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1.
Examination of the Degradation of Drugs in Municipal Sewage Plants Using Liquid Chromatography-Electrospray Mass Spectrometry Numerous drugs can be identified in the secondary effluent of municipal sewage plants. In order to obtain information about the degree of elimination (adsorption, aerobic degradation) of these compounds, a batch reactor containing different drugs in environmentally relevant concentrations and a suspension of activated sludge was coupled to a HPLC-MS-MS system. During a testing period of three days concentration-time-curves were recorded. For most of the examined drugs (acetamidoantipyrine, crotamiton, diclofenac, primidone, propyphenazone) solely a strong decrease of the initial concentration within the first 15 minutes was observed, which was interpreted primarily as adsorption to the activated sludge. For acetaminophenol and pentoxifyllin an additional slower decrease in concentration within several hours was observed. This slower elimination was interpreted to be caused mainly by primary degradation. It could be shown that dihydrocodeine is oxidized to hydrocodone in the batch reactor. The conjugate acetaminophen glucuronide was cleaved. 相似文献
2.
Polycyclic musks and nitro musks were found as environmental pollutants in screening analyses of 30 representative surface water samples collected from rivers, lakes, and canals in Berlin. These synthetic musks, which are used as fragrances in cosmetics, detergents, and other products, are discharged by the municipal sewage treatment plants into Berlinπs surface waters. In particular, the polycyclic musks 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta-(g)-2-benzopyrane (HHCB; Galaxolide®, Abbalide®) and 7-acetyl-1,1,3,4,4,6-hexamethyltetraline (AHTN; Tonalide®, Fixolide®) were found in the receiving surface waters at considerable concentrations up to the μg/L-level. In the Wuhle, a small brook almost totally consisting of sewage effluents, maximum concentrations were 12.5 μg/L for HHCB and 6.8 μg/L for AHTN. Additionally, the polycyclic musk 4-acetyl-1,1-dimethyl-6-tert-butylindane (ADBI; Celestolide®, Crysolide®) and 1-tert-butyl-3,5-dimethyl-2,6-dinitro-4-acetylbenzene (musk ketone) were detected at low concentrations in most of the samples. Two other nitro musks, namely 1,1,3,3,5-pentamethyl-4,6-dinitroindene (musk moskene) and 1-tert-butyl-3,5-dimethyl-2,4,6-trinitrobenzene (musk xylene), were only detected in a single surface water sample. Solid-phase microextraction (SPME) with detection by gas chromatography-mass spectrometry (GC-MS) has proven to be a rapid and reliable tool for the screening of synthetic musks in surface and sewage water samples. Internal calibration with a suitable internal standard enables reproducible quantitation of the analytes down to the low ng/L-level. 相似文献
3.
In a surface water screening, 30 representative surface water samples collected from rivers, canals, and lakes in Berlin were investigated for the presence of 22 substituted phenols. The phenols selected include the 11 phenols considered as “priority pollutants” by the US Environmental Protection Agency (US-EPA). Surface water samples were extracted applying solid-phase extraction with styrenedivinylbenzene adsorbent. The recoveries, determined in spiking experiments, were between 80 % and 103 %. After derivatization with N-(tert-butyldimethylsilyl)-N-methyl-trifluoroacetamide (MTBSTFA) the samples were analyzed by capillary gas chromatography-mass spectrometry (GC-MS). Phenol, cresols, 2-ethylphenol, 2-chlorophenol, 4-chloro-3-methylphenol, pentachlorophenol, 2-nitrophenol, and 4-nitrophenol were detected in the surface water samples at concentrations between 0.02 μg/L and 7.8 μg/L, respectively. The distribution of these residues in the Berlin surface waters showed that the phenolic residues, with the exception of pentachlorophenol and 2-ethylphenol, do not originate primarily from municipal sewage treatment plants discharges. Some of the phenols are formed naturally or occur as ubiquitous anthropogenic contaminants in the aquatic system. 相似文献
4.
The roles of oxygen and its activated species (superoxide radicals, hydrogen peroxide, hydroxyl radicals), as well as that of sulfur compounds, are considered in relation to biological quality and the self-cleaning capacity of freshwater aquatic systems. The effects on the aquatic redox-processes are discussed in terms of atmospheric fallout of sulfur compounds, bottom sediment composition, and input of wastewaters containing reducing substances. It is shown that the totality of anthropogenic influences, and/or unfavourable natural geochemical conditions, as well as climatic effects in a region can increase the significance of one-electron transfer processes in bio-geochemical cycles of oxygen, sulfur and manganese, compared with the significance of two-electron transfer processes. The resulting, reactive intermediate products of one-electron transfer processes are very important with respect to the composition and properties of aquatic systems. Examples are given of practical applications of wastewater treatment, using hydrogen peroxide and UV-irradiation, and of regulation of consumers’ activities which affect natural waters. 相似文献
5.
John P. Sumpter 《洁净——土壤、空气、水》2005,33(1):9-16
Although a relatively new area of environmental research, the field of endocrine disruption has grown very rapidly, and currently many hundreds, perhaps even a few thousand, papers are published annually on the many different aspects covered by the field. As far as endocrine disruption in wildlife is concerned, most attention has been focused on aquatic organisms, for two reasons. Firstly, the aquatic environment receives most of the pollutants intentionally released into the environment, through effluents from wastewater treatment plants, and secondly because many of the best documented examples of endocrine disruption in wildlife are of partially or completely aquatic species. These two reasons are probably not unconnected, of course. Hence, aquatic organisms can receive continuous exposure to endocrine‐disrupting chemicals throughout their lives, albeit usually to low concentrations of these chemicals. Analysis of effluents has identified many of the endocrine‐disrupting chemicals present, and shown that these are both natural and man‐made, and vary greatly in potency. Most attention has been directed to identifying the main estrogenic chemicals, because many of the effects reported in wildlife appear to be a consequence of ‘feminization’ of males. However, chemical analysis of effluents has also demonstrated that chemicals with other types of endocrine activity are present, such as androgens, anti‐androgens, progestagens, etc. The effects (if any, of course) of such chemicals on aquatic organisms are unknown, and largely uninvestigated, presently. Much of the biological research has centred on the effects of estrogenic chemicals, especially to fish. These effects, such as elevated vitellogenin concentrations and intersexuality, have to date been studied almost exclusively at the level of the individual, and hence whether endocrine‐disrupting chemicals cause population‐level consequences is largely unknown (the undeniable effects of TBT on molluscs, leading to local extinctions, being the exception). It is my opinion that rather too much of the recent research has not advanced our understanding of endocrine disruption a great deal, and we are probably not much further forward now than we were five years or so ago. It is surely time to tackle some of the outstanding, unresolved issues, such as the impact of endocrine disruption at the population level, and the issue of how organisms respond when exposed to complex mixtures of endocrine active chemicals. Such research will not be easy, and will require multidisciplinary teams, including people with expertise in areas not yet involved in the field of endocrine disruption, such as mathematical modellers. However, until such research is done, it will not be possible to decide how important an issue endocrine disruption is to wildlife, and how that importance compares to the other factors adversely affecting wildlife, such as habitat loss, climate change, and the introduction of exotic species and novel diseases. 相似文献
6.
The separation of heavy metals from wastewater may be improved by precipitation/flocculation with iron- or aluminium salts. Often, the resulting products are voluminous, water-containing, amorphous hydroxides which show only limited flocculation properties and may possibly pose problems with the technical separation from the aqueous phase. The application of magnetite could be advantageous because magnetite is ferromagnetic and can be separated very quickly in a magnetic field. First of all, a simple preparation method for magnetite was studied. Pure magnetite could be prepared by mixing an iron(II) salt solution with an equivalent amount of sodium hydroxide at room temperature without oxidation by air. The required reaction time was only 3 hours. For the precipitation of heavy metals from an electroplating wastewater, a better metal elimination and smaller sludge volumes resulted with that artificially produced magnetite in comparison with a precipitation by NaOH. Thereby not only the adsorption of metals was established but also coagulation effects of the magnetite sludge with small metal hydroxide particles. By means of the experimental results. sorption of nickel and chromium was compiled as function of pH and precipitation time. Because freshly precipitated magnetite shows very good sorption and flocculation properties, and pH of precipitation may be lower, its use in high gradient magnetic separation (HGMS) could be more effective for metal elimination than magnetite powder. 相似文献
7.
Thomas Heberer Dirk Feldmann Kirsten Reddersen Hans‐Juergen Altmann Thomas Zimmermann 《洁净——土壤、空气、水》2002,30(1):24-33
In military out of area missions of the Bundeswehr, it can be necessary to produce drinking water even from highly polluted surface waters containing a variety of organic, inorganic, and microbiological contaminants. Thus, mobile drinking water purification systems must be able to remove such contaminants as far as possible to meet the requirements of the German and European drinking water regulation/directive. Presently, two novel drinking water purification units applying membrane filtration undergo intensive long‐term trials carried out by the Bundeswehr. If these trials positively proof the functionality of these units and their ability to remove all possible contaminants they shall substitute so far available devices which use large amounts of chemicals and charcoal filtration for water purification.In the course of a research project, the functionality of the new devices and their efficacy to remove high amounts of algae, microbes, and organic and inorganic pollutants are additionally tested in “worst‐case” field studies. In September 2000, the first mobile drinking water purification unit was tested at the Teltowkanal in Berlin, Germany.This canal was chosen because it carries high burdens of municipal sewage effluents. The results from the fatigue test confirmed the ability of the water purification unit to reduce the concentrations of all contaminants meeting the maximum tolerance levels set by the German/European drinking water regulation.The pre‐filtration device was very effective in removing algae and solid particles to protect the membranes from clogging and to enable an almost maintenance‐free operation. Residues of pharmaceuticals and some other organic contaminants have almost totally been removed from the surface water where they were detected at individual concentrations up to the μg/L‐level. 相似文献
8.
The release of genetically engineered microorganisms may occur from research laboratories of production plants. The most important pathway of release is via the sewage system and the sewage treatment plants into surface waters. The growth of these organisms might represent a risk to the environment. Therefore the growth of a genetically engineered strain of E. coli K-12 was investigated. Aqueous supernatant from sewage sludge of two domestic sewage plants was used as medium. This medium was treated with sterile filtration and amended with nutrients. The test strain E. coli K-12 W3110iqM15Nalr(pBR322) did not show permanent growth under the conditions employed. The result is interpreted by the presence of bacteriophages and the poor nutritional conditions in the medium. 相似文献
9.
Nitrification – Fundamentals of the Metabolism and Problems at the Use of Ammonia Oxidizers From an ecological point of view, a great problem results from the release of increasing amounts of inorganic and organic nitrogen compounds. Apart from gaseous nitrogen compounds, such as the greenhouse gas N2O, soluble nitrogen compounds such as ammonium cause difficulties. In recent years, great progress has been made regarding the reduction of the emission of sulfur and phosphorus compounds. Since there are no effective strategies for the decrease of nitrogen releases, the emission of such compounds has even been increasing. Therefore, great efforts are being made to eliminate the soluble nitrogen compounds in particular, for example in wastewater treatment plants. A decisive meaning befits the chemolithoautotrophic ammonia oxidizers. This review focuses on the ecological consequences of the release of ammonia in particular, the metabolism of the ammonia oxidizing microorganisms under consideration of the latest research results, and the problems that arise in the context of using these bacteria for the removal of ammonia. 相似文献
10.
The boron isotopic compositions of common synthetic boron products, municipal wastewaters from Switzerland, and three Swiss freshwater lakes were investigated. The δ11B values (δ11B values are normalized to the standard NIST SRM-951) of synthetic Na-borates (–0.4 to 7.6‰) and Ca-Na-borates (–13.4 to –4.9‰) overlap with those of natural borate minerals and hence suggest that the isotopic signal of anthropogenic boron is not modified during the manufacturing process. As a result it is possible to predict the isotopic composition of synthetic boron products and their potential impact upon contamination of water resources. The δ11B values of municipal wastewaters from two locations in northern Switzerland (–7.7 to –4.5‰) reflect utilization of Na/Ca- and/or Ca-borates depleted in 11B. Freshwater lakes from Switzerland (Lake Zürich, Greifensee, Lake Lugano) yielded a δ11B range of –1.7 to 7.1‰ and boron concentrations of 17 to 102 mg L–1. The boron isotopic ratios decrease with increasing boron concentrations, indicating mixing between anthropogenic boron with a low δ11B signature and meteoric boron with a heavier isotopic signal. We suggest that the isotopic composition of meteoric boron over central Europe has δ11B values in the range of ca. 10 to 20‰, whereas in coastal areas the marine component is larger with a higher 11B/10B ratio (δ11B ∼ 30‰). 相似文献