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1.
In Finland, a new Government Decree on the Assessment of Soil Contamination and Remediation Needs (214/2007) came into force on 1 June 2007. According to the Decree, natural baseline concentration levels should be taken into account when assessing potential soil contamination and the need for remediation. This applies particularly in the case of toxic metallic elements, since baseline concentrations may naturally be rather high. The new decree prescribes soil screening values for 52 substances or groups of substances. The natural baseline concentrations have been taken into account in the definition of the screening values for inorganic pollutants. The Geological Survey of Finland (GTK) carried out a nation-wide geochemical mapping of till on a reconnaissance scale in 1983 and on a regional scale during 1984–1992. These surveys have provided information on natural elemental distribution in subsoils of the glacial till. However, some important trace elements in regional mapping such as arsenic are missing from the analysis, and subsoil samples do not reflect the diffuse anthropogenic input. Thus, GTK has continued the survey work by determining geochemical baselines around suburban areas. Samples have been taken from humus, topsoil and subsoil layers, and the soil parent material has covered sandy soils, glacial tills and fine-grained sediments. According to the studies, a regional difference in the levels of arsenic and some other trace elements can be clearly seen, especially in minerogenic soils. The results illustrate the importance of information on regional baseline concentrations while assessing potential soil contamination.  相似文献   

2.
Particulate samples taken from both the indoor (working) and outdoor (community) environments contain a wide range of metallic trace elements most of which are mutagenic in at least one of the short term tests for genotoxicity currently in use. Because of the demonstrated presence of a short lived biologically active species (Cr(VI)), and the uncertainty with which the results of the screening of metallic compounds in short term tests can be interpreted in terms of human risk, great care must be taken to assure the appropriate collection, storage, and chemical and biological assay of such material. The sensitivity of the results for fly ash and welding fumes to variations in these protocols is demonstrated and discussed.  相似文献   

3.
We applied the solution-based inductively coupled plasma mass spectrometry to quantify trace elements in statoliths of Humboldt squid, Dosidicus gigas, collected from the high seas off Chile, Peru, and Costa Rica by Chinese squid jigging vessels during 2007–2009. All squid samples were aged and their spawning dates were back-calculated based on daily increments in statoliths. The most abundant trace elements in the whole statolith were Ca and Sr followed by other elements in the order of Fe, Mg, Zn, Ba, Cu, Mn, Ni, Al, Cr, Co, and U. Significant differences in Mn and Sr were found among samples from the three regions. Sr, Ni, Mn, and Co contributed significantly to the discrimination among the regions, with Co responsible for explaining most of the variation, followed by Ni, Mn, and Sr. Squid from the high seas off Costa Rica could be separated from those off Peru and Chile mostly due to the differences in Ni, Sr, and Co, while samples off Peru and Chile could be distinguished mainly because of differences in Mn and Co. Discriminant function analysis suggested that the overall cross-validated classification rate was 85.6 % with samples off Chile having the highest correct identification rates and samples off Costa Rica having the highest false classification rates. Significant positive relationships were found between sea surface temperature (SST) and Cr/Ca, Mn/Ca, and U/Ca, and there was a negative relationship between SST and Cu/Ca, Sr/Ca. This study suggests that the spatial difference in trace elements of statolith can be used to separate geographic populations of D. gigas and that elements having significant relationships with SST can be considered as natural indicators of ambient temperature.  相似文献   

4.
贵州省原煤中微量元素的组成特征   总被引:10,自引:0,他引:10  
倪建宇  冯新斌 《环境化学》1998,17(4):339-344
研究了贵州省各主要煤田中主要采煤层的As,B,Ba,Be,Cd,Co,Cr,C,Hg,Li,Ni,Pb,Sb,Se,Sr,Tl,V,Zn等微量元素的组成特征,贵州省原煤中微量元素的含量总体上的世界范围内的一致,但Sb,As,Hg等有害元素则明显富集,由于煤炭成因上的特殊性,其微量元素的组成除受煤植物的影响外,后期在煤作用对其有决定性的影响。  相似文献   

5.
Dissolved ions and suspended participates from twelve water samples from Sohag (different localities) and Aswan (behind and below the High Dam) areas were collected along the River Nile, upper Egypt, which is at present affected seriously by pressure of population, intense industrial and agricultural activities, and atmospheric fallout. Eighteen trace and nine major ions in solution and fourteen metals in suspension were analyzed to establish whether elements are of anthropogenic or natural origin. Results of this study show that the Nile water was contaminated with high concentrations of dissolved lead, and with copper, nickel and mercury to a lesser extent, suggesting that these contaminants are generated from anthropogenic activities. the other dissolved ions in the Nile are of natural origin because their metal concentrations fall within the range of the normal background and average world dissolved values for inland waters. Results show that the usual constituents of suspended particulates in the Nile seem to be some metals (Cu and Zn) adsorbed on iron and manganese oxide/hydroxide. the results also reveal that most trace and major metal particulates increase from south to north due to activities associated with the dense population living along the Nile banks. No significant differences were observed between the chemical composition of trace and major elements taken on the east and west river Nile banks.  相似文献   

6.
燃煤灰渣中微量元素分布规律的研究   总被引:23,自引:2,他引:23  
研究了锅炉飞灰和底灰中15种微量元素的含量和分布,探讨了煤炭燃烧后,微量元素在灰渣中的集散及其影响因素,飞灰和底灰中大多数元素高于全国土壤背景值,7种元素高于克拉克值,其余8种低于克拉克值,飞灰中多数元素的地球化学富集因子高于1,呈富集状态,而底灰中多数元素富集因子小于1,飞灰和底灰中微量元素含量与煤中微量元素含量呈线性关系,微量元素含量不仅与煤有关,还受锅炉燃烧方式等人为因素影响。  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.
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   

9.
在中国东部花岗岩、玄武岩和石灰岩地区布设91个采样点,采集土壤剖面和母岩样品,测试13种微量元素的含量,研究其纬向分异规律及影响因素。结果表时:(1)土壤微量元素含量顺序为:玄武岩土壤>石灰岩土壤>花岗岩土壤;(2)花岗岩和玄武岩上土壤微量元素含量与母岩接近,石灰岩上土壤微量元素含量远高于母岩;(3)花岗岩上土壤微量元素的含量由北向南呈降低趋势,而玄武岩和石灰岩上土壤微量元素含量由北向南均呈增高趋势,且与游离氧化铁含量的增高同步;(4)微量元素含量与氧化铁含量在玄武岩土壤中的相关性大于这两者在花岗岩土壤中的相关性。  相似文献   

10.
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   

11.
The current paper presents the concentration, distribution, and modes of occurrence of trace elements of 13 coals from south Brazil. The samples were collected in the state of Santa Catarina. Chemical analyses and the high ash yields indicate that all studied coals are rich in mineral matter, with SiO2 and Al2O3 dominating as determined by inductively coupled plasma-atomic emission spectrometry (ICP-AES). Quartz is the main mineral species and is associated with minor levels of feldspars, kaolinite, hematite, and iron-rich carbonates. The contents of trace elements, including As, Pb, Cd, Ni, Cr, Mn, Be, V, U, Zn, Li, Cu, Tl, and Ni, in coals were determined. A comparison of ranges and means of elemental concentrations in Santa Catarina, Brazil, and world coals shows that the ranges of most elements in Santa Catarina coal are very close to the usual worldwide concentration ranges in coal.  相似文献   

12.
The West Anatolian Region is one of the most important areas for industrialization, population density and traffic in Turkey. Therefore, the leaves of Populus nigra L. (Salicaceae), which are used as biomonitor to investigate the levels of the trace elements Cd, Pb, Fe, Zn and Cu, were sampled at 30 locations having different pollution levels in the region. The concentrations of elements were determined by atomic absorption spectrometry. The samples were collected at both reference and contaminated locations where iron was found as the priority element. The strong association between a gradient of contamination and concentration in all samples tested indicates that they are reflecting well the environmental changes, and that they appear as appropriate biological indicators of heavy metal contamination.  相似文献   

13.
Concentrations of trace elements in wheat grain sampled between 1967 and 2003 from the Swedish long-term soil fertility experiments were analyzed using ICP-MS. The long-term effect of inorganic and organic fertilization on trace metal concentrations was investigated including the impact of atmospheric deposition and myccorhiza, whereas other factors such as soil conditions, crop cultivar, etc. are not discussed in this paper. Mean values derived from 10 experimental sites were reported. Significantly declining Pb and Cd concentrations in wheat grain could be explained by lower atmospheric deposition. Mean Se contents in all samples were 0.031 mg kg−1 grain dry weight. No samples had sufficiently high Se concentrations for human (0.05 mg Se kg−1) or animal demand (0.1 mg Se kg−1). Concentrations of Co in wheat grain were extremely low, 0.002–0.005 mg Co kg−1 grain dry weight, and far below the minimum levels required by animals, which applied to all fertilizer treatments. A doubling of Mo concentrations in grain since 1975 resulted in Cu/Mo ratios often below one, which may cause molybdenosis in ruminants. The increase in Mo concentrations in crops correlated with the decline in sulfur deposition. Concentrations of Cu and Fe declined in NPK-fertilized wheat as compared to unfertilized or manure-treated wheat. Very low concentrations of Se and Co and low concentrations of Fe and Cu require attention to counteract risks for deficiencies. The main characteristic of the study is that there are few significant changes over time between different fertilizer treatments, but throughout there are low concentrations of most trace elements in all treatments. In general, good agreement between concentrations in wheat from the long-term fertility experiments and the national monitoring program indicate that values are representative.  相似文献   

14.
The Domingo Rubio tidal channel (Palos de la Frontera, Huelva, Spain) is an estuary located in the mouth of the Tinto River. The estuary is affected by different sources of pollution (waters of the Tinto River, contaminated with trace elements from the Iberian Pyrite belt, and effluent from the Huelva chemical industrial area). Soil and the most frequent plant species were collected in 2004 and 2006 at six different locations on the estuary. In general, N-Kjedahl, Total Organic Carbon values, salinity and contamination (total trace elements up to 1,000 mg kg−1 As, 6 mg kg−1 Cd, 2,500 mg kg−1 Cu, 1,900 mg kg−1 Pb and 1,300 mg kg−1 Zn) tended to increase downstream of the tidal channel. Soil biochemical properties were not negatively affected either by the high salinity or by trace element contamination. Despite the high values of the trace elements, analysed plant samples showed that Cu was the only metal that could be a serious risk for the food chain.  相似文献   

15.
西太平洋海域海水和雨水的化学特征   总被引:2,自引:0,他引:2  
本工作测定了西太平洋海域中海水、海水悬浮物和海面上雨水的元素组成和浓度。通过富集因子的计算,探讨海面上雨水中微量元素的富集程度及其来源,讨论了海面上气溶胶粒子大小与洗出因子的关系,结果表明不同质量粒径大小的微量元素在公海上具有相似的洗出因子。  相似文献   

16.
Water samples collected in an acid mine impacted watershed indicated that the concentrations of dissolved trace metals were diurnally influenced by mineral saturation, which is controlled primarily by pH and water temperature. Measurements taken suggested that these variations only occur at sample locations immediately downstream from the confluence of acidic and alkaline waters. It is at these locations where initial mineral precipitation occurred and where subtle changes in solubility were most affected, increasing trace metal removal when both the rate of photosynthesis (influencing pH in headwaters) and water temperature were at a maximum. The role of iron photoreduction (increased midday production of ferrous iron) on overall Cu, Mn, and Zn transport was also evaluated, but found to be inconclusive. Iron photoreduction may however influence adsorption and/or coprecipitation of trace metals through associated changes in oxidation state, solubility, and mineralogy of various iron colloids, which are produced upon the neutralization of acidic, metal enriched water. Furthermore, measured values of copper and zinc were compared to relative USEPA chronic criterion for exposure to continuous concentration (CCC) of metals by the calculation of a “toxicity unit” (TU). It was found that average values of both copper and zinc only exceeded the CCC (TU>1) in the acid mine-impacted Leona Creek. In general, zinc toxicity decreased while copper toxicity increased downstream of the confluence of the mine impacted Leona Creek and background Lion Creek (sampled at Lake Aliso), indicating a significant source of zinc in upstream, non mine-impacted samples.  相似文献   

17.
圈养大熊猫乳汁营养成分分析及育幼营养对策初探   总被引:8,自引:2,他引:8  
连续测定了1只10a大熊猫产后1mo内12个乳汁样品中水份、粗蛋白(CP)、粗脂肪(EE)、粗灰分(CA)、乳糖(Lac)、17种氨基酸(AA)、10种矿物元素、6种维生素的含量.结果表明,大熊猫产后前6d乳汁中多数营养素含量与6d后含量差异明显.产后d1乳汁中w(CP)=6.34%,d5~15在5%左右;w(EE)在2.50%~7.33%范围内变动;乳糖含量皆在1%左右;大多数维生素和微量元素含量远高于常见的家畜乳和人乳中相应成分的含量.在分析大熊猫乳汁营养成分含量特点的基础上,探讨了育纳营养对策.  相似文献   

18.
Iodine Deficiency Disorders (IDD) are a common health problem prevalent in the wet zone of Sri Lanka with a prevalence of >25 of the population. In comparison, in the dry zone of Sri Lanka IDD occurs in <10 of the population. Seventy soil samples from 14 villages selected on the basis of the incidence of goitre, were collected and analysed for 13 trace elements using ICP-MS. In order to identify any prevailing differences in antecedent chemical environments, soil samples from each pre-selected village were classified into three groups in terms of their geographical location. Among the elements investigated, the total soil concentrations of Rb, Sr, Ba, Mn and Co are lower in the wet zone of Kalutara. In contrast, total soil Rb, Sr, Ba and Mn contents are higher in the dry zone of Anuradhapura. Further soil total Mo and Nb levels are relatively similar in all pre-selected study locations. The high endemic goitre regions (IDD >25 of the population) show low levels of Rb, Sr, Ba, and Mn and higher levels of V, Cr, Co, Ni, Cu, Zn and Pb as compared with moderate and non-goitre areas. Factor analysis was used to exploit the correlation structure present in data and yielded three groups in all cases. This indicated that most transition group elements and iodine are associated with the Mn phase in the low IDD areas whereas iodine shows a high affinity for the organic phase in high IDD regions. The variable distribution of trace elements, therefore, must be due to differences in mobility and capacity for incorporation into the structure of secondary minerals or organic phases.  相似文献   

19.
The objective of this study is to compare Anyang River bed sediments with water chemical composition and to assess the anthropogenic chemical inputs into the river system. Eight sampling locations were chosen along the river channel. Bed and suspended river sediments and water samples were collected, and analyzed for their chemical and physical composition. Data revealed that trace element concentrations in the river water were generally below world average, except for As, Mn, Ni and Cr. Among the three phases: water, bed and suspended sediment, more than 99% of the trace elements was associated with the bed sediment. Concentrations of trace elements in the sediment were a function a particle size distribution and organic content. The calculated degrees of enrichment based on the least influenced sample (ASD 1) indicated the river sediments were enriched with respect to background. The enrichment factors for Pb, Zn and As were relatively lower than for Cr, Co, Ni and Zn. The difference in the enrichment seems to reflect the human activities influence in the basin, and specially for Cd. Speciation of the elements in the five different chemical forms in the sediment by sequential extraction indicated that the reducible fraction was predominant for Fe, Zinc and Cu showed an irregular variation among the different fractions; whereas, Cd and Pb were more regular. Zinc and Cu highly existed mostly in exchangeable forms. Acid soluble and reducible forms were also important for most metals. The speciation implies that the metals associated with the sediment are subject to release into water bodies as goechemical variables (pH and Eh) change. Currently, the introduced metals are deposited near the source area and are mostly associated with the sediment, implying that the river bed sediment acts mainly as a sink, rather than a pool. The accumulated and enriched toxic trace elements can pose a potential pollution of river water.  相似文献   

20.
In 2000, 63 (polished) white rice samples were collected in eight administrative areas all over South Korea and analyzed for 16 elements by inductively coupled plasma atomic emission spectrometry (ICP-AES). Potassium had the highest content, next to Mg, Ca, Si, Zn, Na, Al and Fe. Most of the samples contained worldwide average concentrations of essential and trace elements in rice grains reported by various researches. For inter-area differences in those elements in the rice, the statistical analysis showed no significant differences (p > 0.05) among the eight administrative areas, suggesting that inter-area differences were not substantial in most cases. Thus, the present data can be used as national background levels of elements in rice produced in South Korea. Using the published data on daily consumption of rice in South Korea, it was possible to estimate the daily intake of As, Cd, Cu, Pb and Zn via rice. The results showed that a regular consumption of rice produced in Korea plays an important role in accumulation of essential and trace elements in Korean, especially for farm-households consuming relatively large amounts of rice.  相似文献   

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