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Biliary PAH metabolites, EROD activity and DNA damage in dab (Limanda limanda) from Seine Estuary (France) 全文
2013
Dévier, Marie-Hélène | Le Dû-Lacoste, Marie | Akcha, Farida | Morin, Bénédicte | Peluhet, Laurent | Le Menach, Karyn | Burgeot, Thierry | Budzinski, Hélène
The Seine Estuary is well known to be widely contaminated by organic pollutants and especially by polycyclic aromatic hydrocarbons (PAHs). Fish are known to metabolize PAHs, leading to different toxic effects at both cellular and sub-cellular levels. In this work, we studied the relationships between the 7-ethoxyresorufin-O-deethylase (EROD) activity in the liver, the level of DNA strand breaks in blood cells and the concentration of PAH metabolites in the bile of the sentinel flatfish species Limanda limanda. Muscle and liver samples were analysed for parent PAH levels. Female and male dabs of two size classes (juveniles and adults) were collected by trawling in two sites with different degrees of pollution during March and September 2005 and 2006. Significant effects of sex, age, site and season were demonstrated on EROD activity and the level of strand breaks. Parent PAH concentrations in dabs did not allow discriminating of the two sampling sites. However, for PAH metabolites, significant differences were observed with sites and seasons. Dabs collected at the mouth of the estuary appeared to be the most impacted when looking at the results obtained with the three selected markers. The significant correlations observed between the level of PAH metabolites and the level of DNA lesions showed the importance of a combined analysis of chemical and biochemical markers to correctly assess the contribution of chemical contamination to the toxic effects measured in situ in fish.
显示更多 [+] 显示较少 [-]Phosphorus loads from different urban storm runoff sources in southern China: a case study in Wenzhou City 全文
2013
Zhou, Dong | Bi, Chun-Juan | Chen, Zhen-Lou | Yu, Zhong-Jie | Wang, Jun | Han, Jing-Chao
Storm runoff from six types of underlying surface area during five rainfall events in two urban study areas of Wenzhou City, China was investigated to measure phosphorus (P) concentrations and discharge rates. The average event mean concentrations (EMCs) of total phosphorus (TP), total dissolved phosphorus (TDP), and particulate phosphorus (PP) ranged from 0.02 to 2.5 mg · L(-1), 0.01 to 0.48 mg · L(-1), and 0.02 to 2.43 mg · L(-1), respectively. PP was generally the dominant component of TP in storm runoff, while the major form of P varied over time, especially in roof runoff, where TDP made up the largest portion in the latter stages of runoff events. Both TP and PP concentrations were positively correlated with pH, total suspended solids (TSS), and biochemical oxygen demand (BOD)/chemical oxygen demand (COD) concentrations (p < 0.01), while TDP was positively correlated with BOD/COD only (p < 0.01). In addition, the EMCs of TP and PP were negatively correlated with maximum rainfall intensity (p < 0.05), while the EMCs of TDP positively correlated with the antecedent dry weather period (p < 0.05). The annual TP emission fluxes from the two study areas were 367.33 and 237.85 kg, respectively. Underlying surface type determined the TP and PP loadings in storm runoff, but regional environmental conditions affected the export of TDP more significantly. Our results indicate that the removal of particles from storm runoff could be an effective measure to attenuate P loadings to receiving water bodies.
显示更多 [+] 显示较少 [-]New trends in the analytical determination of emerging contaminants and their transformation products in environmental waters 全文
2013
Agüera, Ana | Martínez Bueno, María Jesús | Fernández-Alba, Amadeo R.
Since the so-called emerging contaminants were established as a new group of pollutants of environmental concern, a great effort has been devoted to the knowledge of their distribution, fate and effects in the environment. After more than 20 years of work, a significant improvement in knowledge about these contaminants has been achieved, but there is still a large gap of information on the growing number of new potential contaminants that are appearing and especially of their unpredictable transformation products. Although the environmental problem arising from emerging contaminants must be addressed from an interdisciplinary point of view, it is obvious that analytical chemistry plays an important role as the first step of the study, as it allows establishing the presence of chemicals in the environment, estimate their concentration levels, identify sources and determine their degradation pathways. These tasks involve serious difficulties requiring different analytical solutions adjusted to purpose. Thus, the complexity of the matrices requires highly selective analytical methods; the large number and variety of compounds potentially present in the samples demands the application of wide scope methods; the low concentrations at which these contaminants are present in the samples require a high detection sensitivity, and high demands on the confirmation and high structural information are needed for the characterisation of unknowns. New developments on analytical instrumentation have been applied to solve these difficulties. Furthermore and not less important has been the development of new specific software packages intended for data acquisition and, in particular, for post-run analysis. Thus, the use of sophisticated software tools has allowed successful screening analysis, determining several hundreds of analytes, and assisted in the structural elucidation of unknown compounds in a timely manner.
显示更多 [+] 显示较少 [-]An assessment of dioxin contamination from the intermittent operation of a municipal waste incinerator in Japan and associated remediation 全文
2013
Takeda, Nobuo | Takaoka, Masaki
Significant dioxin (polychlorinated dibenzo-para-dioxins (PCDDs)/polychlorinated dibenzo-furans (PCDFs)) pollution from a municipal solid waste incinerator was discovered in 1997 in Osaka prefecture/Japan. The cause and mechanism of pollution was identified by a detailed assessment of the environment and incinerator plant. The primary sources of PCDD/PCDF pollution were high dioxin releases from an intermittently operated waste incinerator with PCDD/PCDF emissions of 150 ng-TEQ/Nm³. PCDD/PCDF also accumulated in the wet scrubber system (3,000 μg TEQ/L) by adsorption and water recirculation in the incinerator. Scrubber water was air-cooled with a cooling tower located on the roof of the incinerator. High concentrations of dioxins in the cooling water were released as aerosols into the surrounding and caused heavy soil pollution in the area near the plant. These emissions were considered as the major contamination pathway from the plant. Decontamination and soil remediation in and around the incinerator plant were conducted using a variety of destruction technologies (including incineration, photochemical degradation and GeoMelt technology). Although the soil remediation process was successfully finished in December 2006 about 3 % of the waste still remains. The case demonstrates that releases from incinerators which do not use best available technology or which are not operated according to best environmental practices can contaminate their operators and surrounding land. This significant pollution had a large impact on the Japanese government’s approach toward controlling dioxin pollution. Since this incident, a ministerial conference on dioxins has successfully strengthened control measures.
显示更多 [+] 显示较少 [-]Core–shell magnetite-silica dithiocarbamate-derivatised particles achieve the Water Framework Directive quality criteria for mercury in surface waters 全文
2013
Lopes, C. B. | Figueira, P. | Tavares, D. S. | Lin, Z. | Daniel-da-Silva, A. L. | Duarte, A. C. | Rocha, J. | Trindade, T. | Pereira, E.
Core–shell magnetite-silica dithiocarbamate-derivatised particles achieve the Water Framework Directive quality criteria for mercury in surface waters 全文
2013
Lopes, C. B. | Figueira, P. | Tavares, D. S. | Lin, Z. | Daniel-da-Silva, A. L. | Duarte, A. C. | Rocha, J. | Trindade, T. | Pereira, E.
The sorption capacity of nanoporous titanosilicate Engelhard titanosilicate number 4 (ETS-4) and silica-coated magnetite particles derivatised with dithiocarbamate groups towards Hg(II) was evaluated and compared in spiked ultra-pure and spiked surface-river water, for different batch factors. In the former, and using a batch factor of 100 m(3)/kg and an initial Hg(II) concentrations matching the maximum allowed concentration in an effluent discharge, both materials achieve Hg(II) uptake efficiencies in excess of 99 % and a residual metal concentration lower than the guideline value for drinking water quality. For the surface-river water and the same initial concentration, the Hg(II) uptake efficiency of magnetite particles is outstanding, achieving the quality criteria established by the Water Framework Directive (concerning Hg concentration in surface waters) using a batch factor of 50 m(3)/kg, while the efficiency of ETS-4 is significantly inferior. The dissimilar sorbents' Hg(II) removal efficiency is attributed to different uptake mechanisms. This study also highlights the importance of assessing the effective capacity of the sorbents under realistic conditions in order to achieve trustable results.
显示更多 [+] 显示较少 [-]Core-shell magnetite-silica dithiocarbamate-derivatised particles achieve the Water Framework Directive quality criteria for mercury in surface waters 全文
1000 | 2013
Lopes, C. B. | Figueira, P. | Tavares, D. S. | Lin, Z. | Daniel-da-Silva, A. L. | Duarte, A. C. | Rocha, J. | Trindade, T. | Pereira, E.
The sorption capacity of nanoporous titanosilicate Engelhard titanosilicate number 4 (ETS-4) and silica-coated magnetite particles derivatised with dithiocarbamate groups towards Hg(II) was evaluated and compared in spiked ultra-pure and spiked surface-river water, for different batch factors. In the former, and using a batch factor of 100 m(3)/kg and an initial Hg(II) concentrations matching the maximum allowed concentration in an effluent discharge, both materials achieve Hg(II) uptake efficiencies in excess of 99 % and a residual metal concentration lower than the guideline value for drinking water quality. For the surface-river water and the same initial concentration, the Hg(II) uptake efficiency of magnetite particles is outstanding, achieving the quality criteria established by the Water Framework Directive (concerning Hg concentration in surface waters) using a batch factor of 50 m(3)/kg, while the efficiency of ETS-4 is significantly inferior. The dissimilar sorbents' Hg(II) removal efficiency is attributed to different uptake mechanisms. This study also highlights the importance of assessing the effective capacity of the sorbents under realistic conditions in order to achieve trustable results.
显示更多 [+] 显示较少 [-]Dissolved trace element biogeochemistry of a tropical river, Southwestern India 全文
2013
Tripti, M | Gurumurthy, G P | Balakrishna, K | Chadaga, M D
River Swarna, a small tropical river originating in Western Ghats (at an altitude of 1,160 m above mean sea level) and flowing in the southwest coast of India discharges an average of 54 m³s⁻¹ of water into the Arabian Sea, of which significant part is being discharged during the monsoon. No studies have been made yet on the water chemistry of the Swarna River basin, even as half a million people of Udupi district use it for domestic and irrigational purposes. As large community in this region depends on the freshwater of Swarna River, there is an urgent need to study the trace element geochemistry of this west flowing river for better water management and sustainable development. The paper presents the results on the biogeochemistry of dissolved trace elements in the Swarna River for a period of 1 year. The results obtained on the trace elements show seasonal effect on the concentrations as well as behavior and thus forming two groups, discharge driven (Li, Be, Al, V, Cr, Ni, Zr, In, Pb, Bi and U) and base flow driven (groundwater input; Mn, Fe, Co, Cu, Ga, Zn, As, Se, Rb, Sr, Ag, Cd, Cs, Ba and Tl) trace elements in Swarna River. The biogeochemical processes explained through Hierarchical Cluster Analysis show complexation of Fe, Ga and Ba with dissolved organic carbon, redox control over Mn and Tl and biological control over V and Ni. Also, the water quality of Swarna River remains within the permissible limits of drinking water standards.
显示更多 [+] 显示较少 [-]Nanocellulosic fiber-modified carbon paste electrode for ultra trace determination of Cd (II) and Pb (II) in aqueous solution 全文
2013
Rajawat, Deepak Singh | Kardam, Abhishek | Srivastava, Shalini | Satsangee, Soami Piara
In recent years, increasing awareness of the environmental impact of heavy metals has prompted a demand for monitoring and decontaminating industrial wastes prior to discharging into natural water bodies. This paper describes the preparation and electrochemical application of carbon paste electrode modified with nanocellulosic fibers for the determination of cadmium and lead in water samples using anodic stripping voltammetry. First, cadmium and lead were adsorbed on the carbon paste electrode surface at open circuit potential, followed by anodic stripping voltammetric scan from -1 to 0 V. Different factors affecting sensitivity and precision of the electrode, including accumulating solvent, pH of the accumulating solvent, accumulation time, supporting electrolyte, and scan rate were investigated. The proposed method was also applied to the determination of Cd (II) and Pb (II) in the presence of other interfering metal ions and cetyl trimethyl ammonium bromide, sodium dodecyl sulfate, and Triton X-100 as a representative of cationic, anionic, and neutral surfactants. Linear calibration curves were obtained in the concentration ranges of 150–650 μg L⁻¹ and 80–300 μg L⁻¹, respectively, for cadmium and lead at an accumulated time of 10 min with limits of detection 88 and 33 μg L⁻¹. Optimized working conditions are defined as acetate buffer of pH 5 as accumulating solvent, hydrochloric acid as supporting electrolyte, and scan rate 50 mV/s. This technique does not use mercury and therefore has a positive environmental benefit. The method is reasonably sensitive and selective and has been successfully applied to the determination of trace amounts of Cd (II) and Pb (II) in water samples.
显示更多 [+] 显示较少 [-]Nanoscale materials and their use in water contaminants removal—a review 全文
2013
Mohmood, Iram | Lopes, Cláudia Batista | Lopes, Isabel | Aḥmad, Iqbāl | Duarte, Armando C. | Pereira, Eduarda
Nanoscale materials and their use in water contaminants removal—a review 全文
2013
Mohmood, Iram | Lopes, Cláudia Batista | Lopes, Isabel | Aḥmad, Iqbāl | Duarte, Armando C. | Pereira, Eduarda
Water scarcity is being recognized as a present and future threat to human activity and as a consequence water purification technologies are gaining major attention worldwide. Nanotechnology has many successful applications in different fields but recently its application for water and wastewater treatment has emerged as a fast-developing, promising area. This review highlights the recent advances on the development of nanoscale materials and processes for treatment of surface water, groundwater and industrial wastewater that are contaminated by toxic metals, organic and inorganic compounds, bacteria and viruses. In addition, the toxic potential of engineered nanomaterials for human health and the environment will also be discussed.
显示更多 [+] 显示较少 [-]Nanoscale materials and their use in water contaminants removal-a review 全文
2013
Mohmood, Iram | Lopes, Cláudia Batista | Lopes, Isabel | Ahmad, Iqbal | Duarte, Armando C. | Pereira, Eduarda
Water scarcity is being recognized as a present and future threat to human activity and as a consequence water purification technologies are gaining major attention worldwide. Nanotechnology has many successful applications in different fields but recently its application for water and wastewater treatment has emerged as a fast-developing, promising area. This review highlights the recent advances on the development of nanoscale materials and processes for treatment of surface water, groundwater and industrial wastewater that are contaminated by toxic metals, organic and inorganic compounds, bacteria and viruses. In addition, the toxic potential of engineered nanomaterials for human health and the environment will also be discussed. | Iram Mohmood (SFRH/BD/74410/2010), Claúdia Batista Lopes (SFRH/BPD/45156/2008), Isabel Lopes, Iqbal Ahmad, Armando Duarte and Eduarda Pereira are grateful to the Portuguese Foundation for Science and Technology (FCT), FSE and POPH funds (Programa Ciência 2007) and the Aveiro University Research Institute/Centre for Environmental and Marine Studies (CESAM) for partial financial supports. | published
显示更多 [+] 显示较少 [-]Health care industries: potential generators of genotoxic waste 全文
2013
Sharma, Pratibha | Manish Kumar, | Mathur, N. | Singh, A. | Bhatnagar, P. | Sogani, M.
Health care waste includes all the waste generated by health care establishments, research facilities, and laboratories. This constitutes a variety of chemical substances, such as pharmaceuticals, radionuclides, solvents, and disinfectants. Recently, scientists and environmentalists have discovered that wastewater produced by hospitals possesses toxic properties due to various toxic chemicals and pharmaceuticals capable of causing environmental impacts and even lethal effects to organisms in aquatic ecosystems. Many of these compounds resist normal wastewater treatment and end up in surface waters. Besides aquatic organisms, humans can be exposed through drinking water produced from contaminated surface water. Indeed, some of the substances found in wastewaters are genotoxic and are suspected to be potential contributors to certain cancers. The aim of this study was to evaluate the genotoxic and cytotoxic potential of wastewaters from two hospitals and three clinical diagnostic centers located in Jaipur (Rajasthan State), India using the prokaryotic Salmonella mutagenicity assay (Ames assay) and the eukaryotic Saccharomyces cerevisiae respiration inhibition assay. In the Ames assay, untreated wastewaters from both of the health care sectors resulted in significantly increased numbers of revertant colonies up to 1,000-4,050 as measured by the Salmonella typhimurium TA98 and TA100 strains (with and without metabolic activation) after exposure to undiluted samples, which indicated the highly genotoxic nature of these wastewaters. Furthermore, both hospital and diagnostic samples were found to be highly cytotoxic. Effective concentrations at which 20 % (EC20) and 50 % (EC50) inhibition of the respiration rate of the cells occurred ranged between ∼0.00 and 0.52 % and between 0.005 and 41.30 % (calculated with the help of the MS excel software XLSTAT 2012.1.01; Addinsoft), respectively, as determined by the S. cerevisiae assay. The results indicated that hospital wastewaters contain genotoxic and cytotoxic components. In addition, diagnostic centers also represent small but significant sources of genotoxic and cytotoxic wastes.
显示更多 [+] 显示较少 [-]Phytoremediation potential of Petunia grandiflora Juss., an ornamental plant to degrade a disperse, disulfonated triphenylmethane textile dye Brilliant Blue G 全文
2013
Watharkar, Anuprita D. | Khandare, Rahul V. | Kamble, Apurva A. | Mulla, Asma Y. | Govindwar, Sanjay P. | Jadhav, Jyoti P.
Phytoremediation provides an ecofriendly alternative for the treatment of pollutants like textile dyes. The purpose of this study was to explore phytoremediation potential of Petunia grandiflora Juss. by using its wild as well as tissue-cultured plantlets to decolorize Brilliant Blue G (BBG) dye, a sample of dye mixture and a real textile effluent. In vitro cultures of P. grandiflora were obtained by seed culture method. The decolorization experiments were carried out using wild as well as tissue-cultured plants independently. The enzymatic analysis of the plant roots was performed before and after decolorization of BBG. Metabolites formed after dye degradation were analyzed using UV–vis spectroscopy, high-performance liquid chromatography, Fourier transform infrared spectroscopy, and gas chromatography–mass spectrometry. Phytotoxicity studies were performed. Characterization of dye mixture and textile effluent was also studied. The wild and tissue-cultured plants of P. grandiflora showed the decolorized BBG up to 86 %. Significant increase in the activities of lignin peroxidase, laccase, NADH-2,6-dichlorophenol-indophenol reductase, and tyrosinase was found in the roots of the plants. Three metabolites of BBG were identified as 3-{[ethyl(phenyl)amino]methyl}benzenesulfonic acid, 3-{[methyl (phenyl)amino]methyl}benzenesulfonic amino acid, and sodium-3-[(cyclohexa-2,5-dien-1-ylideneamino)methyl]benzenesulfonate. Textile effluent sample and a synthetic mixture of dyes were also decolorized by P. grandiflora. Phytotoxicity test revealed the nontoxic nature of metabolites. P. grandiflora showed the potential to decolorize and degrade BBG to nontoxic metabolites. The plant has efficiently treated a sample of dye mixture and textile effluent.
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