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Thermal baths as sources of pharmaceutical and illicit drug contamination Texte intégral
2020
Jakab, Gergely | Szalai, Zoltán | Michalkó, Gábor | Ringer, Marianna | Filep, Tibor | Szabó, Lili | Maász, Gábor | Pirger, Zsolt | Ferincz, Árpád | Staszny, Ádám | Dobosy, Péter | Kondor, Attila Csaba
Despite the fact that there are tens of thousands of thermal baths in existence, knowledge about the occurrence of pharmaceutically active compounds (PhACs) in untreated thermal wastewater is very limited. Because used thermal water is typically legally discharged into surface waters without any treatment, the effluent poses environmental risks for the receiving water bodies. The aim of this study was to show the occurrence patterns and spatiotemporal characteristics of 111 PhACs in thermal wastewater. Six thermal water outflows of different thermal baths were tested in different seasons in the Budapest metropolitan region (Hungary), and diurnal analysis was performed. After solid-phase extraction, the samples were analysed and quantified by coupling supercritical fluid chromatography and mass spectrometry to perform simultaneous multi-residue drug analysis. The results confirm that water discharge pipes directly transport pharmaceuticals into surface water bodies; 34 PhACs were measured to be over the limit of quantification at least once, and 21 of them were found in more than one water sample. The local anaesthetic drug lidocaine, antiepileptic carbamazepine, analgesic derivative tramadol and illicit drug cocaine were detected in more than half of the samples. Caffeine, metoprolol and bisoprolol (cardiovascular drugs), benzoylecgonine (cocaine metabolite), diclofenac (NSAID), citalopram (antidepressant) and certain types of hormones also have a significant frequency of 30-50%. However, the occurrence and concentrations of PhACs vary according to the season and number/types of visitors. As demonstrated by the diurnal fluctuation, drug contamination of thermal waters can significantly vary, even for similar types of baths; furthermore, the quantity and types of some pollutants rapidly change in the discharged thermal wastewater.
Afficher plus [+] Moins [-]Effects and interactions of cadmium and zinc on root morphology and metal translocation in two populations of Hylotelephium spectabile (Boreau) H. Ohba, a potential Cd-accumulating species Texte intégral
2020
Guo, Junmei | Guo, Yue | Yang, Jun | Yang, Junxing | Zheng, Guodi | Chen, Tongbin | Li, Zhitao | Wang, Xuedong | Bian, Jianlin | Meng, Xiaofei
The interactions between Cd and Zn in their effects on plants are inconsistent and difficult to predict. A hydroponic experiment was conducted to investigate the effects of Cd and Zn and their interactions on root morphology and metal translocation in two populations of Hylotelephium spectabile (Boreau) H. Ohba (Crassulaceae, HB1 and HB2). Both populations showed relative tolerance to high levels of Cd and Zn, except that the leaf biomass of HB1 significantly decreased by 44.6% with 5-mg/L Cd plus 10-mg/L Zn. Root growth was inhibited in both populations by addition of 20-mg/L Zn under Cd stress, while 10-mg/L Zn showed little impact on the root growth inhibition of HB2. Roots with diameter 0.1–0.4 mm contributed most of the total root length (RL) and root surface area (RSA) of H. spectabile. In both populations, these root parameters showed greater suppression with the combined stress of Cd plus Zn than under Cd or Zn single stress, except by adding 10-mg/L Zn under Cd stress. Moreover, HB2 maintained relatively higher RL and RSA than HB1 under the different treatments, which implied that HB2 might possess a more effective mechanism than HB1 for coping in response to Cd and Zn stress. The addition of Zn not only affected the absorption of Cd but also significantly affected the distribution of Cd in different tissues of H. spectabile. A low level of Zn led to increased Cd in the stem of HB2, but an increase in Cd in the leaf and root of HB1. Addition of 10-mg/L Zn led to a significant increase by 188% and 170% in Cd accumulation in aboveground part of HB2 under 2- and 5-mg/L Cd stress, whereas the addition of Zn had little effect on Cd accumulation in HB1. Thus, strong positive interactions of Cd and Zn occurred in HB2, which showed great potential for application in phytoremediation of soil contaminated with both Cd and Zn, warranting further investigation under field condition.
Afficher plus [+] Moins [-]Impact of board characteristics on environmental disclosures for listed mining companies in China Texte intégral
2020
Agyemang, Andrew Osei | Yusheng, Kong | Ayamba, Emmanuel Caesar | Twum, Angelina Kissiwaa | Chengpeng, Zhu | Shaibu, Ali
This paper examines the impact of board characteristics on environmental accounting information disclosure for listed mining companies in China. Board characteristics were categorized into board size, independence characteristics, diversity characteristics, behavioral characteristics, and incentive characteristics. The study further extended to analyze the impact of board characteristics on environmental disclosure before and after the promulgation of Environmental Information Disclosure Degree (EIDD). Using multiple regression analysis with a sample of 34 listed mining companies from both Shanghai and Shenzhen Stock Exchanges covering 2000–2018 period, we find a significant positive correlation between board size and Environmental Accounting Disclosure Index (EADI). Also, board independence measured by independent directors and the separation of the chief executive officer from board chairman revealed a positive and significant relationship with EADI. Similarly, behavioral characteristics measured by board meeting were positively correlated with EADI at 1% significant level. In terms of diversity characteristics, both females on board and foreign nationals revealed a negative and insignificant relationship with EADI, while incentive characteristics saw an inconclusive correlation with EADI. Our findings are useful to top managers and regulators who are interested in improving corporate governance practices and environmental information disclosure.
Afficher plus [+] Moins [-]Investigating the EKC hypothesis for China: the role of economic complexity on ecological footprint Texte intégral
2020
Yilanci, Veli | Pata, Uğur Korkut
This empirical study aims to test the validity of the environmental Kuznets curve (EKC) hypothesis for China within the framework of (Narayan and Narayan Energy Policy 38(1):661–666, 2010) approach. To this end, the study employs a recently developed Fourier ARDL procedure and time-varying causality test over the period 1965–2016 to analyze the short- and long-term relationships between economic growth, economic complexity index, energy consumption, and ecological footprint. The findings of the Fourier ARDL procedure confirm the existence of cointegration among the series. Moreover, the results of this study demonstrate that energy consumption and ecological complexity increase ecological footprint in both the short- and long term. However, the short-term elasticity of economic growth is smaller than the long-term elasticity, implying that the EKC hypothesis is not valid for China. This finding is robust as it is confirmed by the time-varying causality test. The overall results illustrate that economic complexity has an increasing impact on ecological footprint, and economic growth is not effective to solve environmental problems in China. Therefore, the Chinese government should encourage a more environmentally friendly production process and cleaner technologies in exports to reduce environmental pollution.
Afficher plus [+] Moins [-]A blessing for the Yangtze River: optimization of Chinese regional policy planning for water yield and purification in the Three Gorges Reservoir Area Texte intégral
2020
Xiong, Qinli | Xiao, Yang | Halmy, Marwa Waseem A. | Pan, Kaiwen | Dakhil, Mohammed A. | Zhang, Lin | Li, Ting | Liang, Pinghan
Land use/land cover (LULC) changes impact the structure and functioning of ecosystems, which consequently influences the provisioning of a range of ecosystem services (ES). There is a growing consensus regarding the merit of integrating the evaluation of ES into regional policy planning. The Yangtze River is the world’s third longest and supports more than 6% of its population. However, assessing the potential impacts of different resource management policies upon ES is complicated in the Yangtze basin. To remedy this, here we designed a scenario analysis-based approach that used remotely sensed data and GIS (geographic information system) to analyze the relationships between ES (i.e., water flow regulation, water purification) and policies envisioned to improve human welfare in the Chongqing municipality, in the upper reaches of the Three Gorges Reservoir Area (TGRA) in the Yangtze basin. This watershed area has high population density and suffers from severe flood hazard and critical pollution issues. The GEOMOD modeling technique was used to predict LULC changes according to policy planning alternatives, producing scenarios by 2050 for the TGRA watershed. The GIS-based ES model (InVEST model) was developed as a tool to inform the decision-making process with the intention of aligning conservation measures with economic development. We examine policy effectiveness by comparing three scenarios for 2050: scenario-1 maintains the current policy, with no considerations of ES; scenario-2 integrates ES into policy planning; and scenario-3 integrates ES into policy planning considering the needs of local people. Our scenario-based LULC change analysis showed that the land with large increases in water flow regulation (i.e., values ≤–3000 × 10³ m³ km⁻²) were scattered over the entire study area, while phosphorus reduction (i.e., values ≤ –30 kg km⁻²) were located mainly along rivers in all scenarios. Scenario-2 and scenario-3 are based on policies aiming at enhancing ES provisioning; for these, the projected ecological risks of water pollution are significantly reduced (39.97% and 37.58%, respectively). Total net changes of the investigated ES under scenario-2 or scenario-3 were almost double that occurring under scenario-1. Although scenario-2 and scenario-3 showed a near-equal total net change, water purification under scenario-2 was the greatest relative to forest expansion. However, scenario-3 offered the best future environmental development scenario, as it accounted for the demand and supply characteristics of water yield and purification in different regions. The water purification service made the greatest contribution to positive and negative effects (26%–47% and -7%, respectively) on ES provisioning. Linking water purification service to policy planning would effectively improve the overall ES. These scenario forecasting results will help the Three Gorges Dam to gain more ecological benefits via improvements to water flow regulation and the effective alleviation of degraded water quality in heavily populated regions in the Yangtze basin.
Afficher plus [+] Moins [-]Degradation of bisphenol A by the UV/H2O2 process: a kinetic study Texte intégral
2020
de Araujo, Leandro Goulart | Oscar Conte, Leandro | Violeta Schenone, Agustina | Alfano, Orlando Mario | Teixeira, Antonio Carlos Silva Costa
A theoretical and experimental study of bisphenol A (BPA) degradation by the UV/H₂O₂ process in water is presented. The effects of the H₂O₂ concentration and the specific rate of photon emission (EP,₀) on BPA degradation were investigated. A kinetic model derived from a reaction sequence was employed to predict BPA and hydrogen peroxide concentrations over time using an annular photochemical reactor in batch recirculation mode. The local volumetric rate of photon absorption (LVRPA) inside the photoreactor was computed using a Line Source with Parallel Plane emission model (LSPP). From the proposed kinetic model and the experimental data, the second order rate constants of the reactions between hydroxyl radicals and the main reacting species (H₂O₂ and BPA) were estimated applying a nonlinear regression method. A good agreement between the kinetic model and experimental data, for a wide range of operating conditions, was obtained. For BPA, H₂O₂, and TOC concentrations, the calculated root means square errors (RMSE) were 2.3 × 10⁻ ², 9.8 × 10⁻ ¹, and 9.0 × 10⁻ ² mmol L⁻ ¹, respectively. The simplified kinetic model presented in this work can be directly applied to scaling-up and reactor design, since the estimated kinetic constants are independent of the reactor size, shape, and configuration. Further experiments were made by employing low BPA initial concentration (100 μg L⁻ ¹) in water and real wastewater. A lower degradation rate of BPA was observed in the real wastewater, although the UV/H₂O₂ process has also been able to completely degrade the target pollutant in less than 1 h.
Afficher plus [+] Moins [-]Modeling the nexus between pollutant emission, energy consumption, foreign direct investment, and economic growth: new insights from China Texte intégral
2020
Udemba, Edmund Ntom | Magazzino, Cosimo | Bekun, Festus Victor
Most nations are predominately preoccupied with the need to increase economic growth amidst pressure for increased energy consumption. However, higher energy consumption from fossil fuel has its environmental implication(s) especially in a high industrial economy like China. In this context, the current study explores the interaction between pollutant emission, foreign direct investment, energy consumption, tourism arrival, and economic growth for quarterly frequency data from 1995Q1 to 2016Q4 for econometrics analysis. Pesaran’s autoregressive distributed lag–bound test traces long-run relationship between all outlined variables over the investigated period. Empirical results show positive relationship between pollutant emissions with all other variables with the exception of economic growth. This further exposes the environmental degradation in China with the curtailing strength from the GDP. The Granger causality analysis detects that CO₂ emissions and energy consumption show a two-way causality observed. Also, one-way causality existing between growth and foreign direct investment is seen running to pollutant emission. Furthermore, one-way causality is observed among foreign direct investment, energy consumption, pollutant emission, and tourism arrivals with economic growth, and this established their impact on the economic growth which will be a guide to the policy implication on how to ameliorate environmental degradation from the effect of consumption of fossil energy sources and foreign direct investment–induced pollutant emission.
Afficher plus [+] Moins [-]Physiological responses of lettuce (Lactuca sativa L.) to microplastic pollution Texte intégral
2020
Li, Zhenxia | Li, Qingfei | Li, Ruijing | Zhao, Yafei | Geng, Jiahui | Wang, Guangyin
Concerns about the pollution of farmlands by microplastics and the associated toxicology have increased in recent times; however, studies on this topic are scarce. In this study, two kinds of PVC microplastics with different particle sizes (PVC-a with particle sizes from 100 nm to 18 μm, and PVC-b with particle sizes from 18 to 150 μm) and different content levels (0.5%, 1%, and 2%) were used to analyze the effects of PVC microplastics on the physiological characteristics of the lettuce root system and leaves. The results showed that PVC-a and PVC-b had no significant effect on the lettuce root activity. However, 0.5%a and 1%a significantly increased the total length, surface area, volume, and diameter of roots. In terms of leaves, PVC-a and PVC-b had no significant effect on the malondialdehyde content, but 1%a significantly increased the superoxide dismutase activity. Carotenoid synthesis was promoted by PVC-a but inhibited by PVC-b. Furthermore, 1%a could reduce the ability of light energy absorption, dissipation, capture, and electron transfer. The gray correlation analysis indicated that PVC-a correlated to a considerable degree with the indices related to photosynthesis, while PVC-b was significantly correlated with the indices related to root morphology. This study provides insights into the ecotoxicological effect of microplastics on farmland crops and associated ecological risk assessment.
Afficher plus [+] Moins [-]Urbanization increases carbon concentration and pCO2 in subtropical streams Texte intégral
2020
das Neves Lopes, Michelle | Decarli, Cleiton Juarez | Pinheiro-Silva, Lorena | Lima, Thiago Cesar | Leite, Nei Kavaguichi | Petrucio, Mauricio Mello
Urbanization growth may alter the hydrologic conditions and processes driving carbon concentrations in aquatic systems through local changes in land use. Here, we explore dissolved carbon concentrations (DIC and DOC) along urbanization gradient in Santa Catarina Island to evaluate potential increase of CO₂ in streams. Additionally, we assessed chemical, physical, and biotic variables to evaluate direct and indirect effects of urbanization in watersheds. We defined 3 specific urbanization levels: high (> 15% urbanized area), medium (15–5% urbanized area), and low (< 5% urbanized area) urbanization. The results showed that local changes due to growth of urban areas into watersheds altered the carbon concentrations in streams. DOC and DIC showed high concentrations in higher urbanization levels. The watersheds with an urban building area above 5% showed pCO₂ predominantly above the equilibrium with the atmosphere. These findings reveal that local modifications in land use may contribute to changes in global climate by altering the regional carbon balance in streams.
Afficher plus [+] Moins [-]Is technological innovation the effective way to achieve the “double dividend” of environmental protection and industrial upgrading? Texte intégral
2020
Wang, Gege | Liu, Shulin
In recent years, the global emphasis on environmental protection issues has gradually increased. The existing literature has been divided on whether environmental regulation promotes or inhibits industrial development. Can the innovation-driven strategy proposed by China achieve a win-win situation for both? This paper attempts to investigate the technology innovation of China’s three major economic zones in dual environmental regulation effect on industrial structure upgrade. The research was conducted based on Intermediary Effect Model and employing the technique of Image Analysis, panel data of 30 Chinese provincial from in 2005 to 2017 were selected and analyzed. The results demonstrate that the direct effect of formal environmental regulations (ER) on industrial upgrading is an inverted “U” shape, and it is positively affecting industrial upgrading through technological innovation strategies. However, the mediating role of technological innovation under the informal environmental regulation (IER) is negative. The effect of the innovation-driven strategy has regional heterogeneity, and marketization is conducive to industrial upgrading, but increasing dependence on foreign trade is not conducive to industrial upgrading. The research above politically suggests that China should further strengthen formal and informal environmental regulations, the informal environmental regulation system should be improved, and feedback mechanisms such as laws should be established. Meanwhile, the government should carry out innovation-driven strategies based on local conditions, improve the innovation mechanism, and enhance the diffusion of technological innovation.
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