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Contado C Blo G Conato C Dondi F Beckett R 《Journal of environmental monitoring : JEM》2003,5(6):845-851
A review of the different methodologies employed to fractionate and characterize riverine suspended particulate matter is presented. The importance of size-based metal speciation is underlined and the possibility of studying it by the Sedimentation Field Flow Fractionation (SdFFF) technique is illustrated. The studies on the metal load in river Suspended Particulate Matter (SPM) performed over the last ten years are critically reviewed focusing on the different methods employed to collect, concentrate and size-fractionate samples. The fact that there is no homogeneity in methods and data collection in this field is underlined. Among the different fractionation techniques, Field Flow Fractionation (FFF) methodologies have proved to be a good approach to study the role of SPM in metal load and transport. The possibility of studying size-based metal speciation using the SdFFF technique is presented and the importance of metal speciation in rivers is underlined. 相似文献
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Bohari Y Lobos G Pinochet H Pannier F Astruc A Potin-Gautier M 《Journal of environmental monitoring : JEM》2002,4(4):596-602
A recently developed method for the determination of arsenic species (arsenite, arsenate, monomethylarsonate, MMAA, and dimethylarsinate, DMAA) has been applied to the study of arsenic speciation in plants. This method uses ion-exchange liquid chromatography coupled on-line to atomic fluorescence spectrometry through continuous hydride generation. Various extraction procedures have been studied in detail using three plant certified reference materials. None of the procedures tested revealed fully satisfying results with all kinds of plant samples; microwave assisted extraction with 0.3 mol dm-3 orthophosphoric acid was found to be the most convenient for dealing with terrestrial plants. Species stability appears good. This method was applied to real world cultivated plant parts. Arsenate appears to predominate in soils, roots and leaves; unidentified species (probably arsenosugars) play an important role (60%) in rice fruits. Carrot was found to be the most contaminated edible plant part, containing 1 mg kg-1 essentially as arsenate species. MMAA was detected in all soils and some plant parts especially shallots at low levels, whereas DMAA was found only in one soil sample and in hot pepper leaves. Arsenite is a minor component of all soils; it is also present in some plant parts at low levels. However, no evident relationships were found between As speciation in the various plant parts and much more detailed studies will be necessary to elucidate As behaviour in plants. 相似文献
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Pharmaceuticals are bioactive compounds generally resistant to biodegradation, which can make them problematic when they are released into nature. The use pattern for pharmaceuticals means that they are discharged into water via sewage treatment plants. Also surfactants are discharged through sewage treatment plants, primarily due to their use in detergents and shampoos and other cleaners. In this study the acute toxicity to Daphnia magna of four pharmaceuticals (ciprofloxacin, ibuprofen, paracetamol and zinc pyrithione) and seven surfactants (C8 alkyl glucoside, C6 alkyl glucoside, sodium caprylimidiopropionate, tallow-trimethyl-ammonium chloride, potassium decylphosphate, propylheptanol ethoxylate and alkylmonoethanolamide ethoxylate) was determined. Abiotic (without activated sludge bacteria) and biotic (with activated sludge bacteria) detoxification was also determined. The 24-h EC50s ranged from 2 μg L(-1) for the most toxic substance (zinc pyrithione) to 2 g L(-1) for the least toxic compound (C6 alkyl glucoside). Detoxification rates determined as the ratio between initial EC50 and EC50 after 1 week in water with activated sludge bacteria ranged from 0.4 (paracetamol) to 13 (zinc pyrithione). For most of these chemicals detoxification rate decreased after 1 week, but for one (alkylmonoethanolamide ethoxylate) it increased from about 2 to 30 times after 2 weeks. Many of these chemicals were "detoxified" also abiotically at about the same rate as biotically. Further studies are needed to determine the degradation products that were precipitated (aggregated) for some of the tested chemicals. Altogether, this study has shown that there are large differences in toxicity among chemicals entering sewage treatment plants, but also that the detoxification of them can differ. Therefore, the detoxification should receive more attention in the hazard and risk assessment of chemicals entering sewage treatment plants. 相似文献
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Persi Elisabetta Petaccia Gabriella Sibilla Stefano Lucía Ana Andreoli Andrea Comiti Francesco 《Environmental Fluid Mechanics》2020,20(3):539-558
Environmental Fluid Mechanics - The Eulerian–Lagrangian model ORSA2D_WT is employed for the simulation of uncongested wood transport, with reference to a field experiment that studied the... 相似文献
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Rita Galántai Blanka Emődy-Kiss Zoltán Somosy Gabriella Bognár Győző Horváth Zsolt Forgács 《Journal of environmental science and health. Part. B》2013,48(8):773-779
This investigation was undertaken to elucidate whether the active metabolite of malathion, malaoxon, has any role in exerting cyto- and genotoxic effects for human choriocarcinoma (JAR) cell line which is an acceptable model for human placental cells. Gas chromatography-mass spectrometry (GC-MS) analysis were separately performed on the cell compartment and supernatant cell culture medium after subjecting the cell line to different malathion concentrations (10–400 μg/mL) and for various incubation periods (0.5 to 24 hours). GC-MS analysis showed that the sonication performed for the disruption of the cells did not cause the chemical change of malathion. The uptake of malathion by the cells was relatively fast. However, the presence of malaoxon, even in trace amounts, could not be confirmed either in samples originating from disrupted cells or in the cell culture medium. Although the hydrolysis of malaoxon occurred in the culture medium, this degradation process could not be counted as a reason for the absence of malaoxon. Since both malathion and malaoxon standard compounds could be accurately detected and distinguished by the applied liquid-liquid extraction and GC-MS methods, one can conclude that, in the case of JAR cells, the parent compound, (i.e. malathion itself) is responsible for the observed in vitro cyto- and genotoxic effects. Our results indicate that the direct toxicity of malathion contributes to the complications of pregnancy observed for environmental malathion exposure. 相似文献
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Serracca Laura Rossini Irene Battistini Roberta Goria Maria Sant Serena De Montis Gabriella Ercolini Carlo 《Food and environmental virology》2012,4(3):89-92
In this study, we investigated the presence of enteric viruses such as norovirus (NoV), hepatitis A virus (HAV), hepatitis E virus (HEV), and adenovirus (HAdV), in vegetables available on the Italian markets. For this aim, 110 national and international ??ready to eat?? samples were collected and analyzed by biomolecular tests and positive samples were confirmed by sequencing. All samples (100?%) were negative for HAV, HEV, and HAdV, while 13.6?% (15/110) were positive for NoV. Actually there is not a formal surveillance system for NoV infections in Italy but we clearly demonstrated a potential risk associated with the consumption of ??ready to eat?? vegetables. This study confirmed for the first time in Italy the presence of norovirus in semi-dried tomatoes by PCR technique. 相似文献
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Angelo Canale Salvatore Giacinto Germinara Adriano Carpita Giovanni Benelli Gabriella Bonsignori Cesare Stefanini Alfio Raspi Giuseppe Rotundo 《Chemoecology》2013,23(3):155-164
In the olive fruit fly, Bactrocera oleae, females attract males by producing 1,7-dioxaspiro[5.5]undecane (olean), the main component of the sex pheromone secreted by rectal glands. It has been recently demonstrated that males are able to produce (Z)-9-tricosene (muscalure) in rectal glands, a compound that selectively attracts females. In this study, a male grooming reaction that may transfer the male-borne compounds from rectal to urotergal glands was observed, suggesting that urotergal glands could be involved in B. oleae sexual communication. GC/MS, EAG, GC/EAD analyses and behavioural assays were carried out to compare the role of male rectal and urotergal glands during courtship. In both male glands, olean and muscalure amounts were age dependent. Extracts of rectal glands contained higher amounts of olean and/or muscalure than urotergal ones. Extracts of rectal and urotergal glands of males and females elicited EAG responses in both sexes. GC/EAD showed that female EAG response to male rectal extracts was mainly due to olean and muscalure. Synthetic compounds evoked EAG dose-dependent responses in both sexes, and the EAG response to muscalure was higher as compared to olean. Rectal and urotergal glands from old males were able to attract females, while urotergal glands from young males attracted only males. Overall, our results add knowledge to the mating system of B. oleae, giving first evidences on the electrophysiological activity of muscalure towards both sexes, as well as on the involvement of male urotergal glands in the chemical sexual communication of this pest. 相似文献