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1.
Successful reproduction requires a well developed genital tract, including a good cooperation between hypothalamus, pituitary, ovaries and uterus on the female side and good sperm quality and motility on the male side. Heavy metals may interact with every single step of these processes, and after successful implantation the feto‐placental unit may be another target for heavy metal toxicity. In this review the reproduction process and the interaction of the heavy trace elements Cd (cadmium), Pb (lead) and Hg (mercury) are described.  相似文献   

2.
Environmental Geochemistry and Health - The Alto da Várzea radium mine (AV) exploited ore and U-bearing minerals, such as autunite and torbernite. The mine was exploited underground from 1911...  相似文献   

3.
The shell composition of 5 species of barnacles [Balanus balanoides (L.), B. crenatus Bruguière, B. hameri Ascanius, Elminius modestus Darwin and Chthamalus stellatus (Poli)] collected from four different sites on the coast of North Wales and one site in the Irish Sea were studied using chemical, X-ray diffraction and electron-microprobe analyses. All the shells consisted of calcite. The trace substances studied were Mg, Sr, Na, Mn, PO4, and SO4. Other trace elements detected included Si, Li, Ba, Zn, Cl, and Al. For each species, Mn was the only element in the shell which varied significantly from one locality to another. Variation of concentration of Mn in the shells may be related to the variations of the concentration of Mn in the water, since concentrations in the shells were highest in (estuarine) waters containing high concentrations of Mn. In Balanus balanoides L. and Elminius modestus Darwin, the Mn:Ca and Mg:Ca ratios decreased with decreasing shore level and Sr:Ca varied in the opposite direction. When B. crenatus Bruguière, a subtidal and lower littoral species, and B. hameri Ascanius, a Continental-Shelf species, were compared with the intertidal, species B. balanoides and E. modestus, the Mn:Ca and Mg:Ca ratios followed the same decreasing trend, and the Sr:Ca ratios the same increasing trend with increasing depth. These variations may be related either to increased growth rate of the shells of each species or maxium temperature to which the species is exposed, or both. The differences between species are more consistently reflected, in the concentration of Mn. However, since the concentration, of Mn is correlated with the amount of organic matter in the shell, the specific variations may reflect only the variations in the amount of organic material in the shell of each species.  相似文献   

4.
Cu, Cr, Mn, Ni and Zn contents were quantified for three wild-growing edible species of macrofungi (Boletus edulis, Macrolepiota procera and Cantharellus cibarius) and underlying soil samples collected at forest sites in Lubuskie voivodeship, Poland. The total concentration of the analysed elements was determined using an ASA iCE 3000 series atomic absorption spectrometer. The analysis found significant differences in bioaccumulation between species and differing distributions of trace elements in the caps and stalks of fruiting bodies. Bioaccumulation factors revealed that Zn and Cu are the most bioaccumulated elements, whereas Cr and Mn are excluded from bioaccumulation. Macrolepiota procera showed the highest bioaccumulation of Cu, and Zn is accumulated to the greatest extent by Boletus edulis. A few significant differences (p≤0.05) between the examined species were observed.  相似文献   

5.
Principal component analysis of trace elements in industrial soils   总被引:4,自引:0,他引:4  
The concentrations of the elements Cr, Pb, Cd, Zn, Ni, Mn, Cu and As in soil samples from industrial areas in Serbia were studied. The complexity of the data of eight elements in fifty-nine soil samples was reduced by principal component analysis. Three significant factors, in which 78% of the total variance in the data was found, were attributed to possible pollution sources. The crude and fuel oil burning, local smelters and exhaust emissions were shown to impact heavily the soil trace element profile, whereas no distinct soil type factor was observed. This approach, evidencing spatial relationship, enabled a differentiation between the soil samples originating from different areas.Selected article from the Regional Symposium on Chemistry and Environment, Krusevac, Serbia, June 2003, organised by Dr. Branimir Jovancicevic  相似文献   

6.
Health risk of arsenic (As) has received increasing attention. Acute and chronic exposure to As could cause several detrimental effects on human health. As toxicity is closely related to its bioaccessibility and metabolism. In real environment, many factors, such as diet and nutrition, can influence As bioaccessibility, metabolism and toxicity. This paper mainly reviews the influences of diets and elements on As bioaccessibility, metabolism and toxicity and their underlying mechanisms to provide suggestions for future investigations. Vitamins, jaggery, fruit, tea, glutathione, N-acetylcysteine and zinc could reduce the As-induced toxicity by increasing antioxidative enzymes to antagonize oxidative stress caused by As and/or increasing As methylation. However, bean and betel nut could increase risk of skin lesions caused by As. Interestingly, high-fat diet, selenium and iron have incompatible effects on As bioaccessibility, metabolism and toxicity in different experimental conditions. Based on current literatures, the As methylation and As-induced oxidative damage might be two main ways that the diets and elements influence As toxicity. Combined application of in vitro human cell lines and gastrointestinal models might be useful tools to simultaneously characterize the changes in As bioaccessibility and toxicity in the future research.  相似文献   

7.
Sea water was collected at several stations in the Bay of Lim at a depth of one meter below the surface, and before analysis, was filtered with 0.45-μm Millipore filters. Shallow water sediments were collected at the same locations. Humic acids used in this work were separated from near-shore sediments taken from various saline waters of the Bay of Lim. The prepared humic acids were then analysed for their elementary composition and also for positions of their hydrolytic products to obtain more data on how and to which characteristic part, the trace elements were related. The hydrolysis of humic acids was done by chemical methods in order to obtain four main components: amino acids, sugars, phenols and condensed benzene core. Neutron activation analysis was used for trace element analysis in evaporated portions of filtered sea water, sediments, soil, living organisms, humic acids and their hydrolytic products. This work was undertaken to obtain more data on the organic matter present in sediments and in seagrass flats, and also to collect more data on trace elements that are associated with typical and representative samples for the Bay of Lim. Analyses of trace elements associated with either humic acids or their hydrolytic products were performed with the purpose of gaining evidence as to which part of humic acids metals are bound. Humic acids or their decomposition products play an important role in the distribution and availability of a number of essential or nonessential trace elements. Results of this work indicate that humic acids influence the process of redistribution of trace elements in the investigated local coastal area.  相似文献   

8.
The aim of the study was to assess the influence of exposure to strontium on human blood and serum concentrations of magnesium, copper, cobalt, and molybdenum. Inductively coupled plasma–mass spectrometry (ICP-MS) was used to analyze the elemental content of whole blood and blood serum of 97 healthy men including 70 workers in a thermal power plant and 27 control subjects from the rural area of Dragash (Kosovo), an environment without pollution. The results showed that chronic moderate exposure to strontium decreases the levels of copper in blood (BCu) and serum (SCu), of cobalt in blood (BCo) and serum (SCo), and of molybdenum in blood (BMo). All changes in blood and serum concentrations of these essential elements were significant but remained within the normal range. The results suggest that strontium may induce adverse health effects in humans.  相似文献   

9.
Surface soils (0–15 cm) were sampled at 10–20 km intervals along two transects in Venezuela. One (1162 km, 70 samples) ran west to east parallel with the Caribbean coastline, the other (920 km, 92 samples) ran south to north from the frontier with Brazil to the Caribbean shore. Sampling took place in both a wet and a dry season. Trace metals were extracted from dried, sieved (<2 mm) soil with boiling aqua regia followed by analysis by ICP or flame AAS. Metal values did not differ significantly between the two seasons and dates were averaged. Geometric mean values for the west–east transect were: Cr=41.5, Cu 17.9, Cs 3.6, Li=13.9, Mn=294, Ni=21.3, Pb=17.4, Sr=39.4, V=60.4 and Zn = 83.7g g–1, respectively. Similarly, for the south–north transect Cr=21.3, Cu=4.3, Cs=1.1, Li=2.0, Mn=55.7, Ni=4.4, Pb=6.1, Sr=13.3, V=28.2 and Zn=16.7g g–1, respectively. A classification of samples by lithology showed surface soil composition to be related to rock composition. Metal values were low in the soils in the south of the country, in the Guyana highlands (Gran Sabana). Low Zn contents were prevalent. Lead contents were affected by roadside fallout from vehicles using leaded petrol except that high Pb contents of soils in the Gran Sabana were of more complex origin.  相似文献   

10.
11.
Coal ash samples taken from an active, currently filled cassette as well as samples taken from passive cassettes of the power plant in Obrenovac (Yugoslavia) were subjected to sequential leaching, comprising of extraction with distilled water, 1 M KC1 and 0.1 M HC1. Concentrations of trace and major elements found in extracts revealed that lead and cadmium are not present in significant concentrations, while other elements show different behavior: practically all absorbed trace elements and most of the major elements are partially leached during transport, while later, on the dump, only a slow release of most of the examined ion‐exchangeable elements occurs.  相似文献   

12.
A large number of data (n=488) were acquired from 2003 to 2006 for five Italian harbours and three control areas to determine trace element (Al, As, Cd, Cu, Zn, Pb, Hg, Cr, and Ni) levels in sediments. Results were utilised to evaluate, on a multivariate statistical basis, pollution levels, significant relationships between observed levels and specific factors, and enrichment factors. Of the factors tested, main human use of harbour, was best able to determine segregations in the observed trace element fingerprints. Compared with the concentration limit approach, the evaluation of enrichment factors, even if affected by mathematical approximations, represented a useful tool for environmental studies, allowing evaluation of the presence of sediments enriched by human activities and reducing the occurrence of both false positives and false negatives due to natural differences in aluminosilicate levels.  相似文献   

13.
Concentrations of a wide range of trace elements: arsenic, cadmium, cobalt, chromium, hafnium, nickel, thorium, uranium, zinc and the rare earth elements, cerium, europium, samarium, terbium and ytterbium were determined by instrumental neutron activation analysis in the brown alga,Fucus vesiculosus from Eckwarder Hörne, North Sea and from Rügen, Baltic Sea. Another brown alga,Sargassum filipendula from Sri Lanka, Indian ocean (representing an unpolluted control station) was similarly investigated. Cobalt, chromium and nickel concentrations were highest inF. vesiculosus from the North Sea while zinc was highest in samples from the Baltic Sea, reflecting high levels of these elements in coastal waters of the North and the Baltic sea. Cadmium, cobalt, nickel and zinc levels were lowest inS. filipendula from Sri Lanka, probably demonstrating lower levels of those elements in coastal waters. Concentration levels of hafnium, thorium, uranium, and the rare earth elements were highest inS. filipendula. Two years later in 1994,S. filipendula along withUlva sp. (green alga) was resampled from the same sampling site, and in addition to the above elements, six other trace elements (Ag, Ba, Br, Rb, Se and Sr) were determined.Sargassium filipendula showed a particular affinity for Ag, As, Br and Sr. For the other elements, marginal concentration differences were observed betweenS. filipendula andUlva sp., probably reflecting the regional background levels. Substantially higher concentrations of Hf, Th, U, and the rare earths were found again in the 1994Sargassum andUlva samples, reflecting the effect of a substrate rich in rare earth elements. The brown algae used in this study may be used to monitor trace elements in coastal waters.  相似文献   

14.
Environmental Geochemistry and Health - The city of Manaus is the biggest industrial city of the north Brazilian region, and a haphazard urbanization process characterizes it. The continuous...  相似文献   

15.
A fast, high-throughput and accurate method was developed for determination of Al, As, Ba, Cd, Co, Cr, Cs, Cu, Fe, Mn, Ni, Pb, Se, U, Zn, Sb, Sn, I and Hg in urine and serum by inductively coupled plasma mass spectrometry. The samples were directly analyzed after 1/20 (v/v) dilution in 0.4% (v/v) HNO3 and 0.005% Triton X-100. Three calibration modes were tested: aqueous and matrix matching with urine and serum. The accuracy was tested using reference materials of serum, urine and spiking. Results showed that the use of matrix matching calibration reduced the interferences and improved the recoveries for Al, Co, Pb and I in urine. The matrix matching did not affect the results considerably for serum. When serum was spiked with As, Co, Cs, Pb, U, Hg, I, Ba, Al, Cr and Ni, only matrix matching presented good recoveries. Helium was used as a collision cell gas reducing effectively polyatomic interferences for Al, Mn, Cu, Ni, Cr, Zn, As and Fe. Selection of the best internal standard was carried out for each element. The use of diluted HNO3 improved the limit of detection. Finally, the method was applied successfully in samples of urine from workers occupationally exposed.  相似文献   

16.
三江平原泥炭地微量元素垂直分布特征   总被引:2,自引:0,他引:2  
采用冬季采样,现场分层的方法,系统地研究了三江平原河床-河漫滩型泥炭地和谷底洼地型泥炭地微量营养元素和有益元素的垂直分布特征。结果表明,微量营养元素Cu、Zn、Fe、Mn、B和有益元素Ni、Sr、Ti、V、Co均有在G层急剧积累的趋势,Fe、Mn、B、Zn、Ti、Sr质量分数在Ase层明显高于泥炭层,某些微量元素间具有显著的相关性。  相似文献   

17.
In this study, trace element concentrations were determined in urine samples of patients with kidney and liver conditions from the Obafemi Awolowo University Teaching Hospitals Complex, Ile-Ife Nigeria. Urine samples from 80 patients whose ages ranged from 15 to 79 were used for the trace metals analysis. Variation of the trace metals including lead (Pb), cadmium (Cd), mercury (Hg), zinc (Zn), copper (Cu), and manganese (Mn) in urine samples were correlated with respect to gender, age, professions, personal habits and patients’ conditions. The levels of Pb in the urine samples of both male and female patients were found to be generally higher than those of Cd, Hg, Zn, Cu, and Mn. Highest levels of Pb and Cd were found in patients who smoked and drank and those with various kidney and liver conditions. Most of the trace metals except Mn occurred at levels that are deleterious to human health as they are above the standard threshold values expected in normal human urine, and raised cause for concern.  相似文献   

18.
An assessment of air quality of Belgrade, Serbia, was performed by determining the trace element content in airborne daily PM10 and PM2.5 samples collected from a central urban area. The ambient concentrations of Zn were the highest in PM2.5 (1,998.0 ng m−3). Multivariate receptor modelling (principal component analysis and cluster analysis) has been applied to determine the contribution of different sources of specific metallic components in airborne particles. The obtained results showed that vehicle traffic and fossil fuel combustion in stationary objects were the main sources of trace metals in Belgrade urban aerosols.  相似文献   

19.
Soil, plant, and water, as well as trace elements they contain, can influence human health through the food chain. A survey was conducted on distributions of trace elements in soils, plants, and drinking water in Rugao County, Jiangsu Province, China, an agricultural area with a high level of centenarians and nonagenarians. The ratio of people over 90 years old per 100,000 inhabitants (90-rate) based on village (about 4,000 residents in 4 km2) was correlated with trace elements in soil, drinking water, and rice by means of correlation analysis and/or principal component analysis. Although the average 90-rate in the whole area was as high as 277, the rates were not uniform across the entire region. The 90-rate in the area of loamy and strongly-developed Anthrosols and Cambosols was about 330, significantly higher than the 255 in the areas of sandy and strongly-developed Cambosols and of clayey and weakly-developed Cambosols. The concentrations of available Se, B, Ni, and Mo in soils of the area with the high 90-rate were markedly greater than those in the area with the low 90-rate. This was demonstrated by highly positive correlations between the 90-rate and available Se (r = 0.33), B (r = 0.21), Ni (r = 0.17) and Mo (r = 0.17) at the p < 0.01 level and high loadings of available Se (0.851), B (0.535), Ni (0.594) and Mo (0.394) in the longevous factor. Similar relationships between the available elements in soils and elements in water and rice were found. These results suggest that: (1) the available forms of elements in soil were more crucial to elemental bio-availability in the ecosystem and human health than total elements in soil; and (2) the element association above might have affected the 90-rate positively and could be an important environmental geochemical factor influencing the longevity of humans.  相似文献   

20.
We applied statistical methods to the data of a 5-year sampling period to characterize the features of trace elements in airborne particulate matter at the South Adriatic Coast. The analysis of surface soil samples was also performed. The data were processed by cluster analysis, enrichment factor determination and receptor rose statistics. It is shown that the principal element association consists of Fe, Mn and Ti originating from surface material resuspension. Hg and Se were shown to originate from more complex natural and anthropogenic processes. A strong emission source of Cd and Se was identified in the SSE direction.Selected article from the Regional Symposium on Chemistry and Environment Krusevac, Serbia, June 2003, organized by Dr. Branimir Jovancicevic.  相似文献   

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