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Could a harmonized tiered approach assess dispersant toxicity in Italy and France? Texte intégral
2020
In recent years, EU countries have recognized national policies to authorize dispersant use to mitigate the petroleum hydrocarbon contamination in case of unintentional oil spills at sea. A harmonization of dispersant approval procedures is needed because the application of different methodologies agrees on dissimilar toxic responses for the same dispersant in different European countries. Actually, different dispersant approval procedures are applied in France and Italy with one French mandatory toxicity test and three Italian bioassays accompanied with different criteria of toxicity classification. In this paper, a harmonized tiered approach is proposed to address the dispersant ecotoxicological assessment in these two nations. Our approach, applicable at the European level, introduces two mandatory tests (algal growth inhibition test and mortality test with crustaceans) and one discretionary test (fish mortality test), by reducing use of vertebrates as much as possible in accordance with humane principles and animal welfare.
Afficher plus [+] Moins [-]Investigation on thermodynamic performance analysis and environmental effects of various new refrigerants used in air conditioners Texte intégral
2020
Shaik, Sharmas Vali | Shaik, Saboor | Gorantla, Kirankumar | Mahapatra, Debasish | Setty, Ashok BabuTalanki Puttaranga
The main aim of this present investigation is to evaluate performance and environmental impact analysis of various novel mixture refrigerants as R22 replacements theoretically. Refrigerants with lower global warming potential (GWP) can be adequate for bringing down emissions which are concerned for air conditioners. In this investigation, twenty-seven refrigerants were developed at several compositions. Important studies such as computation of CO₂ emissions using total equivalent warming impact (TEWI), toxicity and flammability analysis of various considered refrigerants were also carried out in this investigation. Performance analysis of refrigerants was conducted under different operating conditions. Results showed that the energy efficiency ratios (EERs) of refrigerants such as R1270, RM30 (R152a/R1270/RE170 of 25/71/4 by mass percentage) and RM50 (R152a/R1270/RE170 of 10/85/5 by mass percentage) were closer to that of R22 and they are relatively lower than R22 by 0.95%, 1.34% and 1.80%, respectively. Toxicity investigation exhibited that all the refrigerants studied were classified into nontoxic category (A) whereas flammability investigation revealed that all the novel refrigerant mixtures (RM10 to RM50) were classified into flammable category (A3). CO₂ emissions (TEWI) released from air conditioner working with R1270, RM30 and RM50 were 7.41%, 6.85% and 6.51%, respectively, lower than that of R22. In terms of several thermodynamic aspects, the performance of refrigerants such as R1270, RM30 and RM50 were superior to those of R22 and its various considered alternatives working under different operating conditions, although their EERs are fairly lower than R22 and hence, these refrigerants could be considered suitable environment-friendly alternatives to R22 used in air conditioners. The present study gives essential information and a road map towards the development of low GWP R22 alternative refrigerant blends from the viewpoint of toxicity, flammability, performance aspects, environmental and safety aspects, respectively.
Afficher plus [+] Moins [-]Occurrence of microplastics in pellets from the common kingfisher (Alcedo atthis) along the Ticino River, North Italy Texte intégral
2020
Winkler, Anna | Nessi, Alessandro | Antonioli, Diego | Laus, Michele | Santo, Nadia | Parolini, Marco | Tremolada, Paolo
Previous research has reported avian plastic ingestion in marine bird species. Yet, while research attention on plastic pollution is shifting from marine to freshwater ecosystems, very few information on plastic ingestion is available for freshwater birds. Here, we examined the presence of microplastic in regurgitated pellets of the common kingfisher (Alcedo atthis) collected along the Ticino River (North Italy). In total, 133 kingfisher’s pellets were examined between March and October 2019 from 54 transects along the river. Plastic elements were detected and identified by visual inspection followed by μ-FTIR and SEM-EDS. Overall, we found 12 (micro)plastics from at least three different polymers in 7.5% of the pellets. This study provides the first report of plastic uptake of this bird species. It highlights the importance of spectroscopic techniques in plastic monitoring studies in order to avoid misidentification of items found. Documenting the presence of plastic ingestion by top carnivores such as fish-eating birds is necessary to understand the pervasiveness and impact of (micro)plastic pollution in food webs of freshwater ecosystems.
Afficher plus [+] Moins [-]Metal concentration and health risk assessment of fifteen wild mushrooms collected from the Ankara University Campus (Turkey) Texte intégral
2020
Sarikurkcu, Cengiz | Sarikurkcu, Rifat Tayyib | Akata, Ilgaz | Tepe, Bektas
The aim of this study is to analyze Fe, Mn, Cu, Zn, Co, Cd, Pb, and Ni contents of Cyclocybe cylindracea, Armillaria mellea, Bjerkandera adusta, Rheubarbariboletus armeniacus, Coprinellus disseminatus, C. micaceus, C. comatus, Inonotus hispidus, Lepista nuda, Leucoagaricus leucothites, Pleurotus ostreatus, Cerioporus squamosus, Schizophyllum commune, Scleroderma verrucosum, and Trametes trogii collected from the Ankara University Besevler 10th Year Campus (Turkey), an area where human settlement and traffic are intense. In addition to the elemental analysis, the daily intake of metal (DIM) and health risk index (HRI) values of the edible ones were also calculated. Fe, Mn, Cu, Zn, Co, Cd, Pb, and Ni concentrations of the samples were found to be 112.0–5079.0, 3.0–124.0, 4.0–77.0, 2.0–196.0, 0.18–2.98, 0.18–5.3, 0.04–10.98, and 0.22–8.23 mg/kg dry weight, respectively. As a result of DIM and HRI analysis, C. cylindracea, L. nuda, and C. squamosus were found to be within the reference dose limits determined by competent authorities and can be safely consumed in terms of all metals studied. However, the Cd, Co, and Fe contents of C. micaceus were found to be above 1.0 (1.06, 4.25, and 7.06, respectively). In addition, it has been found that A. mellea, R. armeniacus, C. comatus, L. leucothites, and P. ostreatus are toxic in terms of Cd/Co, Fe/Pb, Co/Fe, Cd, and Fe contents, respectively. As the area in question is a traffic intensive area, it has been concluded that the emissions of the vehicles should be controlled in terms of legal limits and that the consumption of some mushrooms in this region should not be preferred until necessary measures are taken.
Afficher plus [+] Moins [-]The long-run and short-run influence of environmental pollution, energy consumption, and economic activities on health quality in emerging countries Texte intégral
2020
Anser, Muhammad Khalid | Hanif, Imran | Vo, Xuan Vinh | Alharthi, Majed
This study investigates the effect of energy utilization, greenhouses gasses emissions, and economic activities on health risks such as mortality rate and incidence of respiratory diseases in emerging Asian economies. The study analyzes a panel data from 1995 to 2018 to examine the long-run and short-run influence of environmental pollution on health issues. The empirical findings highlight that greenhouse gasses emissions, fossil fuel consumption, and natural resources depletion in the region are key factors to increasing health risks in the long-run period, while the use of clean energy and improvement in per capita economic growth is helping to improve the health status of the households. In a short period, greenhouse gasses emission is the only significant factor responsible for the high mortality rate and occurrence of respiratory diseases in the emerging economies of Asia. According to the results, there is a need for government intervention programs to rescue the region from the negative effects of environmental pollution and the utilization of nonrenewable energy. In emerging Asian countries, the combustion of fossil fuels, environmental pollution, and limited access to clean energy are such factors responsible for high mortality rate and stimulating incidence of respiratory diseases in the individuals. The study suggests that alternative green energy can prove helpful to control greenhouse gasses emissions and to control health issues by improving environmental quality. The study further suggests that the use of clean energy from water, wind, and sunlight may prove helpful to meet the energy requirement at the domestic level and improve the health status of the individuals by reducing the incidence of respiratory diseases in emerging countries of Asia.
Afficher plus [+] Moins [-]Occurrence of anticancer drugs in the aquatic environment: a systematic review Texte intégral
2020
Nassour, Carla | Barton, Stephen J. | Nabhani-Gebara, Shereen | Saab, Yolande | Barker, James
Water contamination with pharmaceutical products is a well-studied problem. Numerous studies have demonstrated the presence of anticancer drugs in different water resources that failed to be eliminated by conventional wastewater treatment plants. The purpose of this report was to conduct a systematic review of anticancer drugs in the aquatic environment. The methodology adopted was carried out in compliance with the PRISMA guidelines. From the 75 studies that met the specific requirements for inclusion, data extracted showed that the most common anticancer drugs studied are cyclophosphamide, tamoxifen, ifosfamide and methotrexate with concentrations measured ranging between 0.01 and 86,200 ng/L. There was significant variation in the methodologies employed due to lack of available guidelines to address sampling techniques, seasonal variability and analytical strategy. The most routinely used technique for quantitative determination was found to be solid-phase extraction followed by LC-MS analysis. The lowest reported recovery percentage was 11%, and the highest limit of detection was 1700 ng/L. This indicated the inadequacy of some methods to analyse anticancer drugs and the failure to obtain reliable results. The significant heterogeneity within methodologies made it difficult to compare results and draw conclusions, nevertheless, this study aids in the extrapolation of proposed recommendations to guide future studies and reviews. Graphical abstract
Afficher plus [+] Moins [-]Modeling the temporal distribution of water, ammonium-N, and nitrate-N in the root zone of wheat using HYDRUS-2D under conservation agriculture Texte intégral
2020
Shafeeq, Poo Madhathil | Aggarwal, Pramila | Krishnan, Prameela | Rai, Vikas | Pramanik, Pragati | Das, Tapas Kumar
In the current study, the temporal distribution of both soil water and soil NO₃–N under several conservation agriculture (CA) practices during the wheat crop growth were characterized by HYDRUS-2D model. Treatments comprised of conventional tillage (CT), permanent broad beds (PBB), zero tillage (ZT), PBB with residue (PBB+R) and ZT with residue (ZT+R). Hydraulic inputs of the model, comprising the measured value of Kfₛ, α and n, obtained as the output of Rosetta Lite model were optimized through inverse modeling. Model predicted the daily change in soil water content (SWC) of the profile during the simulated period (62–91 DAS) with good accuracy (R² = 0.75; root mean squared error (RMSE) = 0.038). In general, soil water balance simulated from the model showed 50% lower cumulative drainage, 50% higher cumulative transpiration along with higher soil water retention, in PBB+R than CT. Reported values of the first-order rate constants, signify nitrification of urea to NH₄–N (μₐ) (day⁻¹) nitrification of NH₄–N to NO₃–N (μₙ) (day⁻¹) and the distribution coefficient of urea (Kd−in cm³ mg⁻¹) were optimized through inverse modeling. Later they were used as solute transport reaction input parameters of the model, to predict the daily change in NO₃–N of the profile with better accuracy (R² = 0.83; RMSE = 4.62). Since NH₄–N disappears fast, it could not be measured frequently. Therefore, not enough data could be generated for their use in the calibration and validation of the model. Results of simulation of daily NO₃–N concentration indicated a higher concentration of NO₃–N in the surface layer and its leaching losses beyond the root zone were relatively lesser in PBB+R, than CT, which resulted in less contamination of the belowground water. Thus, the study clearly recommended PBB+R to be adopted for wheat cultivation in maize–wheat cropping system, as it enhances the water and nitrogen availability in the root zone and reduce their losses beyond the root zone.
Afficher plus [+] Moins [-]Facile preparation of L-cysteine–modified cellulose microspheres as a low-cost adsorbent for selective and efficient adsorption of Au(III) from the aqueous solution Texte intégral
2020
Yang, Xin | Pan, Qi | Ao, Yinyong | Du, Jifu | Dong, Zhen | Zhai, Maolin | Zhao, Long
A facile method to synthesize adsorbent based on cellulose modified by amino acid was developed. The novel L-cysteine–functionalized adsorbent for Au(III) recovery was synthesized via radiation grafting technique. Glycidyl methacrylate (GMA) was grafted on the surface of microcrystalline cellulose microsphere (MCC); next, ring-opening reaction was performed to immobilize L-cysteine. The adsorption abilities of the adsorbent (CysR) were tested. Batch experiments suggested that the maximum adsorption capacity of Au(III) is 714.28 mg/g calculated by Langmuir model. The adsorption kinetic data was followed by pseudo-second-order model. CysR showed excellent selectivity for Au(III) even the concentration of competing ions was all ten times than that of Au(III). The column experiments revealed that Au(III) could be efficiently adsorbed by CysR competition with equal amounts of Ni(II) and Zn(II). Moreover, XPS analysis demonstrated that the adsorbed Au(III) was reduced to Au(I) and Au(0). The adsorption performance certified that CysR was a promising adsorbent for Au(III) recovery.
Afficher plus [+] Moins [-]Boosting the catalytic activity of natural magnetite for wet peroxide oxidation Texte intégral
2020
Álvarez-Torrellas, Silvia | Munoz, Macarena | Mondejar, Victor | de Pedro, Zahara M. | Casas, Jose A.
This work explores the modification of naturally occurring magnetite by controlled oxidation (200–400 °C, air atmosphere) and reduction (300–600 °C, H₂ atmosphere) treatments with the aim of boosting its activity in CWPO. The resulting materials were fully characterized by XRD, XPS, TGA, TPR, SEM, and magnetization measurements, allowing to confirm the development of core-shell type structures. The magnetite core of the solid remained unchanged upon the treatment whereas the Fe(II)/Fe(III) ratio of the shell was modified (e.g. 0.42, 0.11 and 0.63 values were calculated for pristine Fe₃O₄, Fe₃O₄-O400, and Fe₃O₄-R400, respectively). The performance of the catalysts was tested in the CWPO of sulfamethoxazole (SMX) (5 mg L⁻¹) under ambient conditions and circumneutral pH (pH₀ = 5), using the stoichiometric dose of H₂O₂ (25 mg L⁻¹) and a catalyst load of 1 g L⁻¹. The key role of the ferrous species on the mineral shell was evidenced. Whereas the oxidation of magnetite led to significantly slower degradation rates of the pollutant, its reduction gave rise to a dramatic increase, achieving the complete removal of SMX in 1.5 h reaction time with the optimum catalyst (Fe₃O₄-R400) compared to the 3.5 h required with the pristine mineral. A reaction mechanism was proposed for SMX degradation, and a kinetic equation based on the Eley-Rideal model was accordingly developed. This model successfully fitted the experimental results. The stability of Fe₃O₄-R400 was evaluated upon five sequential runs. Finally, the versatility of the catalytic system was proved in real environmentally relevant water matrices.
Afficher plus [+] Moins [-]Social benefits of improving water infrastructure in South Korea: upgrading sewage treatment plants Texte intégral
2020
Ahn, Joongha | Moon, HyungBin | Shin, Jungwoo | Ryu, Jaena
A sewage treatment plant is considered an undesirable facility because of public concerns about odor, hygiene, and lowered house prices in the neighborhood. In South Korea, many aging sewage treatment plants need to be upgraded because they show inadequate performance on the removal of major pollutants. However, issues involved in such upgrades include social conflicts between the local government and residents, and economic feasibility. Examinations of social acceptability that include economic analyses are needed in order to fulfill social demand for upgrading the sewage treatment plants while simultaneously guaranteeing efficiency and minimizing social costs. This study investigates the social benefits of expanding and modernizing sewage treatment plants in South Korea using the contingent valuation method. Results show that Korean households, on average, are willing to pay 36,340 KRW (33.25 USD) per year for upgrading sewage treatment plants. About 47.73% of the project costs can be covered by the social benefits the Korean households enjoy. This study suggests that the Korean government needs to consider estimated social benefits in determining the scale and timeline of upgrade projects. The results of this study may help with stable implementation of upgrade projects for sewage treatment plants.
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