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Ny-Ålesund-oriented organic pollutants in sewage effluent and receiving seawater in the Arctic region of Kongsfjorden Texte intégral
2020
Choi, Younghun | Kim, Kitae | Kim, Deokwon | Moon, Hyo-bang | Jeon, Junho
Ny-Ålesund, one of four permanent settlements on Spitsbergen in Svalbard, is a research town that includes scientific institutes from many countries. Because of daily-used chemicals (e.g., pharmaceutical and personal care products (PPCPs)) used by residents in the area, generated sewage is considered as a point source in the Kongsfjorden. The aim of the present study was to identify and quantify organic pollutants in the effluent and along the shoreline and offshore via target, suspect, and non-target screening using liquid chromatography–high-resolution mass spectrometry. We tentatively identified 30 compounds using the suspect and non-target screening methods in effluent samples from our first visit to the settlement in 2016. Among these, 3 were false positive, 24 were confirmed, and the 3 remaining compounds were not confirmed because of a lack of reference standards. Of the confirmed, 21 were quantifiable and considered target compounds for the 2nd year study. The quantified compounds in the effluent samples in 2017 totaled 17, including PPCPs, pesticides, perfluorinated compounds, and their metabolites. Some of the compounds, such as caffeine, paraxanthine/theophylline, acetaminophen, cetirizine, diethyl toluamide (DEET), and icaridin, were also detected in the receiving seawater. The concentration range was from 4 to 280,000 ng/L in the effluent and 2–98 ng/L in the seawater. Other 24 compounds were tentatively identified in the second-year effluent samples. Five were further confirmed using reference standards. Prioritization was performed on the 47 substances screened in Ny-Ålesund using the exposure and toxicity index. As the result, the top seven substances of concern present were perfluorooctanesulfonic acid (PFOS), triphenyl phosphate (TPHP), irbesartan, DEET, acetaminophen, caffeine, and paraxanthine/theophylline. As the effluent was identified as a source of the concerned organic pollutants, an emission reduction strategy should take place for protection of Arctic Fjorden environment.
Afficher plus [+] Moins [-]Oxygen mobility and microstructure properties-redox performance relationship of Rh/(Ce,Zr,La)O2 catalysts Texte intégral
2020
Wang, Ting | Zhou, Ren-xian
Rh/(Ce,Zr,La)O₂ (CZL) catalysts with different Ce/Zr molar ratios of 1:0, 8:1, 4:1, 2:1, 1:1, 1:2, 1:4, 1:8 and 0:1 were prepared. The relationship of microstructure, dynamic oxygen mobility and the redox properties with catalytic activity for HC, CO and NOₓ eliminations were investigated. The results demonstrate that CZL mixed oxide with Ce/Zr ratio of 1:1 exhibits the largest OSC values as 904.3 umol·g⁻¹ and structural defects. The increase of oxygen vacancies and structural defects would promote the interaction between Rh species and CZL mixed oxides, which further promotes the stabilization of RhOₓ particles and enhances the oxygen storage/release ability. Rh/CZLx catalysts with Ce/Zr molar ratio of 1:1–1:4 exhibit better catalytic activity and wider dynamic operation window due to their higher DOSC.
Afficher plus [+] Moins [-]Long-lasting effect of mercury contamination on the soil microbiota and its co-selection of antibiotic resistance Texte intégral
2020
Mahbub, Khandaker Rayhan | King, William L. | Siboni, Nachshon | Nguyen, Viet Khue | Rahman, Mohammad Mahmudur | Megharaj, Mallavarapu | Seymour, Justin R. | Franks, Ashley E. | Labbate, Maurizio
Long-lasting effect of mercury contamination on the soil microbiota and its co-selection of antibiotic resistance Texte intégral
2020
Mahbub, Khandaker Rayhan | King, William L. | Siboni, Nachshon | Nguyen, Viet Khue | Rahman, Mohammad Mahmudur | Megharaj, Mallavarapu | Seymour, Justin R. | Franks, Ashley E. | Labbate, Maurizio
Antibiotic resistance genes (ARGs) in the environment are an exposure risk to humans and animals and is emerging as a global public health concern. In this study, mercury (Hg) driven co-selection of ARGs was investigated under controlled conditions in two Australian non-agricultural soils with differing pH. Soils were spiked with increasing concentrations of inorganic Hg and left to age for 5 years. Both soils contained ARGs conferring resistance to tetracycline (tetA, tetB), sulphonamides (sul1), trimethoprim (dfrA1) and the ARG indicator class 1 integron-integrase gene, intI1, as measured by qPCR. The last resort antibiotic vancomycin resistance gene, vanB and quinolone resistance gene, qnrS were not detected. Hg driven co-selection of several ARGs namely intI1, tetA and tetB were observed in the alkaline soil within the tested Hg concentrations. No co-selection of the experimental ARGs was observed in the neutral pH soil. 16S rRNA sequencing revealed proliferation of Proteobacteria and Bacteriodetes in Hg contaminated neutral and alkaline soils respectively. Multivariate analyses revealed a strong effect of Hg, soil pH and organic carbon content on the co-selection of ARGs in the experimental soils. Additionally, although aging caused a significant reduction in Hg content, agriculturally important bacterial phyla such as Nitrospirae did not regrow in the contaminated soils. The results suggest that mercury can drive co-selection of ARGs in contaminated non-agricultural soils over five years of aging which is linked to soil microbiota shift and metal chemistry in the soil.
Afficher plus [+] Moins [-]Long-lasting effect of mercury contamination on the soil microbiota and its co-selection of antibiotic resistance Texte intégral
2020
Mahbub, K.R. | King, W.L. | Siboni, N. | Nguyen, V.K. | Rahman, M.M. | Megharaj, M. | Seymour, J.R. | Franks, A.E. | Labbate, M.
Antibiotic resistance genes (ARGs) in the environment are an exposure risk to humans and animals and is emerging as a global public health concern. In this study, mercury (Hg) driven co-selection of ARGs was investigated under controlled conditions in two Australian non-agricultural soils with differing pH. Soils were spiked with increasing concentrations of inorganic Hg and left to age for 5 years. Both soils contained ARGs conferring resistance to tetracycline (tetA, tetB), sulphonamides (sul1), trimethoprim (dfrA1) and the ARG indicator class 1 integron-integrase gene, intI1, as measured by qPCR. The last resort antibiotic vancomycin resistance gene, vanB and quinolone resistance gene, qnrS were not detected. Hg driven co-selection of several ARGs namely intI1, tetA and tetB were observed in the alkaline soil within the tested Hg concentrations. No co-selection of the experimental ARGs was observed in the neutral pH soil. 16S rRNA sequencing revealed proliferation of Proteobacteria and Bacteriodetes in Hg contaminated neutral and alkaline soils respectively. Multivariate analyses revealed a strong effect of Hg, soil pH and organic carbon content on the co-selection of ARGs in the experimental soils. Additionally, although aging caused a significant reduction in Hg content, agriculturally important bacterial phyla such as Nitrospirae did not regrow in the contaminated soils. The results suggest that mercury can drive co-selection of ARGs in contaminated non-agricultural soils over five years of aging which is linked to soil microbiota shift and metal chemistry in the soil. | Khandaker Rayhan Mahbub, William L. King, Nachshon Siboni, Viet Khue Nguyen, Mohammad Mahmudur Rahman, Mallavarapu Megharaj, Justin R. Seymour, Ashley E. Franks, Maurizio Labbate
Afficher plus [+] Moins [-]Environmental losses and driving forces of nitrogen flow in two agricultural towns of Hebei province during 1997–2017 Texte intégral
2020
Wang, Fangfang | Wang, Yanhua | Cai, Zucong | Chen, Xi
Excessive nitrogen (N) losses from food production and consumption have resulted in noticeable environmental impacts, e.g., air pollution and climate change, saturation of soil N, and water eutrophication. In the present study, a rural-scale N flow model was constructed in Quzhou county, Hebei province to investigate the characteristics of the N flux, N use efficiency (NUE), and N loss and their driving factors in the food production and consumption system during 1997–2017. Our results show that the N fluxes of the crop-production subsystem (CPS), the livestock-breeding subsystem (LBS), and the household-consumption subsystem (HCS) all followed an upward trend. During 1997–2017, the N losses from the system were high (51.38%), and the CPS was a major source. When the N fertilizer application level was optimal (403–475 kg N ha⁻¹), the NUE in the CPS (NUEc) decreased sharply, resulting in a higher N cost than that observed at larger scales. For the LBS, the NUE of animal feed (NUEa) was high (46.37%); however, the waste utilization rate of the HCS was below 30%. The chemical fertilizer application level, feed input, animal-food demand, and livestock manure application level were closely related to the environmental N losses. Due to the lack of reasonable N treatment and utilization methods, the increasing N losses are expected to have a large future impact on environmental issues such as haze, soil acidification, and frequent algal blooms. Therefore, adjusting N management in the processes of food production and consumption is of great significance to the improvement of global NUE and reduction of environmental pollution.
Afficher plus [+] Moins [-]Sources and spatio-temporal distribution of aerosol polycyclic aromatic hydrocarbons throughout the Tibetan Plateau Texte intégral
2020
Zheng, Huijun | Kang, Shichang | Chen, Pengfei | Li, Quanlian | Tripathee, Lekhendra | Maharjan, Linda | Guo, Junming | Zhang, Qianggong | Santos, Ewerton
With the recent rapid development of urbanization, atmospheric pollutants such as polycyclic aromatic hydrocarbons (PAHs) have attracted wide attention, particularly in remote regions. The Tibetan Plateau (TP), known as the third pole is adjacent to areas with heavy atmospheric pollution, such as South and East Asia. However, the spatial distribution and sources of PAHs on the TP remain unclear. Thus, we investigated the sources and spatio-temporal distributions of PAHs on the TP by combining aerosol sample data from six sites, including Ngari (NG), Laohugou (LHG), Beiluhe (BLH), Nam Co (NMC), Everest (EV), and Yulong (YL), in 2014 and 2016. The average concentrations of 15 PAHs at the six sites ranged from 3.4 to 15.2 ng m⁻³, with a decreasing trend from the marginal to inner areas of the plateau. The highest concentration was that in YL in the southeastern part of the TP, with an average of 15.2 ng m⁻³. The PAH concentrations in NG, NMC, and YL were higher in autumn and winter and lower in summer. High molecular weight PAHs usually exists in the particulate phase whereas tricyclic PAHs can change from particulate to gaseous phase, therefore it can indicate long-range transport. Tricyclic PAHs were the dominant PAHs on the TP (44%–58%), indicating long-range atmospheric transport as the major source of PAHs. Principal component analysis (PCA) and diagnostic ratio analysis showed that biomass and coal combustion were the major sources of PAHs in inland areas of the TP; however, marginal plateau areas were affected by fossil fuel emissions. Compared with levels in Beijing and other urban sites, the toxic equivalent quantity (TEQ) was low (0.36–1.06 ng m⁻³), suggesting a low risk to human and ecosystem health.
Afficher plus [+] Moins [-]Microbial community evolution during the aerobic biodegradation of petroleum hydrocarbons in marine sediment microcosms: Effect of biostimulation and seasonal variations Texte intégral
2020
Hamdan, Hamdan Z. | Salam, Darine A.
Evolution of the microbial community structure in crude oil contaminated marine sediments was assessed under aerobic biodegradation during wet (18 °C) and dry (28 °C) seasons experiments, to account for seasonal variations in nutrients and temperature, under biostimulation and natural attenuation conditions. NMDS showed significant variation in the microbial communities between the wet and the dry season experiments, and between the biostimulation and the natural attenuation treatments in the dry season microcosms. No significant variation in the microbial community and oil biodegradation was observed during the wet season experiments due to high background nitrogen levels eliminating the effect of biostimulation. Larger variations were observed in the dry season experiments and were correlated to enhanced alkanes removal in the biostimulated microcosms, where Alphaproteobacteria dominated the total microbial community by the end of biodegradation (54%). Many hydrocarbonoclastic bacterial genera showed successive dominance during the operation affecting the ultimate performance of the microcosms.
Afficher plus [+] Moins [-]Composition characterization and biotransformation of dissolved, particulate and algae organic phosphorus in eutrophic lakes Texte intégral
2020
Feng, Weiying | Yang, Fang | Zhang, Chen | Liu, Jing | Song, Fanhao | Chen, Haiyan | Zhu, Yuanrong | Liu, Shasha | Giesy, John P.
Characteristics and transformation of organic phosphorus in water are vital to biogeochemical cycling of phosphorus and support of blooms of phytoplankton and cyanobacteria. Using solution ³¹P nuclear magnetic resonance (NMR), combined with field surveys and lab analyses, composition and structural characteristics of dissolved phosphorus (DP), particulate phosphorus (PP) and organic P in algae were studied in two eutrophic lakes in China, Tai Lake and Chao Lake. Factors influencing migration and transformation of these constituents in lake ecosystems were also investigated. A method was developed to extract, flocculate and concentrate DP and PP from lake water samples. Results showed that orthophosphate (Ortho-P) constituted 32.4%–81.3% of DP and 43.7%–54.9% of PP, respectively; while monoester phosphorus (Mono-P) was 13.2%–54.0% of DP and 32.9%–43.7% of PP, respectively. Phosphorus in algae was mostly organic P, especially Mono-P, which was ≥50% of TP. Environmental factors and water quality parameters such as temperature (T), electrical conductivity (EC), pH, secchi depth (SD), dissolved oxygen (DO), chemical oxygen demand (CODcᵣ), chlorophyll-a (Chl-a), affected the absolute and relative concentrations of various P components in the two lakes. Increased temperature promoted bioavailable P (Ortho-P and Mono-P) release to the lake waters. The results can provide an important theoretical basis for the mutual conversion process of organic P components between various media in the lake water environment.
Afficher plus [+] Moins [-]Biological effects from environmental pollution by toxic metals in the “land of fires” (Italy) assessed using the biomonitor species Lunularia cruciata L. (Dum) Texte intégral
2020
Maresca, Viviana | Sorbo, Sergio | Loppi, Stefano | Funaro, Federica | Del Prete, Davide | Basile, Adriana
The liverwort Lunularia cruciata was collected from the town of Acerra, in the heart of the so-called ‘Land of Fires’ a large area in the eastern part of Campania region of Italy affected by burning of waste and fraudulent dumping and one of the vertices of the “Italian Triangle of Death” so said for the high incidence and mortality from tumors. The data obtained from these samples were compared with samples collected in two other sites representing two different environmental conditions. The soil below the samples, and gametophytes, were collected and analyzed for the concentration of Al, As, Ba, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, V. DNA damage, Reactive Oxygen Species production and localization, activity of antioxidant enzymes and presence of chelating molecules were investigated. All biomarkers provided an answer closely related to the pollution conditions at the 3 sites. We discuss the data considering the possibility of using these biological changes as environmental pollution biomarkers. Finally, it is underlined the importance of phytochelatins due to of their specificity for metal pollution.
Afficher plus [+] Moins [-]China is implementing “Garbage Classification” action Texte intégral
2020
Tong, Yeqing | Liu, Jiafa | Liu, Sizhe
In recent days, garbage classification has become a hot topic in China, and Shanghai took the lead in the implementation of garbage classification legislation in China. Starting from the current situation of garbage classification in China, this study emphasizes the garbage classification in terms of law, amount, economy, management, resourcing and successful experience of garbage classification in China, so as to provide inspiration and guidance for garbage classification for other countries.
Afficher plus [+] Moins [-]Distribution of organophosphate esters between the gas phase and PM2.5 in urban Dalian, China Texte intégral
2020
Wang, Yan | Bao, Meijun | Tan, Feng | Qu, Zhenping | Zhang, Yuwei | Chen, Jingwen
We investigated the concentrations and seasonal variations of organophosphate esters (OPEs) in the gas phase and PM₂.₅ (particulate matter with an aerodynamic diameter <2.5 μm) in an urban area of Dalian, China, as well as their gas-particle partitioning. The total concentrations of OPEs in the gas phase were in the range of 0.056–6.38 ng/m³ with the mean concentration of 0.83 ± 1.24 ng/m³, while the concentrations of OPEs in the PM₂.₅ were in the range of 0.32–3.46 ng/m³ with the mean concentration of 1.21 ± 0.67 ng/m³. Tris-(1-chloro-2-propyl) phosphate (TCIPP) was the dominant congener in the gaseous phase, followed by tris-(2-chloroethyl) phosphate (TCEP) and tri-n-butylphosphate (TNBP), whereas TCEP was the dominant species in the PM₂.₅, followed by TCIPP and triphenyl phosphate (TPHP). Seasonality was discovered for OPEs in both gas phase and PM₂.₅ with their concentrations higher in hot seasons, which may due to the temperature-driven emission or gas-particle partitioning. The PM₂.₅-bound fractions of OPEs varied significantly between seasons. Tricresyl phosphate (TMPP), tri(2-ethylhexyl) phosphate (TEHP), 2-ethylhexyl diphenyl phosphate (EHDPP), and TPHP were mostly adsorbed onto fine particles, while TNBP, TCEP, TCIPP, and tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) distributed in both gas and fine particle phases. The predicted PM₂.₅-bound fractions by Kₒₐ-based model were closer to the measurements for TCIPP, TDCIPP, and TPHP, whereas the predictions by Junge-Pankow model were closer to the measurements for TMPP and tris (2-butoxyethyl) phosphate (TBOEP). However, the predictions of both models cannot accurately match the measured gas-particle partitioning of TNBP and TCEP.
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