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Widespread occurrence and seasonal variation of pharmaceuticals in surface waters and municipal wastewater treatment plants in central Finland 全文
2016
Lindholm-Lehto, Petra C. | Ahkola, Heidi S. J. | Knuutinen, Juha S. | Herve, Sirpa H.
The presence of five selected pharmaceuticals, consisting of four anti-inflammatory drugs, diclofenac, ibuprofen, ketoprofen, naproxen, and an antiepileptic drug carbamazepine, was determined at four municipal wastewater treatment plants (WWTPs) and in the receiving waterway in central Finland. The samples were taken from influents and effluents of the WWTPs and from surface water of six locations along the water way, including northern Lake Päijänne. In addition, seasonal variation in the area was determined by comparing the concentrations in the winter and summer. The samples were analyzed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) in the multiple reaction monitoring mode. The concentrations in the influents and effluents ranged from hundreds of nanogram per liter to microgram per liter while ranged from tens of nanogram per liter in northern parts of the waterway to hundreds of nanogram per liter in northern Lake Päijänne near the city area. In addition, the concentrations were higher in the winter compared to summer time in surface water due to decreased temperature and solar irradiation. On the other hand, higher concentrations of ibuprofen, ketoprofen, and naproxen were found in summer at the WWTPs, possibly due to seasonal variations in consumption. In conclusion, there are considerable amounts of pharmaceuticals not only in influents and effluents of the WWTPs but also in lake water along the waterway and in northern Lake Päijänne.
显示更多 [+] 显示较少 [-]Temporal and spatial variations in rotifer correlations with environmental factors in Shengjin Lake, China 全文
2016
Wang, Chao | Wang, Lan | Deng, Daogui | Zhou, Zhongze
Shengjin Lake is an important wintering and stopover habitat for migratory birds en route from East Asia to Australia. The authors investigated the rotifer community structure and environmental factors in upper Shengjin Lake from February to July of 2014. A total of 17 genera and 31 species of rotifers were identified, the dominant species being Brachionus angularis, Brachionus calyciflorus, Asplanchna priodonta, and Schizocerca diversicornis. Rotifer density and the nutrient salt content were higher in the areas inhabited by migratory birds. The highest density (176.0 ind./L) was recorded in June, the lowest (14.0 ind./L) in April. Canonical correspondence analysis (CCA) and correlation analysis showed that some environmental factors, such as temperature, pH, water depth, Secchi depth (SD), and chlorophyll a concentration, had a considerable effect on the lake’s rotifer community structure.
显示更多 [+] 显示较少 [-]Insights into the interaction between carbamazepine and natural dissolved organic matter in the Yangtze Estuary using fluorescence excitation–emission matrix spectra coupled with parallel factor analysis 全文
2016
Wang, Ying | Zhang, Manman | Fu, Jun | Li, Tingting | Wang, Jinggang | Fu, Yingyu
The interaction between carbamazepine (CBZ) and dissolved organic matter (DOM) from three zones (the nearshore, the river channel, and the coastal areas) in the Yangtze Estuary was investigated using fluorescence quenching titration combined with excitation emission matrix spectra and parallel factor analysis (PARAFAC). The complexation between CBZ and DOM was demonstrated by the increase in hydrogen bonding and the disappearance of the C=O stretch obtained from the Fourier transform infrared spectroscopy analysis. The results indicated that two protein-like substances (component 2 and component3) and two humic-like substances (component 1 and 4) were identified in the DOM from the Yangtze Estuary. The fluorescence quenching curves of each component with the addition of CBZ and the Ryan and Weber model calculation results both demonstrated that the different components exhibited different complexation activities with CBZ. The protein-like components had a stronger affinity with CBZ than did the humic-like substances. On the other hand, the autochthonous tyrosine-like C2 played an important role in the complexation with DOM from the river channel and coastal areas, while C3 influenced by anthropogenic activities showed an obvious effect in the nearshore area. DOMs from the river channel have the highest binding capacity for CBZ, which may ascribe to the relatively high phenol content group in the DOM.
显示更多 [+] 显示较少 [-]Early genotoxic response and accumulation induced by waterborne copper, lead, and arsenic in European seabass, Dicentrarchus labrax 全文
2016
Canalejo, Antonio | Diaz-de-Alba, Margarita | Granado-Castro, M Dolores | Córdoba, Francisco | Espada-Bellido, Estrella | Galindo-Riaño, M Dolores | Torronteras, Rafael
Early genotoxic response and accumulation induced by waterborne copper, lead, and arsenic in European seabass, Dicentrarchus labrax 全文
2016
Canalejo, Antonio | Diaz-de-Alba, Margarita | Granado-Castro, M Dolores | Córdoba, Francisco | Espada-Bellido, Estrella | Galindo-Riaño, M Dolores | Torronteras, Rafael
Cu, Pb, and As, which are among the most abundant metals in the aquatic environment, are also among the most health-threatened by causing diverse cellular injuries. The aim of this study was to assess and compare the potential early induction of genotoxic effects after waterborne Cu, Pb, and As exposure in European seabass, Dicentrarchus labrax, a commercial widely cultured fish, using the micronucleus (MN) assay in peripheral blood erythrocytes. Fish were exposed under laboratory conditions to nominal solutions ranging 0–10 mg/L for 24 and 96 h. Furthermore, actual metal ion concentrations were measured by inductively coupled plasma atomic emission spectroscopy (ICP-AES) or differential pulse anodic stripping voltammetry (DPASV) in water and four fish tissues differentially related to environmental exposition and metal accumulation, i.e. the gills, liver, muscle, and brain. Dose-dependent increases of micronuclei (MNi) frequency were observed after these very short exposures; based on measured metal concentrations in water, the genotoxic effect ordered as Cu > As > Pb. Significant genotoxic effect at 0.009 mg/L Cu, 0.57 mg/L Pb, and 0.01 mg/L As was seen. For Cu and Pb these are only slightly higher, but for As it is notably lower than the USEPA criteria of maximum concentration to prevent acute toxicity in aquatic organisms. Furthermore, genotoxicity was differentially related to metal accumulation. MNi frequency correlated positively with the content of Pb in all the organs, with the content of As in liver and gills and only with the content of Cu in the brain. In conclusion, our findings raised environmental concerns because these depicted a genotoxic potential of Cu, Pb, and As after a very short exposure to low but environmentally relevant concentrations, too close to regulatory thresholds. In addition, the MN test in D. labrax could be considered an early biomarker of genotoxicity induced by these metals in fish.
显示更多 [+] 显示较少 [-]Early genotoxic response and accumulation induced by waterborne copper, lead, and arsenic in European seabass, Dicentrarchus labrax 全文
2016
Canalejo, Antonio | Grandado-Castro, M. Dolores | Cordoba, Francisco | Torronteras, Rafael | Díaz de Alba, Margarita Isabel | Espada Bellido, Estrella | Galindo Riaño, María Dolores | Química Analítica
Cu, Pb, and As, which are among the most abundant metals in the aquatic environment, are also among the most health-threatened by causing diverse cellular injuries. The aim of this study was to assess and compare the potential early induction of genotoxic effects after waterborne Cu, Pb, and As exposure in European seabass, Dicentrarchus labrax, a commercial widely cultured fish, using the micronucleus (MN) assay in peripheral blood erythrocytes. Fish were exposed under laboratory conditions to nominal solutions ranging 0–10 mg/L for 24 and 96 h. Furthermore, actual metal ion concentrations were measured by inductively coupled plasma atomic emission spectroscopy (ICP-AES) or differential pulse anodic stripping voltammetry (DPASV) in water and four fish tissues differentially related to environmental exposition and metal accumulation, i.e. the gills, liver, muscle, and brain. Dose-dependent increases of micronuclei (MNi) frequency were observed after these very short exposures; based on measured metal concentrations in water, the genotoxic effect ordered as Cu>As>Pb. Significant genotoxic effect at 0.009 mg/L Cu, 0.57 mg/L Pb, and 0.01 mg/L As was seen. For Cu and Pb these are only slightly higher, but for As it is notably lower than the USEPA criteria of maximum concentration to prevent acute toxicity in aquatic organisms. Furthermore, genotoxicity was differentially related to metal accumulation. MNi frequency correlated positively with the content of Pb in all the organs, with the content of As in liver and gills and only with the content of Cu in the brain. In conclusion, our findings raised environmental concerns because these depicted a genotoxic potential of Cu, Pb, and As after a very short exposure to low but environmentally relevant concentrations, too close to regulatory thresholds. In addition, the MN test in D. labrax could be considered an early biomarker of genotoxicity induced by these metals in fish.
显示更多 [+] 显示较少 [-]Exploitation of subabul stem lignin as a matrix in controlled release agrochemical nanoformulations: a case study with herbicide diuron 全文
2016
Yearla, Srinivasa Rao | Padmasree, Kollipara
The utilization of nanomaterials in the domain of agriculture is at an inception, especially in the development of controlled release agrochemical nanoformulations. The present study demonstrated the potential of subabul stem lignin as a matrix material in agrochemical formulations using nanotechnology. In this study, “nanoprecipitation” method was employed and “optimized” to fabricate a stable herbicide, “diuron nanoformulation” (DNF). “Optimized DNF” (ODNF) has 5.17 ± 0.49 % diuron loading efficiency (DLE) and 74.3 ± 4 % encapsulation efficiency (EE). The size of nanoparticles in ODNF was 166 ± 68 nm as revealed by FESEM/TEM studies. Physicochemical characterization of ODNF by UV, FT-IR, and DSC studies revealed the successful loading of diuron within the lignin matrix. The ODNF exhibited nonlinear biphasic release profile for diuron. Further, the bioefficacy of diuron released from ODNF was tested using canola (Brassica rapa). B. rapa seedlings grown in the soil supplemented with ODNF showed early signs of leaf chlorosis and mortality when compared with seedlings grown in the presence of commercial diuron formulation (CDF) or bulk diuron (BD), respectively. This study not only revealed the exploitation of subabul stem lignin as a “matrix” in the controlled release nanoformulation of diuron but also opened up new avenues for utilizing it as matrix for several other agrochemicals associated with the growth and development of the plant.
显示更多 [+] 显示较少 [-]Effects of calcium supplementation on growth and biochemistry in two passerine species breeding in a Ca-poor and metal-polluted area 全文
2016
Espín, Silvia | Ruiz, Sandra | Sánchez-Virosta, Pablo | Eeva, Tapio
Several studies provide evidence of calcium (Ca)-limited reproduction in birds. A Ca-supplementation experiment was carried out in 2014 in a Ca-poor area associated with metal pollution in SW Finland. We aimed to evaluate the relationship between Ca availability and heavy metal exposure in free-living passerines, and to compare Ca levels in plasma and feces and the effects of Ca supplementation and metals on breeding, nestling growth, and plasma biochemistry in great tits and pied flycatchers. Although the Ca supplement was used by parents, in general the treatment had limited effects on growth and biochemistry, suggesting that parents are capable of finding sufficient Ca-rich foods to allow nestlings to grow properly. Snail shells were an abundant Ca source in the moderately polluted zone for pied flycatcher, and great tits likely combines the intake of snail shells and other anthropogenic Ca-rich items. Great tits had higher Ca concentrations in feces and plasma than pied flycatcher nestlings, suggesting that they need and sustain higher Ca levels and seem to be more opportunistic in search for Ca than pied flycatcher, since they consumed more of the supplemented Ca. Negative effects of pollution in nestling size and fledgling number were found in great tit. This species may suffer especially from the lower food quality and quantity in the polluted area. The pied flycatcher seems to be adapted to low Ca availability and they can successfully breed when metal concentrations are not too high. Our results show that great tits and pied flycatchers may employ different strategies in response to low Ca availability.
显示更多 [+] 显示较少 [-]Histopathological study of toxic effects of carbaryl on digestive tract of Bufotes variabilis (Anura: Bufonidae) 全文
2016
Çakıcı, Özlem
Due to the negative effects of pesticide usage in environment, i.e., decline in amphibian populations, this study was designed to examine histopathologic changes following carbaryl exposure for 96 h in the digestive tract of variable toad, Bufotes variabilis. After exposure to single doses of carbaryl (low dose 50 μg/g, medium dose 100 μg/g, and high dose: 200 μg/g), the toads were euthanized and dissected and digestive tract samples were quickly removed. Histopathology revealed esophageal vacuolization and necrosis in esophageal cells. Hemorrhage was also observed in the esophagus. In the stomach, necrosis in the glandular epithelium, congested blood vessels, edema among gastric glands, dilated tips of the mucosal epithelial layer, gastric glandular atrophy, and hemorrhage were found. In the intestine, edema within villi, hemorrhage, inflammation, vacuolization, and necrosis in epithelial cells of villi were detected. This study clearly showed that carbaryl caused adverse effects on the digestive tract of B. variabilis in all dose groups.
显示更多 [+] 显示较少 [-]In vitro quantitative determination of the concentration of the polymerization agent methyl 2-benzoylbenzoate in intravenous injection solution and the cytotoxic effects of the chemical on normal human peripheral blood mononuclear cells 全文
2016
Tsuboi, Chiaki | Kawasaki, Yoichi | Yoshitome, Kei | Yagi, Kenta | Miura, Taro | Esumi, Satoru | Miyazaki, Ikuko | Asanuma, Masato | Kitamura, Yoshihisa | Sendo, Toshiaki
In previous studies, we detected the photoinitiators 1-hydroxycyclohexyl phenyl ketone (1-HCHPK) and 2-methyl-4'-(methylthio)-2-morpholinopropiophenone (MTMP) in an intravenous injection solution. Importantly, 1-HCHPK and MTMP have been demonstrated to be cytotoxic to normal human peripheral blood (PB) mononuclear cells (MNC). Cell death (apoptosis) pathways can be classified into two modes, caspase-dependent and -independent pathways. However, it is unclear whether methyl 2-benzoylbenzoate (MBB) induces the caspase-dependent and/or -independent pathway in normal human PBMNC. In the present in vitro study, we examined the levels of MBB in a solution from an intravenous fluid bag and the cytotoxicity of MBB towards normal human PBMNC via the caspase-8-, caspase-9-, or apoptosis-inducing factor (AIF)-mediated apoptosis pathways. We found that extracts from the injection solution had been contaminated with approximately 80 μM of the photoinitiator MBB. In addition, MBB induced apoptosis in the high concentration range in normal human PBMNC in vitro. Moreover, we found that MBB-induced apoptosis occurs via the caspase-9 pathway, but not the AIF pathway. In conclusion, we suggest that MBB has cytotoxic effects on normal human PBMNC in vitro, which are mediated via the caspase-dependent pathway.
显示更多 [+] 显示较少 [-]A novel application of concentrated solar thermal energy in foundries 全文
2016
Selvaraj, J. | Harikesavan, V. | Eshwanth, A.
Scrap preheating in foundries is a technology that saves melting energy, leading to economic and environmental benefits. The proposed method in this paper utilizes solar thermal energy for preheating scrap, effected through a parabolic trough concentrator that focuses sunlight onto a receiver which carries the metallic scrap. Scraps of various thicknesses were placed on the receiver to study the heat absorption by them. Experimental results revealed the pattern with which heat is gained by the scrap, the efficiency of the process and how it is affected as the scrap gains heat. The inferences from them gave practical guidelines on handling scraps for best possible energy savings. Based on the experiments conducted, preheat of up to 160 °C and a maximum efficiency of 70 % and a minimum efficiency of 40 % could be achieved across the time elapsed and heat gained by the scrap. Calculations show that this technology has the potential to save around 8 % of the energy consumption in foundries. Cumulative benefits are very encouraging: 180.45 million kWh of energy savings and 203,905 t of carbon emissions cut per year across the globe. This research reveals immense scope for this technology to be adopted by foundries throughout the world.
显示更多 [+] 显示较少 [-]Catalyst support materials for prominent mineralization of bisphenol A in catalytic ozonation process 全文
2016
Cotman, Magda | Erjavec, Boštjan | Djinović, Petar | Pintar, Albin
Degradation of aqueous solution of bisphenol A (BPA) has been investigated through non-catalytic and catalytic ozonation treatments conducted in a semi-batch reactor. Non-catalytic ozonation resulted in complete degradation of aqueous BPA in less than 3 min but did not completely convert the reaction intermediates of BPA ozonation into CO₂ and H₂O. The main goal of this study was to find an effective heterogeneous catalyst to increase the extent of BPA mineralization at different pH conditions. In this way, the most promising catalyst carrier was γ-Al₂O₃; at pH = 8.0, 68 % of total organic carbon (TOC) was removed in the period of 75 min, out of which 42 % was attributed to mineralization. Finally, 3.0 wt.% Ru/γ-Al₂O₃ catalyst exhibited over 82 % of TOC removal after 240 min of ozonation at pH = 5.9, of which 56 % was mineralized.
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