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Impact of air pollution on hospital admissions with a focus on respiratory diseases: a time-series multi-city analysis
2019
Slama, Alessandro | Śliwczyński, Andrzej | Woźnica, Jolanta | Zdrolik, Maciej | Wiśnicki, Bartłomiej | Kubajek, Jakub | Turżańska-Wieczorek, Olga | Gozdowski, Dariusz | Wierzba, Waldemar | Franek, Edward
Together with the growing availability of data from electronic records from healthcare providers and healthcare systems, an assessment of associations between different environmental parameters (e.g., pollution levels and meteorological data) and hospitalizations, morbidity, and mortality has become possible. This study aimed to assess the association of air pollution and hospitalizations using a large database comprising almost all hospitalizations in Poland. This time-series analysis has been conducted in five cities in Poland (Warsaw, Białystok, Bielsko-Biała, Kraków, Gdańsk) over a period of almost 4 years (2014–2017, 1255 days), covering more than 20 million of hospitalizations. The hospitalizations have been extracted from the National Health Fund registries as daily summaries. Correlation analysis and distributed lag nonlinear models have been used to investigate for statistically relevant associations of air pollutants on hospitalizations, trying by various methods to minimize potential bias from atmospheric parameters, days of the week, bank holidays, etc. A statistically significant increase of respiratory disease hospitalizations has been detected after peaks of particulate matter concentrations (particularly PM₂.₅, between 0.9 and 4.5% increase per 10 units of pollutant increase, and PM₁₀, between 0.9 and 3.5% per 10 units of pollutant increase), with a typical time lag between the pollutant peak and the event of 2 to 6 days. For other pollution parameters and other types of hospitalizations (e.g., cardiovascular events, eye and skin diseases, etc.), a weaker and ununiform correlations were recorded. Ambient air pollution exposure increases are associated with a short-term increase of hospitalizations due to respiratory tract diseases. The most prominent effect was recorded with the correlation of PM₂.₅ and PM₁₀. There is only weak evidence indicating that such short-term associations exist between peaks of air pollution concentrations and increased hospitalizations for other (e.g., cardiovascular) diseases. The obtained information could be used to better predict hospitalization patterns and costs for the healthcare system and perhaps trigger additional vigilance on particulate matter pollution in the cities.
显示更多 [+] 显示较少 [-]Nanostructured catalysts applied to degrade atrazine in aqueous phase by heterogeneous photo-Fenton process
2019
Benzaquén, Tamara B. | Barrera, Deicy A. | Carraro, Paola M. | Sapag, Karim | Alfano, Orlando M. | Eimer, Griselda A.
SBA-15 and KIT-6 materials have been synthesized and modified with iron salts by the wet impregnation method with different metal loadings. The different mesostructures obtained were characterized by N₂ adsorption–desorption at 77 K, X-ray diffraction, temperature-programmed reduction, and ultraviolet–visible spectroscopy. These iron-containing mesostructured materials have been successfully tested for the heterogeneous photo-Fenton degradation of aqueous solutions of dangerous herbicides, such as atrazine, using UV–visible light irradiation, at room temperature and close to neutral pH. The results showed that the Fe/SBA-15 (10%) and Fe/KIT-6 (5%) catalysts exhibited the highest activities. However, the Fe/KIT-6 (5%) catalyst with minor Fe loading than Fe/SBA-15 (10%) presented a higher degradation of atrazine (above 98% in a reaction time of 240 min). Therefore, the interconnectivity of the cage-like mesopores had an important influence on the catalytic activity, favoring probably mass-transfer effects. Thus, the high performance of these materials indicates that the heterogeneous via of photo-Fenton process can also be efficiently employed to treat wastewaters containing pollutants such as herbicides, in order to reduce them to simplest and less toxic molecules.
显示更多 [+] 显示较少 [-]Effects of Antibiotics on Microbial Communities Responsible for Perchlorate Degradation
2019
Zheng, Xiaoxuan | Jiang, Bo | Lang, Hang | Zhang, Ruirui | Li, Yiqiang | Bian, Yingnan | Guan, Xiangyu
Perchlorate, a pervasive water pollutant, poses a threat to some aquatic environments. Antibiotics, as an emerging contaminant, have increasingly been found in aquatic environments in recent years. As a special co-contaminant, antibiotics modify the composition and function of microbial communities, and the biodegradation rate of perchlorate is changed in the environment. In this study, three typical antibiotics widely found in aquatic ecosystems (lincomycin (LIN), erythromycin (ETM), and sulfadiazine (SDZ)) and two input modes (once and multiple times) were selected to reveal the effects of antibiotics on perchlorate degradation and changes in the microbial community. Additionally, antibiotic resistance gene (ARG) abundance and microbial community composition were analyzed to illustrate the response of bacteria to antibiotic types and input methods by QPCR and high-throughput sequencing. The perchlorate degradation rate was inhibited by three antibiotics (LIN > ETM > SDZ) in this study. LIN and ETM had stronger inhibitory effects on perchlorate degradation, and the abundances of their ARGs increased with increasing antibiotic concentrations. With the continuous culturing and multiple inputs of antibiotics, the percentage of ARGs decreased after crossing a threshold. Additionally, the dominant degradation bacteria were different under pressure from different antibiotics. The type of the antibiotic, the background level of ARGs, and the dissemination of ARGs between bacteria were the main factors influencing the degradation system. The results presented herein will help us understand the modifications of microbial communities that occur in persistent pollutant systems contaminated with antibiotics.
显示更多 [+] 显示较少 [-]Effects of Biogas Slurry Application on Crop Production and Soil Properties in a Rice–Wheat Rotation on Coastal Reclaimed Farmland
2019
Tang, Yifan | Wen, Guoliang | Li, Pingping | Dai, Cheng | Han, Jiangang
The field experiment of a rice–wheat rotation system was conducted on a coastal reclaimed farmland with different application rates of biogas slurry from a large-scale standardized hoggery. Crop yield, grain quality, and soil properties were examined to determine the appropriate application rate. At the slurry application rates of 480 m³ ha⁻¹ for rice and 9.00–11.25 m³ ha⁻¹ for wheat, grain yields of rice and wheat were 8.9 and 15.7% higher than those under conventional fertilization, respectively. When 840 m³ ha⁻¹ biogas slurry was applied to the rice field, the grain amino acid content was significantly higher than that of conventionally fertilized rice. In the rice–wheat rotation system, under biogas slurry treatments, soil pH and EC did not significantly increase; the contents of soil Pb, Cr, Cu, and Zn were within allowable limits; the contents of soil alkali-hydrolyzable nitrogen were greatly increased and significantly higher than those under conventional fertilization treatment; and the content of soil organic matter had no significant difference with that under no fertilization treatment. Therefore, the recommended application rate of biogas slurry on coastal reclaimed farmland should be 480 and 9.00–11.25 m³ ha⁻¹ for rice and wheat, respectively.
显示更多 [+] 显示较少 [-]Adsorption Removal of Cr(VI) with Activated Carbon Prepared by Co-pyrolysis of Rice Straw and Sewage Sludge with ZnCl2 Activation
2019
Fan, Liangqian | Wan, Wenxin | Wang, Xianda | Cai, Jie | Chen, Fenghui | Chen, Wei | Ji, Lin | Luo, Hongbing | Cheng, Lin
In the study, an activated carbon was prepared by co-pyrolyzing rice straw and sewage sludge with ZnCl₂ activation (SS-RS AC) and used to remove Cr(VI) from wastewater. Firstly, for the preparation of SS-RS AC, the yield and iodine number were used to determine the appropriate addition percentage of rice straw. Then, a series of batch experiments including initial pH, adsorption kinetics and isotherms, and ionic strength as well as Fourier transform infrared (FT-IR) analysis of SS-RS AC before and after adsorption were performed to explore the Cr(VI) adsorption removal behavior and mechanism of SS-RS AC prepared from sewage sludge with the appropriate rice straw addition percentage. The results showed that the appropriate addition percentage of rice straw was 20%. For the Cr(VI) adsorption removal with SS-RS AC, the initial pH of solution significantly influenced the removal efficient. The highest efficiency of Cr(VI) adsorption removal (97.7%) could be attained at pH 2.0. The adsorption kinetics and isotherm data were best fitted by the pseudo-second-order model and the Langmuir-Freundlich model, respectively. The prepared SS-RS AC had the maximum Cr(VI) adsorption removal capacity of 138.69 mg/g at 40 °C. The main mechanisms for the Cr(VI) removal with SS-RS AC involve the electrostatic attraction and the reduction of Cr(VI). Carboxy, amine, and hydroxyl groups were found to act as electron donor groups, contributing to the reduction of Cr(VI). The ionic strength had an adverse effect on the Cr(VI) removal. Overall, the prepared SS-RS AC can be used as an alternative and low-cost adsorbent for the removal of Cr(VI).
显示更多 [+] 显示较少 [-]The nexus between financial development, income level, and environment in Central and Eastern European Countries: a perspective on Belt and Road Initiative
2019
Saud, Shah | Chen, Songsheng | Haseeb, Abdul | Khan, Khalid | Imran, Muhammad
A plethora of empirical work explored finance-income-environment nexus, aims to investigate high CO₂ emissions determinants, over the last few couples of decades. The prior empirical work assist the idea that finance and income have diverse impacts on the environment. The lack of consensus on finance-income-environment nexus in the Central and Eastern European Countries in the perspective of Belt and Road Initiative need to be examined. Therefore, the present study explores the nexus between financial development, income level, and environmental quality for a panel of eighteen Central and Eastern European Countries, over the period of 1980–2016. The Dynamic Seemingly Unrelated Regression, the Fully Modified Ordinary Least Squares, and the Dumitrescu-Hurlin panel casualty approaches are employed. The environmental Kuznets curve hypothesis also investigated for both time series panel and country-wise. The Dynamic Seemingly Unrelated Regression long-run panel results reveal that (i) financial development index and income negatively impact on environmental quality; (ii) energy consumption is the key determinant of CO₂ emissions and reduces environmental quality; (iii) urbanization and trade both enhance environmental quality via reduction of carbon emissions; and (iv) the environmental Kuznets curve hypothesis supported for the selected panel countries. The country-wise results depict that increase in environmental quality occurs due to increase in financial development (in four countries), income level (in five countries), trade (in five countries), and urbanization (in eight countries). However, the environmental quality decreases due to the increase in financial development (in six countries), income level (in eight countries), energy consumption (in twelve countries), trade (in six countries), and urbanization (in five countries). The environmental Kuznets curve hypothesis supported for five Central and Eastern European Countries. Additionally, the causality results confirmed the presence of feedback relationships among income and environmental quality, and financial development and energy consumption. Thus, we conclude that income level and financial development are the main drivers behind high carbon dioxide emissions in CEECs. The finding of the study opens up new insight for appropriate policymaking.
显示更多 [+] 显示较少 [-]Arsenic migration during co-processing of secondary residues from ammonium paratungstate production in cement kiln
2019
Xiao, Haiping | Ge, Jinlin | Chen, Yu | Peng, Zheng | Yan, Dahai | Li, Li | Karstensen, Kare Helge | Engelsen, Christian J. | Huang, Qifei
To reduce the environmental pollution caused by ammonium paratungstate (APT) production in the Ganzhou area in China, simulated experiments in laboratory and field experiments in cement kilns were performed. The migration characteristics of As in secondary residues (thermometallurgy and hydrometallurgy residues) from APT production in cement kilns were similar, and As in the residues existed in the form of sulfides. When the residues were fed at the kiln inlet, the As in the residues was completely distributed in the clinker after a new mass balance of As was reestablished in a very short time. When the residues were fed at the raw mill, the total input rate of As was far higher than the total output rate. Therefore, a part of As was circulated in the cement kiln, and only a small part of As was distributed in the clinker. In addition, the As concentration in the flue gas and the leaching concentration of As in the clinker were far below the limit value in the Chinese standard. For feeding rates below that are used in the field experiment, co-processing of secondary residues in a cement kiln fed at the kiln inlet is environmentally safe. However, if the secondary residues are consistently fed at the raw mill, the As concentration in the flue gas may gradually increase.
显示更多 [+] 显示较少 [-]Natural and non-toxic products from Fabaceae Brazilian plants as a replacement for traditional antifouling biocides: an inhibition potential against initial biofouling
2019
Agostini, Vanessa Ochi | Macedo, Alexandre José | Muxagata, Erik | da Silva, Márcia Vanusa | Pinho, Grasiela Lopes Leães
In this study, we screened for the antifouling activity of 15 species plant extracts from Brazilian the Brazilian Caatinga Fabaceae against the initial colonization of natural marine bacterial biofilm. We also investigated the potential toxicity of extracts against planktonic and benthic non-target organisms. Aqueous extracts of plants collected in the Caatinga biome (PE, Brazil) were prepared and tested at different concentration levels (0, 0.5, 1, 2, 4, and 8 mg mL⁻¹). Natural marine bacterial consortium was inoculated in multi-well plates and incubated with the different treatments for 48 h. The biofilm and planktonic bacterial density and biomass inhibition were evaluated along with biofilm biomass eradication. The extracts that showed the highest bacterial biofilm inhibition were evaluated for toxicity against microalgae and crustaceans. The biofilm and planktonic bacterial inhibition potential were evaluated through flow cytometry and spectrophotometry. The selected treatments were evaluated for their toxicity using the microalgae Chaetoceros calcitrans, the copepod Nitokra sp., and the brine shrimp Artemia salina as bioindicators. Our work demonstrates the biotechnological potential of Fabaceae plant compounds as a safe antifouling alternative. Anadenanthera colubrina var. cebil fruits and Apuleia leiocarpa leaf extracts showed antibiofilm activity (≥ 80%), while Myroxylon peruiferum and Dioclea grandiflora leaf extracts showed antibiotic activity. These extracts were safe to planktonic and benthic non-target organisms. The results of this study point to potential substitutes to highly toxic antifouling paints and shed light on the prospect of a yet to be explored biome for more sustainable alternatives in biofouling research.
显示更多 [+] 显示较少 [-]Alleviative role of exogenously applied mannitol in maize cultivars differing in chromium stress tolerance
2019
Habiba, Ume | Ali, Shafaqat | Rizwan, Muhammad | Ibrahim, Muhammad | Hussain, Afzal | Shahid, Muhammad Rizwan | Alamri, Saud A. | Alyemeni, Mohammed Nasser | Ahmad, Parvaiz
A pot experiment was performed to examine the role of foliar applied mannitol (M) in chromium (Cr) stress alleviation in different maize cultivars. Two maize cultivars, one tolerant (6103) and one sensitive (9108) to chromium stress, were grown in soil treated with three concentrations of Cr (0, 5, and 10 mg kg⁻¹) and three levels of mannitol (0, 50, and 100 mg L⁻¹). Chromium stress decreased the overall growth of plants by reducing the plant height, root/shoot dry weight, chlorophyll contents, and enzymatic activities, while exacerbated the severity of reactive oxygen species in both maize cultivars. Chromium-induced reduction in growth attributes of maize plants was relatively higher in sensitive cultivar than that of tolerant one. Uptake of Cr by the plants and its translocation from roots to shoots increased with increasing concentration in the soil. However, foliar application of mannitol significantly alleviated the Cr stress and improved growth, biomass, and photosynthetic pigments of maize plants. Mannitol also considerably reduced Cr contents in leaves and roots of both cultivars. Hence, it is concluded that mannitol can be helpful for crops grown on heavy metal, especially Cr, contaminated soils for remediation purpose.
显示更多 [+] 显示较少 [-]Source identification of combustion-related air pollution during an episode and afterwards in winter-time in Istanbul
2019
Kuzu, S Levent
Conventional air pollutants (PM₁₀, CO, NOₓ) gradually increased from fall to winter during 2015 in Istanbul. Several air pollution episodes were observed during this period. This study was made in order to determine polycyclic aromatic hydrocarbon (PAH) levels, identify the sources of air pollution, and make toxicity assessment based on Benzo(a)pyrene equivalent concentrations. The sampling took 14 sequential days during winter. High-pressure weather conditions prevailed at the start of the sampling. The conditions were then changed to low-pressure condition towards the end of the sampling. Strong inversion was effective on the onset of the sampling. Strong inversion was effective at the onset of the sampling. A high-volume sampler was used to collect gas and particle phase samples. Total suspended particle concentrations were between 27 and 252 μg m⁻³. Sixteen PAH species were investigated. Total (gas + particle) PAH concentrations were between 76.4 and 1280.3 ng m⁻³, with an average of 301.4 ng m⁻³. Individual PAH concentrations were between not detected (n.d.) and 99.2 ng m⁻³ in the gaseous phase, and between n.d. and 11.5 ng m⁻³ in the particle phase. Phenanthrene had the highest share among 16 PAH compounds. Benzo(a)pyrene was not detected in 8 days. On the remaining days, its concentration ranged between 5.5 and 14.8 ng m⁻³ with an average of 3.7 ng m⁻³. Low-molecular-weight PAHs dominated gaseous phase; inversely, high-molecular-weight PAHs dominated particle phase. Possible sources were identified by diagnostic ratios. These ratios suggested that coal combustion and diesel vehicle exhaust emissions had a substantial impact on ambient air quality. Benzo(a)pyrene equivalencies were calculated for each PAH compound in order to make toxicity assessment. Total benzo(a)pyrene equivalencies ranged between 0.4 and 30.0 ng m⁻³ with an average of 7.2 ng m⁻³.
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