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Correction to: Evaluation of hydrochar efficiency for simultaneous removal of diclofenac and ibuprofen from aqueous system using surface response methodology
2019
Qureshi, Tahira | Memon, Najma | Memon, Saima Q. | Yavuz, Handan | Lachgar, Abdesadek | Denizli, Adil
The original publication of this paper contain typographical mistakes.
Afficher plus [+] Moins [-]Potential of Solanum viarum Dunal in use for phytoremediation of heavy metals to mining areas, southern Brazil
2019
Afonso, Thays França | Demarco, Carolina Faccio | Pieniz, Simone | Camargo, Flávio A. O. | Quadro, Maurízio Silveira | Andreazza, Robson
Mining tailing areas may contain metal minerals such as Cu, Pb, Zn, Cr, and Cd at high concentrations and low nutrients for the growth of plants. This kind of conditions of the area, as well as lack of tailing structure, may limit the development of plants on these areas. Thus, the present study determined the metal, macronutrient, and micronutrient concentrations in the tissues of the roots and shoots of the Solanum viarum Dunal species as well as it evaluated the potential use of the plant for phytoremediation of mining tailing areas contaminated with heavy metals. The macronutrients, micronutrients, and heavy metals in the roots and shoots were determined by the digestion method with nitric and perchloric acid (HNO₃-HClO₄) and quantified by the ICP-OES. In S. viarum, the average concentrations of the metals presented in the dry biomass varied between the shoots and roots, being higher in the roots for metals such as Cu (229 mg kg⁻¹), Zn (232 mg kg⁻¹), Mn (251 mg kg⁻¹), Cr (382 mg kg⁻¹), Ni (178 mg kg⁻¹), Pb (33 mg kg⁻¹), and Ba (1123 mg kg⁻¹). S. viarum indicates the possibility of a potential application in phytoremediation and treatment of areas contaminated with heavy metals.
Afficher plus [+] Moins [-]Quantitative ecotoxicological impacts of sewage treatment plant effluents on plankton productivity and assimilative capacity of rivers
2019
Karrasch, Bernhard | Horovitz, Omer | Norf, Helge | Hillel, Noa | Hadas, Ora | Beeri-Shlevin, Yaron | Laronne, Jonathan B.
Sewage treatment plants are sources of inorganic and organic matter as well as contaminants for the receiving watercourses. We analyzed the ecological consequences of such effluents by following a holistic and synecological ecotoxicological approach based on quantifying extracellular enzyme activities (EEA), primary production and bacterial cell, and biomass production rates. Samples were obtained at three locations at the Rivers Holtemme and Elbe, Germany and Lower Jordan River, Israel and West Bank, as well as from their adjacent sewage treatment plants. Blending river samples with sewage treatment plant effluents mainly resulted in a stimulation of EEAs, which was diminished in blends with 0.2-μm filtered sewage treatment plant effluents. Stimulation for primary production and bacterial cell and biomass production of River Holtemme and Elbe samples was observed, and inhibition of these rates for Lower Jordan River samples probably linked to generally high turbidity. The quantified bacterial biomass versus cell production rates showed almost unbalanced (≫ 1) growth. Very high biomass to cell production ratios were found for sewage and sewage-containing samples, which provides a semi-quantitative indicator function for high quantities of microbial easy utilizable dissolved organic matter as nutrition source. The presented approach enables the simultaneous quantification of inhibitory and stimulating toxic responses as well as supplying ecosystem-based data for policy decision-making, and for direct incorporation in models to derive management and remediation strategies.
Afficher plus [+] Moins [-]Construction of rGO wrapping Cu2O/ZnO heterostructure photocatalyst for PNP and PAM degradation
2019
Liu, Fang | Che, Yangli | Chai, Qingwen | Zhao, Mengfei | Lv, Yan | Sun, Hui | Wang, Yongqiang | Sun, Juan | Zhao, Chaocheng
Copper and zinc composite oxides (Cu₂O/ZnO) were synthesized by an impregnation-reduction-air oxidation method. A series of Cu₂O/ZnO/rGO ternary composites were prepared by coupling with graphene oxide (GO) with different mass fractions in a solvothermal reaction system. The microscopic morphology, crystal structure, and optical characteristics of the photocatalysts were characterized. The degradation of p-Nitrophenol (PNP) and polyacrylamide (PAM) by photocatalytic materials under simulated solar irradiation were studied, and the degradation kinetics were also investigated. The results showed that cubic Cu₂O was modified by ZnO nanorods and distributed on rGO nanosheets. The ternary Cu₂O/ZnO/rGO nanocomposites have stronger simulated solar absorption ability and higher photodegradation efficiency than pure ZnO and binary Cu₂O/ZnO nanocomposites. When the amount of Cu₂O/ZnO/rGO-10 was 0.3 g L⁻¹, the degradation rate of 10 mg L⁻¹ PNP reached 98% at 90 min and 99.6% of 100 mg L⁻¹ PAM at 30 min. The photocatalytic degradation processes of PNP and PAM all followed the pseudo-first-order kinetic model. Free radical trapping experiments showed that superoxide radicals were the main active substances to improve photocatalytic efficiency. In addition, after four recycles, the catalytic efficiency of Cu₂O/ZnO/rGO-10 was still over 90%. It showed that Cu₂O/ZnO/rGO-10 was a promising catalyst for wastewater treatment because of its good photostability and reusability.
Afficher plus [+] Moins [-]Seasonal dynamics of phytoplankton in response to environmental variables in contrasting coastal ecosystems
2019
Srichandan, Suchismita | Baliarsingh, Sanjiba Kumar | Prakash, Satya | Lotliker, Aneesh A. | Parida, Chandanlal | Sahu, Kali Charan
Seasonal distribution of phytoplankton community and size structure was assessed in three different tropical ecosystems of the western Bay of Bengal viz. estuary (Mahanadi), lagoon (Chilika), and coastal waters (off Gopalpur) in response to ambient hydrobiology. Salinity regimes differentiated the study regions as contrasting ecosystems irrespective of seasons (pre-monsoon, monsoon, post-monsoon). Taxonomic account revealed a total no of 175, 65, and 101 phytoplankton species in the estuary, lagoon, and coastal waters, respectively. Prevalence of marine, brackish, and fresh water types in the coastal waters, lagoon, and estuary, respectively, characterized the contrasting nature of the study regions in hosting the phytoplankton community. In general, phytoplankton abundance was observed in increasing order of coastal waters > estuary > lagoon during post-monsoon and pre-monsoon, while lagoon > coastal waters > estuary during monsoon. Bacillariophyta dominated the phytoplankton community in the estuary and coastal waters during all the seasons. In contrast, the lagoon exhibited a diverse array of phytoplankton group such as cyanophyta, dinophyta, and bacillariophyta during monsoon, post-monsoon, and pre-monsoon, respectively. Over the seasons, microphytoplankton emerged as the dominant phytoplankton size class in the coastal waters. Diversely, nanophytoplankton contributed to major fraction of chlorophyll-a concentration in the estuary and lagoon. Interestingly, pre-monsoon dinophyta bloom (causative species: Noctiluca scintillans with cell density 9 × 10⁴ cells·l⁻¹) and monsoon bacillariophyta bloom (causative species: Asterionellopsis glacialis 5.02 × 10⁴ cells·l⁻¹) resulted decline in species diversity. Multivariate statistical analysis deciphered salinity as a major environmental player in determining the distribution, diversity, and composition of phytoplankton communities in the three contrasting environments. Trophic state indices signified the lagoon and estuary as hypereutrophic during all season. The coastal water was marked as highly eutrophic through trophic state index during monsoon and pre-monsoon.
Afficher plus [+] Moins [-]Evaluation of emerging biomarkers of renal damage and exposure to aflatoxin-B1 in Mexican indigenous women: a pilot study
2019
Díaz de León Martínez, Lorena | Díaz-Barriga, Fernando | Barbier, Olivier | Ortíz, Dora Linda Guzmán | Ortega-Romero, Manolo | Pérez Vázquez, Francisco | Flores Ramírez, Rogelio
Aflatoxins (AFs) are mycotoxins produced by Aspergillus parasiticus and Aspergillus flavus which frequently contaminate maize. These compounds are considered toxic, especially AFB₁ which has been classified as a human carcinogen, due to its relationship with the generation of hepatocellular carcinoma. Studies in vivo, in animal models, prove that chronic consumption of AFB₁ has an association with renal adverse effects, but evidence in humans is scarce. Therefore, the main objective of this research was to conduct a pilot study to evaluate the correlation between exposure to AFB₁ and early-stage renal damage in indigenous women of San Luis Potosí, Mexico. Exposure to AFB₁ was measured through the biomarker AFB₁-lysine and renal damage through kidney injury molecule-1 (KIM-1), neutrophil gelatinase-associated lipocalin (NGAL), and cystatin-C (Cys-C). AFB₁-Lys was measured by HPLC-FLD. The method was validated with a correlation coefficient of 0.99 and limit of detection and quantification of 3.5 and 4.7 pg mL⁻¹, respectively. Levels of NGAL, KIM-1, and Cys-C were determined (median (P25–P75), 5.96 (3.16–15.91), 0.137 (0.137–0.281), and 18.49 (5.76–29.57) ng mL⁻¹, respectively). Additionally, glomerular filtration rate (GFR) (83.3 (59.8–107.4) mL/min/1.73 m²) and serum creatinine (SCr) (0.88 (0.72–1.22) mg dL⁻¹) were obtained. The median concentrations for AFB₁-Lys were 2.08 (1.89–5.8) pg mg⁻¹ of albumin. Statistically significant correlations between AFB₁-Lys/KIM-1 (Rho = 0.498, p = 0.007) and AFB₁/Cys-C (Rho = 0.431, p = 0.014) were found. Our results indicate that women are exposed to AFB₁, due to the fact that the AFB₁-Lys biomarker was found in a high percentage of the study population (83%). In addition, the results of exposure to AFB₁ show a strong significant correlation between KIM-1 and Cys-C that may indicate the toxic renal effect. These results are alarming because of the high toxicity of this compound and require adequate intervention to reduce AFB₁ exposure in these populations.
Afficher plus [+] Moins [-]Some toxic metals (Al, As, Mo, Hg) from cow’s milk raised in a possibly contaminated area by different sources
2019
González-Montaña, José-Ramiro | Senís, Enrique | Alonso, Angel-Javier | Alonso, Marta-Elena | Alonso, María-Pilar | Domínguez, Juan-Carlos
Milk can be considered as an indicator of the degree of environmental contamination of the place where it is produced and this is especially important when assessing its content in toxic metals. Therefore, 36 bovine milk samples from 7 farms with a semi-extensive grazing system were analysed, located in Asturias (Spain), in an area with high probability of being highly contaminated due to a mining zone, with important industrial activity and near high-density highway traffic. The samples were lyophilised to achieve total dehydration, further analysed using inductively coupled plasma mass spectrometry (ICP-MS). The metals titrated were aluminium (Al), arsenic (As), molybdenum (Mo) and mercury (Hg) in the lyophilised samples and subsequently extrapolated their values to whole milk. All samples analysed showed levels of Al and Mo above the limit of detection, with mean values of Al of 140.89 ± 157.07 in liquid milk and 1065.76 ± 1073.45 in lyophilised milk and Mo of 20.72 ± 14.61 μg/kg and 152.26 ± 96.82 μg/kg in whole and lyophilised milk. Only As was detected in four samples with mean values of 18.45 ± 6.89 and 166.45 ± 42.30 μg/kg in liquid and lyophilised milk, respectively, and no Hg was found in any of them. In no case do the values found indicate a significant hazard to the population and are in agreement with those found in other investigations. Although the various anthropogenic activities of the area (industrial, mining, traffic density) could, a priori, indicate a possibly contaminated area.
Afficher plus [+] Moins [-]Zinc-lysine prevents chromium-induced morphological, photosynthetic, and oxidative alterations in spinach irrigated with tannery wastewater
2019
Zaheer, Ihsan Elahi | Ali, Shafaqat | Rizwan, Muhammad | Bareen, Firdaus-e- | Abbas, Zohaib | Bukhari, Syed Asad Hussain | Wijaya, Leonard | Alyemeni, Mohammed Nasser | Ahmad, Parvaiz
Anthropogenic activities have resulted in severe environmental degradation. Untreated wastewater from tanneries is hazardous to all kinds of life on earth. Effluent from tanning industries, containing large amount of Cr, is used to irrigate the crops in Pakistan. The current experiment was carried out to study the effects of tannery wastewater on spinach and the role of lysine-Zn in mitigating the severity of stress. The plants were grown in soil and the following treatments were used: irrigation with 0%, 33%, 66%, and 100% wastewater (ww) along with two doses (0 mM, 10 mM) of Zn-lysine. Foliar application of zinc-lysine enhanced the plant growth, biomass, Zn contents, photosynthesis, and enzyme activities in different tissues of plant. Zinc-lysine (10 mM) considerably decreased the Cr content in roots and shoots, along with ameliorating the oxidative stress by enhancing the activities of antioxidant enzymes in plants. Addition of Zn-lys (10 mM) improved the plant height by 19%, root length by 57%, leaf dry weight by 19%, and root dry weight by33% under 100% Cr treatment. Zn-lys significantly reduces the oxidative stress and concentration of Cr as compared with the Cr treatments alone. Application of Zn-lys (10 mM) reduced the Cr contents in roots by 27 and 22 under 33 and 66% Cr treatment, respectively. Taken together, Zn-lys chelates efficiently ameliorated the toxic effects of chromium. Zn-lysine has the extravagant potential of mitigating the heavy metal toxicity without harming the normal growth and development of the plants.
Afficher plus [+] Moins [-]The economic growth/development and environmental degradation: evidence from the US state-level EKC hypothesis
2019
Isik, Cem | Ongan, Serdar | Özdemir, Dilek
This study investigates the validity of the EKC (environmental Kuznets curve) hypothesis for the 50 US states and a Federal District (Washington, D.C.). To this aim, the common correlated effects (CCE) and the augmented mean group (AMG) estimation procedures are applied between 1980 and 2015. While the CCE estimation does not support EKC hypothesis, the AMG does. The empirical findings of the AMG estimation indicate that only 14 states verify the EKC hypothesis. Additionally, the expected negative impacts of fossil energy consumption on the environment (CO₂ emissions) are strongly detected in all states except Texas. However, the expected positive impacts of renewable energy consumption on the CO₂ emissions are detected only in 13 states. Furthermore, the expected negative impacts of the population are not detected in some mostly populated states like New York, Texas, and Ohio. The overall findings of this study may help the US state-level policy makers in two ways: first, to understand whether their economic growths are sustainable (eco-friendly); second, to see how their fossil and renewable energy consumptions affect their environments and to review their energy policies.
Afficher plus [+] Moins [-]An evaluation of dietary selenium nanoparticles for red sea bream (Pagrus major) aquaculture: growth, tissue bioaccumulation, and antioxidative responses
2019
Dawood, Mahmoud A. O. | Koshio, Shunsuke | Zaineldin, Amr I. | Van Doan, Hien | Ahmed, Hamada A. | Elsabagh, Mabrouk | Abdel-Daim, Mohamed M.
Selenium nanoparticles (Se-NPs) were added at 0, 0.5, 1, and 2 mg per kg diet to assess its effects on the performance, Se bioaccumulation, blood health, and antioxidant status of red sea bream. After 45 days, Se-NPs positively impacted the growth and feed efficiency of red sea bream especially by 1 mg per kg diet. No significant (P > 0.05) changes in survival and somatic indices were noticed among groups. Dietary Se-NPs significantly (P < 0.05) increased the protein, lipid, and Se contents in the whole body, muscle, and liver tissues, whereas decreasing the whole-body moisture content of treated groups compared with the Se-NP-free group. Using of Se-NPs at 2 mg per kg diet resulted in the highest Se content in the complete body, muscle, and liver. Significantly enhanced intestine protease activity and hematocrit levels accompanied with low cholesterol and triglyceride were observed in fish fed Se-NP-enriched diets. Fish fed on Se-NPs at 0.5, 1, and 2 mg Se-NPs per kg diet exhibited significantly higher values of biological antioxidant potential than the control group (P < 0.05). Therefore, the obtained results recommends adding 1 mg Se-NPs per kg diet to improve the growth, feed efficiency, blood health, and antioxidant defense system of red sea bream.
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