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201.
While antimony has been reported to migrate from PET bottles into contents, reports on bottled water and soft drinks usage and PET bottle reuse patterns are currently unavailable in the literature. Bottle use conditions and patterns are important determinants of antimony migration. In this work a survey assessing the pattern of bottle use and reuse in Britain and Nigeria was undertaken. The survey findings influenced the design of laboratory experiments that assessed the migration of antimony from PET bottles into water and soft drinks. Typical storage durations for bottled contents between purchase and opening for use were 7 days or less. However storage of up to one year was reported. Bottle reuse was high and similar for the two countries with reuse durations being higher in Nigeria. The antimony concentration in 32 PET bottle materials from Britain and Nigeria were similar and ranged between 177 and 310 mg kg(-1). For 47 freshly purchased British bottled contents antimony concentration ranged between 0.03 and 6.61 μg L(-1) with only one sample exceeding the EU acceptable limit. Concentrations of Cd, Ge, Zn, Al, Be, Ti, Co and Pb were also measured. At realistic temperatures of 40 and 60 °C antimony concentration in deionised water in bottles remained below the EU acceptable limit even after 48 h exposure. The limit was exceeded for most exposures at 80 °C. Concentration of antimony in some bottled contents exceeded the EU limit after 11 months of storage at room temperature. Bottle aging and increase in bottle volume were associated with decreased migration of antimony from bottles.  相似文献   
202.
Sandy soil samples spiked with Bonny light crude oil were subsequently treated with Fenton's reagent at acidic, neutral, and basic pH ranges. Oil extracts from these samples including an untreated one were analyzed 1?week later with a gas chromatograph to provide evidence of hydrocarbon depletion by the oxidant. The reduction of three broad hydrocarbon groups-total petroleum hydrocarbon (TPH); benzene, toluene, ethylbenzene, and xylene (BTEX); and polycyclic aromatic hydrocarbon (PAH) were investigated at various pHs. Hydrocarbon removal was efficient, with treatment at the acidic pH giving the highest removal of about 96% for PAH, 99% for BTEX, and some TPH components experiencing complete disappearance. The four-ringed PAHs were depleted more than their three-ringed counterparts at the studied pH ranges.  相似文献   
203.
The distribution and concentrations of polychlorinated biphenyls (PCBs) were determined in fish species (European perch Perca fluviatilis, northern pike Esox lucius, pike perch Sander lucioperca, wels catfish Silirus glanus, common carp Cyprinus carpio, European eel Anguilla anguilla, freshwater bream Abramis brama, goldfish Carassius auratus, and roach Rutilus rutilus) in a heavily polluted water reservoir Zemplínska ?írava (Slovakia). The study performed at two different time points 5?years apart (2004 and 2009) revealed serious PCB contamination of fish muscle tissue and significant interspecies as well as tissue-specific differences in PCB uptake by fish. Total PCBs broadly correlated with the trophic position of individual fish species within a food chain (P??0.05). The study has shown that the kind of fish, its feeding habit, and specific conditions of the habitat are mutually interrelated factors that are responsible for significant variations in fish body burdens. A tendency to PCB biomagnification was also proved in some fish species of this water reservoir.  相似文献   
204.
Total suspended particle (TSP) collected at the fifth floor of House Dust in Hunan University, China, was analyzed in terms of microscopic morphology and chemical composition. The fine particles (50?nm-2?μm) in the TSP were analyzed by a high-resolution transmission electron microscope equipped with an energy-dispersive X-ray analyzer (HRTEM/EDS). Results showed that the particles were in shapes of plate, irregular and agglomerate. Based on EDS results, these fine particulate matter was primarily composed of Fe-rich (35.82-61.29%), Ca-rich (30.18-36.77%) and Si-rich (18.95-32.28%) particles. Other elements mainly including Mg (0.47-4.97%), Al (0.45-14.57%), S (0.45-4.73%), K (1.13-2.13%) and Zn (0.67-3.85%) were also observed. The sources analysis indicated that the HRTEM particles mainly originated from coal combustion, traffic emission, vehicles exhaust emission and fugitive soil or cement particulate matter. The coarse particles (4-50?μm) were detected by environmental scanning electron microscopy coupled with energy-dispersive X-ray detector (ESEM/EDS). Based on a simple algorithm, ESEM particles were categorized into five groups: C-bearing (46.15%, 67% and 86.98%), Si + Ca-bearing (21.48?+?11.80%, 16.51?+?10.81% and 16.32?+?10.62%), Si + Al-bearing (20.06?+?12.40%, 20.16?+?11.22% and 15.31?+?11.25%), Si-bearing (34.40%, 26.92% and 27.15%) particles and aggregates, most of which exhibit obvious crystalline structure, and these ESEM particles mainly derived from vehicles exhaust emission, coal combustion, soil, and biomass burning, while the aggregates are indicative of atmospheric reaction progress. HRTEM/EDS and ESEM/EDS are mutual complementary in analyzing the characteristic and determining the sources of TSP.  相似文献   
205.
In 1998, the Agrio and Guadiamar rivers underwent an enormous environmental disaster caused by the rupture of the Aznalcóllar tailings dam and the release of 6 hm3 of pyrite sludge and acidic water. Both rivers run over recent alluvial materials which form a small-sized aquifer which is however important because underground water feeds the flow of the rivers. This work analyzes the state of groundwater 10 years after the spill. Before the dam failure, this aquifer was already contaminated in the zone nearest to the mine, to which the impact of the spill was added. Contamination levels in the alluvial aquifer of the Agrio River have decreased remarkably. However, they are still important, with acidic pH values and high concentrations of toxic elements (maximum values of 16 mg/L of Zn and 15 mg/L of Al). There are also important levels of contamination in the Guadiamar alluvial area closest to the mine, as well as in specific zones located further south. The concentration of toxic elements is mainly controlled by pH. The evolution of contaminant levels show a sharp decrease after the first years following the spill, followed by a subsequent stabilization. It is necessary to take measures for the recovery of the aquifer because, otherwise, groundwater will continue contributing contaminants into the Agrio and Guadiamar rivers.  相似文献   
206.
Municipal solid waste incineration (MSWI) is a straightforward way to manage waste, however the disposal of process byproducts, mainly bottom and fly ash, is still a problem, because of their hazardous contents. Fly ash is a byproduct of many other processes that involve combustion to produce energy. In this paper we present and discuss a new method for MSWI fly ash inertization, mainly based on the use of colloidal silica as a stabilization agent for metals. In the patented procedure, fly ash of different provenance can be used to produce an inert and non-hazardous material, that can be reused. In fact to make the recovery process more efficient, landfilling should be totally avoided. For this reason, to enhance the possibility of reuse, a washing process, for salts recovery, is proposed as a final step of the inertization procedure. The obtained inert material is called COSMOS (COlloidal Silica Medium to Obtain Safe inert), and it is composed of calcium carbonate, calcium sulfate, silicon oxide and a wide quantity of non-soluble amorphous compounds. COSMOS does not contain any corrosive salts. This makes it extremely interesting for cement industry applications with several other advantages, and environmental benefits. The new proposed inertization procedure appears very promising, because it allows MSWI fly ash to be considered a valuable resource. Thanks to the obtained results, a demonstration project, in the frame of LIFE+, has been funded by the European Commission (LIFE+ 2008 project ENV/IT/000434, ).  相似文献   
207.
The concentrations of heavy metals and metals (Zn, Pb, Bi, Cd, Ni, Co, Fe, Mn, Mg, Cu, Cr, Ca, Sr, Na, Li, K) were measured in muscle of five species Cyprinus carpio (from I??kl? dam), Scardinius erythrophthalmus (from I??kl? dam), Tinca tinca (from I??kl? dam), C. carpio (from Karaca?ren dam), Carassius carassius (from Karaca?ren dam) caught from I??kl? and Karaca?ren. The highest metal was Na (466.95 μg/g) in C. carassius, while the lowest levels were Fe (0.37 μg/g) and Cu (0.37 μg/g) in C. carpio from I??kl? dam. The mean concentrations μg/g d.w. some of heavy metals in muscle of C. carpio (from I??kl? dam), S. erythrophthalmus (from I??kl? dam), T. tinca (from I??kl? dam), C. carpio (from Karaca?ren dam), C. carassius (from Karaca?ren dam) were as follows: Cd 2.00-2.10-1.95-2.06-2.27, Zn 4.36-2.64-13.13-13.33-24.47, Pb 1.65-1.24-1.90-2.37-2.41, Co 2.46-2.37-2.48-2.58-2.80, Mg 138.51-154.35-218.59-204.58-202.16, Fe 0.37-2.62-3.17-3.01-12.33, respectively.  相似文献   
208.
Jialing River is the largest tributary in the catchment area of Three Gorges Reservoir, and it is also one of the important areas of sediment yield in the upper reaches of the Yangtze River. In recent years, significant changes of water and sediment characteristics have taken place. The "Long Control" Project implemented since 1989 had greatly changed the surface appearance of the Jialing River Watershed (JRW), and it had made the environments of the watershed sediment yield and sediment transport change significantly. In this research, the Revised Universal Soil Loss Equation was selected and used to predict the annual average amount of soil erosion for the special water and sediment environments in the JRW after the implementation of the "Long Control" Project, and then the rainfall–runoff modulus and the time factor of governance were both considered as dynamic factors, the dynamic sediment transport model was built for soil erosion monitoring and forecasting based on the average sediment yield model. According to the dynamic model, the spatial and temporal distribution of soil erosion amount and sediment transport amount of the JRW from 1990 to 2007 was simulated using geographic information system (GIS) technology and space-grid algorithm. Simulation results showed that the average relative error of sediment transport was less than 10% except for the extreme hydrological year. The relationship between water and sediment from 1990 to 2007 showed that sediment interception effects of the soil and water conservation projects were obvious: the annual average sediment discharge reduced from 145.3 to 35 million tons, the decrement of sediment amount was about 111 million tons, and decreasing amplitude was 76%; the sediment concentration was also decreased from 2.01 to 0.578 kg/m3. These data are of great significance for the prediction and estimation of the future changing trends of sediment storage in the Three Gorges Reservoir and the particulate non-point source pollution load carried by sediment transport from watershed surface.  相似文献   
209.
A simple, sensitive and reliable HPLC-FLD method for the routine determination of 4-nonylphenol, 4-NP and 4-tert-octylphenol, 4-t-OP content in water samples was developed. The method consists in a liquid–liquid extraction of the target analytes with dichloromethane at pH  3.0–3.5 followed by the HPLC-FLD analysis of the organic extract using a Zorbax Eclipse XDB C8 column, isocratic elution with a mixed solvent acetonitrile/water 65:35, at a flow rate of 1.0 mL/min and applying a column temperature of 40°C. The method was validated and then applied with good results for the determination of 4-NP and 4-t-OP in Ialomi?a River water samples collected each month during 2006. The concentration levels of 4-NP and 4-t-OP vary between 0.08–0.17 μg/L with higher values of 0.24–0.37 μg/L in the summer months for 4-NP, and frequently <0.05 μg/L but also between 0.06–0.09 μg/L with higher values of 0.12–0.16 μg/L in July and August for 4-t-OP and were strongly influenced by sesonial and anthropic factors. The method was also applied on samples collected over 2 years 2007 and 2008 from urban wastewaters discharged into sewage or directly into the rivers by economic agents located in 30 Romanian towns. Good results were obtained when the method was used for analysis of effluents discharged into surface waters by 16 municipal wastewater treatment plants, during the year 2008.  相似文献   
210.
A total of 16 people died and over 500 people were hospitalized due to diarrhoeal illness in the Bholakpur area of Hyderabad, India on 6th May 2009. A study was conducted with immediate effect to evaluate the quality of municipal tap water of the Bholakpur locality. The study consists of the determination of physico-chemical properties, trace metals, heavy metals, rare earth elements and microbiological quality of drinking water. The data showed the variation of the investigated parameters in samples as follows: pH 7.14 to 8.72, EC 455 to 769 μS/cm, TDS 303.51 to 515.23 ppm and DO 1.01 to 6.83 mg/L which are within WHO guidelines for drinking water quality. The water samples were analyzed for 27 elements (Li, Be, B, Na, Mg, Al, Si, K, Ca, V, Cr, Mn, Fe, Ni, Co, Cu, Zn, As, Se, Rb, Sr, Mo, Ag, Cd, Sb, Ba and Pb) using inductively coupled plasma-mass spectrometry (ICP-MS). The concentrations of Fe (0.12 to 1.13 mg/L), Pb (0.01 to 0.07 mg/L), Cu (0.01 to 0.19 mg/L), Ni (0.01 to 0.15 mg/L), Al (0.16 to 0.49 mg/L), and Na (38.36 to 68.69 mg/L) were obtained, which exceed the permissible limits of the World Health Organization (WHO) for drinking water quality guidelines. The remaining elements were within the permissible limits. The microbiological quality of water was tested using standard plate count, membrane filtration technique, thermotolerant coliform (TTC), and most probable number (MPN) methods. The total heterotrophic bacteria ranged from 1.0 × 105 to 18 × 10cfu/ml. Total viable bacteria in all the water samples were found to be too numerable to count and total number of coliform bacteria in all water samples were found to be of order of 1,100 to >2,400 MPN index/100 ml. TTC tested positive for coliform bacteria at 44.2°C. All the water samples of the study area exceeded the permissible counts of WHO and that (zero and minimal counts) of the control site (National Geophysical Research Institute) water samples. Excessively high colony numbers indicate that the water is highly contaminated with microorganisms and is hazardous for drinking purposes. Bacteriological pollution of drinking water supplies caused diarrhoeal illness in Bholakpur, which is due to the infiltration of contaminated water (sewage) through cross connection, leakage points, and back siphoning.  相似文献   
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