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131.
132.
The paper presents the analysis of anthropogenical modifications of the landscape in relation to the course and consequences of floods. The research was conducted in the Otava river basin which represents the core zone of the extreme flood in August 2002 in Central Europe. The analysis was focused on the key indicators of landscape modification potentially affecting the runoff process - the long-term changes of land-use, changes of land cover structure, land drainage, historical shortening of the river network and the modifications of streams and floodplains. The information on intensity and spatial distribution of modifications was derived from different data sources - historical maps, available GIS data, remote sensing and field mapping. The results revealed a high level of spatial diversity of anthropogenical modifications in different parts of the river basin. The intensive modifications in most of indicators were concentrated in the lowland region of the river basin due to its agricultural use; however important changes were also recorded in the headwater region of the basin. The high spatial diversity of the modifications may result in their varying effect on the course and consequences of floods in different parts of the river basin. This effect is demonstrated by the cluster analysis based on the matrix of indicators of stream and floodplain modification, physiogeographical characteristics and geomorphological evidences of the flood in August 2002, derived from the individual thematic layers using GIS.  相似文献   
133.
Secondary metabolites produced by fungi and bacteria are among the potential agents that contribute to adverse health effects observed in occupants of buildings affected by moisture damage, dampness and associated microbial growth. However, few attempts have been made to assess the occurrence of these compounds in relation to moisture damage and dampness in buildings. This study conducted in the context of the HITEA project (Health Effects of Indoor Pollutants: Integrating microbial, toxicological and epidemiological approaches) aimed at providing systematic information on the prevalence of microbial secondary metabolites in a large number of school buildings in three European countries, considering both buildings with and without moisture damage and/or dampness observations. In order to address the multitude and diversity of secondary metabolites a large number of more than 180 analytes was targeted in settled dust and surface swab samples using liquid chromatography/mass spectrometry (LC/MS) based methodology. While 42%, 58% and 44% of all samples collected in Spanish, Dutch and Finnish schools, respectively, were positive for at least one of the metabolites analyzed, frequency of detection for the individual microbial secondary metabolites - with the exceptions of emodin, certain enniatins and physcion - was low, typically in the range of and below 10% of positive samples. In total, 30 different fungal and bacterial secondary metabolites were found in the samples. Some differences in the metabolite profiles were observed between countries and between index and reference school buildings. A major finding in this study was that settled dust derived from moisture damaged, damp schools contained larger numbers of microbial secondary metabolites at higher levels compared to respective dust samples from schools not affected by moisture damage and dampness. This observation was true for schools in each of the three countries, but became statistically significant only when combining schools from all countries and thus increasing the sample number in the statistical analyses.  相似文献   
134.
The aim of this study was to test if pharmaceuticals could explain observed responses of field collected and transplanted invertebrate species (Hydropsyche exocellata, Echinogammarus longisetosus, and Daphnia magna). The study was performed in the middle and lower course of Llobregat river basin, which is affected by pharmaceuticals and other pollutants coming from sewage treated effluents. Up to 10 different endpoints including enzyme activities related with detoxication mechanisms (i.e. glutathione S transferase, catalase, esterases), the oxidative stress damage marker (lipid peroxidation), and individual responses (mortality, post-exposure feeding rates) were assessed. Biological responses were complemented with a detailed chemical analysis of metals, detergents, pesticides, pharmaceuticals and other general water quality variables to allow identifying causal abiotic factors. Estimated hazard indexes of measured pollutants indicated that pesticides and metals accounted for most of the predicted toxicity (>95%) in the most contaminated site and that the predicted toxicity of pharmaceuticals was marginal (<5%). The three species showed a clear impact across the studied gradient indicated by higher levels of feeding inhibition and of mortality towards lower reaches. Specific responses such as inhibition of cholinesterase activities were closely related to high and presumable toxic levels of diazinon, whereas unspecific responses such as enhanced levels of antioxidant defensive mechanism and of lipid peroxidation levels were associated with most pollutant classes as well as with high and presumable toxic levels of salt and ammonia. These results indicate that pesticides, salinity, ammonia probably had greater effects on the studied species than pharmaceuticals.  相似文献   
135.
The residues of antineoplastic drugs are considered as new and emerging pollutants in aquatic environments. Recent experiments showed relatively high toxicity of 5-fluorouracil (5-FU), imatinib mesylate (IM), etoposide (ET) and cisplatin (CP) that are currently among most widely used antineoplastic drugs, against phytoplankton species. In this study, we investigated the toxic potential of the mixture of 5-FU?+?IM?+?ET against green alga Pseudokirchneriella subcapitata and cyanobacterium Synechococcus leopoliensis, and the stability and sorption of these drugs to algal cells. Toxic potential of the mixture was predicted by the concepts of ‘concentration addition’ and ‘independent action’ and compared to the experimentally determined toxicity. In both test species, the measured toxicity of the mixture was at effects concentrations EC10–EC50 higher than the predicted, whereas at higher effect concentration (EC90), it was lower. In general, P. subcapitata was more sensitive than S. leopoliensis. The stability studies of the tested drugs during the experiment showed that 5-FU, IM and CP are relatively stable, whereas in the cultures exposed to ET, two transformation products with the same mass as ET but different retention time were detected. The measurements of the cell-linked concentrations of the tested compounds after 72 h exposure indicated that except for CP (1.9 % of the initial concentration), these drugs are not adsorbed or absorbed by algal cells. The results of this study showed that in alga and cyanobacteria exposure to the mixture of 5-FU?+?ET?+?IM, in particular at low effect concentration range, caused additive or synergistic effect on growth inhibition, and they suggest that single compound toxicity data are not sufficient for the proper toxicity prediction for aquatic primary producers.  相似文献   
136.

Purpose  

The Llobregat River, which is characterized by important fluctuations of the flow rates, receives treated waters from WWTPs. During the years 2007 and 2008, the Llobregat River basin suffered from a severe drought which affected the supply of drinking water facilities (DWF) that rely on the exploitation of the river water. The Catalan Water Agency implemented a water reuse experiment with the objective of maintaining the river flow rate at sufficiently high level so as to ensure the supply of raw water to Barcelona’s major DWF.  相似文献   
137.

Introduction  

Mediterranean rivers are characterized by a high flow variability, which is strongly influenced by the seasonal rainfall. When water scarcity periods occur, water flow, and dilution capacity of the river is reduced, increasing the potential environmental risk of pollutants. On the other hand, floods contribute to remobilization of pollutants from sediments. Contamination levels in Mediterranean rivers are frequently higher than in other European river basins, including pollution by pharmaceutical residues. Little attention has been paid to the transport behavior of emerging contaminants in surface waters once they are discharged from WWTP into a river. In this context, this work aimed to relate presence and fate of emerging contaminants with hydrological conditions of a typical Mediterranean River (Llobregat, NE Spain).  相似文献   
138.
The incidence of testicular cancer (TC) has been increasing worldwide during the last decades. The reasons of the increase remains unknown, but recent findings suggest that organochlorine pesticides (OPs) could influence the development of TC. A hospital-based case-control study of 50 cases and 48 controls was conducted to determine whether environmental exposure to OPs is associated with the risk of TC, and by measuring serum concentrations of OPs, including p,p’-dichlorodiphenyldichloroethylene (p,p’-DDE) isomer and hexachlorobenzene (HCB) in participants. A significant association was observed between TC and household insecticide use (odds ratio [OR] = 3.01, 95 % CI: 1.11-8.14; ORadjusted = 3.23, 95 % CI: 1.15-9.11). Crude and adjusted ORs for TC were also significantly associated with higher serum concentrations of total OPs (OR = 3.15, 95 % CI: 1.00-9.91; ORadjusted = 3.34, 95 % CI: 1.09-10.17) in cases compared with controls. These findings give additional support to the results of previous research that suggest that some environmental exposures to OPs may be implicated in the pathogenesis of TC.  相似文献   
139.
The partitioning of alkylphenols in the dissolved and particulate matter of influents, effluents, accumulation onto sludge and the impact of sewage treatment plant upon receiving waters was studied along the Ter River basin (Catalonia, NE Spain). A solid-phase extraction or pressurized liquid extraction followed by liquid chromatography-mass spectrometry was developed and permitted to determine target compounds with high efficiency in waters, particulate material and sludge. Nonylphenol mono- and diethoxylate, nonylphenol and octylphenol partitioned preferably upon particulate matter and sludge, whereas long chain NPE(3-15)O prevailed in the dissolved phase and was released by effluents. Within the treatment process, a net accumulation of alkylphenols in sludge was found, producing up to 148g/t/month. The removal efficiency of alkylphenols was of 37-90% and depended on the treatment. Assessment on the fate of these contaminants within STPs is discussed in terms of flow rates, biological oxygen demand and tons of sludge produced.  相似文献   
140.
In the present work, a novel and simple detection system for As inorganic species contained in groundwater is presented. To reach the required detection limit, the proposed methodology is based on two steps: first is the transport and preconcentration of the inorganic arsenic species using a polymer inclusion membrane (PIM) system and second is the formation of a coloured complex, the  absorbance of which is measured. Different parameters related to the membrane composition and the transport kinetics have been studied, and it was found that membranes made of polyvinyl chloride (PVC) as a polymer, and Aliquat 336 as a carrier, ensured efficient arsenic transport when the carrier content was at least 31 % (w/w). The implementation of the designed PIM in a special device that contained only 5 mL of the stripping solution (0.1 M NaCl) allowed As preconcentration from a 100-mL water sample, thus facilitating its detection with the colorimetric method. The new method developed here was validated, and its analytical figures of merit were determined, i.e. limit of detection of 4.5 μg L?1 at 820 nm and a relative standard deviation within the range 8–10 %. Finally, the method was successfully applied to the analysis of different water samples from Catalonia region with naturally occurring As.  相似文献   
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