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The hydrocarbon composition of atmospheric particulate matter from A Coruna city (Northwest Spain) has been studied. TSP (total suspended particulate) and PM_(10) (particulate matter with aerodynamic diameter <10 mu m) samples were taken over 7 and 4 months at two stations located in residential and industrial sectors of A Coruna city, respectively. The levels of hydrocarbons found in atmospheric particulate samples of A Coruna city are higher than the ones found in other cities over the world. Ratios between the analysed compounds and their sources were established. Both anthropogenic and biogenic origins were found....
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The hydrocarbon composition of atmospheric particulate matter from A Coruna city (Northwest Spain) has been studied. TSP (total suspended particulate) and PM_(10) (particulate matter with aerodynamic diameter <10 mu m) samples were taken over 7 and 4 months at two stations located in residential and industrial sectors of A Coruna city, respectively. The levels of hydrocarbons found in atmospheric particulate samples of A Coruna city are higher than the ones found in other cities over the world. Ratios between the analysed compounds and their sources were established. Both anthropogenic and biogenic origins were found.
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Oxygenated polycyclic aromatic hydrocarbons (oxy-PAH) and sulphurated polycyclic aromatic hydrocarbons (S-PAH) formation during pyrolysis experiments of mixtures of ethylene (3%) and several SO2 concentrations (0.3 to 1%), at diff...
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Oxygenated polycyclic aromatic hydrocarbons (oxy-PAH) and sulphurated polycyclic aromatic hydrocarbons (S-PAH) formation during pyrolysis experiments of mixtures of ethylene (3%) and several SO2 concentrations (0.3 to 1%), at different reaction temperatures (1075 to 1475 K), was studied. The sixteen EPA-PAH priority pollutants, classified by the Environmental Protection Agency (EPA), were also analyzed. Oxy-PAH, S-PAH and EPA-PAH were jointly identified and quantified by gas chromatography mass spectrometry (GC-MS). Soot formation and the main gases concentration at the gas reactor outlet were also analyzed. The main results showed that oxy-PAH, S-PAH and EPA-PAH were formed in all the experiments carried out. Both ratios, oxy-PAH/EPA-PAH and S-PAH/EPA-PAH, were found to increase with the temperature and with the SO2 inlet concentration.
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Contamination of agroecosystems with PAHs may effect an ability of a soil to sustain a natural biocenosis or agriculture and create a toxicological risk to plants cultivated in the area. The aim of this study was to evaluate the e...
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Contamination of agroecosystems with PAHs may effect an ability of a soil to sustain a natural biocenosis or agriculture and create a toxicological risk to plants cultivated in the area. The aim of this study was to evaluate the ecotoxicological activity of soils polluted with PAHs with the repect to their effect on plants. Three different soils (chernozem, rendzia and brown soil) artificially contaminated with the mixture of four PAH compounds (fluorene, anthracene, pyrene and chrysene) at the levels of ∑4PAHs of 1, 10, 50 and 100 mg kg~-1 were used in the study (laboratory bioassays)
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There is worldwide concern about the pollution caused by libration of stable hydrocarbon in the environment, both from industrial activities and from accidental spill of oil, faciliate the source of considerable polycyclic aromati...
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There is worldwide concern about the pollution caused by libration of stable hydrocarbon in the environment, both from industrial activities and from accidental spill of oil, faciliate the source of considerable polycyclic aromatic hydrocarbon (PAH) contamination. In recent years, attention has to be made for degradation of these contaminations . In this context, Biosurfactants plays a major role. Biosurfactant are the surface active molecules synthesized by microorganism and produced extracellular or on cell surface. They are amphipatic in nature containing both hydrophobic and hydrophilic moiety. The use and commercial application of biosurfactant has increased during the past decade, such as, in food industries, bioremediation of PAH, enhanced oil recovery, cosmetics, therapeutics (immunosuppressive, antibacterial, antifungal and antiviral). Biosurfactant are glycolipids, Lipopetide and lipoprotein, fatty acid, neutral lipid and phospholipids, polymeric and particulate in nature. They are biodegradable, low toxic, biocompatible, stable at extreme pH and temperature. The demands of these biomolecule are increasing day by day due to large application and having unique properties. Hence industrial processes are being developed for high productionusing cheap raw materials such as oil waste, lactic whey and distillery waste. In spite of high demand, production is not competitive with those of chemical surfactant due to their high production costs and low yield, therefore, attempt has been made toincrease yield by using hyper producing mutants, optimizing media constituent and environmental condition. Factors which affect biosurfactants production are carbon sources, nitrogen sources, optimal pH, temperature, agitation and salt concentration.
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The effect of the H2S presence on the formation of six different sulphurated polycyclic hydrocarbons (S-PAH), during the pyrolysis of ethylene-H2S mixtures, has been studied in a tubular flow reactor installation. Experiments with...
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The effect of the H2S presence on the formation of six different sulphurated polycyclic hydrocarbons (S-PAH), during the pyrolysis of ethylene-H2S mixtures, has been studied in a tubular flow reactor installation. Experiments with different inlet H2S concentrations (0.3, 0.5 and 1%) and temperatures of reaction (between 1075 and 1475 K) have been carried out. The 16 compounds that the Environmental Protection Agency (EPA) has stated as EPA-PAH priority pollutants were also analysed. EPA-PAH compounds were the majority of quantified PAH, and also S-PAH were found and quantified. For temperatures studied, the S-PAH/EPA-PAH ratio values showed a maximum value at 1075 K and a minimum value at 1175 K. With respect to the effect of the inlet concentration of H2S, the S-PAH/EPA-PAH ratio values increased with the increase of the H2S concentration.
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The most common techniques for the analysis of PACs are GC and HPLC but they come with drawbacks: limited volatility for GC and insufficient resolution of complex samples with HPLC. Capillary electrophoresis (CE) has emerged in th...
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The most common techniques for the analysis of PACs are GC and HPLC but they come with drawbacks: limited volatility for GC and insufficient resolution of complex samples with HPLC. Capillary electrophoresis (CE) has emerged in the last decades as a method that can compete with chromatographic techniques for the analysis of PACs. The advantages are a high resolution and that separations are performed in the liquid phase so that volatility is not an issue. The critical issue is how to impart CE mobility to PACs. Interaction of the electrically neutral analytes with a charged carrier is inevitable and this review highlights such separations via interaction with monomelic and polymeric buffer additives. The separation of ionogenic PAHs and polycyclic aromatic heterocycles through protonation or deprotonation of the polar groups is also discussed.
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In the last years, there is great progress in the field of studies on the thermal transformation of wastes into valuable materials such as biochar. High-temperature processes, however, are connected with the formation of polycycli...
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In the last years, there is great progress in the field of studies on the thermal transformation of wastes into valuable materials such as biochar. High-temperature processes, however, are connected with the formation of polycyclic aromatic hydrocarbons (PAHs) with confirmed toxicity. However, during pyrolysis, some derivatives containing oxygen, nitrogen, or sulfur can also be formed. Their toxicity is expected to be higher than parent PAHs. However, the key parameter in the agricultural application of carbonaceous materials is PAHs' bioavailability. The aim of the presented studies was the determination of the effect of various feedstock (wheat straw (Triticum L.), willow (Salix viminalis), sunflower, residues from softwood and hardwood, sewage sludges, and residues from biogas production) on the formation of PAHs and their derivatives (0-, N-PAHs) in biochar and their bioavailability. The results indicated that the content of total and bioavailable PAHs in obtained biochar was rather low. The concentration of total PAHs in plant-derived biochar reached 57 ± 3 ng g~(-1) - 181 ± 8 ng g~(-1), whereas sewage sludge-derived biochar contained from 121 ± 6 ng g~(-1) to 188 ± 9 ng g~(-1) of PAHs. The highest concentration of PAHs was noted in biochar obtained from residues from biochar production - up to 202 ± 9 ng g~(-1). The total concentration of bioavailable PAHs was lower and reached 2-4.45 ng L~(-1) for plant-derived biochar, 3—40 ng L~(-1) for sewage sludge-derived biochar. The highest content of bioavailable PAHs was noted in biochar obtained from residues from biogas production: 9—42 ng L~(-1) indicating that increased attention should be paid to using this type of biochar. Among PAHs derivatives, nitronaphthalene, l-methyl-5-nitronaphthalene, l-methyl-6-nitronaphthalene, 9,10-anthracenedione, 4H-cyclopenta(def)phenanthrene, nitropyrene were determined at various levels and their concentrations were from below the limit of detection (LOD) to 28 ng L~(-1) for plant-derived biochar, 3-16 ng L~(-1) for biochar obtained from residues from biogas production, and 5-45 ng L~(-1) for sewage sludge-derived biochar. The content of bioavailable PAHs derivatives was, generally, one order of magnitude lower than parent PAHs derivatives, and reached from below LOD up to almost 1 ng IT1 for plant-derived biochar, from 0.5 to 2 ng L~(-1) for biochar obtained from residues from biogas production, and from 0.2 to almost 5 ng L~(-1) for sewage sludge-derived biochar confirming the safety of agricultural usage of biochar.
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Representative soil samples (n = 60) collected from suburban agricultural land in Tianjin were analyzed to determine 16 PAHs in this study. Accelerated solvent extraction, GPC (Gel Permeation Chromatography), and SPE (Solid Phase ...
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Representative soil samples (n = 60) collected from suburban agricultural land in Tianjin were analyzed to determine 16 PAHs in this study. Accelerated solvent extraction, GPC (Gel Permeation Chromatography), and SPE (Solid Phase Extraction) clean-up procedures were employed for PAH preparation prior to analysis with gas chromatography-mass spectrometry. The concentrations of the total PAHs (T-PAHs) ranged from 228.6ng/g to 14722.1ng/g with the mean value of 613.1ng/g. Bap concentrations in many sites exceeded the suggested standards. Spatial variation of PAHs in soil was illustrated; the pollution status and comparison to other cities were also investigated. Severe PAH soil pollution was observed in some sites near urban areas. Higher PAH concentrations were detected at the downwind side of the urban areas, indicating the influence of human activities. Two indicative ratios (Fl/(Fl+Pyr, Baa/(Baa+Chr)) and principal component analysis were used to identify the possible sources of PAHs. These suggested that coal combustion was still the most important source of PAHs in Tianjin, which coincided well with the previous studies. These data can be further used to assess the health risk associated with soils polluted by PAHs and can help local government find proper ways to reduce PAHs' pollution in soils.
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The results of monitoring of the persistent organic pollutant benzopyrene in soils of different functional areas of Moscow are presented. The highest concentrations of benzopyrene were found in the soils of the residential area an...
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The results of monitoring of the persistent organic pollutant benzopyrene in soils of different functional areas of Moscow are presented. The highest concentrations of benzopyrene were found in the soils of the residential area and near the MKAD. The coefficients of the pollutant concentrations were calculated (Kc), also the categorization of soils in terms of risk to the public were held.
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Representative agricultural soil samples from Tianjin, the third biggest city in China, were investigated for 16 PAHs in 2008 (n = 87) and 2012 (n = 60). Surface soil samples were air-dried and sieved. The total PAH (T-PAH) concen...
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Representative agricultural soil samples from Tianjin, the third biggest city in China, were investigated for 16 PAHs in 2008 (n = 87) and 2012 (n = 60). Surface soil samples were air-dried and sieved. The total PAH (T-PAH) concentrations ranged from 29.7 to 4502.5 ng/g (mean value 619.9 ng/g) in 2008; and from 228.6 to 14,722.1 ng/g (mean value 1295.8 ng/g) in 2012. Bap concentrations exceeded the suggested standards at many sites. Bap and T-PAH spatial variations were represented with maps. The pollution status was also compared to many other cities. PAH soil pollution near the urban areas was found to be serious in both 2008 and 2012. Pollution at some sites became severer in 2012 comparing to that in 2008. Principal component analysis and two indicative ratios were employed to find the potential sources. The results in the 2 years both revealed that the major source of soil PAHs was coal combustion, which coincided well with the previous studies. The study added to the basic data of local PAH distribution, and pointed out a proper way for the government to reduce the pollution.
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