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971.
In the environment of a lead smeltery contamination with lead, zinc and cadmium was measured over a 15-year period. Efficient bag filters were installed in order to remove dust from the flue gases. This measure of improvement resulted in a drastic reduction of lead, zinc and cadmium content in suspended particles (by 92, 94 and 89%), to a lesser extent in depositions (by 79, 75 and 68%), whereas in household dust the reduction was considerably lower (by 53, 55 and 70%). It can be assumed that household dust contains also redispersed soil particles on which the dust from the smeltery flue gases has deposited over years. To determine to what extent contaminated soil continues to cause increased population exposure directly or through plants or pastures, in the period 1981–1985 the content of metallic ions in the soil was measured at three depths. Selective solubility of soil metallic compounds was analysed in water, in 1 mol ammoniumacetate solution and in 0.05 mol ethylenediaminetetra-acetic acid (EDTA) solution in relation to their solubility in suspended particles, depositions and household dust. A considerably low portion of soluble metallic compounds was found in the soil and physico-chemical characteristics of the soil and portion of metallic ions bound to fulvice and humic acids were determined. The behaviour of metallic ions in contact with soil samples was studied in laboratory and it was found that approximately 50% of lead, 70% of zinc and 7% of cadmium ions change into non-soluble or poorly soluble compounds. By qualitative phase analysis in the non-soluble fraction PbO2, Pb3P4O13, Zn(OH)2, ZnO, Fe2O3 and Cd(OH)2 were identified.  相似文献   
972.
The aim was to investigate the toxicity of selected metal oxide nanoparticles (MO-NPs) on the brine shrimp Artemia salina, by evaluating mortality and behavioural and biochemical responses. Larvae were exposed to tin(IV) oxide (stannic oxide (SnO2)), cerium(IV) oxide (CeO2) and iron(II, III) oxide (Fe3O4) NPs for 48 h in seawater, with MO-NP suspensions from 0.01 to 1.0 mg/mL. Mortality and behavioural responses (swimming speed alteration) and enzymatic activities of cholinesterase, glutathione-S-transferase and catalase were evaluated. Although the MO-NPs did not induce any mortality of the larvae, they caused changes in behavioural and biochemical responses. Swimming speed significantly decreased in larvae exposed to CeO2 NPs. Cholinesterase and glutathione-S-transferase activities were significantly inhibited in larvae exposed to SnO2 NPs, whereas cholinesterase activity significantly increased after CeO2 NP and Fe3O4 NP exposure. Catalase activity significantly increased in larvae exposed to Fe3O4 NPs. In conclusion, swimming alteration and cholinesterase activity represent valid endpoints for MO-NP exposure, while glutathione-S-transferase and catalase activities appear to be NP-specific.  相似文献   
973.
The transfer of lead, cadmium, zinc, mercury, copper and molybdenum from soil to the tissues of small mammals inhabiting differently polluted areas in Slovenia was investigated. Metals were determined in soil samples and in the livers of 139 individuals of five small mammal species, collected in 2012 in the vicinity of a former lead smelter, the largest Slovenian thermal power plant, along a main road and in a control area. The area in the vicinity of former lead smelter differs considerably from other study areas. The soil from that area is heavily polluted with Pb and Cd. The mean metal concentrations in the liver, irrespective of species, varied in the following ranges—Pb: 0.40–7.40 mg/kg fw and Cd: 0.27–135 mg/kg fw and reached effect concentrations at which toxic effects can be expected in a significant proportion of the livers of the small mammal specimens (Pb 40 %, Cd 67 %). These findings indicate that the majority of small mammals trapped in the area of the former lead smelter are at risk of toxic effects due to the very high bioaccumulation of Pb and Cd in the organism. On the contrary, Pd and Cd concentrations in the livers of small mammals sampled in the vicinity of the thermal power plant and along the main road were comparable with reference values and considerably lower than effect concentrations. Additionally, the study suggests that Apodemus flavicollis and Myodes glareolus are very suitable biomonitors of metal pollution.  相似文献   
974.
The occurrence and severity of harmful cyanobacterial or blue-green algal blooms (HABs) have increased in recent decades, posing a serious threat of illness to humans. In some countries, water contaminated with cyanotoxins that is used for drinking or haemodialysis has posed a particularly serious risk. However, it is now recognized that recreational exposure to natural toxins by skin contact, accidental swallowing of water or inhalation can also cause a wide range of acute or chronic illnesses. In this review, we focus on the importance of cyanotoxin management in recreational waters. The symptoms related with HAB poisonings, the recommended safety concentrations limit for cyanobacteria and cyanotoxins in such waters, as well as early health hazard indicators of their presence and their monitoring are all discussed. We also present in this review an overview of the methods developed in recent decades for eliminating cyanobacteria and the toxic compounds that they produce.  相似文献   
975.
Arsenic distribution in water/sediment system of Sevojno   总被引:1,自引:0,他引:1  
Arsenic is a toxic and carcinogenic element. Its toxicity depends on its oxidation state and its concentration. The aim of this paper is to determine, for the first time, the concentration levels of arsenic in water and sediment during the spring/summer period of 2009 in Sevojno, a region in West Serbia with a long industrial tradition, as well as to determine the model of arsenic distribution in water/sediment system and the level of its compatibility with the existing theoretical model. Adsorption is a continual process in the environment. It plays a very important role in the transport and fate of pollutants, especially in sediment. The adsorption of arsenic was examined using the Freundlich adsorption isotherm.  相似文献   
976.
Although there are tendencies to develop a single common index which would describe an overall air quality status within an area, constructed from a choice of measurements of individual pollutants, indices describing individual pollutants themselves have several potentials which can be used in ways which are not possible with pollutant concentrations. On the case of Belgrade, Serbia, we investigated possibilities of using such indices for comparisons between pollutants, characterization of monitoring sites, and extending their use to include elements of population exposure. A methodology of adjusting the results obtained at monitoring stations located in severe pollution conditions, like street canyons, is proposed and used.  相似文献   
977.
Considering growing population and decreasing mineral resource reserves, the issue of undermining has been and shall remain very topical. This study aims to identify the mutual connections between mined out panels of a deposit and the final manifestations on the ground surface related to deep black coal mining. On the grounds of the identified connections, the study describes a method to simplify a common evaluation of undermined areas according to building site categories. Within the study, a demarcation of the areas was conducted in two localities in Czech Republic influenced by the effects of undermining in the Upper-Silesian Basin. In the allotment of the CSM Mine, an area unsuitable for founding structures was defined from the centre of the worked out workings to the distance of 175 m from the panel's edge, for which the corresponding break angle is 78.3°. Similarly, in the allotment of the Paskov Mine, an area unsuitable for founding structures was determined to the distance of 500 m from the panel's edge, for which the corresponding break angle is 50.2°. This demarcation may be implemented prior to deposit mining being aware of several physical-mechanical parameters of rocks in the deposit's overburden. Having mined out a particular section of a deposit, it is recommended to verify the values of break angle using the method described herein. The study may be applied as a relatively fast and effective method to evaluate future land use for planning.  相似文献   
978.
979.
In this study concentrations of metals in the native plants and soils surrounding the old flotation tailings pond of the copper mine were determined. It has been established that the soil is heavily contaminated with copper, iron and arsenic, the mean concentrations being 1585.6, 29,462.5 and 171.7 mg kg(-1) respectively. All the plants, except manganese, accumulated metallic elements in concentrations which were either in the range of critical and phytotoxic values (Pb and As) or higher (Zn), and even much higher (Cu and Fe) than these values. Otherwise, the accumulation of Mn, Pb and As was considerably lower than that of Cu, Fe and Zn. In most plants the accumulation of target metals was highest in the root. Several plant species showed high bioaccumulation and translocation factor values, which classify them into species for potential use in phytoextraction. The BCF and TF values determined in Prunus persica were 1.20 and 3.95 for Cu, 1.5 and 6.0 for Zn and 1.96 and 5.44 for Pb. In Saponaria officinalis these values were 2.53 and 1.27 for Zn, and in Juglans regia L. they were 8.76 and 17.75 for Zn. The translocation factor in most plants, for most metals, was higher than one, whereas the highest value was determined in Populus nigra for Zn, amounting to 17.8. Among several tolerant species, the most suitable ones for phytostabilization proved to be Robinia pseudoacacia L. for Zn and Verbascum phlomoides L., Saponaria officinalis and Centaurea jacea L. for Mn, Pb and As.  相似文献   
980.
The purpose of this study was to examine the levels of trace elements and to discuss the origin and mobility of these contaminants in the canal sediments (alluvial formation of the Danube River). The most significant fractions binding all of the studied elements were oxides and silicates. The high proportion of elements in the residual fraction and the generally low contents of extractable elements reflected the background geochemical conditions. The contents of trace elements (except Hg and As) were dominantly controlled by the presence of Fe and Mn oxides as well as by the grain size and the geochemical composition of the sediment. The studied alluvial sediments were not heavily contaminated; there were only few sites where an anthropogenic influence on the concentrations of some metals (Cu, Cd, Zn, and Pb) was noticed. The results from this study show that impact of Pan?evo industrial zone on the quality of the Danube River and its contamination with trace element is minor.  相似文献   
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