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Assessment of the impact of heavy metals in sediments along the Spanish Mediterranean coastline: pollution indices Texte intégral
2019
Paches, Maria | Martínez-Guijarro, Remedios | Aguado, Daniel | Ferrer, José
A comprehensive study was carried out to evaluate the occurrence, significance of concentrations and spatial distribution of heavy metals (Cr, Cd, Ni, Cu, Pb, Hg, Zn and As) in sediments along the Valencia coastline (Spain). The sampling campaign covered 476 km of the coastline in a 4-year period. The highest concentrations of metals in the sediments were mainly Cr, Ni, Zn and Cd (up to 28.93 mg Cr kg⁻¹ dw, 15.80 mg Ni kg⁻¹ dw, 57.13 mg Zn kg⁻¹ dw and 0.293 mg Cd kg⁻¹ dw), obtained in the northern areas, some central areas and in an isolated area on the southern coastline. The Sediment Quality Guidelines applied reveal that for all metals studied, none of them reached, or exceed, the “effects of median range” or the “probable effect level”. The pollution index reveals that 75% of the stretch coastline has a low priority risk level and the rest “medium-low priority risk level”. And, lastly, Potential Ecological Risk Index shows that all but one zone have low ecological risk.
Afficher plus [+] Moins [-]Long-term responses of Scots pine (Pinus sylvestris L.) and European beech (Fagus sylvatica L.) to the contamination of light soils with diesel oil Texte intégral
2019
Bęś, Agnieszka | Warmiński, Kazimierz | Adomas, Barbara
Research into trees plays a very important role in evaluations of soil contamination with diesel oil. Trees are ideal for reclaiming contaminated soils because their large biomass renders them more resistant to higher concentrations of pollutants. In the literature, there is a general scarcity of long-term studies performed on trees, in particular European beeches. The aim of this study was to evaluate the responses of Scots pines and European beeches grown for 8 years on soil contaminated with diesel oil. Selected morphological and physiological parameters of trees were analyzed. The biomass yield of Scots pines was not significantly correlated with increasing concentrations of diesel oil, but it was more than 700% higher than in European beeches. Scots pines were taller and had a larger stem diameter than European beeches during the 8-year study. The diameter of trees grown on the most contaminated soil was reduced 1.5-fold in Scots pines and more than twofold in European beeches. The length of Scots pine needles from the most contaminated treatment decreased by 50% relative to control needles. The shortest needles were heaviest. The fluctuating asymmetry (FA) of needle length was highest in Scots pines grown on the most contaminated soil, whereas the reverse was noted in the FA of needle weight. Diesel oil decreased the concentrations of chlorophylls a and b, total chlorophyll, and carotenoids. The Fv/Fm ratio of needles and leaves was influenced by the tested concentrations of diesel oil. The results of the study indicate that the Scots pine better adapts (grows more rapidly and produces higher biomass) to long-term soil contamination with diesel oil than the European beech. In European beeches, growth inhibition and leaf discoloration (a decrease in chlorophyll content) were observed already after the first year of the experiment, which indicates that 1-year-old seedlings of European beech are robust bioindicators of soil contamination with diesel oil.
Afficher plus [+] Moins [-]Prediction of O3 in the respiratory system of children using the artificial neural network model and with selection of input based on gamma test, Ahvaz, Iran Texte intégral
2019
Ghaedrahmat, Zeinab | Vosoughi, Mehdi | Tahmasebi Birgani, Yaser | Neisi, Abdolkazem | Goudarzi, Gholamreza | Takdastan, Afshin
In recent years, concerns over the issue of air pollution have increased as one of the significant environmental and health problems. Air pollutants can be toxic or harmful to the life of plants, animals, and humans. Contrast to primary pollutants, ozone is a secondary pollutant that is produced by the reaction between primary precursors in the atmosphere. The average of air pollutant data was compiled for the purpose of analyzing their correlation with the pulmonary function of students and the FENO biomarker from the air pollutants of the Environmental Protection Agency. According to the average of 3 days, the concentration of ozone in the (S₃) region was higher than the other regions, and this level was significantly different from the ANOVA test (p < 0.05). The results of artificial neural network modeling for three particular combinations in the cold season, two hidden layers with 9 and 12 neurons, with R² = 0.859 and in the warm season, layer with 13 neurons, with R² = 0.74, showed the best performance.
Afficher plus [+] Moins [-]A non-linear assessment of the urbanization and climate change nexus: the African context Texte intégral
2019
Tiba, Sofien
The climate change issue becomes more challenging with the increasing pace of urbanization in Africa. For this purpose, we attempt to examine the relationship urbanization and CO₂ emissions by applying the panel smooth transition regression model for 47 African countries during the spanning time 1990–2014. Our results reveal that the nexus between urbanization and CO₂ emissions is non-linear. Our highlights recorded a monotonic nexus confirming the existence of the EKC hypothesis for the urbanization. In addition, our empirical results determine the threshold of the transition which takes the value of 42.01. Moreover, the estimated slope parameter implies that the nexus between urbanization and CO₂ emissions smoothly switches from one regime to another regime but relatively rapid. Hence, it is extremely important to understand this nexus to take seriously climate change vulnerabilities. Indeed, the African economies are invited to establish efficiently the low-carbon and reduce the spatial heterogeneity to generate the green development path and provide effective structures for a platform for sustainable cities.
Afficher plus [+] Moins [-]Effect of phosphogypsum addition in the composting process on the physico-chemical proprieties and the microbial diversity of the resulting compost tea Texte intégral
2019
Samet, Mariem | Karray, Fatma | Mhiri, Najla | Kamoun, Lotfi | Sayadi, Sami | Gargouri-Bouzid, Radhia
Phosphoric acid production and olive oil production are among the most important economical sectors in Tunisia. However, they generate huge amounts of wastes (phosphogypsum, olive mill waste water, and olive pomace). In a previous study, we used phosphogypsum (PG), in co-composting with organic wastes. Three composts were produced; their PG content was of 0 (AT), 10 (A10), and 30% (A30). In the present study, we focused on their derived compost teas. The physico-chemical characterization of the different compost teas showed that those from A10 and A30 composts presented higher P and Ca contents than that from control one (AT). The microbial characterization using DGGE showed a noticeable microbial diversity in the different compost teas and that the addition of 10% and 30% PG in the compost had different effects on the compost tea microbial diversity. The identification results showed that the addition of 10 and 30% of PG did not affect the presence of PGPR (plant growth-promoting rhizobacteria) and fungal soil antagonists in the compost teas. Two PGPRs were isolated from AT and A30 compost teas, and their effect on the growth of potato plants in vitro was evaluated.
Afficher plus [+] Moins [-]A visualized investigation on the intellectual structure and evolution of waste printed circuit board research during 2000–2016 Texte intégral
2019
Yang, Lie | He, Liuyang | Ma, Yongfei | Wu, Li | Zhang, Zulin
Waste printed circuit boards (WPCBs) containing various metals and hazardous materials are considered as a secondary resource and an environmental pollution source. A systematic overview of WPCB study was conducted by using CiteSpace. The relevant knowledge of 242 documents was collected from SCI-Expanded database (SCIE) and saved as txt files. A 556-node and 636-link network and 17 clusters were obtained. Based on co-citation network, nonmetallic material treatment and recycling, metal recovery, pyrolysis treatment, and new technology development were successively the most attractive fields in the study period. Timeline pattern showed that mechanical processing attracted great attention in the initial period and profitability assessment was the latest hot spot in WPCB study. The results could provide a reference for future work in WPCB field.
Afficher plus [+] Moins [-]Removal of phenanthrene and pyrene from contaminated sandy soil using hydrogen peroxide oxidation catalyzed by basic oxygen furnace slag Texte intégral
2019
Hu, Enzhu | He, Zan | Nan, Xiangli | Yuan, Zaijian | Li, Xiaojun
Soil contamination with polycyclic aromatic hydrocarbons (PAHs) is a serious problem in Northeast China, especially in the steel industrial area. The objective of this study was to evaluate the feasibility of using basic oxygen furnace (BOF) slag to activate the Fenton-like remediation of PAH-contaminated soil to achieve the objectives of “waste control by waste” and “resource recycling” in Chinese steel industry. The effects of BOF slag dosages, H₂O₂ concentrations, and exothermicity-driven evaporation were evaluated with respect to the removal efficiencies of phenanthrene (Phe) and pyrene (Pyr). Results indicated that PAH oxidation was proportional to the BOF slag dosages and was increased exponentially with H₂O₂ concentrations. Evaporation due to increasing temperature caused by exothermic reaction played an important role in total soil PAH losses. The sequential Fenton-like oxidation with a 3-times application of 15% H₂O₂ and the same BOF slag repeatedly used were able to remove 65.87% of Phe and 58.33% of Pyr, respectively. Soluble iron oxides containing in BOF slag were reduced, while amorphous iron oxide concentration remained stable during the repeated Fenton-like process. Column study mimics real field applications showing high removal efficiencies of Phe (36.05–83.20%) and Pyr (21.79–68.06%) in 30-cm depth of soil profile. The tests on soluble heavy metal concentrations after the reactions with high slag dosage or high H₂O₂ concentration confirmed that BOF slag would not cause heavy metal contamination. Consequently, BOF slag may provide an efficient way for enhancing the Fenton-like based remediation of heavily PAH-polluted soil with little risk on collateral heavy metal contamination. However, an external gas collection and purification equipment would be essential to eliminate the evaporated PAHs.
Afficher plus [+] Moins [-]Metabonomic analysis of the hepatic injury suffer from hexavalent chromium poisoning in broilers Texte intégral
2019
Zhao, Yali | Zhang, Hui | Wu, Xiaoxing | Zhang, Tianguang | Shen, Ke | Li, Lei | Peng, Yuxuan | Meman, K̲h̲ālid Maḥmūd | Zhou, Donghai
Chromium is used in daily life and has a wide range of functions. It plays an important role in protein synthesis and carbohydrate and lipid metabolism. Chromium is found in trivalent Cr(III) and hexavalent Cr(VI) form; Cr(III) is relatively stable and intimately participates with many phenomena of metabolisms. Whereas, Cr(VI) is toxic, which results in growth inhibition and leading to changes in components of antioxidant systems as well as secondary metabolites. However, the molecular mechanism that is involved in Cr (VI)-induced hepatotoxicity is still unclear. For this purpose, 40 chickens were randomly assigned into two groups: the normal group (feeding the basic diet and clear water), the chromium group (16%LD₅₀, 74.24 mg/kg/day K₂Cr₂O₇). The samples were subjected to pathological examination and UHPLC-QE-MS non-target metabolomics method for metabolomics analysis of broiler liver using principal component analysis (PCA) and partial least squares discriminant analysis (OPLS-DA). The central venous cells of the broiler liver in the chromium poisoning group showed turbidity and flaky necrosis, nuclear condensation, nuclear rupture, and even nuclear dissolution. The differential metabolite analysis between the chromium poisoning and the control group showed that 32 differential metabolites were upregulated and 15 were downregulated in positive ion mode. Whereas,17 differential metabolites were downregulated, and 35 were downregulated in negative ion mode (P ≤ 0.05). The potential marker substances are oleic acidamide, farnesylacetone, betaine, taurine, choline, and galactinol. Additionally, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways showed that the lipid metabolism, carbohydrate metabolism, nucleotide metabolism, amino acid metabolism, energy metabolism, membrane transport, digestive system, and nervous system were the most important metabolic pathways in the liver. This study provides a theoretical basis for the future understanding of the pathogenesis of chromium poisoning and a new insight of the subsequent molecular mechanism of chromium hepatotoxicity.
Afficher plus [+] Moins [-]Determination of polycyclic aromatic hydrocarbons (PAHs) and other organic pollutants in freshwaters on the western shore of Admiralty Bay (King George Island, Maritime Antarctica) Texte intégral
2019
Szopińska, Małgorzata | Szumińska, Danuta | Bialik, Robert Józef | Dymerski, Tomasz | Rosenberg, Erwin | Polkowska, Żaneta
Determination of polycyclic aromatic hydrocarbons (PAHs) and other organic pollutants in freshwaters on the western shore of Admiralty Bay (King George Island, Maritime Antarctica) Texte intégral
2019
Szopińska, Małgorzata | Szumińska, Danuta | Bialik, Robert Józef | Dymerski, Tomasz | Rosenberg, Erwin | Polkowska, Żaneta
Organic contamination in freshwater samples has never been investigated at the western shore of Admiralty Bay. Therefore, the presence of polycyclic aromatic hydrocarbons (PAHs) in five different sites distributed along a shore running from the Arctowski Station to the Baranowski Glacier was studied. Moreover, organic compounds such as n-alkanes, toluene and ethylbenzene were also noted. Increased ΣPAHs in late Austral summer 2016 are the result of long-range atmospheric transport of air masses from South America, confirmed by 10-day backward air mass trajectories analysis. The presence of n-alkanes and other hydrocarbons, as well as the evaluation of PAH indices (e.g. ΣLMW/ΣHMW* > 1), shows the use of fuel and indicate local human activity. As a final conclusion, our analysis indicates a mixed origin of PAHs (global and local). The presence of PAHs and other hydrocarbons in the water environment may constitute a potentially negative effect on the Antarctic ecosystem and it should be investigated in detail during further research (//*ΣLMW—sum of low molecular weight PAHs (two- and three-ring PAHs); ΣHMW—sum of high molecular weight PAHs (four- and five-ring PAHs)//). Graphical abstract
Afficher plus [+] Moins [-]Determination of polycyclic aromatic hydrocarbons (PAHs) and other organic pollutants in freshwaters on the western shore of Admiralty Bay (King George Island, Maritime Antarctica)
Fate of Lu(III) sorbed on 2-line ferrihydrite at pH 5.7 and aged for 12 years at room temperature. I: insights from ICP-OES, XRD, ESEM, AsFlFFF/ICP-MS, and EXAFS spectroscopy Texte intégral
2019
Finck, Nicolas | Bouby, Muriel | Dardenne, Kathy
Two-line ferrihydrite (2LFh) was aged for 12 years under ambient conditions and sheltered from light in the presence of Lu(III) used as surrogate for trivalent actinides. 2LFh aging produced hematite rhombohedra with overgrown acicular goethite particles. Analysis of the homogeneous suspension by asymmetrical flow field-flow fractionation (AsFlFFF) coupled to ICP-MS indicated that particles have a mean hydrodynamic diameter of about 140 nm and the strong correlation of the Fe and Lu fractograms hinted at a structural association of the lanthanide with the solid phase(s). Unfortunately, recoveries were low and thus results cannot be considered representative of the whole sample. The suspension was centrifuged and X-ray absorption spectroscopy (XAS) at the Lu L₃-edge on the settled particles indicated that Lu(III) is sixfold coordinated by oxygen atoms, pointing to a retention by structural incorporation within particles. This result is consistent with AsFlFFF results on the same suspension without centrifugation. The detection of next nearest Fe and O atoms were consistent with the structure of goethite, ruling out incorporation within hematite. After centrifugation of the suspension, only nanoparticulate needle-like particles, very likely goethite, could be detected in the supernatant by ESEM. AsFlFFF data of the supernatant were comparable to that obtained for the homogeneous suspension, whereas XAS indicated that Lu(III) is predominantly present as dissolved species in the supernatant. Results from both techniques can be interpreted as a major fraction of Lu present as aqueous ions and a minor fraction as structurally incorporated. Findings from this study are corroborated by STEM-HAADF data and results from DFT calculations in a companion paper.
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