خيارات البحث
النتائج 1 - 10 من 17
The occurrence of anti-retroviral compounds used for HIV treatment in South African surface water
2015
Wood, Timothy Paul | Duvenage, Cornelia S.J. | Rohwer, Egmont
The study and quantification of personal care products, such as pharmaceuticals, in surface water has become popular in recent years; yet very little description of these compounds’ presence in South African surface water exists in the literature. Antiretrovirals (ARVs), used to treat human immunodeficiency virus (HIV) are rarely considered within this field. A new method for the simultaneous quantification of 12 antiretroviral compounds in surface water using the standard addition method is described. Water samples were concentrated by a generic automated solid phase extraction method and analysed by ultra-high pressure liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). Substantial matrix effect was encountered in the samples with an average method detection limit of 90.4 ng/L. This is the first reported countrywide survey of South African surface water for the quantification of these compounds with average concentrations ranging between 26.5 and 430 ng/L.
اظهر المزيد [+] اقل [-]Persistent and emerging micro-organic contaminants in Chalk groundwater of England and France
2015
Lapworth, D.J. | Baran, N. | Stuart, M.E. | Manamsa, K. | Talbot, J.
The Chalk aquifer of Northern Europe is an internationally important source of drinking water and sustains baseflow for surface water ecosystems. The areal distribution of microorganic (MO) contaminants, particularly non-regulated emerging MOs, in this aquifer is poorly understood. This study presents results from a reconnaissance survey of MOs in Chalk groundwater, including pharmaceuticals, personal care products and pesticides and their transformation products, conducted across the major Chalk aquifers of England and France. Data from a total of 345 sites collected during 2011 were included in this study to provide a representative baseline assessment of MO occurrence in groundwater. A suite of 42 MOs were analysed for at each site including industrial compounds (n=16), pesticides (n=14) and pharmaceuticals, personal care and lifestyle products (n=12). Occurrence data is evaluated in relation to land use, aquifer exposure, well depth and depth to groundwater to provide an understanding of vulnerable groundwater settings.
اظهر المزيد [+] اقل [-]Tracking changing X-ray contrast media application to an urban-influenced karst aquifer in the Wadi Shueib, Jordan
2015
Zemann, Moritz | Wolf, Leif | Grimmeisen, Felix | Tiehm, Andreas | Klinger, J. (Jochen) | Hötzl, Heinz | Goldscheider, Nico
Sewage input into a karst aquifer via leaking sewers and cesspits was investigated over five years in an urbanized catchment. Of 66 samples, analyzed for 25 pharmaceuticals, 91% indicated detectable concentrations. The former standard iodinated X-ray contrast medium (ICM) diatrizoic acid was detected most frequently. Remarkably, it was found more frequently in groundwater (79%, median: 54 ng/l) than in wastewater (21%, 120 ng/l), which is supposed to be the only source in this area. In contrast, iopamidol, a possible substitute, spread over the aquifer during the investigation period whereas concentrations were two orders of magnitude higher in wastewater than in groundwater. Knowledge about changing application of pharmaceuticals thus is essential to assess urban impacts on aquifers, especially when applying mass balances. Since correlated concentrations provide conclusive evidence that, for this catchment, nitrate in groundwater rather comes from urban than from rural sources, ICM are considered useful tracers.
اظهر المزيد [+] اقل [-]Analysis of chloramphenicol residues in the macroalgae Ulva lactuca through ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS)
2015
Leston, Sara | Freitas, Andreia | Nunes, Margarida | Barbosa, Jorge | Pardal, Miguel Ângelo | Ramos, Fernando
Antibiotic use is a well-described practice to promote animal health whether for prevention or treatment. Nonetheless, it can also cause a number of potentially harmful effects that dictate the need to implement regulation to assure a reduction of hazards to the consumers and the environment. Chloramphenicol (CAP) is a broad-spectrum antibacterial excluded from use in animal food production but despite this, reports of illegal use still persist. More recently, awareness has risen that the surrounding natural ecosystems can potentially be contaminated by pharmaceuticals and the extent of their effects in non-target organisms is already under the scope of researchers. To face the demanding new challenges a methodology for the determination of CAP in the green macroalgae Ulva lactuca by ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) was developed, optimized and fully validated following the guidelines of the EC Decision 2002/657.
اظهر المزيد [+] اقل [-]Assessing potential risks of wastewater discharges to benthic biota: An integrated approach to biomarker responses in clams (Ruditapes philippinarum) exposed under controlled conditions
2015
Maranho, L.A. | DelValls, T.A. | Martín-Díaz, M.L.
Marine clams Ruditapes philippinarum were exposed under laboratory conditions to sediments sampled at five sites affected by wastewater effluents at the Bay of Cádiz (SW, Spain). Contamination and early biological stress were determined. Metabolism and antioxidant system differed according to seasons. Health status diminished in summer. Metabolism of detoxification, and oxidative effect were related to concentration of metals, PAH, secondary alkane sulfonates (SAS) and antibiotics in winter. Antioxidant system and DNA damage were linked to metals and pharmaceutical products. Phase I and antioxidant system were associated to PAH and SAS in summer. Oxidative stress and effects were related to pharmaceuticals. Phase II was linked to metals and pharmaceuticals. Seasonality of sediment contamination by organic compounds and biological responses was determined. Clams were useful bioindicators, since the set of biomarkers applied was validated as potential tools for sediment quality assessment of wastewater discharges areas.
اظهر المزيد [+] اقل [-]The mussel caging approach in assessing biological effects of wastewater treatment plant discharges in the Gulf of Finland (Baltic Sea)
2015
Turja, Raisa | Lehtonen, Kari K. | Meierjohann, Axel | Brozinski, Jenny-Maria | Vahtera, Emil | Soirinsuo, Anna | Sokolov, Alexander | Snoeijs, Pauline | Budzinski, Hélène | Devier, Marie-Hélène | Peluhet, Laurent | Pääkkönen, Jari-Pekka | Viitasalo, Markku | Kronberg, Leif
Biological effects of wastewater treatment plant (WWTP) effluents were investigated in Baltic mussels (Mytilus trossulus) caged for one month 800m and 1100m from the WWTP discharge site and at a reference site 4km away. Significant antioxidant, genotoxic and lysosomal responses were observed close to the point of the WWTP discharge. Passive samplers (POCIS) attached to the cages indicated markedly higher water concentrations of various pharmaceuticals at the two most impacted sites. Modeling the dispersal of a hypothetical passive tracer compound from the WWTP discharge site revealed differing frequencies and timing of the exposure periods at different caging sites. The study demonstrated for the first time the effectiveness of the mussel caging approach in combination with passive samplers and the application of passive tracer modeling to examine the true exposure patterns at point source sites such as WWTP pipe discharges in the Baltic Sea.
اظهر المزيد [+] اقل [-]Which coastal and marine environmental contaminants are truly emerging?
2015
Maruya, Keith A. | Dodder, Nathan G. | Tang, Chi-Li | Lao, Wenjian | Tsukada, David
To better understand the past and present impact of contaminants of emerging concern (CECs) in coastal and marine ecosystems, archived samples were analyzed for a broad suite of analytes, including pharmaceuticals and personal care products (PPCPs), flame retardants (including PBDEs), perfluorinated compounds (PFCs), and current-use pesticides. Surface sediment, mussels (Mytilus spp.) and sediment core samples collected from the California (USA) coast were obtained from environmental specimen banks. Selected CECs were detected in recent surface sediments, with nonylphenol (4-NP), its mono- and di-ethoxylates (NP1EO and NP2EO), triclocarban, and pyrethroid insecticides in the greatest abundance. Alkylphenols, triclocarban, and triclosan were present in sediment core segments from the 1970s, as well as in Mytilus tissue collected during the 1990s. Increasing concentrations of some CECs (e.g., miconazole, triclosan) were observed in the surface layers (ca. 2007) of a sediment core, in contrast to peak concentrations of 4-NP and triclocarban corresponding to input during the 1970s, and an apparent peak input for PBDEs during the 1990s. These results suggest that chemicals sometimes referred to as “emerging” (e.g., alkylphenols, triclocarban) have been present in the aquatic environment for several decades and are decreasing in concentration, whereas others (e.g., miconazole, triclosan) are increasing.
اظهر المزيد [+] اقل [-]Antibiotic resistance pattern and gene expression of non-typhoid Salmonella in riversheds
2015
Hsu, Chao-Yu | Hsu, Bing-Mu | Ji, Wen-Tsai | Chen, Jung-Sheng | Hsu, Tsui-Kang | Ji, Dar-Der | Tseng, Shao-Feng | Chiu, Yi-Chou | Kao, Po-Min | Huang, Youli
In this study, antibiotic resistance and major phenol and genotypes of non-typhoid Salmonella spp. from riversheds in Taiwan were examined. In 236 water samples tested, 54 (22.9 %) contained Salmonella spp. Fifteen Salmonella serovars were identified from the Salmonella isolates, and some common serovars are associated with infections of human and livestock, including Albany (27.8 %), Newport (14.8 %), Bareilly (13.0 %), Derby (11.1 %), and Typhimurium (7.4 %). Various environmental factors may also affect the presence and proportion of different serovars in the receiving waters. In contrast, serovars with narrower range of hosts, e.g., Dublin, were rarely detected. The Salmonella isolates were subjected to eight antibiotics for drug resistance, and 51.9 % of the samples were resistant to at least one tested antibiotics. Tetracycline and sulfadiazine were the two most ineffective antibiotics against the Salmonella isolates, and the results were indicative of long-term antibiotics abuse as fodder supplements in animal husbandry. The more commonly detected serovars such as Albany, Derby, and Typhimurium were also more likely to be resistant to multiple antibiotics. Finally, a significant correlation was observed between resistance to chloramphenicol and the resistance gene cmlA, suggesting that the resistance genotypes could persist in the environment even long after prohibition of the drug use. The high prevalence of antibiotic-resistant Salmonella spp. infers elevated infection risks that must be further examined.
اظهر المزيد [+] اقل [-]A multi-residue method for determination of 70 organic micropollutants in surface waters by solid-phase extraction followed by gas chromatography coupled to tandem mass spectrometry
2015
Terzopoulou, Evangelia | Voutsa, Dimitra | Kaklamanos, George
A multi-residue method, based on gas chromatography coupled to tandem mass spectrometry (GC-MS/MS), has been developed for the determination of 70 organic micropollutants from various chemical classes (organochlorinated, organophosphorous, triazines, carbamate and urea, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, pharmaceuticals, phenols, etc.) in surface waters. A single-step SPE extraction using OASIS HLB cartridges was employed for the recovery of target micropollutants. The method has been validated according to monitoring performance criteria of the Water Framework Directive, taking into account the approved guidelines on quality assurance and quality control. The recoveries ranged from 60 to 110 %, the coefficient of variation from 0.84 to 27.4 %, and the uncertainty from 6 to 37 %. The LOD varied from 6.0 to 40 ng/L. The limits of quantification for the priority pollutants anthracene, alachlor, atrazine, benzo(a)pyrene, chlorfenvinphos, diuron, isoproturon, nonylphenol, simazine, and terbutryn fulfill the criterion of <30 % of the relevant environmental standards. The method was employed to investigate the water quality in the basin of a transboundary river, Strymonas, in NE Greece during three sampling campaigns conducted in the year 2013. Thirty-nine compounds were detected in the river water. Metolachlor, diuron, isoproturon, salicylic acid, chlorfenvinphos, 1,2-benzanthracene, pyrene, diflubenzuron, and carbaryl exhibited the highest detection frequencies.
اظهر المزيد [+] اقل [-]Toxicity of anthelmintic drugs (fenbendazole and flubendazole) to aquatic organisms
2015
Wagil, Marta | Białk-Bielińska, Anna | Puckowski, Alan | Wychodnik, Katarzyna | Maszkowska, Joanna | Mulkiewicz, Ewa | Kumirska, Jolanta | Stepnowski, Piotr | Stolte, Stefan
Flubendazole (FLU) and fenbendazole (FEN) belong to benzimidazoles—pharmaceuticals widely used in veterinary and human medicine for the treatment of intestinal parasites as well as for the treatment of systemic worm infections. In recent years, usage of these drugs increased, which resulted in a larger contamination of the environment and possible negative effects on biota. Hence, in our research, we investigated an aquatic ecotoxicity of these pharmaceuticals towards: marine bacteria (Vibrio fischeri), green algae (Scenedesmus vacuolatus), duckweed (Lemna minor) and crustacean (Daphnia magna). Ecotoxicity tests were combined with chemical analysis in order to investigate the actual exposure concentration of the compounds used in the experiment as well as to stability and adsorption studies. As a result, study evaluating sensitivity of different aquatic organisms to these compounds and new ecotoxicological data is presented. The strongest negative impact of FLU and FEN was observed to D. magna.
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