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931.
Source to sink tracking of selected human pharmaceuticals from two Oslo city hospitals and a wastewater treatment works 总被引:4,自引:0,他引:4
Thomas KV Dye C Schlabach M Langford KH 《Journal of environmental monitoring : JEM》2007,9(12):1410-1418
The occurrence of twenty pharmaceutical compounds was quantitatively determined in effluents from two major Oslo city hospitals, Rikshospitalet and Ullev?l, along with influent, sludge and final effluent from the city's VEAS wastewater treatment works (WTW). Composite hospital effluents were collected over a twelve week period and were showed to contain paracetamol, metoprolol, diclofenac, ibuprofen, 17beta-Estradiol, estriol, estrone, oxytetracycline, tetracycline, doxycycline, chlorotetracycline, demeclocycline, trimethoprim, ciprofloxacin, sulfamethoxazole, cyclophosphamide and ifosfamide. Three pharmaceuticals were not detected above the limit of detection; cefuroxime, 17alpha-ethinylestradiol and meclocycline. Composite influent, sludge and effluent samples were collected from VEAS WTW over a seven week period. The influent into VEAS WTW contained all of the same selected substances detected in the hospital effluents, except for oxytetracycline, chlorotetracycline, demeclocycline, cyclophosphamide and ifosfamide. The percentage of pharmaceuticals entering the works from the hospitals was <10% for all of the selected compounds. VEAS sludge samples contained a different profile of substances reflecting their physico-chemical properties. Hydrophobic antibiotics, such as oxytetracycline, tetracycline and ciprofloxacin, were detected in all of the collected sludge samples. Their absence in the collected influent samples suggests that they enter the works bound to effluent particles, with the dissolved fraction observed in the hospital effluents partitioning onto particulate matter within the sewerage network. The final effluent from VEAS WTW contained reduced concentrations of many pharmaceuticals, including paracetamol, ibuprofen and sulfamethoxazole. For other compounds, such as metoprolol, diclofenac and trimethoprim, there were often higher concentrations in the effluent than the influent. These effluent concentrations represent median inputs varying from low g day(-1) (e.g. paracetamol and ibuprofen) to nearly 200 g day(-1) (e.g. metoprolol and trimethoprim) into Oslofjord. A simple risk assessment showed that the antibiotic ciprofloxacin may at times pose an acute risk to the Oslofjord aquatic environment. 相似文献
932.
Elimination of alkylphenol ethoxylates (APEO) and their degradation products (alkylphenols and alkylphenoxy carboxylates), as well as linear alkylbenzene sulfonates (LAS) and coconut diethanol amides (CDEA), was studied in a pilot plant membrane bioreactor (MBR) working in parallel to a full-scale wastewater treatment plant (WWTP) using conventional activated sludge (CAS). In the CAS system 87% of parent long ethoxy chain NPEOs were eliminated, but their decomposition yielded persistent acidic and neutral metabolites which were poorly removed. The elimination of short ethoxy chain NPEOs (NP(1)EO and NP(2)EO) averaged 50%, whereas nonylphenoxy carboxylates (NPECs) showed an increase in concentrations with respect to the ones measured in influent samples. Nonylphenol (NP) was the only nonylphenolic compound efficiently removed (96%) in the CAS treatment. On the other hand, MBR showed good performance in removing nonylphenolic compounds with an overall elimination of 94% for the total pool of NPEO derived compounds (in comparison of 54%-overall elimination in the CAS). The elimination of individual compounds in the MBR was as follows: 97% for parent, long ethoxy chain NPEOs, 90% for short ethoxy chain NPEOs, 73% for NPECs, and 96% for NP. Consequently, the residual concentrations were in the low mug/l level or below it. LAS and CDEA showed similar elimination in the both wastewater treatment systems that were investigated, and no significant differences were observed between the two treatment processes. Nevertheless, for all studied compounds the MBR effluent concentrations were consistently lower and independent of the influent concentrations. Additionally, MBR effluent quality in terms of chemical oxygen demand (COD), NH(4)(+) concentration and total suspended solids (TSS) was always superior to the ones of the CAS and also independent of the influent quality, which demonstrates high potential of MBRs in the treatment of municipal wastewaters. 相似文献
933.
Dwivedi S Tripathi RD Srivastava S Mishra S Shukla MK Tiwari KK Singh R Rai UN 《Chemosphere》2007,67(1):140-151
The disposal of fly-ash (FA) from coal-fired power stations causes significant economic and environmental problems. Use of such contaminated sites for crop production and use of contaminated water for irrigation not only decreases crop productivity but also poses health hazards to humans due to accumulation of toxic metals in edible grains. In the present investigation, three rice cultivars viz., Saryu-52, Sabha-5204, and Pant-4 were grown in garden soil (GS, control) and various amendments (10%, 25%, 50%, 75% and 100%) of FA for a period of 90 days and effect on growth and productivity of plant was evaluated vis-a-vis metal accumulation in the plants. The toxicity of FA at higher concentration (50%) was reflected by the reduction in photosynthetic pigments, protein and growth parameters viz., plant height, root biomass, number of tillers, grain and straw weight. However, at lower concentrations (10-25%), FA enhanced growth of the plants as evident by the increase of studied growth parameters. The cysteine and non-protein thiol (NP-SH) content showed increase in their levels up to 100% FA as compared to control, however, maximum content was found at 25% FA in Saryu-52 and Pant-4 and at 50% FA in Sabha-5204. Accumulation of Fe, Si, Cu, Zn, Mn, Ni, Cd and As was investigated in roots, leaves and seeds of the plants. Fe accumulation was maximum in all the parts of plant followed by Si and both showed more translocation to leaves while Mn, Zn, Cu, Ni and Cd showed lower accumulation and most of the metal was confined to roots in all the three cultivars. As was accumulated only in leaves and was not found to be in detectable levels in roots and seeds. The metal accumulation order in three rice cultivars was Fe > Si > Mn > Zn > Ni > Cu > Cd > As in all the plant parts. The results showed that rice varieties Saryu-52 and Sabha-5204 were more tolerant and could show improved growth and yield in lower FA application doses as compared to Pant-4. Thus, Sabha-5204 and Saryu-52 are found suitable for cultivation in FA amended agricultural soils for better crop yields. 相似文献
934.
HPLC-DAD, HPLC-MS/MS, GC-MS and spectrophotometric methods are employed to investigate the degradation process of sodium 1-amino-5-naphthalene sulfonate (1A5NS) aqueous solutions, when exposed to sunlight and UV-lamp (254 nm) irradiations. Experimental results show that both sunlight and 254 nm UV-lamp irradiations destroy the chemical and give rise to major degradation products, characterised by the same m/z ratios. Degradation times are lower for sunlight irradiation, for which a t(1/2) value of 137.4 min has been evaluated, in comparison with the value of t(1/2) of 26.8 min, observed for UV-lamp irradiation. The degradation pathway and the structures of the degradation products are proposed. 相似文献
935.
Two alternative, cost- and time-effective dioxin screening methods relying on two categories of potential lipid biomarkers were investigated. A dioxin range varying from 1.1 to 47.1 pg PCDD/F TEQ-WHO/g lipid using 64 fish meal samples was used for model calibration. The methods were based on multivariate models using either (1) fatty acid composition monitored by GC-FID or (2) fluorescence landscape signals analysed using the PARAFAC model and in both cases predicting dioxin content as pgPCDD/F TEQ-WHO/g lipid. In both cases, Partial Least Squares (PLS) regression was performed for predicting the dioxin content of a sample. The GC-FID data analyses was based on automatic peak alignment and integration, enabling extraction of the area of 140 peaks from the gas chromatograms, as opposed to the 31 fatty acids usually considered for fish oil characterisation. In addition to classic PLS employing the whole dataset for calibration, a two-step local PLS modeling approach was performed based upon an initial selection of k number of calibration samples providing the best match to the prediction sample using a so-called k Nearest Neighbors (kNN) approach, then followed by PLS calibration on these kNN selected samples for dioxin prediction. Fluorescence spectroscopy offers a promising non-invasive and ultra-rapid technique, with less than two minutes analysis time. However, fluorescence spectroscopy using the pattern recognition "kNN-PLS" yielded a correlation of 0.76 (r2) and a high root mean square error of prediction of 11.4 pg PCDD/F TEQ-WHO/g lipid. The predictions were improved when the PLS calibration was performed on all the sample with a root mean square error of prediction of 7.0 pg PCDD/F TEQ-WHO/g lipid. Unfortunately, these results failed to demonstrate the potential of fluorophore monitoring as a screening method. In contrast, the overall best screening performance was obtained with the fatty acid profile, when the kNN-PLS combination employed for pattern recognition (kNN) all the areas of the 140 detected peaks and the PLS regression used the areas of 46 selected peaks. This "kNN-PLS" prediction with three latent variables and based upon the 12 nearest neighbors selected out of the 64 x 2 fatty acid profiles (duplicate analyses), yielded a correlation of 0.85 (r2) and a root mean square error of prediction of 2.1 pg PCDD/F TEQ-WHO/g lipid and resulted in a total analysis time of one and half hour per sample. 相似文献
936.
Specimens of farmed European sea bass (Dicentrarchus labrax L., 1758) were exposed to different cadmium (Cd) concentrations (4.47, 5.63, 7.08 and 8.91 mg l(-1)) for 24 and 48 h. The effects of Cd on numbers of some cell types and structures (i.e., chloride cells, CCs; macrophage aggregates, MAs; rodlet cells, RCs) and on structure and ultrastructure of the main organs (gill, liver, intestine, kidney) were studied with routine process for light and transmission electron microscopy. Following cadmium exposure, the numbers of branchial CCs as well as intestinal and renal RCs increased significantly within 24h. Increase in metal concentration did not affect the magnitude of the numerical increment of the aforementioned cells. Moreover, in treated fish (24 and 48 h) the numbers of MAs in both head kidney and spleen were significantly higher than in control conspecifics, whilst the global area of MAs was less influenced by the acute treatment. In exposed sea bass, all the examined organs exhibited cellular modifications which appeared time- and dose-dependent. The gills showed telangectasia, lamellar fusion, oedema, epithelial lifting and leukocyte infiltration. In the liver, kidney and intestine acute cell swelling and vacuolization were common. Ultrastructurally the alterations observed frequently in hepatocytes, tubular epithelial cells and enterocytes included presence of numerous myelinoid bodies, damaged mitochondria, dilatation of endoplasmic reticulum, high number of lysosomes and autophagolysosomes. In intestinal and kidney tubular epithelia of treated fish, rodlet cells displayed some anomalies like dilatation of nuclear envelope, cytoplasmic vacuolization, presence of myelinoid bodies, rodlets degeneration and extensive discharge activity. 相似文献
937.
In this work, the treatment of an actual industrial waste with three advanced oxidation processes (AOP) has been studied: conductive-diamond electrooxidation (CDEO), ozonation and Fenton oxidation. The wastewater comes from olive-oil mills (OMW) and contains a COD of nearly 3000 mg dm(-3). CDEO allowed achieving the complete mineralization of the waste with high current efficiencies. Likewise, both ozonation and Fenton oxidation were able to treat the wastes, but they obtained very different results in terms of efficiency and mineralization. The accumulation of oxidation-refractory compounds as final products excludes the use of ozonation and Fenton oxidation as a sole treatment technology. This confirms that besides the hydroxyl-radical mediated oxidation, CDEO combines other important oxidation processes such as the direct electro-oxidation on the diamond surface and the oxidation mediated by other electrochemically formed compounds generated on this electrode. 相似文献
938.
The use of maize and poplar in chelant-enhanced phytoextraction of lead from contaminated agricultural soils 总被引:3,自引:0,他引:3
Chelant-enhanced phytoextraction of heavy metals is an emerging technological approach for a non-destructive remediation of contaminated soils. The main objectives of this study were (i) to assess the extraction efficiency of two different synthetic chelating agents (ethylenediaminetetraacetic acid (EDTA) and ethylenediaminedisuccinic acid (EDDS)) for desorbing Pb from two contaminated agricultural soils originating from a mining and smelting district and (ii) to assess the phytoextraction efficiency of maize (Zea mays) and poplar (Populus sp.) after EDTA application. EDTA was more efficient than EDDS in desorbing and complexing Pb from both soils, removing as much as 60% of Pb. Maize exhibited better results than poplar when extracting Pb from the more acidic (pH approximately 4) and more contaminated (up to 1360 mg Pb kg(-1)) agricultural soil originating from the smelting area. On the other hand, poplars proved to be more efficient when grown on the near-neutral (pH approximately 6) and less contaminated (up to 200 mg Pb kg(-1)) agricultural soil originating from the mining area. Furthermore, the addition of EDTA led to a significant increase of Pb content especially in poplar leaves, proving a strong translocation rate within the poplar plants. 相似文献
939.
Adamo P Crisafulli P Giordano S Minganti V Modenesi P Monaci F Pittao E Tretiach M Bargagli R 《Environmental pollution (Barking, Essex : 1987)》2007,146(2):392-399
Lobes of the lichen Pseudevernia furfuracea (L.) Zopf and shoots of the moss Hypnum cupressiforme Hedw. were subjected to different treatments (water washing, oven drying, HNO3 washing, NH4-oxalate extraction) to assess the influence of vitality on accumulation efficiency, during a 6-week exposure in bags in two Italian cities, Trieste and Naples. No trend emerged between treatments, in terms of accumulation ability, for major and trace elements. Only water-washed lichens showed an increased C and N content after exposure in both cities. Element concentrations generally reached higher values in mosses than in lichens, especially for Al, Fe, and Zn (both cities), and for Cu, Mg and Na (Naples). Surface development strongly influenced accumulation capacity of the biomonitors. Quartzose and cation exchange filters revealed, on a weight basis, a poor performance. In urban environments, surface interception of atmospheric particulate seems to play a major role in accumulation, irrespective of organism vitality. 相似文献
940.
Martínez-Carballo E Sitka A González-Barreiro C Kreuzinger N Fürhacker M Scharf S Gans O 《Environmental pollution (Barking, Essex : 1987)》2007,145(2):489-496
A method for simultaneous quantitative determination of alkyl benzyl, dialkyl and trialkyl quaternary ammonium compounds (QACs) has been developed, validated and subsequently applied to real water samples in Austria. The method employs liquid-liquid extraction (LLE) followed by liquid chromatography/tandem mass spectrometry (LC-MS/MS), using electrospray ionization (ESI) in positive mode. The overall method quantification limits range from 4 to 19ng/L for the enrichment of 500mL water samples and analyte recoveries are between 80 and 99%. The method was applied to 62 of the respective water samples without filtration to avoid the loss of the analytes due to the high adsorption capacity of these compounds. Maxima in the mg/L range, especially in the wastewater of hospitals and laundries, could be detected for the selected target compounds. 相似文献