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Effects of commonly used therapeutic drugs, paracetamol, and acetylsalicylic acid, on key physiological traits of the sea snail Gibbula umbilicalis Полный текст
2019
Giménez, Valéria | Nunes, Bruno
Effects of commonly used therapeutic drugs, paracetamol, and acetylsalicylic acid, on key physiological traits of the sea snail Gibbula umbilicalis Полный текст
2019
Giménez, Valéria | Nunes, Bruno
Over time, the consumption of pharmaceutical drugs has highly augmented, directly contributing for an increase of the discharges of these substances into sewage water due to excretion, and their direct release to the environment, with or without adequate treatment. Considering that part of the sewage water is dumped into rivers and seas, this is the major source of contamination of the aquatic environment. Paracetamol and acetylsalicylic acid are among the most worldwide consumed pharmaceutical drugs, frequently found in wastewater discharges and consequently in the aquatic environment in considerable amounts, posing ecotoxicity concerns especially towards aquatic non-target species. Thus, it is important to study the ecotoxicological implications that these drugs might pose to organisms from aquatic environments. The objective of this study was to assess the toxic effects of these two compounds on key biochemical features (antioxidant defenses and damage, metabolism, and cholinergic neurotoxicity) of the marine snail species Gibbula umbilicalis after an acute (96 h) exposure, simulating pulses of contamination. In order to understand the effects that those drugs have on this species, the biochemical biomarkers analyzed were the activities of catalase (CAT), glutathione-S-transferases (GSTs), cholinesterases (ChEs), and the levels of lipid peroxidation (TBARS). After acute exposure to paracetamol, catalase activity decreased significantly in organisms exposed to both highest concentrations; no significant alterations were observed for glutathione-S-transferases activity; TBARS concentration decreased significantly in organisms exposed to the intermediate and both highest concentrations, and cholinesterase activity increased significantly in animals exposed to the lowest concentration. However, after acute exposure to acetylsalicylic acid, catalase activity increased significantly; no significant alterations were observed for glutathione-S-transferases activity, and TBARS concentrations and cholinesterase activity increased. This set of data shows that G. umbilicalis is highly responsive to the presence of the tested drugs, and may thus be a promising species to serve as test organism in future marine ecotoxicological testing. The adoption of this species may broaden the offer of highly ecologically representative test organisms to be included in biomonitoring projects of the coastal and marine environment. Furthermore, it is possible to suggest that both drugs may pose significant deleterious effects of pro-oxidative origin to the physiology of the selected species, with potential adverse ecological consequences, even after short periods of exposure. The absence of neurotoxicity showed that despite being able to trigger antioxidant mechanisms, both drugs did not affect neurotransmission.
Показать больше [+] Меньше [-]Effects of commonly used therapeutic drugs, paracetamol, and acetylsalicylic acid, on key physiological traits of the sea snail Gibbula umbilicalis Полный текст
2019
Giménez, Valéria | Nunes, Bruno
Over time, the consumption of pharmaceutical drugs has highly augmented, directly contributing for an increase of the discharges of these substances into sewage water due to excretion, and their direct release to the environment, with or without adequate treatment. Considering that part of the sewage water is dumped into rivers and seas, this is the major source of contamination of the aquatic environment. Paracetamol and acetylsalicylic acid are among the most worldwide consumed pharmaceutical drugs, frequently found in wastewater discharges and consequently in the aquatic environment in considerable amounts, posing ecotoxicity concerns especially towards aquatic non-target species. Thus, it is important to study the ecotoxicological implications that these drugs might pose to organisms from aquatic environments. The objective of this study was to assess the toxic effects of these two compounds on key biochemical features (antioxidant defenses and damage, metabolism, and cholinergic neurotoxicity) of the marine snail species Gibbula umbilicalis after an acute (96 h) exposure, simulating pulses of contamination. In order to understand the effects that those drugs have on this species, the biochemical biomarkers analyzed were the activities of catalase (CAT), glutathione-S-transferases (GSTs), cholinesterases (ChEs), and the levels of lipid peroxidation (TBARS). After acute exposure to paracetamol, catalase activity decreased significantly in organisms exposed to both highest concentrations; no significant alterations were observed for glutathione-S-transferases activity; TBARS concentration decreased significantly in organisms exposed to the intermediate and both highest concentrations, and cholinesterase activity increased significantly in animals exposed to the lowest concentration. However, after acute exposure to acetylsalicylic acid, catalase activity increased significantly; no significant alterations were observed for glutathione-S-transferases activity, and TBARS concentrations and cholinesterase activity increased. This set of data shows that G. umbilicalis is highly responsive to the presence of the tested drugs, and may thus be a promising species to serve as test organism in future marine ecotoxicological testing. The adoption of this species may broaden the offer of highly ecologically representative test organisms to be included in biomonitoring projects of the coastal and marine environment. Furthermore, it is possible to suggest that both drugs may pose significant deleterious effects of pro-oxidative origin to the physiology of the selected species, with potential adverse ecological consequences, even after short periods of exposure. The absence of neurotoxicity showed that despite being able to trigger antioxidant mechanisms, both drugs did not affect neurotransmission. | published
Показать больше [+] Меньше [-]Assessing the “superposed” effects of storm surge from a Category 3 hurricane and continuous sea-level rise on saltwater intrusion into the surficial aquifer in coastal east-central Florida (USA) Полный текст
2019
Xiao, Han | Tang, Yin
Saltwater intrusion into the surficial aquifer in coastal east-central Florida (USA) due to the effects of storm surges from tropical cyclones and continuous sea-level rise is a detrimental issue resulting in groundwater quality deterioration and bio-diverse ecosystem degradation. In this study, groundwater flow and salinity transport models using SEAWAT are developed for quantifying the “superposed” effects of storm surge (SS) from a Category 3 hurricane (Hurricane Jeanne which hit the Florida Atlantic coast on September 24–27, 2004) and continuous sea-level rise (SLR) on saltwater intrusion (SWI) into the surficial aquifer in coastal east-central Florida from the year of 2004 to 2024, and the simulated time-variant extent of SS- and SLR-induced landward migration of saline groundwater is compared for determination of whether the effects of SS from a Category 3 hurricane or continuous SLR on SWI are more significant. Results indicate that (1) the effects of SS are more significant than the effects of SLR within the first 12, 10, or 9 years after its occurrence date if sea level rises in low, mid, or high rate; (2) the effects of SS are more significant than the effects of SLR if SS occurs at least once within its return period (8–12 years); and (3) the maximum effects of SS are “equivalent” to the effects of the 95-year SLR, 45-year SLR, or 28-year SLR if sea level rises to 0.3 m in low, mid, or high rate. The outcome of this study warns public to pay more attention to the detrimental “superposed” effects of SS and SLR on SWI into the surficial aquifer in coastal east-central Florida.
Показать больше [+] Меньше [-]Sharing the costs and benefits of climate change mitigation via Shapley value Полный текст
2019
Luqmān, Muḥammad | Soytaş, Uğur | Xu, Yipeng | Huang, Shaoan
This paper examines the free rider problem that exists in the joint effort to mitigate climate change. There is a need to develop a model that is stable and that provides evidence of an objective burden sharing rule so that the environmental agreement is more acceptable. This study approaches this problem via a cooperative game at the global level to make International Environmental Agreements (IEA) more stable. For this purpose, we apply the Shapley value transfer mechanism and find that under the commitment scenario, some regions attain the maximum benefits by joining the coalition. Shapley value transfer improves the coalition size and increases the global benefits at a certain level of abatement under perfect cooperation. Imperfect cooperation leads to lower levels of global benefits. Our findings offer new implications on how to improve the international cooperation for climate change. Commitments by major regions could activate the IEA (e.g., Paris agreement) efficiently. For the maximum global response to climate change, the national governments must reformulate and implement policies to meet their intended nationally determined contributions (INDCs). The results of this study also help the national governments to set their implementation priorities to implement the Paris Accord at global level.
Показать больше [+] Меньше [-]Removal of particulate matter and trace elements from ambient air by urban greenery in the winter season Полный текст
2019
Przybysz, Arkadiusz | Nersisyan, Gayane | Gawroński, Stanisław Waldemar
Particulate matter (PM) is one of the most harmful inhaled pollutants. When PM is emitted into the atmosphere, the only possible method for cleaning ambient air is through vegetation acting as biological filters for pollutants. However, in winter periods when the concentration of PM is usually the highest, the efficiency of plants is very low. The aim of this work was therefore to examine the accumulation of PM and selected trace elements (TE) by three species, evergreen coniferous Taxus baccata L. and Pinus nigra Arn., and deciduous Carpinus betulus L. during the winter season. The highest amounts of PM accumulated on the foliage of P. nigra, while TE on the leaves of C. betulus. Most of the PM accumulated on plant foliage belonged to the large fraction size (10–100 μm) and was deposited on the surface of foliage (SPM). The concentration of four TE (Ni, Pb, Cd, and Sb) was higher in PM accumulated on foliage, while in the case of three other TE (Zn, Cr and Mg), their concentration was higher in plant tissue. The TE were recorded in all PM size fractions and were rather equally distributed between surface PM (SPM) and in-wax PM (WPM). These findings have implications for urban plantings in countries with short vegetative season, where tolerant conifer species and deciduous species which keep foliage through winter should be included in urban forest plantings due to their efficiency in the removal of pollutants from the air.
Показать больше [+] Меньше [-]Production, characterization and effectiveness of cellulose acetate functionalized ZnO nanocomposite adsorbent for the removal of Se (VI) ions from aqueous media Полный текст
2019
Gurunathan, Padmalaya | Hari, Sivaram | Suseela, Sreeja Balakrishnapillai | Sankararajan, Radha | Mukannan, Arivanandan
In this study, ZnO functionalized cellulose acetate nanocomposite (ZnO/CA NC) was synthesized using a simple chemical approach found to have a high surface area of 657.34 m²/g and utilized as adsorbents for the removal of Se (VI) from aqueous solutions. Investigations on X-ray diffraction (XRD) revealed that ZnO nanocomposite has a smaller crystallite size compared to ZnO nanoparticles which facilitated for reduced agglomeration confirmed by scanning electron microscopy (SEM). The ensuing properties of ZnO/CA NC displayed high maximum adsorption capacity of 160.5 mg/g for Se (VI) ions. Inner-sphere surface complexes on ZnO/CA NC under prevailing conditions for Se (VI) were discussed using FTIR spectroscopical results. In order to evaluate the removal efficiency, the effects of adsorbent dosage, pH, and temperature were thoroughly investigated. The amount of Se (VI) ions adsorbed on ZnO/CA NC was also determined by zeta potential. The fractional removal of pollutants (Se (VI)) was done using mass transfer model. In addition, prominent adsorption capacity was also tested utilizing concurrent anions (SO₄²⁻, Cl⁻, and F⁻) with reference to Se (VI) and cost prudent regenerability of adsorbent by NaOH solution was ascertained with anti-interference and recovery steps. ZnO/CA NC was obtained by simple chemical methodology and high surface adsorption capacities supply an encouraging technique for Se (VI) removal in water treatment applications.
Показать больше [+] Меньше [-]Enhanced inactivation of antibiotic-resistant bacteria isolated from secondary effluents by g-C3N4 photocatalysis Полный текст
2019
Ding, Ning | Chang, Xueming | Shi, Na | Yin, Xiufeng | Qi, Fei | Sun, Yingxue
The extensive use of antibiotics has resulted in the development of antibiotic-resistant bacteria (ARB), which may not be completely removed by traditional wastewater treatment processes. More effective approaches to disinfection are needed to prevent the release of ARB into the surface water. The metal-free photocatalyst graphitic carbon nitride (g-C₃N₄) has aroused great interest as a possible agent for water and wastewater treatment, due to its low cytotoxicity and photoactivity with visible light. In this study, the efficacy of g-C₃N₄ was assessed as a possible means to enhance ARB inactivation by irradiation. ARB were isolated and purified from secondary effluents in 4 municipal wastewater treatment plants. Of these, 4 typical multi-drug ARB isolates, belonging to Enterobacteriaceae, were selected for irradiation experiments. Inactivation was seen to increase with irradiation time. At 60 min, the inactivation of the 4 ARB isolates by light at > 300 nm and > 400 nm was in the range of 0.25–0.39 log and 0.16–0.19 log, respectively. The use of g-C₃N₄-mediated photocatalysis at the same wavelengths significantly enhanced that to 0.64–1.26 log and 0.31–0.41 log, respectively. The antibiotic susceptibility of the ARB isolates remained unchanged either prior to or after irradiation and was independent of photon fluence, reaction time, and the presence of g-C₃N₄. This study establishes a baseline for understanding the effectiveness of g-C₃N₄ photocatalysis on inactivation of ARB in wastewaters and lays the foundation for further improvement in the use of photocatalysis for wastewater treatment.
Показать больше [+] Меньше [-]Protective effects of kefir against deltamethrin-induced hepatotoxicity in rats Полный текст
2019
El Golli-Bennour, Emna | Timoumi, Rim | Annaibi, Emna | Mokni, Moncef | Omezzine, Asma | Bacha, Hassen | Abid-Essefi, Salwa
Deltamethrine (DLM) is a synthetic pyrethroid with broad spectrum activities against acaricides and insects. Widely used for agricultural and veterinary purposes, its human and animal exposure occurs by ingestion of contaminated water and food and leads to serious health problems. Kefir is fermented milk with numerous health favors counting restorative properties of bacterial flora, immune system stimulation, cholesterol reduction, as well as anti-mutagenic and anti-tumor properties. The present study was undertaken to examine the hepatoprotective and antioxidant potential of kefir against DLM toxicity in male Wistar albino rats. DLM-treated animals revealed a significant increase in serum biochemical parameters as well as hepatic protein and lipid oxidations but caused an inhibition in antioxidant enzymes. Additionally, we have observed an increase in hepatocyte DNA damages. This toxic effect was confirmed by histological study. Kefir administration normalized the elevated serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), total bilirubin (T bilirubin), and cholesterol. It also reduced DLM-induced protein carbonyl (PC) and malondialdehyde (MDA) formations. Furthermore, Kefir treatment restored catalase (CAT) and superoxide dismutase (SOD) activities. The co-treatment as well as the pre-treatment by kefir showed an improvement of oxidative status as well as suppressed inflammation and DNA damages. However, the pre-treatment seems to be the most efficient. Therefore, it could be concluded that kefir is a natural product able to protect against the hepatotoxic effects of DLM by its free radical-scavenging and potent antioxidant activity.
Показать больше [+] Меньше [-]Research on efficiency evaluation model of integrated energy system based on hybrid multi-attribute decision-making Полный текст
2019
Li, Yan
The efficiency evaluation model of integrated energy system, involving many influencing factors, and the attribute values are heterogeneous and non-deterministic, usually cannot give specific numerical or accurate probability distribution characteristics, making the final evaluation result deviation. According to the characteristics of the integrated energy system, a hybrid multi-attribute decision-making model is constructed. The evaluation model considers the decision maker’s risk preference. In the evaluation of the efficiency of the integrated energy system, the evaluation value of some evaluation indexes is linguistic value, or the evaluation value of the evaluation experts is not consistent. These reasons lead to ambiguity in the decision information, usually in the form of uncertain linguistic values and numerical interval values. In this paper, the risk preference of decision maker is considered when constructing the evaluation model. Interval-valued multiple-attribute decision-making method and fuzzy linguistic multiple-attribute decision-making model are proposed. Finally, the mathematical model of efficiency evaluation of integrated energy system is constructed.
Показать больше [+] Меньше [-]Effects of energy consumption and economic growth on environmental quality: evidence from Qatar Полный текст
2019
Ṣalāḥuddīn, Muḥammadu | Gow, Jeff
This study examines the empirical effects of four variables: economic growth, energy consumption, foreign direct investment, and financial development on environmental quality in Qatar. Three environmental quality indicators, namely, per capita CO₂ emissions, energy intensity (EI), and Adjusted National Savings (ANS) are used to examine the interactions between the variables using a time series dataset for the period 1980−2016. Following an appropriate multiple structural breaks unit root and cointegration tests, short- and long-run coefficients were estimated through the application of Autoregressive Distributive Lag (ARDL) model. The Toda-Yamamoto (TY) causality test was conducted to determine the causal link, if any, among the variables. Estimated results suggest a detrimental long-run effect of energy consumption on all three indicators of environmental quality. FDI has a negative long-run effect on environmental quality when it is measured by EI only. Financial development has no significant effect on any of the indicators. Bidirectional causality are noted between three variables: economic growth, energy consumption, and financial development and all three indicators of environmental quality. Policy implications are discussed.
Показать больше [+] Меньше [-]The effect of the earthworm Lumbricus rubellus on the bioavailability of cadmium and lead to the springtail Folsomia candida in metal-polluted field soils Полный текст
2019
Ardestani, Masoud M. | Giska, Iwona | Gestel, Cornelis A. M. van
The bioavailability of metals can be influenced not only by soil properties but also by other species living at polluted sites. However, in laboratory experiments, usually only one test species is used to estimate bioavailability. In this study, a two-species approach was applied to assess the impact of the earthworm Lumbricus rubellus on the bioavailability of cadmium and lead to the springtail Folsomia candida using natural soils from a gradient of metal pollution. Earthworms were kept in half of the soil replicates for 4 weeks. Subsequently, the uptake and elimination kinetics of cadmium and lead in F. candida exposed for 21 days to the soils was determined. Earthworm activity affected soil properties but did not significantly affect metal uptake rate constants in springtails. The slightly higher uptake due to the presence of earthworms, which was consistent in all tested soils and for both metals, suggests that further research is needed on the role of species interactions in affecting metal bioavailability in soil.
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