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171.
This study modeled the impact on freshwater ecosystems of pharmaceuticals detected in biosolids following application on agricultural soils. The detected sulfonamides and hydrochlorothiazide displayed comparatively moderate retention in solid matrices and, therefore, higher transfer fractions from biosolids to the freshwater compartment. However, the residence times of these pharmaceuticals in freshwater were estimated to be short due to abiotic degradation processes. The non-steroidal anti-inflammatory mefenamic acid had the highest environmental impact on aquatic ecosystems and warrants further investigation. The estimation of the solid-water partitioning coefficient was generally the most influential parameter of the probabilistic comparative impact assessment. These results and the modeling approach used in this study serve to prioritize pharmaceuticals in the research effort to assess the risks and the environmental impacts on aquatic biota of these emerging pollutants.  相似文献   
172.
Solid phase microextraction (SPME) is a fast, cheap and solvent free methodology widely used for environmental analysis. A SPME methodology has been optimized for the analysis of VOCs in a range of matrices covering different soils of varying textures, organic matrices from manures and composts from different origins, and biochars. The performance of the technique was compared for the different matrices spiked with a multicomponent VOC mixture, selected to cover different VOC groups of environmental relevance (ketone, terpene, alcohol, aliphatic hydrocarbons and alkylbenzenes). VOC recovery was dependent on the nature itself of the VOC and the matrix characteristics. The SPME analysis of non-polar compounds, such as alkylbenzenes, terpenes and aliphatic hydrocarbons, was markedly affected by the type of matrix as a consequence of the competition for the adsorption sites in the SPME fiber. These non-polar compounds were strongly retained in the biochar surfaces limiting the use of SPME for this type of matrices. However, this adsorption capacity was not evident when biochar had undergone a weathering/aging process through composting. Polar compounds (alcohol and ketone) showed a similar behavior in all matrices, as a consequence of the hydrophilic characteristics, affected by water content in the matrix. SPME showed a good performance for soils and organic matrices especially for non-polar compounds, achieving a limit of detection (LD) and limit of quantification (LQ) of 0.02 and 0.03 ng g−1 for non-polar compounds and poor extraction for more hydrophilic and polar compounds (LD and LQ higher 310 and 490 ng g−1). The characteristics of the matrix, especially pH and organic matter, had a marked impact on SPME, due to the competition of the analytes for active sites in the fiber, but VOC biodegradation should not be discarded in matrices with active microbial biomass.  相似文献   
173.
Eutrophication is an ongoing process in most parts of the Baltic Sea. This article reports on the changes during recent decades of several eutrophication-related variables in the open sea areas surrounding Finland (wintertime nutrient concentrations, wintertime nutrient ratios, and summer time chlorophyll alpha concentrations at the surface). The sum of nitrate- and nitrite-nitrogen ([NO3+NO2]-N) was observed to increase nearly fourfold in the Northern Baltic Proper and the Gulf of Finland and almost double in the Bothnian Sea from the 1960s until the 1980s or 1990s. The increase was followed by a decrease, which was modest in the two former subregions. Phosphate-phosphorus (PO4-P) concentrations followed a similar pattern in the Northern Baltic Proper (threefold increase and subsequent slight decrease) and Bothnian Sea (30% increase and subsequent decrease), but increased throughout the study in the Gulf of Finland, with the present concentration being threefold to the measurements made in the early 1970s. The PO4-P concentration decreased throughout the study in the Bothnian Bay. Silicate-silicon (SiO4-Si) concentrations decreased 30-50% from the early 1970s to the late 1990s and increased 20-40% thereafter in the Northern Baltic Proper, the Gulf of Finland, and the Bothnian Sea. Chlorophyll alpha showed an increase of over 150% in the Northern Baltic Proper and the Gulf of Finland from the 1970s until the early 2000s. In the Bothnian Sea the chlorophyll alpha concentration increased more than 180% from the late 1970s until the late 1990s, and decreased thereafter. According to these long-term observations, the Gulf of Finland and Northern Baltic Proper show clear signs of eutrophication, which may be emphasized by hydrographical changes affecting the phytoplankton communities and thus the algal biomass.  相似文献   
174.
In the frame of the international SOILSAMP project, funded and coordinated by the National Environmental Protection Agency of Italy (APAT), uncertainties due to field soil sampling were assessed. Three different sampling devices were applied in an agricultural area using the same sampling protocol. Cr, Sc and Zn mass fractions in the collected soil samples were measured by k(0)-instrumental neutron activation analysis (k(0)-INAA). For each element-device combination the experimental variograms were calculated using geostatistical tools. The variogram parameters were used to estimate the standard uncertainty arising from sampling. The sampling component represents the dominant contribution of the measurement uncertainty with a sampling uncertainty to measurement uncertainty ratio ranging between 0.6 and 0.9. The approach based on the use of variogram parameters leads to uncertainty values of the sampling component in agreement with those estimated by replicate sampling approach.  相似文献   
175.
In this work, 24-h PM10 samples were collected in Rio de Janeiro, Brazil, and analysed for trace elements (Cd, Ce, Cu, La, Mo, Ni, Pb, Pd, Rh, Sb and Sn). The sampling was carried out at five locations (Bonsucesso; Centro, downtown city; Copacabana; Nova Igua?u and Sumaré) with different traffic densities and anthropogenic activities. An analytical method based on the EPA method for the determination of trace elements in airborne particulate matter (PM), using ultrasonic-assisted extraction and inductively coupled plasma mass spectrometry (ICP-MS) was applied. Our results suggest that vehicular traffic is the most important source of environmental pollution at the studied sites. The presence of Mo, Pd and Rh in the analysed filters reflects an additional source of pollution caused by the erosion and deterioration of automotive catalytic converters.  相似文献   
176.
A coupled solar photo-Fenton (chemical) and biological treatment has been used to remove biorecalcitrant diuron (42 mg l(-1)) and linuron (75 mg l(-1)) herbicides from water at pilot plant scale. The chemical process has been carried out in a 82 l solar pilot plant made up by four compound parabolic collector units, and it was followed by a biological treatment performed in a 40 l sequencing batch reactor. Two Fe(II) doses (2 and 5 mg l(-1)) and sequential additions of H2O2 (20 mg l(-1)) have been used to chemically degrade the initially polluted effluent. Next, biodegradability at different oxidation states has been assessed by means of BOD/COD ratio. A reagent dose of Fe=5 mg l(-1) and H2O2=100 mg l(-1) has been required to obtain a biodegradable effluent after 100 min of irradiation time. Finally, the organic content of the photo-treated solution has been completely assimilated by a biomass consortium in the sequencing batch reactor using a total suspended solids concentration of 0.2 g l(-1) and a hydraulic retention time of 24h. Comparison between the data obtained at pilot plant scale (specially the one corresponding to the chemical step) and previously published data from a similar system performing at laboratory scale, has been carried out.  相似文献   
177.
Two drinking water production plants located in North Italy, collecting water from the River Po (Plants 1 and 2) were chosen for this study. Water samples were collected before and after the disinfection process and at two points along the piping system. Water samples were concentrated by the solid-phase extraction system and injected intraperitoneally into specimens of Cyprinus carpio. The concentration of water samples was 3 l/equiv. In order to assess the effects of the water samples on carp liver, total glutathione and glutathione-dependent enzymes, such as glutathione S-transferase, glutathione peroxidase, glutathione reductase and glyoxalase I, were measured following this treatment for 6 days at two experimental times (3 and 6 days). Both water plant-treated carp showed a general increase of the enzymatic activities of glutathione S-transferase, and glutathione reductase which might be employed as potential biomarkers of oxidative stress induced by disinfected river water. Plant 1-treated carp showed higher glyoxalase I and glutathione levels and lower glutathione peroxidase activity. A depleted level of total glutathione and of glyoxalase I for specimens of water plant 2 (for both experimental times), without correlation with the distances in the pipeline, suggests that river plant water can also lead to potentially adverse effects on selected biochemical parameters in C. carpio.  相似文献   
178.
In order to characterize the different sources of exposure to arsenic (As), urinary excretion of total As, the sum of inorganic As+MMA+DMA determined by the hydride generation-atomic absorption spectrophotometry technique, and the species As(3), As(5), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA) and arsenobetaine were determined in 49 workers at a steel foundry, with presumed occupational exposure to As, and 50 subjects from the general population, all males. No evidence of occupational exposure to As resulted from environmental monitoring performed in the foundry, although the analysis of minerals used as raw materials showed the presence of As, particularly in fossils and fine ores. The urinary concentrations of As(3), MMA, DMA, the sum of inorganic As+MMA+DMA and total As were not different in the two groups, while arsenobetaine appeared significantly higher in the controls than in the workers. The different species of urinary As were all significantly correlated. Urinary excretion of As(3) was associated with the consumption of mineral water and with residence in an industrial zone, while MMA, DMA, arsenobetaine, the sum of inorganic As+MMA+DMA and total As urinary excretion were associated with the consumption of crustaceans and/or shellfish 3 days or less before urine collection. Multiple regression analysis confirmed these results. In conclusion, in populations with a high consumption of seafood, living in areas characterized by coastal/marine As pollution, only speciation of As can identify a prevalent role of environmental sources, like the consumption of seafood contaminated by As, in determining urinary As excretion, and exclude an occupational origin of the exposure.  相似文献   
179.
In this work, it has been studied the use of conductive-diamond electrochemical oxidation (CDEO) as a refining technology to assure the quality of the effluents of door manufacturing processes (DMP). To do this, the raw effluents of these factories have been treated by a combination of physicochemical, biological and CDEO treatments. CDEO was found to be a feasible alternative to the refinement of a wooden DMP waste. It can successfully decrease the organic load of the effluents of the biological oxidation with low energy requirements. In addition, in case of incidents in the biological process, CDEO can treat successfully the effluents of the coagulation process. The effluents of the biological treatment have also been treated by CDEO in order to check the possible use of electrochemical technology to increase the biodegradability of the effluents and their possible recycle to the biological treatment. Unfortunately, electrochemical technology was found to be not adequate to increase the biodegradability of the effluents of a biological treatment. The hard oxidation conditions generated during CDEO do not lead to the accumulation of intermediates but to the almost direct formation of carbon dioxide. Lowering the current density or changing the electrodes can not enhance the biodegradability of the effluents of an electrochemical cell.  相似文献   
180.
This study tests an alternative method to the traditional unhairing method used during the process of tanning the hides. The new method is based on the substitution of sodium sulfide by hydrogen peroxide as an unhairing agent in both hair recovery and recirculation of the floats employed in the process. The properties of the hides obtained using the two methods have been compared and the results indicate that those hides have similar physical, chemical, and organoleptic properties. However, the differences existing from an environmental point of view are significant. These include reductions of water consumption (approx 70%), chemical oxygen demand (approx 35%), toxicity (98%) and total kjendhal nitrogen (50%). Also, the risk associated with the production of hydrogen sulfide is eliminated, which implies a great improvement in terms of safety for the workers. Given the large amounts of water and chemical pollution discharged in the process, the reductions in absolute values represent a significant improvement. A financial assessment was carried out to demonstrate that the proposed new system is 16% more economic than the traditional one.  相似文献   
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