124 research outputs found

    3–type curses in the euclidean space E6

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    11 pages.-- Dedicated to the sixtieth birthday of Professor Bang-Yen Chen.In [1] D. Blair gave a complete classification of 3–type curves in the space E3. In two recent papers [8] and [9] we gave a complete classification of 3– type curves in the spaces E4 and E5. In this paper we give a complete classification of 3–type curves in the space E6. This result completes the describing of 3–type curves in Euclidean spaces.Peer reviewe

    Water treatment plants and pharmaceutical residues in Catalonia and Italy

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    This study analyses the occurrence of commonly administered pharmaceuticals in urban and treated wastewater and surface waters in Catalonia and Italy, reviewing recently published investigations. The reported removal efficiencies in common municipal wastewater treatment plants are also discussed and pharmaceutical load discharged after these treatments are analysed. Finally, environmental risk posed by the presence of some of these compounds in surface water is discussed, and a case study highlighting the issue of pharmaceutical residues in the environment is presented. [Contrib Sci 10:135-150 (2014)

    Extraction and cleansing of data for a non-targeted analysis of high-resolution mass spectrometry data of wastewater

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    We provide a workflow to extract unidentified signals from chromatography-high resolution mass spectrometry (LC-HRMS) data of wastewater samples as a pre-step of a non-targeted analysis of dissolved organic matter (DOM). We provide detailed methodology on data processing and cleanup using MS processing software MZmine 2 and an own set of functions in R developed for wastewater analysis. The processing involves signal extraction, linear mass correction, reduction of noise, grouping of isotopologues, molecular formula assignment and merging of replicates. The article contains software settings and reasoning behind the choice of data extraction options. The supplementary information contains a script for the correction of signal masses using internal standards and templates of internal standard lists. We included a reproducible example as an R notebook with data cleansing workflow and data exported from MZmine. The data were used according to the described methodology in the article “A non-targeted high-resolution mass spectrometry data analysis of dissolved organic matter in wastewater treatment” by Verkh et al., 2018

    ADVANCED OXIDATION PROCESSES (AOPs) APPLIED FOR WASTEWATER AND DRINKING WATER TREATMENT. ELIMINATION OF PHARMACEUTICALS

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    Due to their insufficient removal in conventional wastewater treatments, advanced drinking and wastewater treatment options should be considered for the removal of pharmaceutically active compounds (PhACs) from urban, hospital and industrial wastewaters. This paper summarizes the current state-of-the-art in two often applied advanced oxidation processes (AOPs), namely TiO2 assisted photocatalysis and photo-Fenton process. Their possibilities in removing PhACs are discussed, giving examples for several most studied compounds

    Wastewater-based epidemiology to assess human exposure to personal care and household products – A review of biomarkers, analytical methods, and applications

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    Humans are nowadays exposed to numerous chemicals in our day-to-day life, including parabens, UV filters, phosphorous flame retardants/plasticizers, bisphenols, phthalates and alternative plasticizers, which can have different adverse effects to human health. Estimating human's exposure to these potentially harmful substances is, therefore, of paramount importance. Human biomonitoring (HBM) is the existing approach to assess exposure to environmental contaminants, which relies on the analysis of specific human biomarkers (parent compounds and/or their metabolic products) in biological matrices from individuals. The main drawback is its implementation, which involves complex cohort studies. A novel approach, wastewater-based epidemiology (WBE), involves estimating exposure from the analysis of biomarkers in sewage (a pooled urine and feces sample of an entire population). One of the key challenges of WBE is the selection of biomarkers which are specific to human metabolism, excreted in sufficient amounts, and stable in sewage. So far, literature data on potential biomarkers for estimating exposure to these chemicals are scattered over numerous pharmacokinetic and HBM studies. Hence, this review provides a list of potential biomarkers of exposure to more than 30 widely used chemicals and report on their urinary excretion rates. Furthermore, the potential and challenges of WBE in this particular field is discussed through the review of pioneer WBE studies, which for the first time explored applicability of this novel approach to assess human exposure to environmental contaminants. In the future, WBE could be potentially applied as an "early warning system", which could promptly identify communities with the highest exposure to environmental contaminants

    Fate and removal of pharmaceuticals and illicit drugs in conventional and membrane bioreactor wastewater treatment plants and by riverbank filtration

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    26 pages, 3 tables, 3 figures.Pharmaceutically active compounds (PhACs) and drugs of abuse (DAs) are two important groups of emerging environmental contaminants that have raised an increasing interest in the scientific community. A number of studies revealed their presence in the environment. This is mainly due to the fact that some compounds are not efficiently removed during wastewater treatment processes, being able to reach surface and groundwater and subsequently, drinking waters. This paper reviews the data regarding the levels of pharmaceuticals and illicit drugs detected in wastewaters and gives an overview of their removal by conventional treatment technologies (applying activated sludge) as well as advanced treatments such as membrane bioreactor. The paper also gives an overview of bank filtration practices at managed aquifer recharge sites and discusses the potential of this approach to mitigate the contamination by PhACs and DAs.This work has been supported by the EU project INNOVA-MED (INCO-CT-2006-517728) and by the Spanish Ministry of Science and Innovation Projects CTM2007-30524-E and CEMAGUA (CGL2007-64551).Peer reviewe

    Applicability of an on-line solid-phase extraction liquid chromatography – tandem mass spectrometry for the wastewater-based assessment of human exposure to chemicals from personal care and household products

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    Wastewater-based epidemiology (WBE) can be a useful complementary approach to assess human exposure to potentially harmful chemicals, including those from personal care and household products. In this work, a fully automated multiresidue method, based on on-line solid-phase extraction liquid chromatography – tandem mass spectrometry, was developed for the determination of 27 biomarkers of human exposure to selected chemicals from personal care and household products, including parabens, UV filters, phthalates and alternative plasticizers, phosphorous flame retardants/plasticizers (PFRs), and bisphenols. These biomarkers include both the parent compounds and their human metabolites. In addition, two oxidative stress biomarkers, 8-epi- prostaglandin F2α and 4-hydroxy nonenal mercapturic acid, were also considered in the study. The method was carefully optimized to tackle the challenges of analyzing compounds with different physico-chemical properties in a highly complex raw wastewater matrix, while model experiments were performed to investigate filtration losses and analyte stability. The applicability of the developed method was tested by analyzing raw wastewater from four European cities: Antwerp, Brussels (Belgium), Girona (Spain), and Zagreb (Croatia). Twenty-one biomarkers (10 parent compounds and 11 metabolites) were detected in all analyzed wastewater samples. The parent compounds with the highest mass loads were PFRs, parabens, and bisphenol S, while phthalate monoesters were the most prominent metabolites. The mass loads of most compounds were quite similar across cities, but geographic differences were observed for some biomarkers, such as metabolites of phthalates and alternative plasticizers. Exposure was then assessed for seven substances for which quantitative urinary excretion data are known. Our results indicate that safe reference values were exceeded for several contaminants, including butylated phthalates, bisphenol A, and tris(2- butoxyethyl) phosphate, particularly for toddlers. With this relatively simple method, which requires less sample manipulation, it is possible to promptly identify and monitor exposure to harmful chemicals at the population level using the WBE approach

    Suzbijanje korova u organskoj poljoprivredi

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    Organic agriculture as a production system based on ecological production, soil biological activity, biodiversity conservation and use of natural substances and processes is the only certified food production in Serbia. This system provides users of organic products with a guarantee that the end product is the result of consistent farming practices. Since 2010, three laws and a number of regulations underlying the development of this food production system have been adopted. The global organic market has seen a continuous rise in demand for organic products, whereas a relatively slight increase in their supply from organic crop growing areas of Serbia has been recorded. Reasons for the insufficient farmers' interest in organic agriculture include lack of information, lack of intermediate goods, fear of change and, very often, underestimation by conventional producers and professional agrarian circles. An important part of the mosaic-like fear of organic farming among producers is lack of knowledge regarding weed control methods in this production concept. As with other elements of organic farming practices, the basis for weed control rests on preventive action, as well as on direct methods of eliminating undesirable plants from agricultural biotopes.Organska poljoprivreda kao proizvodni sistem baziran ne ekološkoj proizvodnji, biološkoj aktivnosti zemljišta, očuvanju biodiverziteta, uz primenu prirodnih suspstanci i postupaka, jedina je sertifikovana proizvodnja hrane u Srbiji. Korisnicima organskih proizvoda se garantuje da je finalni proizvod rezultat dosledno sprovedene tehnologije gajenja. Od 2010 godine, usvojena su tri zakona i niz pravilnika, koji su osnov za razvoj ovog sistema proizvodnje hrane. Na svetskom tržištu organskih proizvoda, kontinuirano raste potražnja, dok je povećanje ponude ovih proizvoda iz agrosinuzija Srbije, u relativno blagom porastu. Razlozi nedovoljnog interesovanja proizvođača za bavljenje organskom poljoprivredom su neobaveštenost, nedostatak repro materijala, strah od promena i veoma često omalovažavanje od strane konvencionalnih proizvođača i stručne agrarne javnosti. Jedan od važnih elemenata u mozaiku kreiranja straha od organske poljoprivrede među proizvođačima je i nepoznavanje načina suzbijanja korova u ovom proizvodnom konceptu. Kao i u drugim elementima tehnologije gajenja, osnova suzbijanja korova jesu preventivne mere, ali postoje i direktni načini eliminisanja nepoželjnih biljaka iz agrobiotopa

    Analysis of pharmaceuticals in wastewater and removal using a membrane bioreactor

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    Much attention has recently been devoted to the life and behaviour of pharmaceuticals in the water cycle. In this study the behaviour of several pharmaceutical products in different therapeutic categories (analgesics and anti-inflammatory drugs, lipid regulators, antibiotics, etc.) was monitored during treatment of wastewater in a laboratory-scale membrane bioreactor (MBR). The results were compared with removal in a conventional activated-sludge (CAS) process in a wastewater-treatment facility. The performance of an MBR was monitored for approximately two months to investigate the long-term operational stability of the system and possible effects of solids retention time on the efficiency of removal of target compounds. Pharmaceuticals were, in general, removed to a greater extent by the MBR integrated system than during the CAS process. For most of the compounds investigated the performance of MBR treatment was better (removal rates >80%) and effluent concentrations of, e.g., diclofenac, ketoprofen, ranitidine, gemfibrozil, bezafibrate, pravastatin, and ofloxacin were steadier than for the conventional system. Occasionally removal efficiency was very similar, and high, for both treatments (e.g. for ibuprofen, naproxen, acetaminophen, paroxetine, and hydrochlorothiazide). The antiepileptic drug carbamazepine was the most persistent pharmaceutical and it passed through both the MBR and CAS systems untransformed. Because there was no washout of biomass from the reactor, high-quality effluent in terms of chemical oxygen demand (COD), ammonium content (N-NH(4)), total suspended solids (TSS), and total organic carbon (TOC) was obtained

    Assessing and forecasting the impacts of global change on Mediterranean rivers. The SCARCE Consolider project on Iberian basins

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    Introduction The Consolider-Ingenio 2010 project SCARCE, with the full title “Assessing and predicting effects on water quantity and quality in Iberian Rivers caused by global change” aims to examine and predict the relevance of global change on water availability, water quality, and ecosystem services in Mediterranean river basins of the Iberian Peninsula, as well as their socio-economic impacts. Starting in December 2009, it brought together a multidisciplinary team of 11 partner Spanish institutions, as well as the active involvement of water authorities, river basin managers, and other relevant agents as stakeholders. Methods The study areas are the Llobregat, Ebro, Jucar, and Guadalquivir river basins. These basins have been included in previous studies and projects, the majority of whom considered some of the aspects included in SCARCE but individually. Historical data will be used as a starting point of the project but also to obtain longer time series. The main added value of SCARCE project is the inclusion of scientific disciplines ranging from hydrology, geomorphology, ecology, chemistry, and ecotoxicology, to engineering, modeling, and economy, in an unprecedented effort in the Mediterranean area. The project performs data mining, field, and lab research as well as modeling and upscaling of the findings to apply them to the entire river basin. Results Scales ranging from the laboratory to river basins are addressed with the potential to help improve river basin management. The project emphasizes, thus, linking basic research and management practices in a single framework. In fact, one of the main objectives of SCARCE is to act as a bridge between the scientific and the management and to transform research results on management keys and tools for improving the River Basin Management Plans. Here, we outline the general structure of the project and the activities conducted within the ten Work Packages of SCARCE
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