Proton Induced X-ray Emission Technique Research Articles

Correlation between nutrients, rare earth elements and heavy metals in O. Sativa rice plant organs by instrumentation neutron activation analysis and proton induced x-ray emission techniques

The accumulation of halogens and metals from roots to stems, leaves and grains of Oryza sativa rice plant collected in Northern Senegal (St Louis region) at the same stages of growth but at different salinity soil levels was investigated by measuring their elemental concentration by invasive instrumental techniques of neutron activation analysis and proton induced x-ray emission. The normalized elemental concentration of Na, Cl, K, (Cs, Rb, Sr, Sb, Ba Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Cu, Zn, As, Se, Br, Rb, Sb was correlated with one of rare earth elements, La, Ce, Sm, Yb, Nd, Eu, Tb, Tm, and Lu) and the one of the heavy metals Hf, Ta and Th and to assess their subsequent distribution within the Oryza sativa rice plant in a particular salinity environment. The exploration of the experimental data was performed by applying machine learning techniques with Python to find their elemental correlations. This study shows that the accumulation of iron is highly correlated with the amount of rare earth elements and heavy metals investigated. We observe an inverse correlation between Fe and Cl concentrations in the roots and stems of the Oryza sativa rice plant, in which higher levels of Fe in the roots relative to stems correspond to lower levels of Cl. We also remark that there is no accumulation of rare earth elements in the root tissues of the different Oryza sativa rice plants studied. Whereas, in the stem, leaf, and grain organs there is a strong correlation between metal contents and rare earth elements.

Heavy Metals Accumulation in Vegetables and Its Consequences on Human Health in the Areas Influenced by Industrial Activities.

The degradation of the environment due to numerous industrial practices has emerged as a major issue globally, particularly in a country like Bangladesh. The present study dispenses information about heavy metal (Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, and Pb) contamination in some frequently consumed vegetables, namely, ash pumpkin, potato, bitter gourd, buffalo spinach, snake gourd, and pointed gourd grown in an industrially prone location and their repercussion on consumers' health. Proton-induced X-ray emission (PIXE) technique was used as the major analytical tool to detect heavy metal concentrations. Mean concentration and the range of Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, and Pb in vegetables were detected (4.81 ± 2.79, 2.43-10.94), (497.57 ± 258.08, 181.24-886.67), (644.49 ± 298.40, 179.56-998.78), (38.88 ± 14.31, 18.88-60.12), (58.11 ± 12.58, 42.55-84.79), (137.24 ± 48.37, 71.99-208.98), (123.31 ± 63.62, 49.97-256.09), (8.09 ± 2.69, 4.29-14.94), and (4.16 ± 2.95, 1.22-9.98) mg/kg (dry weight basis), respectively. An extreme level of heavy metal contamination in vegetable samples was notified regarding the estimated metal pollution index (MPI) and Nemerow pollution index (P) value, which underpinned the health risk values. The estimated hazard index (HI) value stipulated high risk in all varieties of vegetables regardless of age group and cadmium (Cd) was found as the major contributor. Concerning the carcinogenic risk index (CR) for single elements, the value of Co, Ni, and Cr was approximated far above the USEPA threshold risk limit (CR>1E-04). Moreover, total carcinogenic risk (TCR) for all varieties of vegetables exceeded the safety threshold value for both the age group and children, in particular, were found most vulnerable. The outshot of the present study divulged associated health risks for the population group by the heavy metals via dietary intake of vegetables.

Soil contamination and health risk assessment at coastal Upazilas of the Bangladesh: a case study

ABSTRACT The present study analyzed soil samples from flood-prone Unions in two Coastal Upazilas of Bangladesh using Proton Induced X-Ray Emission (PIXE) techniques with Van de Graaff Accelerator for detecting heavy trace elements and Gamma spectrometry techniques. The findings indicate that while Potassium (averaging 19,62 μg/g for Sutarkhali; 21364.67 μg/g for Amtoli) and Calcium (averaging 36,923.92 μg/g for Sutarkhali; 30404.33 μg/g for Amtoli) levels were high naturally, the levels of Lead (averaging 71.8 μg/g for Sutarkhali; 171.44 μg/g for Amtoli), and Chromium (averaging 6.87 μg/g for Sutarkhali; 340.22 μg/g for Amtoli) were posing a serious risk to the inhabitants. The evaluation contamination factor (CF), pollution load index (PLI), potential ecological risk index (ERI) and health risk assessment indicate severe heavy metal pollution in both regions, with young children being particularly vulnerable to lead poisoning. Nonetheless, the radiation levels were below the safe limit set by the International Atomic Energy Agency (IAEA).

Analysis of the distribution of titanium oxide nanoparticles on paintings

Abstract This work is addressed to analyse the distribution of titanium dioxide nanoparticles on painting crossing data coming from two methodologies. Scanning Electron Microscope and Proton Induced X-Ray emission techniques have been employed in the study of the interaction between a colloidal dispersion constituted by titanium dioxide nanoparticles and the painting surface. The former e was used to understand and morphology of the painting and to investigate the distribution of the nanoparticles on the entire cross section of the pictorial layers. Proton induced X-ray emission is aimed at examining the surface titanium distribution by mapping. This study is important because the exploitation of the photocatalytic activity of the titanium dioxide is possible only in the case of absorption of proper energy that can promote the oxide reduction reactions and thus the dirt and dust degradation.

Analytical result of charnockites by PIXE and its comparison with other analytical technique XRF

The results of geochemical analysis of elements in matrix geological materials like charnockites by using the Proton Induced X-ray Emission technique are compared with other previous analytic results of X-Ray Fluorescence. In this investigation, PIXE has been used for elemental analysis of a variety of charnockite rocks in the form of a high-grade matrix at Charnockite hill, Eastern Ghats AP, India. The elemental concentrations in charnockites by using the present PIXE technique for multi elemental analysis are discussed from a previous study XRF of the exterior part of the charnockite analysis. The merits, limitations, and other factors of the experiments related to PIXE and XRF techniques in the case of elemental analysis of charnockite rock have been reviewed.

Element profiling of thirty genotypes of yam bean in eastern India by using proton induced X-ray emission (PIXE)

Yam bean (Pachyrizhus erosus L. Urban) is an underutilized tuberous legume crop having a good source of vitamins, minerals, sugar, and dietary fiber for human health. The implication of Proton-induced X-ray emission (PIXE) technique helped in determining the amount of nutrients availability in thirty yam bean genotypes. Certain minor and trace element concentration were identified and quantified in yam bean genotypes as P, S, K, Ca, Ti, Mn, Fe, Ni, Cu, Zn, Rb and Sr by using the software package named GUPIX-2000. PIXE measurements were carried out with 3 Me V proton beams with 20 nA beam current on target for element analysis. In the present study, highest quantity of elements such as K (30000 mg Kg−1), Ca (2040 mg Kg−1), Mn (129 mg Kg−1), Cu (18.5 mg Kg−1), Zn (29.4 mg Kg−1), Rb (63.1 mg Kg−1), and Sr (9.74 mg Kg−1) were found in genotype YBBL-20, whereas the highest content of P (9680 mg Kg−1), S (3600 mg Kg−1) and Ni (28.2 mg Kg−1), Fe (395 mg Kg−1), and Ti (35.2 mg Kg−1) was found in EC100549, YBBL-2, EC100567, and EC100551 respectively. This study could be helpful in identifying the nutrition/mineral rich element genotypes and also in providing the nutritional security to the developing countries like India.

Ion Beam Analysis of Proton-Induced X-ray Emission (PIXE) Techniques for Elemental Investigation of Young Stage Neem Leaf of Southern India, Tamil Nadu.

Young stage neem leaf (Azadirachta indica) was collected at Thiruvallur district in Tamil Nadu, South India. Multi-elemental analysis of neem leaf was carried out using non-destructive techniques (NDT) of proton-induced X-ray emission (PIXE, 2.5MeV) which is one of the well-known surface chemical sophisticated analytical methods of ion beam analyses (IBA). From the emitted X-ray output of the target specimen specimen fingerprint multi-elements such as, aluminium (Al), silicon (Si), phosphorus (P), sulphur (S), chloride (Cl), potassium (K), calcium (Ca), titanium (Ti), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn) and strontium (Sr) are found to be present in the leaf in different ppm levels. Among the elements, silicon (Si, 42034+1198.0ppm) and potassium (K, 28985+747.8ppm) showed the highest concentration. Minor elements (Mn, Sr, Fe, Zn, Cu and Ti) are observed in the neem plant. The variation in elemental concentration in the leaf may be due to soil, water, etc. However, there are no toxic elements observed like arsenic and lead in the leaf.Further, though the presence of different medicinal values in the target specimen chemical multi-elements observed in ppm level. However, there aremore chemical analysis to be required for the functionalization of active biomedical applications for these kinds of medicinal species.

Positron Annihilation Spectroscopy of KCl (Zn) crystals

Four samples of nominally pure KCl crystals and doped with Zn2+ impurities are grown by the Czochralski method and characterized by X-ray diffraction and Proton Induced X-ray Emission techniques. Positron Annihilation Lifetime Spectroscopy (PALS) is performed to obtain information on the cation vacancy type defects and their evolution under doping. The results of the PALS experiment indicate that doping KCl by Zn2+ ions, at first increases the concentration of mono vacancies and in the second stage leads the creation of divacancy sites. Coincidence Doppler Broadening Spectroscopy (CDBS) is carried out to obtain the chemical environment of positron annihilation sites. The results of CDBS show that cation vacancies have a significant role in the annihilation process. An interesting observation is the participation of Zn2+ cations in the positron annihilation process which confirms that positrons are not completely localized on the anion sites. The internal consistency between the results of PALS and CDBS experiments is also clarified.

Deposition of Ti6Al4V Thin Films by DC Magnetron Sputtering: Effect of the Current on Structural, Corrosion and Mechanical Properties

Ti6Al4V films have been prepared by DC magnetron sputtering technique at different currents (600, 700, 800 and 900 mA); target–substrate distance has been 3 cm. The depositions were carried out from Ti6Al4V alloy target. The deposition rate increases with increasing the current. The current effect on the crystalline quality and texture has been investigated by means of X-ray diffraction. β-Phase has been identified, and the grain size has been found to increase with increasing the current. The composition of the films has been determined by proton-induced X-ray emission and Rutherford backscattering technique. The Ti ratio was found to increase with current. The results obtained indicate that the TiAlV films by DC magnetron sputtering can inhibit the aggressive action of corrosion media. With increasing the current to improve film quality (bigger grain size), film Ti6Al4V/SS304 improved corrosion resistance for 304 substrate; microhardness was measured using Vickers method by applying 10 g load. Ti6Al4V film improves corrosion resistance and microhardness.

Geochemistry of Au-bearing pyrite from the Sepon Mineral District, Laos DPR, Southeast Asia: Implications for ore genesis

The Sepon gold-copper district occurs along the Truong Son Foldbelt in a 10 km × 40 km east-trending corridor in southern Laos. This study has investigated the nature of gold in pyrite and ore-forming fluid characteristics using Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) and Proton Induced X-ray Emission (PIXE) techniques. Gold is present as invisible gold (Au+1) and as nanoparticles of gold (Au0) in both sedimentary-rock hosted gold and skarn Cu-Au deposits. Gold is present in an early syngenetic pyrite generation (pyrite 2B) with concentrations to 0.5 ppm. Post-sedimentation processes included formation of quartz veins which host pyrite 3B with concentrations to 1.8 ppm Au. The highest concentrations of gold were found in the rims of hydrothermal vein-hosted pyrite 4A and in skarn related pyrite, suggesting gold concentration at a later stage during the ore-forming processes and not during sedimentation.As rhyodacite-porphyry is proximal to calcareous shale and dolomite that host ores, it is plausible that the emplacement of rhyodacite-porphyry introduced significant amount of hydrothermal fluids that circulated through fractures and favoured high grade (to 293 ppm Au) in pyrite 4A and pyrite SKN2. Gold is preferentially concentrated in As-rich zones and in areas that underwent brittle deformation, as evidenced by fracture-fill coarse-grained pyrite 4A, indicating a structural control to ore formation. The predominance of Se, Bi and Te in pyrite SKN1 and the elevated concentrations of Bi, Cu, Se, Sn and Mo in pyrite SKN2 raise the possibility of derivation from a magmatic source. The presence of primary hematite associated with the skarn suggests prevailing oxidising fluid conditions during Au mineralisation in pyrite SKN2.There is a striking chemical similarity between pyrite 4A core and py-SKN1 and rimmed zones of pyrite 4A and pyrite SKN2, which indicates possibility of two types of hydrothermal fluids. The As-rich fluids with elevated concentrations of Au, Se, Sb, Tl, and Cu recorded in pyrite 4A rims and pyrite SKN2. The As-poor fluids with elevated concentrations of Ni and Pb yielded in pyrite 4A cores and pyrite SKN1. The chemistry of pyrite has also shown that both ore-forming fluids are undersaturated in Au similar to Au-bearing pyrite in the Carlin-type deposits, Nevada, USA.

Proton-induced X-ray emission (PIXE) analysis of trace elements of total atmospheric deposit (TAD) around a smelting industry: Aerial pollution monitor

ABSTRACTThis study monitored total atmospheric deposit (TAD) around a smelting plant in Ile-Ife, Nigeria to assess the contributions of the industry to Nigeria's air-shed pollution. Samples were collected for 12 consecutive months using an Australian model gauge, harvested after 30 d of exposure, filtered and dried to constant weights using oven. Monthly deposition rates were determined and elemental characterizations of the TAD samples were done using proton-induced X-ray emission technique. Results revealed that the monthly deposition rates ranged from 0.69 to 4.62 gm−3 and was more pronounced in Harmattan. Twenty-three elements were detected; their total elemental concentrations ranged from 1.23 to 13.63 mg m−3 with Fe having the highest concentrations, while Na has the least. Pearson correlation indicated that some elements have common sources and/or similar chemical properties; enrichment factor showed that Fe, Zn, Pb, Mn were extremely enriched in the study area, modified degree of contamination (3.75) and pollution load intensity (1.21) showed that the neighborhoods could be exposed to high air pollution related impacts. Positive matrix factorization model revealed three distinct sources: Smelting emission (63%), biomass burning (17%), and suspended input material emissions (21%). The study concluded that the smelting activities posed a great hazard to receptors around the smelting industry.

Assessment of artisan's exposure to heavy metals from tantalite ore mining sites in Oke-Ogun, Oyo State, Nigeria

Mining activities cause disequilibrium in the bound states of heavy metals in rocks, soils and mineral ore. These heavy and toxic metals find their ways into the food chain thereby posing health risks along the chain. Furthermore, the work scenarios in mining activities have exposure pathways such as inadvertent ingestion and inhalation of dust and materials from the sites . The dose levels due to heavy metals in tantalite samples from Oke-Ogun, Oyo State have been estimated. Twelve samples of tantalite ore [(Fe, Mn) Ta2O6], were obtained from the mining sites. 500mg of the pulverized samples were pelletized for their elemental analysis using proton Induced X-ray Emission technique. Hazard indices due to exposure to carcinogenic elements in Tantalite were estimated based on United State Environmental Protection Agency (USEPA) dose model. Chromium, Lead and Arsenic are the only carcinogenic elements found in the samples and average concentrations 311.05, 2533.26 and 127.35 ppm respectively and are higher than permissible limit recommended by Abundance elements in average crustal rock (AEACR) (100, 10.1 and 2-0 ppm respectively). The summation of hazard indices values estimated for carcinogenic elements are greater than unity. The estimated Life time average daily dose for the carcinogenic elements is 6.86E-06 mg/kg. The cancer risk estimated for the carcinogenic elements in Komu and Eluku is of the order Cr (1.32E-05) > Pb (5.83E-08). The total risk for these elements is 1.32E-05 and this value is within the permissible limit range of 10-4 - 10-6 recommended by USEPA, 1998.

Heavy Metal Contamination in Agricultural Soil at DEPZA, Bangladesh

Higher accumulation of toxic heavy metals in rice grown in agricultural soil may lead to health disorder. The present study was carried out to assess the levels of different heavy metals like potassium, calcium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper and zinc in agricultural soil. The soil samples were collected by soil auger from the arable fields of Nolam near Dhaka Export Processing Zone Area (DEPZA), Savar, Dhaka of Bangladesh. The samples were irradiated using 3MV Van de Graaff Accelerator at the Atomic Energy Centre, Dhaka and Proton Induced X-ray Emission (PIXE) technique was employed for the analysis. The results indicated a substantial build-up of heavy metals in surface soil andsub-surface soil. Average metal concentrations were calculated and compared with reference values. The persistence of heavy metals in surface soil was higher than the sub-surface soil and it exceeded the standard safe limit. Uptake and translocation factor of heavy metal from surface soil to sub-surface soil were quite distinguished for almost all elements examined. In terms of health risk, the observed highest concentrations of these elements in soil could have an effect on human health which may pose public health hazards and for this pretreatment process of waste water is necessary for reducing the amount of heavy metals before using it to the agricultural soil. Wastewater from industries or other sources carries an appreciable amount of toxic heavy metals therefore their discharge into the environment must be minimized and carefully controlled.

Elemental Analysis of Commonly Consumed Rice in Nigeria using PIXE Technique

This study investigated the essential element (P, Cl, K, Ca, Mn, Fe, Cu and Zn) concentra-tions of some local and imported rice commonly consumed in Nigeria. This is done in order to select the rice with high nutrient to combat malnutrition, especially in children. Proton-induced X-ray emission (PIXE) techniques available at iThemba Labs Someset West, South Africa was used for the analysis. The elemental concentration obtained for Ofada are \(8805.5\boldsymbol{\pm}221\), \(276.5\boldsymbol{\pm}32\), \(3704.5\boldsymbol{\pm}39\), \(212$\boldsymbol{\pm}8\), \(110.5\boldsymbol{\pm}8\), \(125.5\boldsymbol{\pm}7\), \(14.5\boldsymbol{\pm}1\) and \(44.5\boldsymbol{\pm}4\) ppm, while for the imported rice we got \(2862.5\boldsymbol{\pm}150\), \(399\boldsymbol{\pm}22\), \(1433\boldsymbol{\pm}28\), \(4.15\boldsymbol{\pm}2\), \(8.4\boldsymbol{\pm}0.8\), \(4.75\boldsymbol{\pm}1\) and \(9.5\boldsymbol{\pm}2\) ppm for P, Cl, K, Ca, Mn, Fe, Cu and Zn respectively. Phosporus (P) has the highest elemental concentration in all samples. Ofada, one of the local rice was found to have the highest elemental concentration while pure imported rice had the lowest concentrations of the elements. The study suggests that consumption of locally-cultivated (Ofada) rice should be encouraged in order to reduce malnutrition in children in Nigeria.

Micro–PIXE Investigation of Trace Elements Ca, Fe, and Zn in Cataractous Human Lenses

Trace elements concentrations of Ca, Fe, and Zn in cataractous human lenses have been determined using the proton induced X-ray emission technique (PIXE). The technique was selected due to its sensitivity and only modest requirements for sample material processing and preparation. In the study a statistically significant sample of post–surgery (phacoemulsification method) human lenses with cataract was analyzed, targeting two diseases, often accompanying the cataract: diabetes and glaucoma. Patients were split into three, not overlapping groups: control, diabetic and glaucoma. Elevated levels of Zinc (strong effect) and Iron (weak effect) were measured for fraction of diabetic patients treated with insulin or pills. Samples from fraction of patients with glaucoma showed very elevated Zinc levels, often reaching concentration values of several hundreds of ppm, about one order of magnitude higher than in remaining cases. Due to overwhelming popularity of the phacoemulsification procedure and the ease of sample preparation for PIXE, current study suggests new perspective in medical diagnostic.

Characterization of Size-Fractionated Particulate Matter and Deposition Fractions in Human Respiratory System in a Typical African City: Nairobi, Kenya

Information from elemental and mass composition of size-fractionated airborne particle matter (PM) provides insightful knowledge about their impact on human health, meteorology and climate. To attain insight into the nature of sizefractionated PM from a typical African city, samples were collected from an urban background site in Nairobi, Kenya, during the months of August and September in 2007. PM samples ranging in size from 0.06 to 16 µm aerodynamic diameter were collected on pre-weighed polycarbonate filters with 0.4 µm pore size using a nine-stage cascade impactor. Particles less than 0.06 µm were collected on a backup filter. A total of 170 samples were collected and analysed for trace elements using the Proton Induced X-Ray Emission (PIXE) technique. The analysis showed that Si, Fe and S dominated in all size ranges and displayed unimodal mass-size distribution whereas K, Cu, Zn and Pb, depicted bimodal mass-size distribution highlighting the multiplicity of their sources. To estimate human exposure to PM, deposition fractions of both the coarse and fine PM in the human respiratory system were calculated. The deposited concentration was found to be highest in the head airways region compared to the tracheobronchial and pulmonary regions.

Proton induced X-ray emission-based analysis of trace element composition of cotyledon derived in vitro callus culture of Abrus precatorius L.: a multimedicinal wild legume

Quantitative estimation of inorganic elements of cotyledon-derived callus tissues of a medicinal legume, Abrus precatorius L. was determined using Proton induced X-ray emission technique. Nine trace elements namely Cu, Cr, Co, Zn, Mn, Fe, Se, Br and Ti in addition to two macro-elements K and Ca were identified, quantified and compared with each culture passage to monitor the variation in trace element accumulation. Experimental findings revealed that, 10-week-old calli was more efficient than others in accumulating inorganic elements. These results through light on the implication of in vitro callus cultures as a viable, alternative and proliferating renewable resource of medicinally useful elements for designing of drugs and also helping in natural germplasm conservation.

Standardization of proton-induced x-ray emission technique for analysis of thick samples

This paper describes the standardization of the proton-induced x-ray emission (PIXE) technique for finding the elemental composition of thick samples. For the standardization, three different samples of standard reference materials (SRMs) were analyzed using this technique and the data were compared with the already known data of these certified SRMs. These samples were selected in order to cover the maximum range of elements in the periodic table. Each sample was irradiated for three different values of collected beam charges at three different times. A proton beam of 2.57 MeV obtained using 5UDH-II Pelletron accelerator was used for excitation of x-rays from the sample. The acquired experimental data were analyzed using the GUPIXWIN software. The results show that the SRM data and the data obtained using the PIXE technique are in good agreement.

Trace elements in particulate matter of ambient air at petroleum filling stations

Size segregated suspended particulate matter (PM2.5 and PM10-2.5) in air at four major petroleum-filling stations in Ile-Ife, Nigeria, were monitored using double staged “Gent” stacked samplers to assess variations in mass loads and elemental concentrations of 25 elements. Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br, Rb, Sr, Zr, Cs, Ta, W, and Pb were determined in both fractions by external ion beam proton-induced X-ray emission technique. Enrichment factors and pollution indices were calculated and results revealed that most elements were anthropogenic in both fractions with concentrations exceeding the World Health Organization guideline standards.

Lung distribution, quantification, co-localization and speciation of silver nanoparticles after lung exposure in mice

Large knowledge gaps still exist on the toxicological mechanisms of silver (Ag) engineered nanoparticles (ENPs); a comprehensive understanding of the sources, biodistribution, toxicity and transformation of Ag ENPs along their life cycle and after transfer in living organisms is needed. In a previous study, mice were pulmonary exposed to Ag ENPs and local (lung) and systemic toxic effects together with biodistribution to organs including heart, liver, spleen and kidney were investigated. Here, Ag lung distribution, local concentration, co-localization with other elements such as Fe, Cu and S, and speciation were determined after lung exposure to Ag ENPs using micro X-ray fluorescence (μXRF), micro X-ray absorption near edge structure spectroscopy (μXANES) and micro proton-induced X-ray emission (μPIXE) techniques. We found that approximately a quarter of all macrophages in the lumen of the airways contained ENPs. High local concentrations of Ag were also detected in the lung tissue, probably phagocytized by macrophages. The largest part of the ENPs was dissolved and complexed to thiol-containing molecules. Increased concentrations of Fe and Cu observed in the Ag-rich spots suggest that these molecules are metallothioneins (MTs). These results give more insights on the behavior of Ag ENPs in the lung in vivo and will help in the understanding of the toxicological mechanisms of Ag ENPs.