首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 25 毫秒
1.
The role of metals in urinary stone formation has already been studied in several publications. Moreover, urinary calculi can also be used for assessing exposure of humans to minor and trace elements in addition to other biological matrices, for example, blood, urine, or hair. However, using urinary calculi for biomonitoring of trace elements is limited by the association of elements with certain types of minerals. In this work, 614 samples of urinary calculi were subjected to mineralogical and elemental analysis. Inductively coupled plasma mass spectrometry and thermo-oxidation cold vapor atomic absorption spectrometry were used for the determination of major, minor, and trace elements. Infrared spectroscopy was used for mineralogical analysis, and additionally, it was also employed in the calculation of mineralogical composition, based on quantification of major elements and stoichiometry. Results demonstrate the applicability of such an approach in investigating associations of minor and trace elements with mineralogical constituents of stones, especially in low concentrations, where traditional methods of mineralogical analysis are not capable of quantifying mineral content reliably. The main result of this study is the confirmation of association of several elements with struvite (K, Rb) and with calcium phosphate minerals, here calculated as hydroxylapatite (Na, Zn, Sr, Ba, Pb). Phosphates were proved as the most important metal-bearing minerals in urinary calculi. Moreover, a significantly different content was also observed for Fe, Zr, Mo, Cu, Cd, Se, Sn, and Hg in investigated groups of minerals. Examination of such associations is essential, and critical analysis of mineral constituents should precede any comparison of element content among various groups of samples.  相似文献   

2.

In order to understand the processes of stone formation, compositional, spectroscopic, mineralogical and crystallographic characteristics of human urinary stones collected from patients in Sri Lanka were investigated in detail. The data showed that the majority of urinary calculi were calcium oxalate, either whewellite or weddellite. Other solid phases of stones were composed of struvite, uricite and hydroxylapatite. However, mixed compositions were common except for whewellite stones which occur frequently in pure form. Scanning electron microscope observations and associated energy-dispersive X-ray analyses revealed that whewellite or weddellite was well crystalized compared to other stones types, while phosphate stones were mostly cryptocrystalline. The average δ13C and δ18O of stones were − 32.2‰ (− 37.3 to − 17.4‰) and − 24.2‰ (− 26.7‰ to − 8.9‰), respectively. The δ13C values were highly depleted compared to North American and European urinary stones. This may be due to food habits of Asians who consume rice as the staple food.

  相似文献   

3.

This paper represents the first result of an active collaboration between the University of Sannio and the San Pio Hospital (Benevento, Italy), started in the 2018, that aims to a detailed mineralogical investigation of urinary stones of patients from Campania region. Herein, selected human bladder stones have been deeply characterized for clinical purposes and environmental biomonitoring, focusing on the importance to evaluate the concentration and distribution of undesired trace elements by means of microscopic techniques in the place of conventional wet chemical analyses. A rare bladder stone with a sea-urchin appearance, known as jackstone calculus, were also investigated (along with bladder stones made of uric acid and brushite) by means a comprehensive analytical approach, including Synchrotron X-ray Diffraction and Simultaneous Thermal Analyses. Main clinical assumptions were inferred according to the morpho-constitutional classification of bladder stones and information about patient’s medical history and lifestyle. In most of the analyzed uroliths, undesired trace elements such as copper, cadmium, lead, chromium, mercury and arsenic have been detected and generally attributable to environmental pollution or contaminated food. Simultaneous occurrence of selenium and mercury should denote a methylmercury detoxification process, probably leading to the formation of a very rare HgSe compound known as tiemannite.

  相似文献   

4.
Kidney stones (urinary calculi) have become a global scourge since it has been recognized as one of the most painful medical problems. Primary causative factors for the formation of these stones are not clearly understood, though they are suspected to have a direct relationship to the composition of urine, which is mainly governed by diet and drinking water. Sixty nine urinary calculi samples which were collected from stone removal surgeries were analyzed chemically for their Na, K, Ca, Mg, Cu, Zn, Pb, Fe and phosphate contents. Structural and mineralogical properties of stones were studied by XRD and FT-IR methods. The mean contents of trace elements were 1348 mg kg−1 (Na); 294 mg kg−1 (K); 32% (Ca); 1426 mg kg−1 (Mg); 8.39 mg kg−1 (Mn); 258 mg kg−1 (Fe); 67 mg kg−1 (Cu); 675 mg kg−1 (Zn); 69 mg kg−1 (Pb); and 1.93% (PO43−). The major crystalline constituent in the calculi of Sri Lanka is calcium oxalate monohydrate. Principal component analysis was used to identify the multi element relationships in kidney stones. Three components were extracted and the first component represents positively correlated Na-K-Mg-PO43− whereas the␣second components represent the larger positively weighted Fe–Cu–Pb. Ca–Zn correlated positively in the third component in which Mn–Cu correlated negatively. This study indicates that during the crystallization of human urinary stones, Ca shows more affinity towards oxalates whereas other alkali and alkaline earths precipitate with phosphates.Contribution from the Environmental Geology Research Group (EGRG), Department of Geology, University of Peradeniya, Sri Lanka.  相似文献   

5.
Due to the increase in the number of urinary calculi disease cases in Jordan, stone samples were collected from patients from various Jordanian hospitals (Princes Basma (PBH), King Abdullah University (KAUH), Al-Basheer (ABH) and Al-Mafraq (AMH)). This study concentrates on the effect of trace metals in patients of urinary calculi. Trace metals were detected in 110 urinary calculi samples using X-ray fluorescence (XRF) and atomic absorption spectroscopy (AAS) techniques. Of the calculi examined, 21 were pure calcium oxalate (CaOax), 29 were mixed calcium oxalate/uric acid, 23 were mixed calcium oxalate/phosphate (apatite), 25 were phosphate calculi (apatite/struvite), five were mixed calcium oxalate monohydrate/struvite, four were urate calculi (mixed ammonium acid urate/sodium acid urate) and three were pure cystine calculi. The concentration measurement of Ca and other trace metals levels has been found useful in understanding the mechanism of stone formation and in evaluating pathological factors. It has been found that Ca is the main constituent of the urinary calculi, especially those stones composed of calcium oxalate and calcium phosphate. The concentration of most of the trace metals that were analyzed was (Ca = 48.18, Na = 1.56, K = 0.9, Mg = 3.08, Fe = 1.17, Al = 0.49, Zn = 0.7, Cu = 0.19, Mn = 0.029, P = 10.35, S = 1.88, Sr = 0.306, Mo = 0.2, Cr = 0.146, Co = 0.05, Ni = 0.014)%. In conclusion, metals concentration in Jordanian patient’s urinary calculi samples was higher than its equivalents of other patients’. It has been noted that there is no concentration of toxic trace elements (like Li, V, Pb, Cd, and As). Some heavy metals, however, were detected Mo, Cr, Co and Ni as traces. P and S ions are present in few calculi stones as traces.  相似文献   

6.
Urinary stone diseases are increasing in the Middle East. The majority of urinary stone cases are found in the northern part of the country. Stone samples taken from patients living in the Irbid area were collected from Princess Basma Hospital. The present study concentrates on the mineralogical and chemical composition of the urinary stones and on the effective environmental factors that assist in developing the different types of urinary stones. Using X-ray diffraction techniques, the mineralogical composition of the urinary stones was found to be as follows: oxalate, cholesten, and uric acid, with cystine stones occuring more frequently than the others. Cholesten and calcium oxalate stones are the most dominant types of stones. Calcium oxalate is the most common type of oxalate stone. Calcium oxalate is represented in: whewellite, wheddellite, and calcium carbonate oxalate hydrate minerals, in addition to other minerals such as brushite, ammonium phosphate, vaterite, valleriite, and bobierrite from other types of stones. Bobierrite (phosphate group) is a new mineral reported in urinary stones, and this has not been determined in any previous study worldwide. Apatite (calcium phosphate) is deduced using scanning electron microscope (SEM) images. The SEM technique determined crystal forms and systems, shapes, morphological features, and the names of the minerals forming urine stones, while optical properties are studied by polarizing microscope. X-ray fluorescence technique determined the concentrations of major and some trace elements. It revealed that Ca is the main constituent of the urinary stones, especially those composed of calcium oxalate and calcium phosphate. The concentration of trace elements was Ba = 1.57, P = 3.61, Fe = 1.78, S = 2.08, Zr = 4.63, Mo = 3.92, Cu = 1.89, Co = 1.56, and F = 4.2% and was higher in the urinary stones of Jordanian patients than in foreigners in the country. Questionnaires completed by patients suggest that the most significant factors directly effecting the formation of stones are water, climate conditions, food rich in protein and rich in different chemicals. Moreover, some drugs and diseases might also help in developing other stones.  相似文献   

7.

There is no information yet about plant species capable of accumulating many different metals/metalloids. The plants feasible for phytoremediation aims must grow fast, have high biomass, deep roots, and should accumulate and tolerate a range of toxicants in their aerial parts. In our research, greenhouse and field experiments have been performed to investigate accumulation and tolerance of not well-studied trace elements such as Br, Eu, Sc, Th (and also U) in couch grass and wheat. We compared bioaccumulation abilities of the plants with those of some other plant species grown under the same conditions. Additionally, we tested the effects of inoculation of seeds with Cellulomonas bacteria on phytoextraction of the trace elements from contaminated soils. For determination of elements, we used neutron activation analysis and ICP-MS. It was found that couch grass and wheat can grow in heavily contaminated soils and accumulate different toxic trace elements to levels that exceed physiological requirements typical for most plant species. Infection of seeds with bacteria resulted in a significant increase in the uptake of various trace elements and their translocation to upper plant parts. The use of couch grass and/or wheat, either alone or in combination with microorganisms, is a promising way to phytoextract metals/metalloids from contaminated soils.

  相似文献   

8.

Environmental geochemistry classifies elements into essential, non-essential and toxic elements in relationship to human health. To assess the environmental impact of mining at Datoko-Shega area, the distributions and concentrations of trace elements in stream sediments and soil samples were carried out. X-ray fluorescence analytical technique was used to measure the major and trace element concentrations in sediments and modified fire assay absorption spectrometry in soils. The results showed general depletion of major elements except titanium oxide (TiO2) compared to the average crustal concentrations. The retention of TiO2 at the near surface environment probably was due to the intense tropical weathering accompanied by the removal of fine sediments and soil fractions during the harmattan season by the dry north-east trade winds and sheet wash deposits formed after flash floods. The results also showed extreme contamination of selenium (Se), cadmium (Cd) and mercury (Hg), plus strong contaminations of arsenic (As) and chromium (Cr) in addition to moderate contamination of lead (Pb) in the trace element samples relative to crustal averages in the upper continental crust. However Hg, Pb and Cd concentrations tend to be high around the artisanal workings. It was recognised from the analysis of the results that the artisanal mining activity harnessed and introduces some potentially toxic elements such as Hg, Cd and Pb mostly in the artisan mine sites. But the interpretation of the trace element data thus invalidates the elevation of As concentrations to be from the mine operations. It consequently noticed As values in the mine-impacted areas to be similar or sometimes lower than As values in areas outside the mine sites from the stream sediment results.

  相似文献   

9.
This paper presents measurements of major, minor, metal trace elements and radionuclides in sediments and in Posidonia oceanica samples from north-western Sicily (Italy). The mineralogical and chemical composition of sediments were determined by X-ray diffraction and X-ray fluorescence techniques, respectively. A flame atomic absorption spectrophotometry was used to measure concentrations of Cu, Zn, Cd and Pb in P. oceanica samples and in sediments. Specific activities of selected radionuclides have been determined by high-resolution gamma spectrometry. Standard statistical analysis was used to assess correlations between different elements and different sample types.  相似文献   

10.
We review the evolution, state of the art and future lines of research on the sources, transport pathways, and sinks of particulate trace elements in urban terrestrial environments to include the atmosphere, soils, and street and indoor dusts. Such studies reveal reductions in the emissions of some elements of historical concern such as Pb, with interest consequently focusing on other toxic trace elements such as As, Cd, Hg, Zn, and Cu. While establishment of levels of these elements is important in assessing the potential impacts of human society on the urban environment, it is also necessary to apply this knowledge in conjunction with information on the toxicity of those trace elements and the degree of exposure of human receptors to an assessment of whether such contamination represents a real risk to the city’s inhabitants and therefore how this risk can be addressed.  相似文献   

11.
Trace elements such as cadmium (Cd) may be inadvertently added to cropland soils through application of fertilizers, irrigation water, and other amendments. These toxic trace elements pose a potentially threat to soil quality and, through the food chain transfer, to human health. A generalized soil trace element mass balance model that accounts for the interactive processes governing the reactions of trace elements in soils, and consequently removed with crop harvest and leaching out of the soil profile with irrigation water was developed in this research. The model conceptually approximates the mechanisms and kinetics of a real field cropland system. The model was used to evaluate the long-term cultivation on distribution of Cd in California croplands. Under typical California cropping practices, Cd added into the soils accumulated primarily in the plow layer while the Cd content below the plow layer was barely affected. After 100 years of continuous cultivation, the soil Cd content of the plow layer increases from the background level 0.22 mg kg−1 to 0.40 mg kg−1. The accumulation of Cd in the plow layer is in proportion to the external inputs and is affected by the soil and plant characteristics, and management practices. The model can be used to evaluate the environmental fates of other toxic element in soils with case specific parameters.  相似文献   

12.
The present work was designed as an extension of a previous study of a barium anomaly observed in stream sediments of the Kupa River. In its upper part the Kupa River drains a region underlain by a trans-boundary aquifer. The river is a significant water resource in a region of tourism, sport, and fishing in both Croatia and Slovenia. The contamination source is situated in Homer (Lokve), Croatia, where barite was mined until 10 years ago. The barium processing waste material (<3-mm fraction) was carelessly deposited in gardens, forests, and into a sinkhole, which has an underground link with the Kupica River, a tributary of the Kupa River. Barium waste and stream sediments were analyzed using comparative techniques: X-ray diffraction (XRD), X-ray fluorescence (XRF), Mössbauer spectroscopy, and grain size analysis. XRD of the waste material identified the major minerals quartz, barite, and dolomite and the Fe-containing minor minerals muscovite and goethite. Barite was identified as a minor or trace mineral in the Kupica River sediments. XRF analysis of the waste material has shown Ba and Fe to be the predominant elements, Ca and K to be minor elements, and Mn, Zn, Sr, Pb, Co, Cu, As, Zr, Rb, Y, and Mo to be trace elements. Mössbauer spectroscopy performed at room temperature (RT) was used to study iron minerals, particularly to obtain information on the valence status of Fe ions. Grain size analysis of the waste material (<63-μm fraction) has shown that it contains 23.5% clay-size material in comparison with 7–8% clay-size material in stream sediments. It is our aim to combine geochemical and medical methods to investigate the possible impact of waste disposal on human health in Lokve. At this stage of the work, concentrations of Ba and other toxic elements in the water compartment of the Kupica River (a source of drinking water) have not been monitored by Croatian Waters (name of the Croatian water authorities). The necessity of such measurements in future studies has been highlighted. A preliminary study of diseases diagnosed in Lokve shows that about 18% of the total inhabitants have serious medical problems. Diseases of the circulatory system, endocrine, nutritional, and metabolic diseases, neoplasms, and respiratory diseases predominate. This paper calls for further multidisciplinary research on the health effects of barium and trace elements, as well as for bioremediation of contaminated gardens and for watershed management of vulnerable karstic aquifers.  相似文献   

13.
This paper presents measurements of major, minor, metal trace elements and radionuclides in sediments and in Posidonia oceanica samples from north-western Sicily (Italy). The mineralogical and chemical composition of sediments were determined by X-ray diffraction and X-ray fluorescence techniques, respectively. A flame atomic absorption spectrophotometry was used to measure concentrations of Cu, Zn, Cd and Pb in P. oceanica samples and in sediments. Specific activities of selected radionuclides have been determined by high-resolution gamma spectrometry. Standard statistical analysis was used to assess correlations between different elements and different sample types.  相似文献   

14.
Diet is the major route of exposure to contaminants, therefore food monitoring programs are essential to estimate the degree of human risk. We present a study undertaken in Austria dealing with the total uptake of mercury, cadmium, arsenic and lead. The dates were calculated from diet as well as from commercial food. Higher contaminated foodstuffs are registered and a comparison was made between body burden of babies and adults on the basis of bodyweight. It was pointed out, that cooked or washed food ready to eat has a lower burden of lead and cadmium than non prepared food due to household processing, which may decontaminate food to some extent’ Arsenic content was not reduced, because it is bound chemically and not primarily deposited on the surface of food such as in the case of lead. It was mentioned that the type of compound plays an important role in the assessment of action of those elements on humans.

Their biological activity is not necessarily related to their concentration in food. As in the case of selenium and chromium one has to take into consideration that there is a narrow range between benefit and harm, toxicity, and minor supply.

Therefore we conclude, that due to interactions of elements, their different biological activity and due to the difference of compounds present in food, we have to relativate the terms toxicity and essentiality. Then we can get a more profound insight into the problems of trace elements in food.  相似文献   

15.
Inorganic pollution comprises both major and minor constituents, although only 12 chemical elements may be considered major components. Twenty‐eight elements constitute a group of common minor elements and an additional 13 elements comprise a group of less common minor constituents. Reliable quantitative data are required on the occurrence of these substances in a wide variety of water types, usually at extremely low concentrations. The analysis of standard reference water samples provides information on the overall reliability of water‐quality data. Although most major constituents may be determined with acceptable reliability, determinations of certain minor constituents lack comparable precision; for example, determinations of boron, nickel, and chromium. Few precision data are available on the determination of the less common trace elements. Several comparatively new analytical techniques, such as flameless atomic absorption spectrophotometry, voltammetry, and emission spectroscopy with plasma excitation, appear capable of providing improved sensitivity.  相似文献   

16.
The current paper involves overview of several studies concerning quantitative major and trace element analysis of different food samples, such as products of plant origin, e.g., locally grown vegetables (carrots, onions, potatoes) and products of animal origin derived with or without processing (cottage cheese, eggs, honey). Food samples were collected over the territory of Latvia in the time period 2009–2012. Sample pre-treatment was chosen according to the product specifics but mostly wet mineralization with concentrated nitric acid was applied. Analysis of major elements (e.g., Ca, Fe, K, Mg, Na) and trace elements (e.g., As, Cd, Co, Cr, Cu, Ni, Pb, Se, Zn) was performed by appropriate quantitative analytical technique: atomic absorption spectrometry, inductively coupled plasma mass spectrometry or total reflection X-ray fluorescence spectrometry. Not only the influence of environmental factors (e.g., geographical or seasonal impact) was detected in element dissemination in food, also botanical origin (if applicable) and applied agricultural praxis, product processing and storage specifics were found to be important. Possible food contamination by potentially toxic elements can be associated mostly with the consequences of anthropogenic activities. The studies revealed the significance of food research in the context of environmental science.  相似文献   

17.
An enterolith surgically removed from a Grant's zebra was investigated by standard mineralogical techniques including X-ray diffraction, scanning electron microscopy and electron microprobe analysis. It was predominantly composed of a suite of phosphate minerals which have precipitated on and between aggregates of undigested plant material. It was apparently cored by a small nidus of granitic rock which served as a site for heterogeneous nucleation for the larger phosphatic overgrowth. Phosphate was deposited by at least two distinct mechanisms. In the enterolith's core, phosphate minerals replaced or rimmed silicate grains (e.g. feldspars and quartz) which are relics of the disaggregated granitic nidus. As the enterolith subsequently accreted outwards from the nidus, struvite was precipitated directly onto fibres of plant material, or within the pore spaces between them. The generally fine grain size of struvite in enteroliths, relative to that in urinary calculi, may be due to the ubiquitous presence of the undigested plant fibres. Struvite, close to (NH3)0.9K0.1MgPO4 · 6H2O in composition, is the only phosphate mineral in the outer portions of the enterolith. Within the enterolith's interior, struvite occurs subequally with Mg-vivianite, close to Mg2.9Fe0.1(PO4)2 · 8H2O in composition. Textural relations suggest that the mineralogical transformation of struvite to Mg-vivianite is a consequence of diagenesis, presumably related to a decrease in pH and/or (NH4)+ activity, within the core of the enterolith. If enterolith growth is mediated by the accumulation of a particular form of undigested plant fibre (e.g. lucerne hay), the identification and dietary removal of this material may prevent or at least impede the development of enteroliths.  相似文献   

18.

The combined exposure to aluminum (Al) and cadmium (Cd) causes more pronounced adverse health effects on humans. The kidneys are the main organs affected by internal exposure to Cd and Al via food and non-food items. The objective of present study was to measure the Al and Cd concentrations in cigarettes tobacco (branded and non-branded) and drinking water (domestic treated, ground and lake water) samples in southern part of Pakistan, to assess the risk due to ingestion of water and inhalation of cigarettes smoke containing high concentrations of both elements. The study population (kidney disorder and healthy) divided into two group based on consuming lake and ground water, while smoking non-branded cigarette as exposed, while drinking domestic treated water and smoking branded cigarette as non-exposed. Electrothermal atomic absorption spectrometry was used to determined Cd and Al concentrations in tobacco, drinking water and blood samples. The resulted data indicated that the levels of Al and Cd in lake and underground water were higher than the permissible limit in drinking water recommended by the World Health Organization. The biochemical parameters of exposed and referent patients, especially urinary N-acetyl-h-glucosaminidase, were used as a biomarkers of kidney disorder. Exposed kidney disorder patients have higher levels of Cd and Al than the exposed referents subjects, while difference was significant when compared to resulted data of non-exposed patients and referents (p = 0.01–0.001). The pearson correlation showed positive correlation between both toxic element concentrations in water, cigarettes versus blood samples of exposed subjects (r = 0.20–0.67 and 0.71–0.82), while lower values were observed for non-exposed subjects (r = 0.123–0.423 and 0.331–0.425), respectively.

  相似文献   

19.
Knowledge of the composition of human urinary calculi within a geographical area can lead to an understanding of the epidemiology of renal stone disease. Studies in the Durban area, with its high incidence of kidney and bladder stones, indicate that calcium oxalate is the overwhelmingly dominant (circa 80%) component, followed by uric acid. An important feature is the low occurrence of phosphate stones, especially those containing struvite.  相似文献   

20.
Nowadays, much attention is devoted to the study of toxic elements at trace and sub-trace levels in the investigation of particulate matter composition, especially in PM10 and PM2.5. Furthermore, it should be considered that the behavior knowledge is an other important task for understanding such species. Finally, the determination of particular elements with a few data in literature can assume relevant importance in industrial processes (Pd, Rh, Ir, etc. for catalytic pot, Sm, Ce, Eu, etc. for optical fibers and electronic process). In this article, we apply a nuclear technique, i.e. Instrumental Neutron Activation Analysis, for the study of metal composition in fine and coarse fractions. This nuclear technique allows the determination of about 25 elements: for some of them, this is the first determination in the ambient air of Rome. The investigation was performed in a reserved area in downtown Rome during a 15-day intensive campaign. The sampled filters were irradiated at the nuclear reactor Triga Mark II (ENEA-Casaccia Laboratories) at neutron flux of 2.6?×?1012?n?cm?2?s?1 for 32.55?h. The measurements of the γ-ray allow the qualitative and quantitative analysis. The element levels in fine and coarse fractions will be shown with the correlations among some elements being more interesting in the toxicological field: basically, the concentrations are very low.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号