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Removal and seasonal variability of selected analgesics/anti-inflammatory, anti-hypertensive/cardiovascular pharmaceuticals and UV filters in wastewater treatment plant
2014
Golovko, Oksana | Kumar, Vimal | Fedorova, Ganna | Randak, Tomas | Grabic, Roman
Seasonal removal efficiency of 16 pharmaceuticals and personal care products was monitored in a wastewater treatment plant in České Budějovice, Czech Republic, over a period of 1 year (total amount of samples, n = 272). The studied compounds included four UV filters, three analgesics/anti-inflammatory drugs and nine anti-hypertensive/cardiovascular drugs. In most cases, elimination of the substances was incomplete, and overall removal rates varied strongly from −38 to 100 %. Therefore, it was difficult to establish a general trend for each therapeutic group. Based on the removal efficiencies (REs) over the year, three groups of target compounds were observed. A few compounds (benzophenon-1, valsartan, isradipine and furosemide) were not fully removed, but their REs were greater than 50 %. The second group of analytes, consisting of 2-phenylbenzimidazole-5-sulfonic acid, tramadol, sotalol, metoprolol, atenolol and diclofenac, showed a very low RE (lower than 50 %). The third group of compounds showed extremely variable RE (benzophenon-3 and benzophenon-4, codeine, verapamil, diltiazem and bisoprolol). There were significant seasonal trends in the observed REs, with reduced efficiencies in colder months.
显示更多 [+] 显示较少 [-]Concentration and characterization of airborne particles in Tehran’s subway system
2014
Kamani, Hosein | Hoseini, Mohammad | Seyedsalehi, Mahdi | Mahdavi, Yousef | Jaafari, Jalil | Safari, Gholam Hosein
Particulate matter is an important air pollutant, especially in closed environments like underground subway stations. In this study, a total of 13 elements were determined from PM₁₀and PM₂.₅samples collected at two subway stations (Imam Khomeini and Sadeghiye) in Tehran’s subway system. Sampling was conducted in April to August 2011 to measure PM concentrations in platform and adjacent outdoor air of the stations. In the Imam Khomeini station, the average concentrations of PM₁₀and PM₂.₅were 94.4 ± 26.3 and 52.3 ± 16.5 μg m⁻³in the platform and 81.8 ± 22.2 and 35 ± 17.6 μg m⁻³in the outdoor air, respectively. In the Sadeghiye station, mean concentrations of PM₁₀and PM₂.₅were 87.6 ± 23 and 41.3 ± 20.4 μg m⁻³in the platform and 73.9 ± 17.3 and 30 ± 15 μg m⁻³, in the outdoor air, respectively. The relative contribution of elemental components in each particle fraction were accounted for 43 % (PM₁₀) and 47.7 % (PM₂.₅) in platform of Imam Khomeini station and 15.9 % (PM₁₀) and 18.5 % (PM₂.₅) in the outdoor air of this station. Also, at the Sadeghiye station, each fraction accounted for 31.6 % (PM₁₀) and 39.8 % (PM₂.₅) in platform and was 11.7 % (PM₁₀) and 14.3 % (PM₂.₅) in the outdoor. At the Imam Khomeini station, Fe was the predominant element to represent 32.4 and 36 % of the total mass of PM₁₀and PM₂.₅in the platform and 11.5 and 13.3 % in the outdoor, respectively. At the Sadeghiye station, this element represented 22.7 and 29.8 % of total mass of PM₁₀and PM₂.₅in the platform and 8.7 and 10.5 % in the outdoor air, respectively. Other major crustal elements were 5.8 % (PM₁₀) and 5.3 % (PM₂.₅) in the Imam Khomeini station platform and 2.3 and 2.4 % in the outdoor air, respectively. The proportion of other minor elements was significantly lower, actually less than 7 % in total samples, and V was the minor concentration in total mass of PM₁₀and PM₂.₅in both platform stations.
显示更多 [+] 显示较少 [-]Degradation of 1,4-dioxane in water with heat- and Fe2+-activated persulfate oxidation
2014
Zhao, Long | Hou, Hong | Fujii, Ayuko | Hosomi, Masaaki | Li, Fasheng
This research investigated the 1,4-dioxane (1,4-D) degradation efficiency and rate during persulfate oxidation at different temperatures, with and without Fe²⁺addition, also considering the effect of pH and persulfate concentration on the oxidation of 1,4-D. Degradation pathways for 1,4-D have also been proposed based on the decomposition intermediates and by-products. The results indicate that 1,4-D was completely degraded with heat-activated persulfate oxidation within 3–80 h. The kinetics of the 1,4-D degradation process fitted well to a pseudo-first-order reaction model. Temperature was identified as the most important factor influencing the 1,4-D degradation rate during the oxidation process. As the temperature increased from 40 to 60 °C, the degradation rate improved significantly. At 40 °C, the addition of Fe²⁺also increased the 1,4-D degradation rate. Interestingly, at 50 and 60 °C, the 1,4-D degradation rate decreased slightly with the addition of Fe²⁺. This reduced degradation rate may be attributed to the rapid conversion of Fe²⁺to Fe³⁺and the production of an Fe(OH)₃precipitate which limited the ultimate oxidizing capability of persulfate with Fe²⁺under higher temperatures. Higher persulfate concentrations led to higher 1,4-D degradation rates, but pH adjustment had no significant effect on the 1,4-D degradation rate. The identification of intermediates and by-products in the aqueous and gas phases showed that acetaldehyde, acetic acid, glycolaldehyde, glycolic acid, carbon dioxide, and hydrogen ion were generated during the persulfate oxidation process. A carbon balance analysis showed that 96 and 93 % of the carbon from the 1,4-D degradation were recovered as by-products with and without Fe²⁺addition, respectively. Overall, persulfate oxidation of 1,4-D is promising as an economical and highly efficient technology for treatment of 1,4-D-contaminated water.
显示更多 [+] 显示较少 [-]Bioaccumulation and tissue distribution of organochlorine pesticides (OCPs) in freshwater fishes: a case study performed in Poyang Lake, China’s largest lake
2014
Zhao, Zhonghua | Wang, Yuyu | Zhang, Lu | Cai, Yongjiu | Chen, Yuwei
Concentrations and tissue distribution of organochlorine pesticides (OCPs) in different tissues of freshwater fish, silver carp (Hypophthalmichthys molitrix) and bighead carp (Aristichthys nobilis), collected from Poyang Lake, China’s largest shallow lake, and were studied. OCPs were detected with the observed concentrations ranging from 280.67 to 1,006.58 ng/g wet weight (ww) for bighead carp and from 67.28 to 930.06 ng/g ww for silver carp. Composition analysis demonstrated OCPs in both fish were from the same polluted environment, and then, the species-specific bioaccumulation might be mainly due to the different fish age as well as the different feeding habits elucidating from the stable carbon (δ¹³C) and nitrogen (δ¹⁵N) isotope analysis. Tissue distribution indicated that dietary intake was the major exposure route of OCPs for both fish and higher accumulation potency of OCPs by the hepatobiliary-related tissues (such as liver, kidney, bile, and heart). The higher metabolic activities of these tissues elucidating from the higher values of δ¹⁵N might be the potential-determined factor responsible for the tissue-specific accumulation.
显示更多 [+] 显示较少 [-]Iron-loaded mangosteen as a heterogeneous Fenton catalyst for the treatment of landfill leachate
2014
Laiju, A. R. | Sivasankar, T. | Nidheesh, P. V.
Iron-loaded mangosteen shell powder (Fe-MSP) was found as an effective heterogeneous Fenton catalyst for the treatment of stabilized landfill leachate. Sonolytically produced catalyst has higher efficiency than other catalysts. At the optimal conditions (pH 3, catalyst concentration of 1,750 mg/L and hydrogen peroxide concentration of 0.26 M), 81 % of the chemical oxygen demand (COD) was removed effectively from the landfill leachate. But, the efficiency of Fe-MSP was reduced in the first recycling due to the poisoning of active sites. A metal leaching study indicated that the degradation of the pollutant is mainly due to solid Fe ions present in Fe-MSP rather than the leached ferrous and ferric ions. Hydroxyl radical production in the system was confirmed by the Fenton oxidation of benzoic acid. Compared to the homogeneous Fenton process, the heterogeneous Fenton process using Fe-MSP had higher COD removal efficiency, indicating the practical applicability of the prepared catalyst.
显示更多 [+] 显示较少 [-]Faecal pollution loads in the wastewater effluents and receiving water bodies: a potential threat to the health of Sedibeng and Soshanguve communities, South Africa
2014
Teklehaimanot, Giorgis Z. | Coetzee, Martie A. A. | Momba, Maggy N. B.
The discharge of untreated or inadequately treated effluents has been identified among the activities responsible for the spread of a wide range of potentially infectious agents. The aim of this study was to determine whether inadequate treatment of wastewater and the faecal pollution load of effluents and receiving water bodies in Sedibeng District and Soshanguve peri-urban area of the Tshwane Metropolitan Municipality could be a potential threat to the health of the surrounding communities. Variations in the counts of faecal indicator bacteria and pathogenic microorganisms and compliance of the effluents and receiving water bodies with South African and World Health Organization standards were assessed between August 2011 and May 2012 using culture-based methods and molecular techniques. The overall quality of effluents did not comply with the South African special standard of no risk for unrestricted irrigation (zero Escherichia coli/100 ml). The quality of the receiving water bodies did not comply with South African regulatory limits set for domestic purposes (zero E. coli/100 ml, <30 faecal enterococci/100 ml and <1 somatic coliphages/100 ml), for full contact recreation (<20 somatic coliphages/100 ml) and aquaculture (<10 E. coli/100 ml) and WHO standards for full and intermediate contact recreational use (<1 E. coli/100 ml and <40 faecal enterococci/100 ml, respectively). The PCR results revealed the prevalence of pathogenic microorganisms; between 0 and 60 % of samples tested positive for Salmonella Typhimurium and Shigella dysenteriae, and between 20 and 60 % of samples tested positive for Vibrio cholerae. These findings demonstrated that potential health risks might be associated with the use of the target river waters for domestic, recreational and irrigation purposes. This study calls for a prompt intervention to improve wastewater management.
显示更多 [+] 显示较少 [-]Cadmium and copper toxicity in three marine macroalgae: evaluation of the biochemical responses and DNA damage
2014
Babu, M Yokesh | Palanikumar, L. | Nagarani, N. | Devi, V Janaki | Ramesh Kumar, S. | Ramakritinan, C. M. | Kumaraguru, A. K.
Marine macroalgae have evolved a different mechanism to maintain physiological concentrations of essential metal ions and non-essential metals. The objective of the present work was to evaluate the antioxidant response and DNA damage of copper and cadmium ions in three halophytes, namely, Acanthophora spicifera, Chaetomorpha antennina, and Ulva reticulata. Accumulation of copper was significantly higher (P < 0.05) than that of cadmium. Biochemical responses showed that copper was considerably more toxic than cadmium (P < 0.05). Decreases in glutathione content and fluctuations of super oxide dismutase, catalase, and glutathione peroxidase activities were observed corresponding to time and concentration of exposure. Interestingly, it was also observed that antioxidant levels decreased as a result of metal accumulation, which may be due to free radicals generated by copper and cadmium in seaweeds. The present study also showed that copper and cadmium increased oxidative stress and induced antioxidant defense systems against reactive oxygen species. The order of toxicity for metals in the studied seaweeds was U. reticulata > A. spicifera > C. antennina. DNA damage index analysis supported that copper was significantly (P < 0.05) more toxic than cadmium. Bioaccumulation, biochemical responses, and DNA damage observed in the here analyzed marine macroalgae after exposure to selected metals indicate that these marine organisms represent useful bioindicators of marine pollution.
显示更多 [+] 显示较少 [-]Seasonal variations in the chemical composition of particulate matter: a case study in the Po Valley. Part I: macro-components and mass closure
2014
Perrino, C. | Catrambone, M. | Dalla Torre, S. | Rantica, E. | Sargolini, T. | Canepari, S.
The seasonal variability in the mass concentration and chemical composition of atmospheric particulate matter (PM₁₀and PM₂.₅) was studied during a 2-year field study carried out between 2010 and 2012. The site of the study was the area of Ferrara (Po Valley, Northern Italy), which is characterized by frequent episodes of very stable atmospheric conditions in winter. Chemical analyses carried out during the study allowed the determination of the main components of atmospheric PM (macro-elements, ions, elemental carbon, organic matter) and a satisfactory mass closure was obtained. Accordingly, chemical components could be grouped into the main macro-sources of PM: soil, sea spray, inorganic compounds from secondary reactions, vehicular emission, organics from domestic heating, organics from secondary formation, and other sources. The more significant seasonal variations were observed for secondary inorganic species in the fine fraction of PM; these species were very sensitive to air mass age and thus to the frequency of stable atmospheric conditions. During the winter ammonium nitrate, the single species with the highest concentration, reached concentrations as high as 30 μg/m³. The intensity of natural sources was fairly constant during the year; increases in natural aerosols were linked to medium and long-range transport episodes. The ratio of winter to summer concentrations was roughly 2 for combustion product, close to 3 for secondary inorganic species, and between 2 and 3 for organics. The winter increase of organics was due to poorer atmospheric dispersion and to the addition of the emission from domestic heating. A similar winter to summer ratio (around 3) was observed for the fine fraction of PM.
显示更多 [+] 显示较少 [-]Deposition and regional distribution of HCHs and p,p′-DDX in the western and southern Tibetan Plateau: records from a lake sediment core and the surface soils
2014
Tao, Yu-Qiang | Lei, Guo-Liang | Xue, Bin | Yao, Shu-Chun | Pu, Yang | Zhang, Hu-Cai
Tibetan Plateau is the world’s highest plateau, which provides a unique location for the investigation of global fractionation of organochlorine pesticides (OCPs). In this study, deposition and regional distribution of HCHs and p,p′-DDX in the western and southern Tibetan Plateau were investigated by the records from a sediment core of Lake Zige Tangco and 24 surface soils. Concentration of ΣHCHs in the surface soils of the western Tibetan Plateau was much higher than that of the southern part. Maximum fluxes of α-, β-, and δ-HCH in the sediment core were 9.0, 222, and 21 pg cm⁻² year⁻¹, respectively, which appeared in the mid-1960s. Significant correlations were observed between concentrations of α- and β-HCH in both the surface soils and the sediment core. Concentrations of both α- and β-HCH increased with the inverse of the average annual temperature of these sites. γ-HCH became the dominant isomer of HCHs after the late 1970s, and reached the maximum flux of 160 pg cm⁻² year⁻¹in the early 1990s. There were no significant correlations between concentrations of γ-HCH and the other isomers in both the surface soils and the sediment core. The results suggested that there was input of Lindane at scattered sites in this area. In contrast to ΣHCHs, concentration of Σp,p′-DDX in the surface soils of the southern part was much higher than that of the western part. Maximum flux of Σp,p′-DDX was 44 pg cm⁻² year⁻¹, which appeared in the mid-1960s. Local emission of p,p′-DDT was found at scattered sites. This study provides novel data and knowledge for the OCPs in the western and southern Tibetan Plateau, which will help understand the global fractionation of OCPs in remote alpine regions.
显示更多 [+] 显示较少 [-]Bayesian importance parameter modeling of misaligned predictors: soil metal measures related to residential history and intellectual disability in children
2014
Onicescu, Georgiana | Lawson, Andrew B. | McDermott, Suzanne | Aelion, C Marjorie | Cai, Bo
In this paper, we propose a novel spatial importance parameter hierarchical logistic regression modeling approach that includes measurement error from misalignment. We apply this model to study the relationship between the estimated concentration of soil metals at the residence of mothers and the development of intellectual disability (ID) in their children. The data consist of monthly computerized claims data about the prenatal experience of pregnant women living in nine areas within South Carolina and insured by Medicaid during January 1, 1996 and December 31, 2001 and the outcome of ID in their children during early childhood. We excluded mother-child pairs if the mother moved to an unknown location during pregnancy. We identified an association of the ID outcome with arsenic (As) and mercury (Hg) concentration in soil during pregnancy, controlling for infant sex, maternal race, mother’s age, and gestational weeks at delivery. There is some indication that Hg has a slightly higher importance in the third and fourth months of pregnancy, while As has a more uniform effect over all the months with a suggestion of a slight increase in risk in later months.
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