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Hypertension prevalence and living conditions related to air pollution: results of a national epidemiological study in Lebanon Полный текст
2018
Salameh, Pascale | Chahine, Mirna | Hallit, Souheil | Farah, Rita | Zeidan, RoubaKaren | Asmar, Roland | Hosseiny, Hassan
Hypertension is a risk factor of several diseases, linked to high mortality and morbidity, particularly in developing countries. Some studies have linked indoor and outdoor pollution exposure items to hypertension, but results were inconsistent. Our objective was to assess the association of living conditions related to air pollution to hypertension in Lebanon, a Middle Eastern country. A national cross-sectional study was conducted all over Lebanon. Blood pressure and its related medications were assessed to be able to classify participants as hypertensive or not. Moreover, in addition to living conditions related to air pollution exposure, we assessed potential predictors of hypertension, including sociodemographic characteristics, self-reported health information and biological measurements. Furthermore, we assessed dose-effect relationship of air pollution items in relation with hypertension. Living conditions related to indoor and outdoor air pollution exposures were associated with hypertension, with or without taking biological values into account. Moreover, we found a dose-effect relationship of exposure with risk of disease (15% increase in risk of disease for every additional pollution exposure item), after adjustment for sociodemographics and biological characteristics (Ora = 1.15 [1.03–1.28]). Although additional studies would be necessary to confirm these findings, interventions should start to sensitize the population about the effect of air pollution on chronic diseases. The work on reducing pollution and improving air quality should be implemented to decrease the disease burden on the population and health system.
Показать больше [+] Меньше [-]Treatment of soak liquor and bioelectricity generation in dual chamber microbial fuel cell Полный текст
2018
Sathishkumar, Kuppusamy | Narenkumar, Jayaraman | Selvi, Adikesavan | Murugan, Kadarkarai | Babujanarthanam, Ranganathan | Rajasekar, Aruliah
The discharge of untreated soak liquor from tannery industry causes severe environmental pollution. This study is characterizing the soak liquor as a substrate in the microbial fuel cell (MFC) for remediation along with electricity generation. The dual chamber MFC was constructed and operated. Potassium permanganate was used as cathode solution and carbon felt electrode as anodic and cathodic material, respectively. The soak liquor was characterized by electrochemical studies viz., cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and polarization studies, respectively. The removal percentage of protein, lipid, and chemical oxygen demand (COD) were measured before and after treatment with MFC. The results of MFC showed a highest current density of 300 mA/cm² and a power density of 92 mW/m². The removal of COD, protein, and lipid were noted as 96, 81, and 97% respectively during MFC process. This MFC can be used in tannery industries for treating soak liquor and simultaneous electricity generation.
Показать больше [+] Меньше [-]Fertilizer effects of composted materials from different sources on cultivating Impatiens balsamina L. in municipal solid waste management Полный текст
2018
Chen, Yonggen | Zhou, Chuanbin | Xu, Wanying
At different stages of municipal solid waste management, several technologies such as home composting, industrial composting, and landfill mining could be used to recycle organic matters. Assessing the quality of composted material is crucial for determining where and how for recycling the organic fractions of municipal solid waste (OFMSW). Current studies mainly focused on comparing their biochemical characteristics and environmental impacts; however, comprehensive effects on cultivating plants were rarely compared with composted materials from different sources. Here, the final composting products from home composting (HC), industrial composting (IC), and landfill mining (LM), with different mixing ratios between OFMSW and soil (25, 50, 75, and 100%), were applied for cultivating Impatiens balsamina L. to examine the growing and flowering features under 195 days of observation. We found that all types of composted materials showed positive effects on growth of impatiens; however, their individual profiles were significant different. Generally, compost from HC showed the best comprehensive effects on the plant. Impatiens’ dry weight biomass and maximum number of leaves and flowers of HC were1.5 and 2.8 times, 1.1 and 1.6 times, and 1.8 and 4.2 times than those of IC and LM, respectively. Compost from IC was superior in prolonging leaf-growing phase and increasing photosynthesis pigment contents of impatiens. Although comprehensive effect of fine fraction from landfill mining was much lower than HC and IC compost, it still improved impatiens growth and flowering compared to normal sandy soil. The results suggest that direct comprehensive effect on plants growth, flowering, and physiological influences could be introduced as an indicator when we compare different approach to recycle organics from MSW. Comprehensive effect on plants growth, flowering, and physiological influences could be introduced as a direct indicator for assessing organic waste recycling.
Показать больше [+] Меньше [-]Concentrations of PCDD/Fs in the neighborhood of a hazardous waste incinerator: human health risks Полный текст
2018
Marquès, Montse | Nadal, Martí | Díaz-Ferrero, Jordi | Schuhmacher, Marta | Domingo, José L.
In 1996–1998, a wide surveillance program was initiated in the vicinity of a new hazardous waste incinerator (HWI) placed in Constantí (Catalonia, Spain), which started its regular operations in 1999. The program was aimed at assessing the environmental impact of the facility on the surrounding environment, as well as to evaluate the potential risks for the population living in the neighborhood. Since then, among other measurements, the concentrations of polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) have been periodically determined in soil and herbage samples. This study shows the results, corresponding to the period 2013–2016. Data were compared with those obtained in the baseline survey (1996–1998), as well as with those of the previous survey (2011–2012). The median PCDD/F concentrations in soils were 0.44 and 0.33 ng toxic equivalent (I-TEQ)/kg in 2015 and 2016, respectively, with a significant decrease in relation to the baseline survey, and a non-significant decrease between 2015 and 2016. In turn, PCDD/F levels in vegetation showed some fluctuations over time, being the concentrations of PCDD/Fs in 2013 very similar to those found in 2012 (1.11 and 1.23 ng I-TEQ/kg, respectively). These concentrations notably decreased along the three last campaigns (0.16, 0.23, and 0.17 ng I-TEQ/kg in 2014, 2015, and 2016, respectively). These changes would be more related to a number of environmental factors rather than to a variation of PCDD/F emissions by the HWI. With respect to human health risks, exposure to PCDD/Fs in the area under potential influence of the HWI is not of concern, as the current environmental concentrations of PCDD/Fs do not mean additional carcinogenic or non-carcinogenic risks for the local population.
Показать больше [+] Меньше [-]Contrasting dynamics of polychlorinated biphenyl dissipation and fungal community composition in low and high organic carbon soils with biochar amendment Полный текст
2018
Huang, Shengyan | Shan, Mingjuan | Chen, Junhui | Penttinen, Petri | Qin, Hua
Biochar amendment has been advocated as an effective method to remediate organic pollutant-contaminated soils through adsorption and stimulating microbial degradation. However, such effects can vary depending on soil properties and biochar physiochemical characteristics. The objective of this study was to compare the dynamic variations of polychlorinated biphenyls (PCBs) in low and high soil organic carbon (SOC) soils both amended with biochar and to investigate its linkage with fungal community composition. Two soils having the same texture and soil type but varying in SOC contents were contaminated with PCBs to a final concentration of 60 mg kg⁻¹ and amended with 2% bamboo biochar. Temporal changes of PCB remaining in soils and adsorbed on biochar particles were determined during a 2-month incubation. Diversity and composition of fungal communities in both low and high SOC soils were investigated with Illumina MiSeq sequencing. The results showed that the PCB concentrations in low SOC soil were significantly lower than those in high SOC soil during the incubation. In the low SOC soil, the biochar particle adsorbed higher amounts of PCB, tetra-, and penta-chlorobiphenyls (CBs) than those in high SOC soil, and stimulated the dissipation of di- and tri-CBs. The nonmetric multidimensional scaling profile showed significant (p < 0.05) differences in the fungal community composition between the low and high SOC soils. The relative abundances of Eurotiomycetes were gradually increased, whereas those of Sordariomycetes and Dothideomycetes were decreased with increasing incubation time in the low SOC soils. In contrast, the fungal communities in high SOC soils were relatively stable. The relative abundances of Eurotiomycetes and Sordariomycetes were positively correlated with PCB dissipation in low and high SOC content soils, respectively. Our results suggest that SOC content affects PCB dissipation and fungal community composition in biochar-amended soils, and biochars have a high remediation potential of PCB in soils with low SOC contents.
Показать больше [+] Меньше [-]Comparison of exposure to trace elements through vegetable consumption between a mining area and an agricultural area in central Chile Полный текст
2018
Aguilar, Marcelo | Mondaca, Pedro | Ginocchio, Rosanna | Vidal, Kooichi | Sauvé, Sébastien | Neaman, Alexander
Human exposure to trace elements has been a large concern due to the potential health issues. Accordingly, this study aimed to compare the concentrations of arsenic, copper, and zinc in the edible parts of vegetables grown in a mining-agricultural area and in an exclusively agricultural area and to compare the potential human health risks of consuming vegetables from both areas. The consumption habits of the studied population were extracted from the 2010 National Alimentary Survey of Chile. In most cases, the concentrations of trace elements in the edible tissues of vegetables (lettuce, spinach, garlic, onion, carrot, potato, sweet corn, and tomato) were higher in the mining-agricultural area than those in the control area. This difference was most pronounced for leafy vegetables, with arsenic being the trace element of concern. Specifically, the arsenic concentrations in the edible tissues of lettuce and spinach were 8.2- and 5.4-fold higher, respectively, in the mining-agricultural area than in the control area. Lettuce was the vegetable of concern due to its relatively high consumption and relatively high concentration of trace elements. Nevertheless, there was no health risk associated with vegetable consumption in either the mining area or the control area because none of the HQ values surpassed 1.0.
Показать больше [+] Меньше [-]Modeling the risk of water pollution by pesticides from imbalanced data Полный текст
2018
Trajanov, Aneta | Kuzmanovski, Vladimir | Real, Benoit | Perreau, Jonathan Marks | Džeroski, Sašo | Debeljak, Marko
The pollution of ground and surface waters with pesticides is a serious ecological issue that requires adequate treatment. Most of the existing water pollution models are mechanistic mathematical models. While they have made a significant contribution to understanding the transfer processes, they face the problem of validation because of their complexity, the user subjectivity in their parameterization, and the lack of empirical data for validation. In addition, the data describing water pollution with pesticides are, in most cases, very imbalanced. This is due to strict regulations for pesticide applications, which lead to only a few pollution events. In this study, we propose the use of data mining to build models for assessing the risk of water pollution by pesticides in field-drained outflow water. Unlike the mechanistic models, the models generated by data mining are based on easily obtainable empirical data, while the parameterization of the models is not influenced by the subjectivity of ecological modelers. We used empirical data from field trials at the La Jaillière experimental site in France and applied the random forests algorithm to build predictive models that predict “risky” and “not-risky” pesticide application events. To address the problems of the imbalanced classes in the data, cost-sensitive learning and different measures of predictive performance were used. Despite the high imbalance between risky and not-risky application events, we managed to build predictive models that make reliable predictions. The proposed modeling approach can be easily applied to other ecological modeling problems where we encounter empirical data with highly imbalanced classes.
Показать больше [+] Меньше [-]Ecotoxicological and biochemical mixture effects of an herbicide and a metal at the marine primary producer diatom Thalassiosira weissflogii and the primary consumer copepod Acartia tonsa Полный текст
2018
Filimonova, Valentina | Nys, Charlotte | De Schamphelaere, Karel A. C. | Gonçalves, Fernando | Marques, João C. | Gonçalves, Ana M. M. | De Troch, Marleen
Mixture effects of chemicals and their potential synergistic interactions are of great concern to the public and regulatory authorities worldwide. Intensive agricultural activities are leading to discharges of chemical mixtures to nearby estuarine and marine waters with possible adverse effects on the aquatic communities and for the trophic food web interlinking these communities. Further information about the impacts of these stressors on aquatic organisms is needed. This study addresses ecotoxicological and biochemical effects of single and mixtures of the metal copper and the herbicide Primextra® Gold TZ on the marine diatom Thalassiosira weissflogii and on the estuarine calanoid copepod Acartia tonsa by determining growth rate and survival, respectively, and changes on fatty acid(FA) profiles in both species. Mixture effects on diatom species revealed that copper and Primextra® acted most likely additively with respect to the concentration addition (CA) and independent action (IA) models with model deviation ratios (MDR), 0.752 and 1.063, respectively. For the copepod species, copper and Primextra® were most likely non-interactive with respect to the CA model (MDR = 1.521) but acted most likely synergistically with respect to the IA model (MDR = 2.026). A significant decline in the absolute FA concentration was observed for copepod species after mixture exposure including a considerable decrease of essential FAs that cannot be synthesized de novo by these grazers. We concluded that the mixture effects are more hazardous for primary consumer than for primary producer species in terms of both abundance and biomass quality, suggesting a potential for harmful effects for higher trophic levels and thus a decrease in energy flow through the ecosystem.
Показать больше [+] Меньше [-]Non-essential element concentrations in brown grain rice: Assessment by advanced data mining techniques Полный текст
2018
Villafañe, Roxana | Hidalgo, Melisa | Piccoli, Analía | Marchevsky, Eduardo | Pellerano, Roberto
The concentrations of 17 non-essential elements (Al, As, Ba, Be, Cd, Ce, Cr, Hg, La, Li, Pb, Sb, Sn, Sr, Th, Ti, and Tl) were determined in brown grain rice samples of two varieties: Fortuna and Largo Fino. The samples were collected from the four main producing regions of Corrientes province (Argentina). Quantitative determinations were performed by inductively coupled plasma mass spectrometry (ICP-MS), using a validated method. The contents of As, Be, Cd, Ce, Cr, Hg, Pb, Sb, Sn, Th, and Tl were very low or not detected in most samples. The non-essential element levels detected were in line with studies conducted in rice from different parts of the world. In order to characterize the influence of geographical origin in the samples, the following classification methods were carried out: linear discriminant analysis (LDA), k-nearest neighbors (k-NN), partial least squares discriminant analysis (PLS-DA), support vector machine (SVM) and random forests (RF). The best performance was obtained by using RF (96%) and SVM (96%). The results reported here showed the variation in the non-essential element profiles in rice grain depending on the geographical origin.
Показать больше [+] Меньше [-]Seasonal variations of natural radionuclides, minor and trace elements in lake sediments and water in a lignite mining area of North-Western Greece Полный текст
2018
Noli, Fotini | Tsamos, Panagiotis
The radiological and chemical pollution of a cluster of four lakes in a lignite mining area of North-Western Greece was investigated using a variety of analytical techniques. Alpha spectrometry was applied to measure the activity concentrations of the uranium radioisotopes (U-234, U-235, and U-238) in waters. The mass activities of U-238, Th-232, and K-40 in sediments were measured by high-resolution gamma spectrometry. Furthermore, the determination of the minor and trace elements was carried out by instrumental neutron activation analysis (INAA) in both water and sediments samples, respectively. Pollution levels were also evaluated by calculating enrichment factors (EFs), contamination factors (CFs) and pollution load index (PLI). The data were discussed taking into account several parameters such as the distance from the pollution source, temperature, and location and showed that the environmental impact in this region could not be considered as negligible. The deviation of the isotopic ratio of U-234/U-238 from the equilibrium value indicated waters with intensive dissolution of uranium. The activity values in both waters and sediments found to be low in cool periods and increased in warm periods. Moreover, the concentrations of the elements U, Zn, and Fe were raised in water samples indicating possible pollution as well as the CFs and PLI denoted accumulation in the sediments and moderate to severe contamination for Zn and Cr in some cases.
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