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141.

The aim of the study was to evaluate the content, occurrence, and leachability of arsenic (As), lead (Pb), and thallium (Tl) in wastes from coal cleaning processes with respect to the safe management of this waste. The study focused on wastes resulting from the wet gravitation and flotation processes employed for the purposes of coking coal cleaning in four coal mines situated in the Upper Silesian Coal Basin (Poland). The scope of the study included (i) determination of the content of these elements in the investigated wastes using atomic absorption spectrometry, (ii) evaluation of their mode of occurrence using electron microprobe analysis, and (iii) preliminary assessment of their leachability in deionized water. The content of the analyzed elements in the examined samples of coal waste was twice as high as the average content of these elements in the Earth’s crust. The contents of As and Pb, however, did not exceed their permissible contents in inert waste in accordance with Polish legal regulations based on EU directives. The limit on the content of Tl is not specified by these regulations, but its amount in the examined samples was similar to that occurring in the soils. Moreover, leaching tests have shown that these elements are hardly eluted from the analyzed material. Their content in the water leachates was generally lower than the detection limit of the analytical method, complying with the standards for good and very good water quality. Low leachability of these elements most probably results from their mode of occurrence in the investigated wastes. The chemical analysis using an electron microprobe and the analysis of the correlation between these elements, e.g., total and pyritic sulfur, have shown that Pb, As, and Tl are mainly found in sulfide minerals which are characterized by negligible solubility. In conclusion, the investigated hard coal processing waste does not constitute a threat to the environment and can be commercially used or safely neutralized, e.g., by landfilling.

  相似文献   
142.
Floods in the northern foreland of the Tatra Mountains considerably contribute to the total flood damage in Poland. Therefore, the question whether the magnitude and frequency of floods have changed in this region is of high interest. This study aims at investigating the inter-decadal variability of magnitude, frequency and seasonality of floods since the mid-twentieth century, to better understand regional changes. The analysis was accomplished in a multi-temporal approach whereby trends are fitted to every possible combination of start and end years in a record. Detected trends were explained by estimating correlations between the investigated flood parameters and different large-scale climate indices for the northern hemisphere, and by trends found in intense precipitation indices, number of days with snow cover, cyclonic circulation types, temperature and moisture conditions. Catchment and channel changes that occurred in the region over the past decades were also considered. Results show that rivers in the area exhibit considerable inter-decadal variability of flows. The magnitude and direction of short-term trends are heavily influenced by this inter-decadal variability; however, certain patterns are apparent. More extreme, although perhaps less frequent floods are now likely to occur, with a shift in the seasonality, decreasing flood magnitudes in winter and increasing during autumn and spring. The identification of the factors contributing to the occurrence of flood events and their potential changes is valuable to enhance the flood management in the region and to improve the resilience of the population in this mountainous area.  相似文献   
143.
144.
The common occurrence of organochlorine compounds in the environment, food and human tissues may constitute a serious threat to human health. The method of gas chromatography-mass spectroscopy was used to determine the content of pesticides in 15 samples of raw cow's milk from different regions of Poland. The results revealed high levels of p,p′-DDE, p,p′-DDT, heptachlor and aldrin. The studied milk contained lindane in average concentrations within the maximum limits. Although in 20% of all samples tested, the concentration of lindane exceeded permissible limits, while in 15% of samples the content of Σ DDT was too high. But the average daily consumption of milk containing organochlorine pesticides poses no direct threat to human health, because daily intake (DI) for all compounds were below the acceptable daily intake (ADI). Attention should be paid to the exposure of consumers to pesticide residues from other dairy foods.  相似文献   
145.
The carpophores of Parasol Mushroom and underlying soil substrate collected from several unpolluted and spatially distant sites across Poland were examined to know content and bioconcentration potential of mercury by this species. The total mercury content of the caps of Parasol Mushroom for the particular sites ranged from 1.1 ± 1.0 to 8.4 ± 7.4 μ g/g dry matter (total range from 0.05 to 22 μ g/g dm), while in the stalks were from 0.53 ± 0.27 to 6.8 ± 7.1 μ g/g dm (total range from 0.078 to 20 μ g/g dm). A top soil layer (0–10 cm) showed baseline mercury concentration from 0.022 ± 0.011 to 0.36 ± 0.16 μ g/g dm (total range from 0.010 to 0.54 μg/g dm). Parasol Mushroom is an effective mercury accumulator in the carpophores and bioconcentration factor (BCF) values of this element in the caps and depending on the sampling site ranged from 16 ± 6 to 220 ± 110 (total range from 0.52 to 470), while for the stalks were from 7.6 ± 2.6 to 130 ± 96 (total range from 0.52 to 340). It seems reasonable to state that tolerance (maximum allowable concentration) of the total mercury in a single cap of Parasol Mushroom at unpolluted areas should not exceed 25 μ g/g dm. A value greater then 25 μ g/g dm will imply an elevated content due to site pollution problems. Nevertheless, knowledge on highly toxic methylmercury content and its fraction in the total mercury content of Parasol Mushroom is lacking.  相似文献   
146.
Various statistical methods have been employed to analyse in details seasonal diversification of polychlorinated biphenyl (PCB)/polybrominated diphenyl ether (PBDE) congener profiles found in butter fat. The variability of the PCB/PBDE congener profiles indicates the presence of various sources of the milk fat contamination. The obtained results suggest that the environmental chemical background has the highest share in the contamination sources pattern. Ion trap mass spectrometry coupled to high-resolution gas chromatography with semi-permeable membrane dialysis sample cleanup was used for determination of PCBs and PBDEs in milk fat. Determined butter fat PCB profiles were similar to the profiles characteristic for Aroclor 1254 technical mixture. Our data indicate that dietary intake of PCB/PBDE with milk and milk products may be estimated to be about 717.5 pg kg b.w.?1 day?1 for six-indicator PCBs, 0.329 (equivalent toxicity, TEQ) pg kg b.w.?1 day?1 for 12 DL PCBs and 50 pg kg b.w.?1 day?1 for PBDEs (sum of 14 congeners).  相似文献   
147.
Recycling and reducing household waste are political goals internationally, nationally and locally. In Sweden, households in apartment buildings seem to sort their waste to a lesser extent than households in single-family houses. This paper analyses the challenges of the diffusion of a new waste management system in apartment buildings, and focuses on a municipal housing company and the actions of its area managers. It is argued that area managers can be regarded as street-level bureaucrats who act as ‘collectors’ of tenants’ everyday practices in the studied implementation process. The study is based on interviews, document analysis and observations.  相似文献   
148.
The paper presents the results of determination of volatile organohalogen compounds (VOX) in urine samples from subjects exposed to these compounds in their workplaces and through consumption of chlorinated tap water. The analytes were isolated and preconcentrated from the complex urine samples using the thin layer headspace (TLHS) technique with autogenous generation of the liquid sorbent. Final gas chromatographic determination was carried out by direct aqueous injection with electron capture detection (DAI-ECD). The results indicate that only a small fraction (<4%) of the VOX input is excreted with urine in the non-metabolized form. A positive correlation was found between the occupational levels of VOX in the workplace and their levels in urine. VOX levels in the urine of subjects not exposed to them in the workplace were significantly lower. Their presence in the organisms was most probably related to consumption of tap water produced by chlorination of surface waters.  相似文献   
149.
Existing data on metal concentrations in mussels from subarctic, temperate, subtropical and tropical waters were analyzed using multivariate statistics in order to assess regional variations in metal contamination. Potential errors were reduced by only analyzing data from surveys that employed the same protocols, analytical methodologies and analysts. Factor analysis demonstrated that mussels inhabiting extremely contaminated areas (e.g. from Japanese and Swedish metallurgy sources) could be separated from mussels from other contaminated areas, and that metals such as Cd, Pb, Cu and Zn could be used to identify heavily contaminated samples while Co, Fe, Cr and Ni concentrations were good markers for exposure to inputs from different industrial sources. Furthermore byssus, like soft tissue, selectively and sensitively reflects variations of certain metal concentrations in ambient waters and thus serves as a reliable biomonitor for these contaminants in a variety of coastal and estuarine areas.  相似文献   
150.
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