential of metal accumulation in sediments due to their depositional characteristics. Total concentration of trace elements was measured on a 50 cm long sediment core from the Infernão Lake, that is an oxbow lake of the Moji-Guaçu River basin, in the state of São Paulo, Brazil. Dating of the core shows up to 180 yrs old sediment layers. The use of the PIXE technique for elemental analysis avoids the traditional acid digestion procedure common in other techniques. The multielemental characteristic of PIXE allows a simultaneous determination of about 20 elements in the sediment samples, such as, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Rb, Sr, Zr, Ba, and Pb. Average values for the elemental composition were found to be similar to the bulk crustal composition. The lake flooding pattern strongly influences the time series of the elemental profiles. Factor analysis of the elemental variability shows five factors. Two of the factors represent the mineralogical matrix, and others represent the organic component, a factor with lead, and another loaded with chromium. The mineralogical component consists of elements such as, Fe, Al, V, Ti, Mn, Ni, K, Zr, Sr, Cu and Zn. The variability of Si is explained by two distinct factors, because it is influenced by two different sources, aluminum-silicates and quartz, and the effect of inundation are different for each other. The organic matter is strongly associated with calcium, and also bounded with S, Zn, Cu and P. Lead and chromium appears as separated factors, although it is not clear the evidences for their anthropogenic origin. The techniques developed for sample preparation and PIXE analysis was proven as advantageous and provided very good reproducibility and accuracy.     

Brain trace elements and aging

Degenerative mechanisms involved in the aging process of the brain are to a certain extent counteracted by repair mechanisms. In both degenerative and recovery processes, trace elements are involved. The present study focused on the role of two minor (i.e., K and Ca) and six trace elements (i.e., Mn, Fe, Cu, Zn, Se and Rb) in the aging process. The elements were determined by PIXE in cerebral cortex and white matter, basal ganglia, brainstem and cerebellar cortex of 18 postmortem human brains, from persons without a history of neurologic or psychiatric disease who deceased between the age of 7 and 79. This age range allowed us to study the relationship between elemental concentrations and age. The most prominent findings were a concentration decrease for K and Rb and a concentration increase for the elements Ca, Fe, Zn and Se. The study supports recent findings that Ca and Fe are involved in brain degenerative processes initiated by oxygen free radicals, whereas Zn and Se are involved in immunological reactions counteracting the aging process.     

Roadside dust contamination with toxic metals along industrial area in Islamabad,Pakistan

An investigation has been carried out to understand the contamination characteristics of roadside dust in the industrial area of Islamabad, Pakistan. The amounts of Si, S, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Pb, Zn, Ga, As, Se and Cd were determined from 95 roadside dust samples collected along the Islamabad industrial area using Proton Induced X-ray Emission （PIXE）. The results indicated that concentrations of all elements, except Cd, in the roadside dust were significant. The results of the enrichment factor show that the elementary composition of the roadside dust could be categorized as soil elements from the crust of the earth and elements from anthropogenic pollution. The high enrichment factors imply that elements such Cr, Cu, Pb, Zn, As, Se, Cd, Ni, Co and S came from anthropogenic activities. The source of metal contamination was identified using multivariate statistical analysis. It has been concluded that Ca, Sc, Ti, V, Mn and Fe mainly originate from crustal sources; Cr, Cu, Ni, Pb, Zn and Ga are associated with point-sources from industrial pollution/traffic; and S, Cl, K, As and Se are mainly related to oil/coal combustion.     

股骨头松质骨中无机元素的PIXE分析

使用质子激发Ｘ射线荧光分析技术测定了５例正常人和７例股骨颈骨折患者股骨头松质骨中无机元素谱的分布。详细介绍了骨样品处理技术，建立了正确测定骨骼微量元素的定量方法。结果表明在对照组中元素Ｐ、Ｃａ、Ｆｅ、Ｃｕ、Ｓｒ的含量高于病变组，统计检验表明有显著意义，而元素Ｓ、Ｋ、Ｍｎ、Ｚｎ在两组间无显著差异。对Ｃａ、Ｐ、Ｓｒ、Ｃｕ等无机元素的生理功能进行了初步的讨论。     

Internal elemental imaging by scanning X-ray fluorescence microtomography at the hard X-ray microprobe beamline of the SSRF: Preliminary experimental results

Synchrotron-based X-ray micro-fluorescence (μ-SXRF) is a non-destructive analytical technique and has been widely used to detect and quantify the elemental composition of samples in their natural state. To determine the internal elemental distributions within samples, X-ray fluorescence microtomography has been developed based on the hard X-ray microprobe at beamline BL15U1 of the Shanghai Synchrotron Radiation Facility (SSRF) in Shanghai, China. This technique was applied to image the cross-sectional distributions of multiple elements within a single human hair, and its validity was evaluated by comparing the results with the elemental maps of a thin hair section obtained using the well-established μ-SXRF mapping method. Elemental images of S, Ca, Mn, Fe, Cu, and Zn within a virtual slice of the hair were reconstructed after the tomographic measurements. The tomographic images of heavy elements like Fe, Cu, and Zn were found to be in good agreement with the corresponding μ-SXRF maps. Light elements, such as S, however, represented different patterns due to non-negligible self-absorption in the sample, and sophisticated correction algorithms accounting for such effects are required for obtaining qualitatively and quantitatively more accurate images. Compared to μ-SXRF mapping, X-ray fluorescence microtomography reduces the sample preparation requirements and has been demonstrated in this work as being a more ideal and effective imaging modality to non-destructively mapping out the internal distribution of heavy elements within samples at the micrometer scale at the SSRF.     

Analysis of lichen thin sections by PIXE and STIM using a proton microprobe

In order to better understand the distribution pattern of mineral elements in lichen tissues, thin sections (15 μm) of the foliose, vagrant soil lichen Xanthoparmelia chlorochroa were examined using proton microprobe Particle induced X-ray emission (PIXE). This technique was used to make two-dimensional scans, with 5 μm resolution, across tissue cross sections of the test species. Element maps for Si, P, S, Cl, K, Ca, Ti, Mn, Fe, Cu, Zn, and As have been prepared. Several elements are strongly localized in the element maps. PIXE data are complimented with STIM, light micrographs, and SEM images. Preliminary data suggest that nuclear microprobe techniques may be useful in elucidating element absorption and transport mechanisms in lichens.     

Evaluation of elemental status of ancient human bone samples from Northeastern Hungary dated to the 10th century AD by XRF

The present study is a multielemental analysis of bone samples belonging to skeletal individuals originating from two contemporaneous (10th century AD) cemeteries (Tiszavasvári Nagy-Gyepáros and Nagycserkesz-Nádasibokor sites) in Northeastern Hungary, using the XRF analytical technique. Emitted X-rays were detected in order to determine the elemental composition of bones and to appreciate the possible influence of the burial environment on the elemental content of the human skeletal remains. Lumbar vertebral bodies were used for analysis. Applying the ED(P)XRF technique concentration of the following elements were determined: P, Ca, K, Na, Mg, Al, Cl, Mn, Fe, Zn, Br and Sr. The results indicated post mortem mineral exchange between the burial environment (soil) and bones (e.g. the enhanced levels of Fe and Mn) and referred to diagenetic alteration processes during burials. However, other elements such as Zn, Sr and Br seemed to be accumulated during the past life. On the basis of statistical analysis, clear separation could not be observed between the two excavation sites in their bone elemental concentrations which denoted similar diagenetic influences, environmental conditions. The enhanced levels of Sr might be connected with the past dietary habits, especially consumption of plant food.     

骨骼样品PIXE分析测定方法研究

简单介绍用内标法测定骨骼样品中微量元素的制样方法，特别是复合吸收片的方法，可克服主量元素Ｐ和Ｃａ对微量元素的影响，使骨骼样品的质子激发Ｘ荧光分析法（ＰＩＸＥ）能谱中微量元素Ｓ、Ｋ、Ｓｃ、Ｖ、Ｃｒ、Ｍｎ、Ｃｏ、Ｃｕ、Ｚｎ的能峰清晰、突出，为定量分析奠定了基础。微量元素Ｆｅ和Ｓｒ的相对规一含量在骨折愈合过程中分别呈鼓凸形和下凹形规则性变化。     

补碘和硒对克汀鼠红血球中的微量元素的影响

用克汀病流行病区的粮食喂养大鼠（克汀鼠）,分成4个组补硒、补碘、补碘同时补硒、和作为对照的低碘鼠,另取一正常对照组。补充5周后,用PIXE法和测量它们红血球的微量元素（K、Ca、Mn、Fe、Cr、Cu、Zn、Rb、Pb等）。用放射性免疫法测定甲状腺激素指标（T3、T4、FT3、FT4、rT3等）。获得的数据用SPSS／PC单因素方差分析和相关检验。结果表明,低碘鼠补碘、硒或同时补碘硒后,Zn、Mn、Cu和Rb的含量变化以及甲状腺激素指标T4、FT4和rT3比低碘鼠显著地升高。     

PIXE analysis of trace elements in northern fur seal teeth

Trace elements in teeth of northern fur seal Collorhinus ursinus were analyzed by PIXE and micro-PIXE (μ-PIXE). Trace elements such as Mn, Fe, Zn, Cu, As, Br, Sr, and Pb were detected in the teeth, which were composed of hydroxyapatite crystals. Among these elements, the concentrations of Fe and Zn were relatively higher in winter and lower in summer and also Zn varied along with growth of individuals. These elemental fluctuation seems to correspond to the life history of the northern fur seal. It suggests that the PIXE analysis will make a powerful tool to reconstruct the life history.     

Analysis of blood and tissue in gallbladder cancer

Particle induced X-ray emission, particle induced γ-ray emission studies has been carried out to analyse normal and carcinoma tissues and blood samples of gallbladder of both sexes and seventeen trace elements namely Na, Mg, Al, K, Ca, Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br and Pb were estimated in the tissue and blood samples. In the present study, concentration of Zn in the carcinoma gallbladder tissue is less than that of the normal gallbladder tissue. Tobacco habit could be one of the important factors to decrease the elemental concentrations in blood and tissue samples.     

用计算机模式识别法和PIXE法研究人发中元素在食管癌诊断中的作用

用ＰＩＸＥ方法对华北地区的４１４例食管癌、食管上皮重度增生病人和正常人的头发样品中的１２种元素进行了测定。经过ｔ检验发现，癌症病人与正常人比较，１０种元素（Ｓｉ，Ｓ，Ｃａ，Ｃｒ，Ｍｎ，Ｆｅ，Ｎｉ，Ｃｕ，Ｐｂ，Ｓｒ）有显著差异；食管上皮重度增生病人和正常人比较，９种元素（Ｓｉ，Ｐ，Ｓ，Ｃａ，Ｃｒ，Ｍｎ，Ｆｅ，Ｎｉ，Ｚｎ）有显著差异，说明头发中微量元素的变化先于人体内食管的癌变。用计算机模式识别法对上     

Elemental and topographic characterization of LDPE based copolymeric films obtained by gamma irradiation

The preparation of PE-g-HEMA (polyethylene-grafted-hydroxyethyl methacrylate) films by ⁶⁰Co gamma irradiation has been optimized to produce a new material suitable for bioapplications.This paper reports the elemental and topographic analysis of PE-g-HEMA films with different grafting degrees, obtained under optimized experimental conditions, with the purpose to appraise their possible toxicological risk and their surface roughness properties.In this way a Nuclear Microprobe using PIXE (Proton Induced X-ray Emission) technique was used to assess the elemental analysis of the film samples prepared. Trace contaminations of elements heavier than Si (Ca, Cl, Fe, K, P, S, Si and Zn) were found, but their concentrations do not pose toxicological risk.Atomic Force Microscopy (AFM) and Scanning Electronic Microscopy (SEM) techniques were used to assess the morphological characterization of the films, revealing the roughness and 3D porous structure of their surface, which are ones of essential characteristics for bio-interaction or cell adhesion.     

PIXE investigation of aerosol composition over the Zambian Copperbelt

Atmospheric sulphate aerosol concentrations are of interest in climate change studies because of their negative climate forcing potential. Quantification of their forcing strength requires the compilation of global sulphur emission inventories to determine the magnitude of regional sources. We report on measurements of the ambient aerosol concentrations in proximity to a copper refinery in the central African Copperbelt, along the border of Zambia and the Democratic Republic of the Congo. This region is historically regarded as one of the largest African sources of sulphate aerosols. Sulphate is produced by oxidation in the atmosphere of SO₂ emitted during the pyrometallurgical processing of Cu–Co sulphide ores. Since the last quantification of sulphur emissions (late 1960s), there has been large-scale reduction in copper production and more frequent use of the leaching technique with negligible sulphur emissions.

Samples were collected over four weeks, November–December 1996, at Kitwe, Zambia. A low volume two-stage time-resolving aerosol sampler (streaker) was used. Coarse and fine mode aerosols were separated at >2.5 and >10 μmad. Hourly elemental concentrations were determined by 3.2 MeV PIXE, and routinely yielded Si, S, K, Ca, Ti, Mn, Fe, Cu and Zn, above detection limits. Si, K, Ca and Fe (major crustal components) dominated the coarse elemental mass. In the fine stage, S and Si accounted for up to 80% of the measured mass, and S alone up to 60%. Time series analysis allowed the division of sulphur and crustal elements (Si, K, Ca, Fe) between (i) background concentrations representative of synoptic scale air masses; and (ii) contributions from local sources, i.e., copper smelter and re-suspended soil dust. Short duration episodes of S concentrations, up to 26 μg/m³, were found simultaneously with enhanced Cu, Fe and Zn. Contributions from individual pyrometallurgic processes and the cobalt slag dump could be distinguished from the elemental signatures. Periods of diminished sulphur concentrations were also identified, indicating a well-mixed regional air mass. These results will contribute towards validating global climate model predictions of aerosol forcing over central Africa.     

Biomonitoring study of seasonal anthropogenic influence at the Itamambuca beach (SP, Brazil)

The present work is focused on the study of a seasonal anthropogenic influence on the beach of Itamambuca (Ubatuba, SP, Brazil) carried out using Atherinella brasiliensis as biomonitor. In total 84 fish were caught between July 2004 and February 2005 in different locations at the beach and inside the Itamambuca river. The fish were pooled according to catch and their musculature was analyzed by Particle-Induced X-ray Emission (PIXE) and Rutherford Backscattering (RBS) techniques. While the concentration of light (matrix) elements like C and O were obtained using the RBS technique, major (Na, Mg, P, S, Cl, K and Ca) and trace (Si, Al, Ti, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Br and Sr) elements were measured by PIXE. The results show that differences were observed for several elemental concentrations of fish tissue between high season (spring-summer) and low season (winter-fall), indicating that increased human activity in the beach during high season may have some impact on the beach ecosystem. The role of the water salinity in the results is also discussed.     

Thick target PIXE analyses of the elemental distributions across the surface and inside human fingernails

The energy dispersive spectrometry of thick target proton-induced X-ray emission (thick target PIXE) was used to determine the distributions of 11 elements (S, Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn) across the surface and at a certain depth inside human fingernails. The respective profiles are discussed and preliminary interpretations are given. The results are compared with data from other authors.     

Quantitative micro-PIXE mapping of squid statoliths

Distribution of elements in statoliths of squid Loligo vulgaris reynaudii d'Orbigny, 1845 was studied, using the true elemental imaging system (Dynamic Analysis) of the NAC nuclear microprobe. The analysis revealed various patterns of Ca and Sr distributions. The biological interpretation of the most frequent pattern is linked with the role of Sr in the statolith deposition process. Other patterns are linked with the technique used and the specific characteristics of the sample. Traces of other elements (Cr, Mn, Fe, Cu, Zn, Br, Pb) were also found. Likewise, their presence may have the biological interpretation (Zn, Cu and Br), or is an artefact linked to the methods and conditions of sample preparation and/or analysis. Methodical aspects of using proton backscattering for PIXE X-ray yield corrections are also discussed.