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  • Effects of pristine polyvinyl chloride fragments on whole body histology and protease activity in silver barb Barbodes gonionotus fry ☆
    Environ. Pollut. (IF 5.099) Pub Date : 2017-11-20
    Nicholas Romano, Munirah Ashikin, Jun Chin Teh, Fadhil Syukri, Ali Karami

    Silver barb Barbodes gonionotus fry were exposed to polyvinyl chloride (PVC) fragments at increasing concentrations of 0.2, 0.5 and 1.0 mg/L for 96 h, following which whole body histological evaluation and analysis of the digestive enzymes trypsin and chymotrypsin were performed. Whole body trypsin and chymotrypsin activities increased significantly in fish exposed to 0.5 and 1.0 mg/L PVC as compared those exposed to zero or 0.2 mg/L PVC. In fish exposed to all tested concentrations, PVCs were observed in both the proximal and distal intestine, and fish exposed to 0.5–1.0 and 1.0 mg/L PVC, respectively, and these particles were associated with localized thickening of the mucosal epithelium. No tissue damage was evident in any other internal organs or gills. This lack of damage may be attributed to the absence of contaminants associated with the PVC fragments and their relatively smooth surface. The increased whole body trypsin and chymotrypsin activities may indicate an attempt to enhance digestion to compensate for epithelial thickening of the intestine and/or to digest the plastics.

    更新日期:2017-11-20
  • Incorporating long-term satellite-based aerosol optical depth, localized land use data, and meteorological variables to estimate ground-level PM2.5 concentrations in Taiwan from 2005 to 2015 ☆
    Environ. Pollut. (IF 5.099) Pub Date : 2017-11-20
    Chau-Ren Jung, Bing-Fang Hwang, Wei-Ting Chen

    Satellite-based aerosol optical depth (AOD) is now comprehensively applied to estimate ground-level concentrations of fine particulate matter (PM2.5). This study aimed to construct the AOD-PM2.5 estimation models over Taiwan. The AOD-PM2.5 modeling in Taiwan island is challenging owing to heterogeneous land use, complex topography, and humid tropical to subtropical climate conditions with frequent cloud cover and prolonged rainy season. The AOD retrievals from the MODerate resolution Imaging Spectroradiometer (MODIS) onboard the Terra and Aqua satellites were combined with the meteorological variables from reanalysis data and high resolution localized land use variables to estimate PM2.5 over Taiwan island from 2005 to 2015. Ten-fold cross validation was carried out and the residuals of the estimation model at various locations and seasons are assessed. The cross validation (CV) R2 based on monitoring stations were 0.66 and 0.66, with CV root mean square errors of 14.0 μg/m3 (34%) and 12.9 μg/m3 (33%), respectively, for models based on Terra and Aqua AOD. The results provided PM2.5 estimations at locations without surface stations. The estimation revealed PM2.5 concentration hotspots in the central and southern part of the western plain areas, particularly in winter and spring. The annual average of estimated PM2.5 concentrations over Taiwan consistently declined during 2005–2015. The AOD-PM2.5 model is a reliable and validated method for estimating PM2.5 concentrations at locations without monitoring stations in Taiwan, which is crucial for epidemiological study and for the assessment of air quality control policy.

    更新日期:2017-11-20
  • Phytofiltration of arsenic by aquatic moss (Warnstorfia fluitans) ☆
    Environ. Pollut. (IF 5.099) Pub Date : 2017-11-20
    Arifin Sandhi, Tommy Landberg, Maria Greger

    This work investigates whether aquatic moss (Warnstorfia fluitans) originating from an arsenic (As)-contaminated wetland close to a mine tailings impoundment may be used for phytofiltration of As. The aim was to elucidate the capacity of W. fluitans to remove As from arsenite and arsenate contaminated water, how nutrients affect the As uptake and the proportion of As adsorption and absorption by the moss plant, which consists of dead and living parts. Arsenic removal from 0, 1, or 10% Hoagland nutrient solution containing 0–100 μM arsenate was followed over 192 h, and the total As in aquatic moss after treatment was analysed. The uptake and speciation of As in moss cultivated in water containing 10 μM arsenate or arsenite were examined as As uptake in living (absorption + adsorption) and dead (adsorption) plant parts. Results indicated that W. fluitans removed up to 82% of As from the water within one hour when 1 μM arsenate was added in the absence of nutrients. The removal time increased with greater nutrient and As concentrations. Up to 100 μM As had no toxic effect on the plant biomass. Both arsenite and arsenate were removed from the solution to similar extents and, independent of the As species added, more arsenate than arsenite was found in the plant. Of the As taken up, over 90% was firmly bound to the tissue, a possible mechanism for resisting high As concentrations. Arsenic was both absorbed and adsorbed by the moss, and twice as much As was found in living parts as in dead moss tissue. This study revealed that W. fluitans has potential to serve as a phytofilter for removing As from As-contaminated water without displaying any toxic effects of the metalloid.

    更新日期:2017-11-20
  • Vertical characteristics of VOCs in the lower troposphere over the North China Plain during pollution periods ☆
    Environ. Pollut. (IF 5.099) Pub Date : 2017-11-20
    Jie Sun, Yuesi Wang, Fangkun Wu, Guiqian Tang, Lili Wang, Yinghong Wang, Yuan Yang

    In recent years, photochemical smog and gray haze-fog have frequently appeared over northern China. To determine the spatial distribution of volatile organic compounds (VOC) during a pollution period, tethered balloon flights were conducted over a suburban site on the North China Plain. Statistical analysis showed that the VOCs concentrations peaked at the surface, and decreased with altitude. A rapid decrease appeared from the surface to 400 m, with concnetrations of alkanes, alkenes, aromatics and halocarbons decreasing by 48.0%, 53.3%, 43.3% and 51.1%, respectively. At heights in the range of 500–1000 m, alkenes concnetrations decline by 40.2%; alkanes and halocarbons concnetrations only decreased by 24.8% and 6.4%, respectively; and aromatics increased slightly by 5.5%. High concentrations VOCs covered a higher range of height (400 m) on heavy pollution days due to lacking of diffusion power. The VOCs concentrations decreased by 50% at 200 m on light pollution days. The transport of air mass affected the composition and concentration of high-altitude VOCs, especially on lightly polluted days. These air masses originated in areas with abundant traffic and combustion sources. Reactive aromatics (kOH>20,000 ppm−1 min−1 and kOH<20,000 ppm−1 min−1) were the main contributor to the ozone formation, accounting for 37%, on the surface on light pollution days. The contribution increased to 52% with pollution aggravated, and increased to 64% with height. The contributions of reactive aromatics were influenced by the degree of air mass aging. Under the umbrella of aging air mass, the contribution of reactive aromatics increased with height.

    更新日期:2017-11-20
  • Role of black carbon in soil distribution of organochlorines in Lesser Himalayan Region of Pakistan ☆
    Environ. Pollut. (IF 5.099) Pub Date : 2017-11-16
    Usman Ali, Rahat Riaz, Andrew James Sweetman, Kevin C. Jones, Jun Li, Gan Zhang, Riffat Naseem Malik

    Black carbon and total organic carbon (TOC) along with organochlorines (OCs) were analyzed in soils from four sampling zones of Lesser Himalayan Region based on source proximity/anthropogenic influences along the altitude. CTO-375 method was used for BC analysis while OCs were analyzed by GC-MS/MS system. BC and TOC ranged between 0.16–1.77 and 6.8–41.3 mg g−1 while those of OCPs and PCBs ranged between 0.69 and 5.77 and 0.12–2.55 ng g−1, respectively. ∑DDTs were the dominant (87.9%) among OCPs while tri- and tetra- (65.5%) homologue groups among PCBs. Hexa-PCBs, however also showed higher contribution (20.4%) in the region. Source diagnostic ratios of DDE + DDD/DDT (0.1–1.53) indicated both fresh and old input while α-HCH/γ-HCH (0.19–2.49) showed presence of lindane in the region. Higher concentration of OCs were observed in Zone C at altitudinal range of 737–975 masl that are close to the human influences and potential sources of POPs. The results of linear regression analysis revealed potential input of BC in soil distribution of OC concentrations in the region.

    更新日期:2017-11-20
  • Effective removal of hazardous trace metals from recovery boiler fly ashes
    J. Hazard. Mater. (IF 6.065) Pub Date : 2017-11-20
    Teemu Kinnarinen, Mohammad Golmaei, Eeva Jernström, Antti Häkkinen

    The objective of this study is to introduce a treatment sequence enabling straightforward and effective recovery of hazardous trace elements from recovery boiler fly ash (RBFA) by a novel method, and to demonstrate the subsequent removal of Cl and K with the existing crystallization technology. The treatment sequence comprises two stages: dissolution of most other RBFA components than the hazardous trace elements in water in Step 1 of the treatment, and crystallization of the process chemicals in Step 2. Solid-liquid separation has an important role in the treatment, due to the need to separate first the small solid residue containing the trace elements, and to separate the valuable crystals, containing Na and S, from the liquid rich in Cl and K. According to the results, nearly complete recovery of cadmium, lead and zinc can be reached even without pH adjustment. Some other metals, such as Mg and Mn, are removed together with the hazardous metals. Regarding the removal of Cl and K from the process, in this non-optimized case the removal efficiency was satisfactory: 60–70% for K when 80% of sodium was recovered, and close to 70% for Cl when 80% of sulfate was recovered.

    更新日期:2017-11-20
  • Melamine-containing polyphosphazene wrapped ammonium polyphosphate: a novel multifunctional organic-inorganic hybrid flame retardant
    J. Hazard. Mater. (IF 6.065) Pub Date : 2017-11-20
    Shuilai Qiu, Chao Ma, Xin Wang, Xia Zhou, Xiaming Feng, Richard K.K. Yuen, Yuan Hu

    To achieve superior fire safety epoxy resins (EP), a novel multifunctional organic-inorganic hybrid, melamine-containing polyphosphazene wrapped ammonium polyphosphate (PZMA@APP) with rich amino groups was prepared and used as an efficient flame retardant. Thanks to the cross-linked polyphosphazene part, PZMA@APP exhibited high flame retardant efficiency and smoke suppression to the EP composites. Thermogravimetric analysis indicated that PZMA@APP significantly enhanced the thermal stability of EP composites. The obtained sample passed UL-94 V-0 rating with 10.0 wt% addition of PZMA@APP. Notably, inclusion of incorporating PZMA@APP leads to significantly decrease on fire hazards of EP, for instance, bring about a 75.6% maximum decrease in peak heat release rate and 65.9% maximum reduction in total heat release, accompanied with lower smoke production rate and higher graphitized char layer. With regards to mechanical property, the glass transition temperature of EP/PZMA@APP10.0 was as high as 184.5 °C. In particular, the addition of PZMA@APP did not worsen the mechanical properties, compared to pure APP. It was confirmed that the participation of melamine-containing polyphosphazene could significantly enhance the quality of char layer and thereby resulting the higher flame retardant efficiency of PZMA@APP.

    更新日期:2017-11-20
  • Magnetic multi-metal co-doped magnesium ferrite nanoparticles: an efficient visible light-assisted heterogeneous Fenton-like catalyst synthesized from saprolite laterite ore
    J. Hazard. Mater. (IF 6.065) Pub Date : 2017-11-20
    Yifei Diao, Zhikai Yan, Min Guo, Xidong Wang

    Magnetic nanoparticles of multi-metal co-doped magnesium ferrite (MgFe2O4) were synthesized from saprolite laterite ore by a hydrothermal method, and firstly proposed as a heterogeneous photon-Fenton-like catalyst for degradation of Rhodamine B (RhB). The factors that influence the degradation reaction including pH value, the concentration of H2O2 and the amount of catalyst, were systematically investigated. The doped MgFe2O4 exhibited a degradation efficiency up to 96.8%, and the chemical oxygen demand (COD) and total organic carbon (TOC) removal efficiencies about 85.6% and 68.3%, respectively, under visible light illumination for 180 min. The high activity is mainly attributed to the high specific surface area of the catalyst and the synergistic interaction between photo-catalytic oxidation and Fenton-like oxidation. Moreover, the catalyst also showed good stability and recycling performance for degrading RhB. After five consecutive degradation cycles, the activity decayed no more than 10%. Compared to other catalysts prepared from pure chemical agents, the multi-metal co-doped MgFe2O4 is more competitive due to its high activity, good stability, ease of recollection, and especially the use of saprolite laterite ore as precursor. This work may provide a new avenue to synthesize efficient ferrite catalysts for degrading organic pollutants in wastewater by using natural minerals.

    更新日期:2017-11-20
  • Mercuric Ion Capturing by Recoverable Titanium Carbide Magnetic Nanocomposite
    J. Hazard. Mater. (IF 6.065) Pub Date : 2017-11-20
    Asif Shahzad, Kashif Rasool, Waheed Miran, Mohsin Nawaz, Jiseon Jang, Khaled A. Mahmoud, Dae Sung Lee

    Two-dimensional metal carbides and nitrides (MXenes) have attracted increasing attention for application in water/wastewater treatment. The functionalization of MXenes to increase their stability while demonstrating high pollutant removal can facilitate sustainable water/wastewater treatment processes. In this study, the highly stable magnetic titanium carbide (Ti3C2Tx) MXene nanocomposite (MGMX nanocomposite) was successfully synthesized through a facile hydrothermal approach and was tested for aqueous-phase adsorptive removal of mercuric ions. The synthesized MGMX nanocomposite was studied using characteristic analyses, showing high stability as revealed by zeta-potential analysis and dynamic light-scattering technique. The MGMX nanocomposite presented excellent Hg(II) removal in a wide range of pH conditions, and an exceptional maximum experimental Hg(II) uptake capacity of 1128.41 mg g−1 was observed. The adsorption behavior was investigated using the Redlich-Peterson adsorption isotherm, pseudo second-order kinetics, and thermodynamics models. In the adsorption/desorption investigation, the MGMX nanocomposite was reusable for up to five cycles of adsorption/desorption. The stability, hydrophilic nature, available adsorptive surfaces, and easy separation after reaction make the MGMX nanocomposite an efficient sorbent for the removal of toxic Hg(II) for water purification.

    更新日期:2017-11-20
  • Interaction of Human Enteric Viruses with Microbial Compounds: Implication for Virus Persistence and Disinfection Treatments
    Environ. Sci. Technol. (IF 6.198) Pub Date : 2017-11-20
    Prunelle Waldman, Alba Meseguer, Françoise Lucas, Laurent Moulin, Sébastien Wurtzer
    更新日期:2017-11-20
  • Lost, but Found with Nile Red: A Novel Method for Detecting and Quantifying Small Microplastics (1 mm to 20 μm) in Environmental Samples
    Environ. Sci. Technol. (IF 6.198) Pub Date : 2017-11-20
    Gabriel Erni-Cassola, Matthew I. Gibson, Richard C. Thompson, Joseph A. Christie-Oleza
    更新日期:2017-11-20
  • 更新日期:2017-11-20
  • The critical role of light in moderating microbial stress due to mixtures of engineered nanomaterials
    Environ. Sci.: Nano (IF 6.047) Pub Date : 2017-11-10
    Carolyn M. Wilke, Jean-François Gaillard, Kimberly A. Gray
    更新日期:2017-11-20
  • Lifetime exposure to particulate air pollutants is negatively associated with lung function in non-asthmatic children ☆
    Environ. Pollut. (IF 5.099) Pub Date : 2017-11-16
    Hung-Chang Tsui, Chi-Hsien Chen, Ying-Hsuan Wu, Hung-Che Chiang, Bing-Yu Chen, Yue Leon Guo

    Background Pulmonary function is known to be affected by acute and subacute exposure to ambient air pollution. However, the impacts of lifetime exposure to air pollution on the pulmonary function of children have been inconsistent. The present study investigated the impact of lifetime residential exposure to intermediate levels of air pollution on the pulmonary function of schoolchildren. Methods In 2011, a survey of children aged 6–15 years was conducted in 44 schools in Taiwan. Atopic history, residential history, and environmental factors were recorded. Spirograms were obtained from a random sample of children without asthma. A total of 535 girls and 481 boys without a history of asthma were enrolled. Lifetime residential exposure to air pollutants, including particulate matter with an aerodynamic diameter less than 10 μm (PM10), ozone (O3), sulfur dioxide (SO2), nitrogen dioxide (NO2), and carbon monoxide (CO), was estimated using the kriging method, based on monitored data from the Taiwan Environmental Protection Administration. Multiple linear regression was used to analyze the association between lifetime air pollution exposure and pulmonary function, after adjustment for potential confounders and recent exposure. Results After adjustment for 7-day average air pollutant levels, a 10 μg/m3 increase in PM10 was related to reductions in the forced expiratory volume in 1 s (−2.00%; 95% confidence interval [CI] −3.09% to −0.90%), forced vital capacity (−1.86%; CI: −2.96% to −0.75%), and maximal midexpiratory flow (−2.28%; CI: −4.04% to −0.51%). These associations were independent of the other pollutants. Conclusion Lifetime exposure to 25–85 μg/m3 of PM10 has negative impacts on the pulmonary function of children.

    更新日期:2017-11-20
  • Bioindicators for monitoring marine litter ingestion and its impacts on Mediterranean biodiversity ☆
    Environ. Pollut. (IF 5.099) Pub Date : 2017-11-16
    Maria Cristina Fossi, Cristina Pedà, Montserrat Compa, Catherine Tsangaris, Carme Alomar, Francoise Claro, Christos Ioakeimidis, Francois Galgani, Tatjana Hema, Salud Deudero, Teresa Romeo, Pietro Battaglia, Franco Andaloro, Ilaria Caliani, Silvia Casini, Cristina Panti, Matteo Baini

    The Mediterranean Sea has been described as one of the most affected areas by marine litter in the world. Although effects on organisms from marine plastic litter ingestion have been investigated in several oceanic areas, there is still a lack of information from the Mediterranean Sea. The main objectives of this paper are to review current knowledge on the impact of marine litter on Mediterranean biodiversity, to define selection criteria for choosing marine organisms suitable for use as bioindicator species, and to propose a methodological approach to assessing the harm related to marine litter ingestion in several Mediterranean habitats and sub-regions. A new integrated monitoring tool that would provide the information necessary to design and implement future mitigation actions in the Mediterranean basin is proposed. According to bibliographic research and statistical analysis on current knowledge of marine litter ingestion, the area of the Mediterranean most studied, in terms of number of species and papers in the Mediterranean Sea is the western sub-area as well as demersal (32.9%) and pelagic (27.7%) amongst habitats. Applying ecological and biological criteria to the most threatened species obtained by statistical analysis, bioindicator species for different habitats and monitoring scale were selected. A threefold approach, simultaneously measuring the presence and effects of plastic, can provide the actual harm and sub-lethal effects to organisms caused by marine litter ingestion. The research revealed gaps in knowledge, and this paper suggests measures to close the gap. This and the selection of appropriate bioindicator species would represent a step forward for marine litter risk assessment, and the implementation of future actions and mitigation measures for specific Mediterranean areas, habitats and species affected by marine litter ingestion.

    更新日期:2017-11-20
  • Association of diurnal temperature range with daily mortality in England and Wales: A nationwide time-series study
    Sci. Total Environ. (IF 4.9) Pub Date : 2017-11-15
    Yunquan Zhang, Minjin Peng, Lu Wang, Chuanhua Yu
    更新日期:2017-11-19
  • Effect and mechanism analysis of MnO2 on permeable reactive barrier (PRB) system for the removal of tetracycline
    Chemosphere (IF 4.208) Pub Date : 2017-11-17
    Guihua Dong, Lihui Huang, Xueyuan Wu, Chuang Wang, Yangyang Liu, Gaofeng Liu, Lisha Wang, Xiaowei Liu, Haibing Xia

    Effect of manganese dioxide (MnO2) on tetracycline (TC) removal/degradation in zero-valent iron (ZVI) based permeable reactive barrier (PRB) system was investigated. To analyze the role of MnO2, three different PRB columns packed with ZVI, ZVI and a layer of MnO2, and MnO2 were set up to investigate the removal effect and reaction mechanism of ZVI coupling with MnO2 on TC removal, respectively. The results show that the removal efficiencies of three PRB columns are 65%, 85%, and 50%, respectively. MnO2 could accelerate the transformation of Fe2+ into Fe3+ and combine with Fe3+ to degrade TC in different reaction sites in the ZVI-MnO2 PRB system. Hydroxyl radicals (·OH) were produced in this process, which contributed to about 58.3% for the TC degradation. The UV–Vis spectrum demonstrated that A ring of TC was the main reaction site for interaction with Fe3+ and the BCD rings were crucial for interactions with MnO2. On the basis of intermediates identified by LC-ESI-MS, the ring structure of TC was opened, and low-molecular-weight compounds were produced in ZVI-MnO2 PRB system.

    更新日期:2017-11-19
  • Revitalisation of metal-contaminated, EDTA-washed soil by addition of unpolluted soil, compost and biochar: Effects on soil enzyme activity, microbial community composition and abundance
    Chemosphere (IF 4.208) Pub Date : 2017-11-17
    Anela Kaurin, Zarja Cernilogar, Domen Lestan

    Soil remediation mitigates hazards from contaminants but could deprive soils of initial biota and enzymes. Historically contaminated acidic soil from Arnoldstein (Austria) and calcareous soil from Meza (Slovenia) were washed with 30 and 100 mmol kg−1 ethylenediaminetetraacetate (EDTA) to remove 78 and 60% of Pb as a main pollutant. Remediation of the Arnoldstein soil decreased urease activity and increased β-glucosidase activity, measured in a 15-week experiment. The dehydrogenase activity and microbial gene abundances were not significantly impeded compared to the original soil. Conversely, the use of a high dose of EDTA in the Meza soil, necessary for effective remediation of calcareous soils, resulted in pronouncedly decreased enzyme activities (3.2 times on average) and repressed fungal ITS and increased bacterial 16S rRNA gene abundance. Remediation shifted the microbial community composition in both soils. For revitalisation, the remediated soils were amended with compost, inocula of un-contaminated soil and (Arnoldstein soil) biochar enriched with soil extract. Amendments inconsistently affected the Arnoldstein soil: compost increased the dehydrogenase activity and altered the microbial community composition, biochar enhanced the β-glucosidase activity, and all amendments decreased the microbial abundance (1.6 times on average). In contrast, amendments efficiently revitalised the remediated Meza soil; compost and soil inoculum returned the enzyme activities back to the baseline in the original soil, increased the fungal abundance above that in the original soil and restored the microbial community composition.

    更新日期:2017-11-19
  • Cation–Pi Interaction: A Key Force for Sorption of Fluoroquinolone Antibiotics on Pyrogenic Carbonaceous Materials
    Environ. Sci. Technol. (IF 6.198) Pub Date : 2017-11-17
    Qing Zhao, Siyu Zhang, Xuejiao Zhang, Lei Lei, Wei Ma, Chuanxin Ma, Lei Song, Jingwen Chen, Bo Pan, Baoshan Xing
    更新日期:2017-11-19
  • Fluorescence and Quenching Assessment (EEM-PARAFAC) of de Facto Potable Reuse in the Neuse River, North Carolina, United States
    Environ. Sci. Technol. (IF 6.198) Pub Date : 2017-11-17
    Martha J. M. Wells, Gene A. Mullins, Katherine Y. Bell, Allegra K. Da Silva, Eileen M. Navarrete
    更新日期:2017-11-19
  • Certain Perfluoroalkyl and Polyfluoroalkyl Substances Associated with Aqueous Film Forming Foam Are Widespread in Canadian Surface Waters
    Environ. Sci. Technol. (IF 6.198) Pub Date : 2017-11-17
    Lisa A. D’Agostino, Scott A. Mabury
    更新日期:2017-11-19
  • Redox Conditions Affect Dissolved Organic Carbon Quality in Stratified Freshwaters
    Environ. Sci. Technol. (IF 6.198) Pub Date : 2017-11-17
    Tallent Dadi, Mourad Harir, Norbert Hertkorn, Matthias Koschorreck, Philippe Schmitt-Kopplin, Peter Herzsprung
    更新日期:2017-11-19
  • Heterogeneous OH Oxidation, Shielding Effects, and Implications for the Atmospheric Fate of Terbuthylazine and Other Pesticides
    Environ. Sci. Technol. (IF 6.198) Pub Date : 2017-11-17
    Joanna Socorro, Pascale S. J. Lakey, Lei Han, Thomas Berkemeier, Gerhard Lammel, Cornelius Zetzsch, Ulrich Pöschl, Manabu Shiraiwa
    更新日期:2017-11-19
  • Photooxidation of Aniline Derivatives Can Be Activated by Freezing Their Aqueous Solutions
    Environ. Sci. Technol. (IF 6.198) Pub Date : 2017-11-17
    Pablo Corrochano, Dana Nachtigallová, Petr Klán
    更新日期:2017-11-19
  • Whole-Life-Stage Characterization in the Basic Biology of Daphnia magna and Effects of TDCIPP on Growth, Reproduction, Survival, and Transcription of Genes
    Environ. Sci. Technol. (IF 6.198) Pub Date : 2017-11-17
    Han Li, Siliang Yuan, Guanyong Su, Meng Li, Qiangwei Wang, Guonian Zhu, Robert J. Letcher, Yufei Li, Zhihua Han, Chunsheng Liu
    更新日期:2017-11-19
  • Electrochemical lithium recovery and organic removal from industrial wastewater of a battery recycling plant
    Environ. Sci.: Water Res. Technol. (IF 2.817) Pub Date : 2017-11-17
    Seoni Kim, Jiye Kim, Seonghwan Kim, Jaehan Lee, Jeyong Yoon

    Lithium has become one of the most important elements due to the rapid development of mobile devices and electronics lately. There has been a steep increase in the global demand for lithium, and developing an economic supply of lithium is thereby important for battery industries. This study presents a new method for recovering lithium in wastewater from battery recycling plants, in which a considerable amount of lithium (~1900 mg/L) is discarded. There was a significant amount of organic pollutants present in the wastewater (~300 mg/L of dissolved organic carbon), and so to resolve this, we proposed an electrochemical system containing a lithium-recovering electrode (lithium manganese oxide, LMO) and an oxidant-generating electrode (boron-doped diamond, BDD) to simultaneously recover lithium and decompose organic pollutants. Repeated operation of the electrochemical system demonstrated highly efficient and reliable lithium extraction and organic material removal from wastewater. After the lithium recovery system operation, a lithium-rich solution (98.6 mol% lithium among cations) was obtained, and organic pollutants in the wastewater decreased by 65%. Furthermore, the electrochemical behavior of LMO and BDD were investigated under various operating conditions to provide useful insights for industrial applications of our LMO/BDD system.

    更新日期:2017-11-19
  • A membrane bioreactor with iron dosing and acidogenic co-fermentation for enhanced phosphorus removal and recovery in wastewater treatment
    Water Res. (IF 6.942) Pub Date : 2017-11-17
    Ruo-hong Li, Xiao-mao Wang, Xiao-yan Li

    A novel phosphorous (P) removal and recovery process using a membrane bioreactor (MBR) with ferric iron dosing and acidogenic co-fermentation was developed for municipal wastewater treatment. The very different solubility of Fe(III)-P and Fe(II)-P complex and the microbial transformation of Fe(III) to Fe(II) were utilized for P removal and recovery. By means of Fe-induced precipitation, chemical P removal was effectively achieved by an MBR with a flat-plate ceramic membrane; however, the Fe(III)-P solids accumulated in the MBR that constituted a significant fraction of the activated sludge. Anaerobic co-fermentation of the MBR sludge and food waste in a side-stream allowed the extraction of P and Fe from the sludge into the supernatant. The P in the supernatant was recovered as a fertilizer resource, while the sludge was returned to the MBR tank. The experimental results show that by adding FeCl3 at 20 mg Fe/L into the influent of domestic wastewater, about 95.6% of total P could be removed by the MBR. One fifth (20%) of the sludge in the MBR was circulated daily through the side-stream fermenters for co-fermentation with cooked rice as the model food waste. The sludge underwent acidogenesis and dissimilatory iron reduction, resulting in a drop of the pH to below 5.0 and reduction of Fe(III) to Fe(II). Owing to the high solubility of the Fe(II)-P complex, P and Fe were then dissolved and released from the sludge into the supernatant. By simply adjusting the solution pH to 8.0, the P and Fe(II) in the supernatant readily re-precipitated to form vivianite for the P recovery. Using the iron dosing MBR and side-stream sludge fermentation, an overall P recovery efficiency of 62.1% from wastewater influent can be achieved, and the problem of inorganic build-up in the MBR is effectively alleviated.

    更新日期:2017-11-17
  • Comparative evaluation of sorption kinetics and isotherms of pyrene onto microplastics
    Chemosphere (IF 4.208) Pub Date : 2017-11-17
    Wenfeng Wang, Jun Wang

    Concerns regarding microplastics pollution and their potential to concentrate and transport organic contaminants in aquatic environments are growing in recent years. Sorption of organic chemicals by microplastics may affect the distribution and bioavailability of the chemicals. Here sorption process of pyrene (Pyr), a frequently encountered polycyclic aromatic hydrocarbon in aquatic environments, on three types of mass-produced plastic particles (high-density polyethylene (PE), polystyrene (PS) and polyvinylchloride (PVC)), was investigated by comparative analysis of different sorption kinetic and isotherm models. Optimum kinetic and isotherm models were predicted by the linear least-squares regression method. The pseudo-second-order kinetic model was more appropriate in describing the entire sorption process (R2 > 0.99). Sorption rates of Pyr onto microplastics were mainly controlled by intraparticle diffusion. PE exhibited the highest affinity for Pyr, followed by PS and PVC. The sorption equilibrium data were best fitted to the Langmuir isotherm (R2 > 0.99), indicating monolayer coverage of Pyr onto the microplastics.

    更新日期:2017-11-17
  • Toxic effects and mechanism of 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) on Lemna minor
    Chemosphere (IF 4.208) Pub Date : 2017-11-17
    Nianwei Qiu, Renjun Wang, Yuan Sun, Xiushun Wang, Dacheng Jiang, Yuting Meng, Feng Zhou

    To investigate the toxic effect and mechanism of 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) in aquatic plants, in vivo and in vitro exposure to BDE-47 were conducted. After 14-d exposure to 5–20 μg/L BDE-47, the growth of Lemna minor plants was significantly suppressed, and the chlorophyll and soluble protein contents in fronds markedly decreased. Accordingly, the photosynthetic efficiency (Fv/Fm, PI) decreased. When the thylakoid membranes isolated from healthy fronds was exposed to 5–20 mg/L BDE-47 directly in vitro for 1 h, the photosynthetic efficiency also decreased significantly. In both the in vitro (5–20 μg/L) and in vivo (5–20 mg/L) experiments, BDE-47 led to an increased plasma membrane permeability. Hence, we concluded that BDE-47 had a direct toxicity to photosynthetic membranes and plasma membranes. However, direct effects on the activities of peroxidase (POD), malate dehydrogenase (MDH) and nitroreductase (NR) were not observed by adding 5–20 mg/L BDE-47 into crude enzyme extracts. The malondialdehyde (MDA) and superoxide anion radical (O2− radical dot ) contents in the BDE-47 treated fronds were higher than those in the control fronds, suggesting that L. minor can not effectively relieve reactive oxygen species (ROS). The data above indicates that BDE-47 is toxic to L. minor through acting directly on biomembranes, which induces the production of ROS and thus causes remarkable oxidative damage to cells.

    更新日期:2017-11-17
  • Simultaneous removal of NO and SO2 from flue gas by combined heat and Fe2+ activated aqueous persulfate solutions
    Chemosphere (IF 4.208) Pub Date : 2017-11-17
    Yusuf G. Adewuyi, Nana Y. Sakyi, M.A. Khan

    The use of advanced oxidation processes (AOPs) to integrate flue gas treatments for SO2, NOx and Hg0 into a single process unit is rapidly gaining research attention. AOPs are processes that rely on the generation of mainly the hydroxyl radical. This work evaluates the effectiveness of the simultaneous removal of NO and SO2 from flue gas utilizing AOP induced by the combined heat and Fe2+ activation of aqueous persulfate, and elucidates the reaction pathways. The results indicated that both SO2 in the flue gas and Fe2+ in solution improved NO removal, while the SO2 is almost completely removed. Increased temperature led to increase in NO removal in the absence and presence of both Fe2+ and SO2, and in the absence of either SO2 or Fe2+, but the enhanced NO removal due to the presence of SO2 alone dominated at all temperatures. The removal of NO increased from 77.5% at 30 °C to 80.5% and 82.3% at 50 °C and 70 °C in the presence of SO2 alone, and from 35.3% to 62.7% and 81.2%, respectively, in the presence of Fe2+ alone. However, in the presence of both SO2 and Fe2+, NO conversion is 46.2% at 30 °C, increased only slightly to 48.2% at 50 °C; but sharply increased to 78.7% at 70 °C compared to 63.9% for persulfate-only activation. Results suggest NO removal in the presence of SO2 is equally effective by heat-only or heat-Fe2+ activation as the temperature increases. The results should be useful for future developments of advanced oxidation processes for flue gas treatments.

    更新日期:2017-11-17
  • Detoxification and cellular stress responses of unionid mussels Unio tumidus from two cooling ponds to combined nano-ZnO and temperature stress
    Chemosphere (IF 4.208) Pub Date : 2017-11-17
    Halina I. Falfushynska, Lesya L. Gnatyshyna, Anna Ivanina, Inna M. Sokolova, Oksana B. Stoliar

    Bivalve mollusks from the cooling reservoirs of fuel power plants (PP) are acclimated to the chronic heating and chemical pollution. We investigated stress responses of the mussels from these ponds to determine their tolerance to novel environmental pollutant, zinc oxide nanoparticles (nZnO). Male Unio tumidus from the reservoirs of Dobrotvir and Burschtyn PPs (DPP and BPP), Ukraine were exposed for 14 days to nZnO (3.1 μM), Zn2+ (3.1 μM) at 18 °C, elevated temperature (T, 25 °C), or nZnO at 25 °C (nZnO + T). Control groups were held at 18 °C. Zn-containing exposures resulted in the elevated concentrations of total and Zn-bound metallothionein (MT and Zn-MT) in the digestive gland, an increase in the levels of non-metalated MT (up to 5 times) and alkali-labile phosphates and lysosomal membrane destabilization in hemocytes. A common signature of nZnO exposures was modulation of the multixenobiotic-resistance protein activity (a decrease in the digestive gland and increase in the gills). The origin of population strongly affected the cellular stress responses of mussels. DPP-mussels showed depletion of caspase-3 in the digestive gland and up-regulation of HSP70, HSP72 and HSP60 levels in the gill during most exposures, whereas in the BPP-mussels caspase-3 was up-regulated and HSPs either downregulated or maintained stable. BPP-mussels were less adapted to heating shown by a glutathione depletion at elevated temperature (25 °C). Comparison with the earlier studies on mussels from pristine habitats show that an integrative ‘eco-exposome’-based approach is useful for the forecast of the biological responses to novel adverse effects on aquatic organisms.

    更新日期:2017-11-17
  • Impact of plant photosystems in the remediation of benzo[a]pyrene and pyrene spiked soils
    Chemosphere (IF 4.208) Pub Date : 2017-11-17
    Anithadevi Kenday Sivaram, Logeshwaran Panneerselvan, Robin Lockington, Ravi Naidu, Mallavarapu Megharaj

    The phytoremediation potential of 14 different plant species belonging to C3 and C4 carbon fixation pathway for soils spiked with polycyclic aromatic hydrocarbons (PAHs) such as benzo[a]pyrene (B[a]P) and pyrene (PYR) was investigated. A glasshouse experiment was conducted to measure the changes in morphological, physiological, and biochemical parameters and the bioaccumulation and biodegradation ability of the plants in soils spiked with 48 and 194 mg kg−1 of B[a]P and PYR, respectively. The per cent removal efficacy of B[a]P and PYR by the tested plant species over a period of 50 days was from 6 to 26% and 14–40% respectively. The maximum removal of both B[a]P and PYR was observed in Sudan grass (C4), vetiver (C4), maize (C4), and sunflower (C3). In terms of accumulation in root and shoot, the concentration of PYR was higher in both C3 and C4 plant species when compared to B[a]P. Overall the results indicated that C4 plants were more efficient than their C3 counterparts in terms of morphological, physiological, biochemical and degradation ability of PAHs.

    更新日期:2017-11-17
  • Measuring and modeling surface sorption dynamics of organophosphate flame retardants on impervious surfaces
    Chemosphere (IF 4.208) Pub Date : 2017-11-17
    Y. Liang, X. Liu, M.R. Allen

    Understanding the sorption mechanisms for organophosphate flame retardants (OPFRs) on impervious surfaces is important to improve our knowledge of the fate and transport of OPFRs in indoor environments. The sorption processes of semivolatile organic compounds (SVOCs) on indoor surfaces are heterogeneous (multilayer sorption) or homogeneous (monolayer sorption). In this study, we adopted simplified Langmuir isotherm and Freundlich isotherm in a dynamic sink model to characterize the sorption dynamics of OPFRs on impervious surfaces such as stainless steel and made comparisons between the two models through a series of empty chamber studies. The tests involve two types of stainless steel chambers (53-L small chambers and 44-mL micro chambers) using tris(2-chloroethyl)phosphate (TCEP) and tris(1-chloro-2-propyl)phosphate (TCPP) as target compounds. Our test results show that the dynamic sink model using Freundlich isotherm can better represent the sorption process in the empty small chamber. Micro chamber test results from this study show that the sink model using both simplified Langmuir isotherm and Freundlich isotherm can well fit the measured gas-phase concentrations of OPFRs. We further applied both models and the parameters obtained to predict the gas phase concentrations of OPFRs in a small chamber with an emission source. Comparisons between model predictions and measurements demonstrate the reliability and applicability of the sorption parameters.

    更新日期:2017-11-17
  • Reviewing our Options: Managing Water-Limited Soils for Conservation and Restoration
    Land Degrad. Dev. (IF 9.787) Pub Date : 2017-11-17
    Eleanor Hobley, Noelia Garcia-Franco, Rico Hübner, Martin Wiesmeier

    The FAO considers around a quarter of global land to be degraded (FAO-ITPS, 2015). Of particular concern are threats to soils in water-limited regions, which are critical to food and economic security in countries across the globe but are under increasing pressure due to human use and climatic forcing. These soils have been used to feed and provide resources and services to human societies for millennia, with earliest land-uses dating back to pre-historic times. With the adoption of modern, frequently unsuitable agricultural practices combined with the population pressures and shifting consumption patterns, soils in water-limited regions have come under threat, resulting in degradation and in worst-case scenarios, desertification. Here we review the current state of soils in water-limited environments and provide a guide to management for conservation and restoration of these fragile soils. Options to manage specific threats to soil functionality, namely erosion, soil salinity, loss of functionality due to landscape homogenisation, degradation of soil organic matter as well as climate vulnerability are presented for specific land-uses using a whole-system approach management framework.

    更新日期:2017-11-17
  • Influence of natural regeneration on fractal features of residue microaggregates in bauxite residue disposal areas
    Land Degrad. Dev. (IF 9.787) Pub Date : 2017-11-17
    Feng Zhu, Qingyu Cheng, Shengguo Xue, Chuxuan Li, William Hartley, Chuan Wu, Tao Tian

    Bauxite residue is often physically degraded, which limits vegetation establishment on the disposal areas. Microaggregate stability is an important physical property due to its significant effect on erosion and surface runoff, however this is rarely reported for bauxite residue. Native plant encroachment on a bauxite residue disposal area in Central China has revealed that natural regeneration may ameliorate the residue and help to support plant growth. Residue samples from five different disposal ages were collected to determine microaggregate stability and identify their fractal features. Following natural regeneration, the aggregate fraction 250-50 μm increased significantly from 27.4% to 40.3%, whilst the silt+clay size aggregate fraction decreased from 58.4% to 30.7%. With increasing disposal age, the residue clay dispersion ratio (CDR) ranged from 7.7% to 22.5%, whilst aggregated silt and clay (ASC) ranged from 15.3% to 19.0% indicating a stable microaggregate structure. The single-fractal dimension (D) of the residues for different disposal ages varied from 2.2 to 2.4. The high pH and salinity of bauxite residue indicated a high value of single-fractal dimension. The multi-fractal parameters of residue microaggregates, including capacity dimension (D0), information dimension (D1) and information dimension/capacity dimension (D1/D0) decreased which resulted in homogeneity following natural regeneration. Correlation analysis revealed that both single- and multi-fractal dimensions had significant correlations with residue microaggregate stability. Our results suggested that natural regeneration may improve microaggregate stability of bauxite residue, and fractal parameters of residue microaggregates may be used to describe residue microaggregate stability and the physical condition of bauxite residue.

    更新日期:2017-11-17
  • Modulation of Nitrous Oxide (N2O) Accumulation by Primary Metabolites in Denitrifying Cultures Adapting to Changes in Environmental C and N
    Environ. Sci. Technol. (IF 6.198) Pub Date : 2017-11-16
    Octavio Perez-Garcia, Cody Mankelow, Kartik Chandran, Silas G. Villas-Boas, Naresh Singhal
    更新日期:2017-11-17
  • Reflection of Stereoselectivity during the Uptake and Acropetal Translocation of Chiral PCBs in Plants in the Presence of Copper
    Environ. Sci. Technol. (IF 6.198) Pub Date : 2017-11-16
    Shaorui Wang, Chunling Luo, Dayi Zhang, Yan Wang, Mengke Song, Zhiqiang Yu, Yujie Wang, Gan Zhang
    更新日期:2017-11-17
  • Microscale Dynamics of Oil Droplets at a Membrane Surface: Deformation, Reversibility, and Implications for Fouling
    Environ. Sci. Technol. (IF 6.198) Pub Date : 2017-11-16
    Gali Fux, Guy Z. Ramon
    更新日期:2017-11-17
  • A review of sanitation technologies to achieve multiple sustainable development goals that promote resource recovery
    Environ. Sci.: Water Res. Technol. (IF 2.817) Pub Date : 2017-11-03
    Kevin D. Orner, James R. Mihelcic
    更新日期:2017-11-17
  • Emerging investigator series: the effect of wildfire on streamwater mercury and organic carbon in a forested watershed in the southeastern United States
    Environ. Sci.: Processes Impacts (IF 2.592) Pub Date : 2017-11-03
    Allison M. Jensen, Todd M. Scanlon, Ami L. Riscassi
    更新日期:2017-11-17
  • Droplet distribution and airborne bacteria in an experimental shower unit
    Water Res. (IF 6.942) Pub Date : 2017-11-16
    C.E. Estrada-Perez, K.A. Kinney, J.P. Maestre, Y.A. Hassan, M.D. King

    Although human exposure to water aerosols is common in residential showers, the droplet distribution patterns generated in showers are not well understood nor is the bacteria released during shower operation. In this study, a two-phase flow Particle Tracking Velocimetry (PTV) algorithm was successfully used to characterize the spatial spray pattern and velocity field in two experimental showers (one low-flow and one high-flow). In addition, the airborne bacteria present in the shower over nearly 5 months of controlled operation was determined for both showers. The results indicate that the droplet velocity out of the low-flow showerhead (which had fewer orifices) was significantly higher than that out of the high-flow showerhead resulting in a higher aerosol number concentration in the low-flow shower and more consistent wetting of the shower wall. Both showerheads generated droplets in the respirable range and genera of potential health concern were observed in the shower aerosols measured both prior to and following shower operation. The study provides one of the first visualizations of droplet spray patterns in residential showers and provides insight into the airborne bacteria present in showers.

    更新日期:2017-11-17
  • Construction of plasmonic Ag modified phosphorous-doped ultrathin g-C3N4 nanosheets/BiVO4 photocatalyst with enhanced visible-near-infrared response ability for ciprofloxacin degradation
    J. Hazard. Mater. (IF 6.065) Pub Date : 2017-11-15
    Yaocheng Deng, Lin Tang, Chengyang Feng, Guangming Zeng, Jiajia Wang, Yaoyu Zhou, Yani Liu, Bo Peng, Haopeng Feng

    To realize the full utilization of solar energy, the design of highly efficient photocatalyst with improved visible-near-infrared photocatalysis performance has attracted great attentions for environment pollutant removal. In this work, we rationally employed the surface plasmon resonance effect of metallic Ag in the phosphorus doped ultrathin g-C3N4 nanosheets (PCNS) and BiVO4 composites to construct a ternary Ag@PCNS/BiVO4 photocatalyst. It was applied for the photodegradation of ciprofloxacin (CIP), exhibiting 92.6% removal efficiency under visible light irradiation (λ > 420 nm) for 10 mg/L CIP, and presenting enhanced photocatalytic ability than that of single component or binary nanocomposites under near-infrared light irradiation (λ > 760 nm). The improved photocatalytic activity of the prepared Ag@PCNS/BiVO4 nanocomposite can be attributed to the synergistic effect among the PCNS, BiVO4 and Ag, which not only improves the visible light response ability and hinders the recombination efficiency of the photogenerated electrons and holes, but also retains the strong the redox ability of the photogenerated charges. According to the trapping experiment and ESR measurements results, radical dot OH, h+ and radical dot O2− all participated in the photocatalytic degradation process. Considering the SPR effect of metallic Ag and the established local electric field around the interfaces, a dual Z-scheme electrons transfer mechanism was proposed.

    更新日期:2017-11-17
  • Responses in Ozone and Its Production Efficiency Attributable to Recent and Future Emissions Changes in the Eastern United States
    Environ. Sci. Technol. (IF 6.198) Pub Date : 2017-11-16
    Lucas R. F. Henneman, Huizhong Shen, Cong Liu, Yongtao Hu, James A. Mulholland, Armistead G. Russell

    Ozone production efficiency (OPE), a measure of the number of ozone (O3) molecules produced per emitted NOX (NO + NO2) molecule, helps establish the relationship between NOX emissions and O3 formation. We estimate long-term OPE variability across the eastern United States using two novel approaches: an observation-based empirical method and a chemical transport model (CTM) method. The CTM approach explicitly controls for differing O3 and NOX reaction product (NOZ) deposition rates and separately estimates OPEs from on-road mobile and electricity generating unit sources across a broad spatial scale. We find lower OPEs in urban areas and that average July OPE increased over the eastern United States domain between 2001 and 2011 from 11 to 14. CTM and empirical approaches agree at low NOZ concentrations, but CTM OPEs are greater than empirical OPEs at high NOZ. Our results support that NOX emissions reductions become more effective at reducing O3 at lower NOZ concentrations. Electricity generating unit OPEs are higher than mobile OPEs except near emissions locations, meaning further utility NOX emissions reductions will have greater per unit impacts on O3 regionally.

    更新日期:2017-11-17
  • Species Sensitivity Distributions for Nonylphenol to Estimate Soil Hazardous Concentration
    Environ. Sci. Technol. (IF 6.198) Pub Date : 2017-11-16
    Jin Il Kwak, Jongmin Moon, Dokyung Kim, Rongxue Cui, Youn-Joo An
    更新日期:2017-11-17
  • SPATIAL PATTERNS OF SEDIMENT CONNECTIVITY IN TERRACED LANDS: ANTHROPOGENIC CONTROLS OF CATCHMENT SENSITIVITY
    Land Degrad. Dev. (IF 9.787) Pub Date : 2017-11-16
    Aleix Calsamiglia, Josep Fortesa, Julián García-Comendador, Manuel E. Lucas-Borja, Adolfo Calvo-Cases, Joan Estrany

    In recent decades the dynamics of global change in developed countries has led to significant alterations in the hydrological and sediment dynamics of terraced land. Agricultural terraces were built to control overland flow and prevent erosion, acting as buffers and barriers throughout the sediment cascading system. Their abandonment and degradation increase the sensitivity of the catchment, promoting the collapse of dry-stone walls and the reworking of stored sediment. In this study, a geomorphometric Index of Connectivity (IC) –derived from high-resolution LiDAR data (0.9 pt m-2, RMSE < 0.2 m)– analysed the spatial patterns of structural connectivity in a small Mediterranean catchment (4.8 km2) characterized by a massive presence of terraces (37% of the surface area). The morphological characteristics of these anthropogenic features generated a dual effect: (1) general disconnectivity between different compartments of the catchment and (2) concentration of water and sediment flows along preferential pathways promoted by a cascade effect of collapse within the terraced areas. The fieldwork found that 73% of wall collapses were located on these pathways that showed high IC values (>Q8). This spatial matching was related to feedback dynamics between structural and functional connectivity, in which the failure of walls increases the concentration of runoff, which in turn accelerates the hydraulic processes causing their collapse. Identifying the most connected pathways within the most vulnerable structures in an integrated analysis could be a cost-effective strategy for establishing priority areas for the management of terraced lands.

    更新日期:2017-11-17
  • Subcellular distribution and biotransformation of phenanthrene in pakchoi after inoculation with endophytic Pseudomonas sp. as probed using HRMS coupled with isotope-labeling
    Environ. Pollut. (IF 5.099) Pub Date : 2017-11-15
    Kai Sun, Mussie Y. Habteselassie, Juan Liu, Shunyao Li, Yanzheng Gao

    Contamination of food-crops with polycyclic aromatic hydrocarbons (PAHs) poses a grave concern to food safety, especially when PAHs are internalized. We have demonstrated in our previous study that inoculation of crop with a phenanthrene-degrading endophytic Pseudomonas sp. Ph6-gfp could overcome this problem. Here, the subcellular distribution and biotransformation mechanism of phenanthrene in pakchoi (Brassica chinensis L.) seedlings with inoculation of Ph6-gfp were further investigated both in vitro and in vivo. The possible biotransformation products of phenanthrene were identified by high-resolution mass spectrometry (HRMS) coupled with 13C2-phenanthrene labeling. Results indicated that Ph6-gfp colonized pakchoi interior and reduced the content of phenanthrene in different cell compartments. Notably, the inoculation hindered the subcellular distribution of phenanthrene from intercellular space to subcellular fractions (i.e., cell wall, cell membrane, cell solution, and cell organelles), likely resulting from the interception and biodegradation of phenanthrene by the bacterium between the cell wall and intercellular space. Additionally, the conjugation reactions of phenanthrene-metabolites and endogenous plant compounds were enhanced as a result of the inoculation. We propose that endophytic degradation, plant metabolism, and conjugation reaction are the three possible biotransformation mechanisms that could account for the changes in phenanthrene inside the plant cell compartments. This is the first observation of endophytic bacteria (EB)-enhanced biotransformation and conjugation of phenanthrene in pakchoi at the subcellular level, which drive novel insights in regulating food-crop contamination with endophytes in PAH-contaminated matrices.

    更新日期:2017-11-16
  • Sensitivity of the early life stages of a mayfly to fine sediment and orthophosphate levels
    Environ. Pollut. (IF 5.099) Pub Date : 2017-11-15
    Nicholas C. Everall, Matthew F. Johnson, Paul Wood, Lauren Mattingley

    The ecological effects of interacting stressors within lotic ecosystems have been widely acknowledged. In particular, the ecological effects of elevated fine sediment inputs and phosphate have been identified as key factors influencing faunal community structure and composition. However, while knowledge regarding adult and larval life stage responses to environmental stressors has grown, there has been very limited research on their eggs. In this study, the eggs of the mayfly Serratella ignita (Ephemerellidae: Ephemeroptera) were collected and incubated in laboratory aquaria to hatching under differing concentrations of inert suspended sediment (SS) and orthophosphate (OP), individually and in combination. Results indicate that SS and OP have greater effects on egg hatching in combination than when either were considered in isolation. SS displayed a greater effect on egg survival than OP in isolation or when OP was added to elevated SS treatments. Egg mortality in control treatments was around 6% compared to 45% in treatments with 25 mg l−1 SS and 52% in 0.3 mg l−1 OP treatments. Even relatively modest levels of each stressor (10 mg l−1 SS; 0.1 mg l−1 OP), below national legal thresholds, had significant effects on egg survival to hatching. The results support calls for legal levels of SS to be reassessed and suggest that more research is required to assess the impacts of pollution on invertebrate egg development given their different sensitivity and exposure pathways compared to other life stages.

    更新日期:2017-11-16
  • Impacts of environmental factors on the whole microbial communities in the rhizosphere of a metal-tolerant plant: Elsholtzia haichowensis Sun
    Environ. Pollut. (IF 5.099) Pub Date : 2017-11-15
    Songqiang Deng, Tan Ke, Longtai Li, Shenwen Cai, Yuyue Zhou, Yue Liu, Limin Guo, Lanzhou Chen, Dayi Zhang

    Rhizospheric microbes play important roles in plant growth and heavy metals (HMs) transformation, possessing great potential for the successful phytoremediation of environmental pollutants. In the present study, the rhizosphere of Elsholtzia haichowensis Sun was comprehensively studied to uncover the influence of environmental factors (EFs) on the whole microbial communities including bacteria, fungi and archaea, via quantitative polymerase chain reaction (qPCR) and high-throughput sequencing. By analyzing molecular ecological network and multivariate regression trees (MRT), we evaluated the distinct impacts of 37 EFs on soil microbial community. Of them, soil pH, HMs, soil texture and nitrogen were identified as the most influencing factors, and their roles varied across different domains. Soil pH was the main environmental variable on archaeal and bacterial community but not fungi, explaining 25.7%, 46.5% and 40.7% variation of bacterial taxonomic composition, archaeal taxonomic composition and a-diversity, respectively. HMs showed important roles in driving the whole microbial community and explained the major variation in different domains. Nitrogen (NH4-N, NO3-N, NO2-N and TN) explained 47.3% variation of microbial population composition and 15.9% of archaeal taxonomic composition, demonstrating its influence in structuring the rhizospheric microbiome, particularly archaeal and bacterial community. Soil texture accounted for 10.2% variation of population composition, 28.9% of fungal taxonomic composition, 19.2% of fungal a-diversity and 7.8% of archaeal a-diversity. Rhizosphere only showed strong impacts on fungi and bacteria, accounting for 14.7% and 4.9% variation of fungal taxonomic composition and bacterial a-diversity. Spatial distance had stronger influence on bacteria and archaea than fungi, but not as significant as other EFs. For the first time, our study provides a complete insight into key influential EFs on rhizospheric microbes and how their roles vary across microbial domains, giving a hand for understanding the construction of microbial communities in rhizosphere.

    更新日期:2017-11-16
  • Inorganic sulfur and mercury speciation in the water level fluctuation zone of the Three Gorges Reservoir, China: The role of inorganic reduced sulfur on mercury methylation
    Environ. Pollut. (IF 5.099) Pub Date : 2017-11-15
    Jiang Liu, Tao Jiang, Feiyue Wang, Jinzhong Zhang, Dingyong Wang, Rong Huang, Deliang Yin, Zeyan Liu, Jinzhu Wang

    The water level fluctuation zone (WLFZ) of the Three Gorges Reservoir (TGR) in China is a unique geomorphological unit that undergoes annual flooding and drying alternation cycle. The alternating redox conditions within the WLFZ are expected to result in dynamic cycling of reduced sulfur species, which could affect mercury (Hg) methylation due to the high affinity of reduced sulfur species to both inorganic divalent mercury (Hg(II)i) and methylmercury (MeHg). Variations of inorganic sulfur species (measured as acid volatile sulfide, chromium reductive sulfur, elemental sulfur, and water-soluble sulfate), total mercury (THg) and MeHg were studied at two typical WLFZ sites in the TGR from July 2015 to June 2016. Whereas the water-soluble sulfate contents stayed essentially constant, the reduced inorganic sulfur contents varied greatly as the water level changed. Compared with the control soils, the MeHg contents in the WLFZ soils increased, suggesting that water level fluctuations accelerated the methylation process of Hg(II)i. In situ Hg(II)i-methylation also appeared to occur in the sub-layer of the drained sediment during the draw-down season. The significant correlation between MeHg and elemental sulfur (S(0)) further suggests that polysulfides may have played a role in Hg(II)i-methylation by increasing the bioavailable Hg(II)i content in the WLFZ of the TGR.

    更新日期:2017-11-16
  • Toxicity-associated changes in the invasive cyanobacterium Cylindrospermopsis raciborskii in response to nitrogen fluctuations
    Environ. Pollut. (IF 5.099) Pub Date : 2017-11-15
    Yiming Yang, Youxin Chen, Fangfang Cai, Xiang Liu, Yilang Wang, Renhui Li

    The cyanobacterium Cylindrospermopsis raciborskii is of particular concern due to its ability to fix nitrogen (N), sporadic bloom, potential toxicity and apparent invasiveness. However, the toxicity associated behavior and response of toxic C. raciborskii under N fluctuations in water have been poorly investigated. The present study initiated based on the field survey in which Cylindrospermopsis species was found to have a high fitness under nitrate concentrations fluctuating from 0.02 mg L−1 to 2.90 mg L−1 in Chinese freshwater lakes. Examination on the role of short-term N fluctuations was conducted in two C. raciborskii strains which were exposed to a range of N concentrations supplied in two patterns, namely one-time pattern and ten-time pattern in which the equal amount of N was divided into ten-time accretions. The results showed the growth of both strains were not vulnerable to the transient nutrient fluctuations. The toxic strain showed considerable toxicological flexibility with the highest yield of cylindrospermopsin (CYN) obtained in the absence of N and the lowest in full medium. Generally, larger amounts of total CYN were observed at lower N levels, indicating that N deficiency promoted the intracellular accumulation and simultaneously restrained the extracellular release of CYN. Furthermore, CYN production was significantly different in two N supply patterns. The maximum quotas of intracellular and extracellular CYN in one-time pattern were respectively 2.79–3.53 and 3.94–7.20 times higher compared to the ten-time pattern. To our knowledge, our results are the first evidence of toxicity variations of C. raciborskii to the impermanent N fluctuations, shedding new light on its toxicological plasticity.

    更新日期:2017-11-16
  • Effects of red earthworms (Eisenia fetida) on leachability of lead minerals in soil
    Environ. Pollut. (IF 5.099) Pub Date : 2017-11-14
    Armin Kavehei, Grant C. Hose, Damian B. Gore

    Contamination of soils by metals and metalloids is an important environmental problem in many residential and industrial sites around the world. Lead is a common contaminant, which enters the soil through mining, industrial activities and waste disposal. A range of technologies can be used to remediate soil lead, however most remediation technologies adversely affect the environment and particularly soil biota. We have assessed the efficacy of vermiremediation (the use of earthworms for remediation) to reduce water extractable lead concentrations in soil. Earthworms were introduced to a sandy soil spiked with the common lead minerals cotunnite (PbCl2), cerussite (PbCO3), massicot (PbO) or galena (PbS) at 1000 mg (Pb) kg−1. Lead concentrations in pore water extracted during the experiment were not significantly different in contaminated soil with and without worms. However, concentrations of lead in water from a deionised water extraction (washing) of contaminated soil were significantly lower in soil with earthworms than in soil without. Earthworms accumulated on average (±1 standard deviation) 276 ± 118, 235 ± 66, 241 ± 58 and 40 ± 30 mg kg−1 (dry weight of earthworms) of lead in their bodies, in PbCl2, PbCO3, PbO and PbS-dosed soils, respectively. During the experiment, earthworms lost weight in all contaminated soils, except those containing PbS.

    更新日期:2017-11-16
  • Reproductive effects linked to DNA methylation in male zebrafish chronically exposed to environmentally relevant concentrations of di-(2-ethylhexyl) phthalate
    Environ. Pollut. (IF 5.099) Pub Date : 2017-11-14
    Yan-Bo Ma, Pan-Pan Jia, Muhammad Junaid, Li Yang, Chun-Jiao Lu, De-Sheng Pei

    Di-(2-ethylhexyl) phthalate (DEHP) possesses the potential to interfere with the male reproductive endocrine system in mammals; however, its reproductive toxicity in male zebrafish and associated epigenetic studies have not been explored. In this study, three-month-old male zebrafish were exposed to environmentally relevant concentrations of DEHP (0, 10, 33 and 100 μg/L) for 3 months, and then the impact on the reproduction of males and the underlying mechanism were investigated. Histological testing showed that an exposure concentration of 100 μg/L DEHP significantly inhibited spermatogenesis, with an associated decline in capability to fertilize untreated oocytes. Electron microscopic examinations also revealed noticeable damage to the testicular ultrastructure at the 100 μg/L DEHP exposure level. In addition, exposure to 33 and 100 μg/L of DEHP resulted in a decline of circulating testosterone (T) and an increase in the level of 17β-estradiol (E2), both of which were possibly derived from the downregulation of cyp17a1 and hsd17b3 genes and the upregulation of the cyp19a1a gene in the gonads. The DNA methylation statuses of these genes were altered within their promoter regions. A significant increase in global DNA methylation in both the male testes and their offspring larvae was observed at higher exposure concentration of DEHP. Our findings demonstrate that exposure to environmentally relevant concentrations of DEHP can damage the testes, disturbe the sex hormones production, and inhibite spermatogenesis, which ultimately impairs the reproduction of male zebrafish.

    更新日期:2017-11-16
  • Spatial and temporal variability of bacterial indicators and pathogens in six California reservoirs during extreme drought
    Water Res. (IF 6.942) Pub Date : 2017-11-16
    Melissa L. Partyka, Ronald F. Bond, Jennifer A. Chase, Edward R. Atwill

    California has one of the largest systems of surface water reservoirs in the world, providing irrigation water to California's agriculturally productive Central Valley. Irrigation water is recognized as a vehicle for the microbial contamination of raw produce and must be monitored according to new federal regulation. The purpose of this study was to further understanding of the variability of fecal indicator bacteria (Escherichia coli and fecal coliforms) and pathogens (E. coli O157:H7, Non-O157 shiga toxin-producing E. coli and Salmonella) along both horizontal and vertical profiles within California reservoirs. Monthly sampling was conducted in six reservoirs located in the foothills of the Western Sierra Nevada during the summer irrigation season and extreme drought conditions of 2014 (n = 257). Concentrations of fecal indicator bacteria were highly variable between reservoirs (p < 0.05) and along the horizontal profile (p < 0.001) from upstream to downstream, with higher concentrations typically found outside of the reservoirs than within. Though many of the reservoirs were thermally stratified, bacterial concentrations were not associated with water temperature (p > 0.05) or any one particular depth strata (p < 0.05). However, prevalence of Salmonella and non-O157 STEC (16/70 and 9/70 respectively) was higher in the deep strata than in mid or surface layers. Water quality outcomes were We found no statistical association between samples collected downstream of reservoirs and those from the reservoirs themselves. Continued monitoring and modeling of both bacterial indicators and enteric pathogens are critical to our ability to estimate the risk of surface irrigation water supplies and make appropriate management decisions.

    更新日期:2017-11-16
  • Toxic Effects of Different Types of Zinc Oxide Nanoparticles on Algae, Plants, Invertebrates, Vertebrates and Microorganisms
    Chemosphere (IF 4.208) Pub Date : 2017-11-16
    Jing Hou, Yazhou Wu, Xin Li, Benben Wei, Shiguo Li, Xiangke Wang

    Concerns about the potential environmental risks of zinc oxide nanoparticles (ZnO NPs) are becoming an important issue because of their rapid growth in different fields. ZnO NPs are inevitably released in the environment during the production, transport, use and disposal process. Therefore, it is necessary to understand their toxicities and mode of actions. This review summarizes the toxic effects of ZnO NPs with different properties and exposed conditions on different species. The mechanisms of ZnO NPs on living organisms could be mainly attributed to one or more of the following aspects: the physical damage of direct contact, the dissolved zinc ions and the ROS-mediated mechanism. This paper systematically reviews the toxic effects of ZnO NPs on organisms and puts forward the existing problems, which are helpful for the safe and efficient use of ZnO NPs, providing the basis for further study of the toxic effects of ZnO NPs and establishing a comprehensive and safe evaluation system.

    更新日期:2017-11-16
  • Tree bark as a bioindicator of the presence of scandium, yttrium and lanthanum in urban environments
    Chemosphere (IF 4.208) Pub Date : 2017-11-16
    V. Minganti, Drava G

    Although rare earth elements (REEs) are important in modern industry, few processes use them, so the possibility of these elements being dispersed in the environment is small. For this reason, there are few studies on their presence in urban environments. REEs exhibit similar chemical properties, and Group 3 elements may be used as indicators of the presence of other REEs in the environment. Tree bark is a suitable collector of airborne trace elements and has been successfully used as a bioindicator. In this study, samples of holm oak bark were collected from three sampling sites subjected to different anthropic pressures (one area is far from human influence, while the other two sites are urban areas characterized by different types of human impact). The reference area is significantly different from urban areas where the concentrations measured are up to 5 times higher (Y) than the reference area. The differences between the two urban areas are also significant. The presence of industrial activities causes a 50% higher exposition of the population with respect to an urban area where only residential activities are present. In the case of La, there is no significant difference between the reference and the residential areas, while the industries are responsible for higher La concentrations (0.9 μg g-1vs. 0.4‒0.6 μg g-1). The availability of samples, due to the wide distribution of trees in urban environments, makes possible the production of maps indicating the sources of these elements and highlighting areas which are critical for certain atmospheric pollutants.

    更新日期:2017-11-16
  • Occurrence of benzothiazole, benzotriazole and benzenesulfonamide derivates in outdoor air particulate matter samples and human exposure assessment
    Chemosphere (IF 4.208) Pub Date : 2017-11-16
    Alba Maceira, Rosa Maria Marcé, Francesc Borrull

    Benzothiazole (BTHs), benzotriazole (BTRs) and benzenesulfonamide (BSAs) derivates are high production volume chemicals and they are used in several industrial and household applications, therefore it is expected their occurrence in various environments, especially water and air. In this study we developed a method based on gas chromatography-mass spectrometry (GC-MS) combined with pressurised liquid extraction (PLE) to simultaneously determine four BTR, five BTH and six BSA derivates in the particulate matter (PM10) of outdoor air samples collected in quartz fibre filters (QFFs). To the best of our knowledge, this is the first time these compounds have been determined in open ambient environments. Under optimised conditions, method recoveries at the lower and upper concentration levels (0.8 and 4.2 ng m−3) ranged from 70 to 120%, except for 1-H-benzothiazole and 2-chlorobenzothiazole, which were about 50%. The repeatability of the method was usually below 20% (n = 3, %RSD) for both concentration levels. This method enables the contaminants to be detected at pg m−3 concentration levels. Several samples from two different sites influenced by local industries showed that BTRs, followed by BTHs, were the most detected compounds, whereas BSAs were hardly found. The most frequently determined compounds were 1-H-benzothiazole, 2-chlorobenzothiazole, 1-H-benzotriazole, 2-hydroxibenzothiazole, 5,6-dimethyl-1-H-benzotriazole and the isomers 4- and 5-methyl-1-H-benzotriazole. With the concentrations found, the human exposure assessment and health risk characterization via ambient inhalation were also evaluated taking into account different subpopulation groups classified by age for the two sampling points.

    更新日期:2017-11-16
  • Sample handling and data processing for fluorescent excitation-emission matrix (EEM) of dissolved organic matter (DOM)
    Chemosphere (IF 4.208) Pub Date : 2017-11-16
    Minkyu Park, Shane A. Snyder

    In environmental engineering and science, fluorescent excitation-emission matrix (EEM) has increasingly been utilized to characterize chromophoric dissolved organic matter (CDOM). This study aims to delineate data processing, including calculation of total fluorescence (TF) which is an emerging water quality parameter often used as a surrogate for trace organic contaminant (TOrC) removal by advanced water treatment processes. In addition, sample handling procedures such as storage, use of preservatives, and oxidant quenching agents were evaluated. In this study, three antimicrobial preservatives were tested: sodium azide, sodium omadine, and thymol. All the tested preservatives altered optical properties of samples, and were therefore not suitable for the preservation of EEM samples. Without preservative, storage of samples at 4 °C maintained TF within 7.5% of its original value for 21 days, while TF of samples stored at the room temperature more drastically changed (up to 15%). The impacts of three oxidant quenching agents including ascorbic acid, sodium bisulfite, and sodium thiosulfate on EEM were also tested. Among the quenching agents, sodium bisulfite was found to be suitable since it little influenced optical properties of samples while the other two were not favorable due to interference. We also scrutinized the use of TF as surrogate to monitor micropollutant rejection by nanofiltration membrane.

    更新日期:2017-11-16
  • Degradation of diethyl phthalate (DEP) by UV/persulfate: An experiment and simulation study of contributions by hydroxyl and sulfate radicals
    Chemosphere (IF 4.208) Pub Date : 2017-11-16
    Ziying Wang, Yisheng Shao, Naiyun Gao, Xian Lu, Na An

    Degradation of diethyl phthalate (DEP) by ultraviolet/persulfate (UV/PS) process at different reaction conditions was evaluated. DEP can be degraded effectively via this process. Both tert-butyl (TBA) and methanol (MeOH) inhibited the degradation of DEP with MeOH having a stronger impact than TBA, suggesting sulfate radical ( Image 1 ) and hydroxyl radical (HO radical dot ) both existed in the reaction systems studied. The second-order rate constants of DEP reacting with Image 1 and HO radical dot were calculated to be View the MathML source ( 6.4 ± 0.3 ) × 10 7 M−1s−1 and View the MathML source ( 3.7 ± 0.1 ) × 10 9 M−1s−1, respectively. To further access the potential degradation mechanism in this system, the pseudo-first-order rate constants (ko) and the radical contributions were modeled using a simple steady-state kinetic model involving Image 1 and HO radical dot . Generally, HO radical dot had a greater contribution to DEP degradation than Image 1 . The ko of DEP increased as PS dosages increased when PS dosages were below 1.9 mM. However, it decreased with increasing initial DEP concentrations, which might be due to the radical scavenging effect of DEP. The ko values in acidic conditions were higher than those in alkaline solutions, which was probably caused by the increasing concentration of hydrogen phosphate (with higher scavenging effects than dihydrogen phosphate) from the phosphate buffer as pH values rose. Natural organic matter and bicarbonate dramatically suppressed the degradation of DEP by scavenging Image 1 and HO radical dot . Additionally, the presence of chloride ion (Cl−) promoted the degradation of DEP at low Cl− concentrations (0.25–1 mM). Finally, the proposed degradation pathways were illustrated.

    更新日期:2017-11-16
  • Neurobehavioral assessment of rats exposed to pristine polystyrene nanoplastics upon oral exposure
    Chemosphere (IF 4.208) Pub Date : 2017-11-16
    Mohammad Rafiee, Leila Dargahi, Akbar Eslami, Elmira Beirami, Mahsa Jahangiri-rad, Siamak Sabour, Fatemeh Amereh

    The increasing use of plastics has raised concerns about pollution of freshwater by these polymeric materials. Knowledge about their potential effects on environmental and public health is limited. Recent publications have suggested that the degradation of plastics will result in the release of nano-sized plastic particles to the environment. Therefore, it is of utmost importance to gain knowledge about whether and how nanoplastics affect living organisms. The present study aimed to analyse potential neurobehavioral effects of polystyrene nanoparticles (PS-NPs) after long-term exposure on rat. Potential effects of PS-NPs were investigated using four test dosages (1, 3, 6, and 10 mg PS-NPs/kg of body weight/day) administrated orally with adult Wistar male rats for five weeks. Neurobehavioral tests were chosen to assess a variety of behavioral domains. Particle diameters in test suspensions were determined through dynamic light scattering and showed an average hydrodynamic diameter of approximately 38.92 nm. No statistically significant behavioral effects were observed in all tests performed (p > 0.05). In the elevated plus maze, PS-NPs-exposed rats showed greater number of entries into open arms compared to controls. Also, PS-NPs had no significant influence on body weight of animals. Taking into account the subtle and transient nature of neurobehavioral consequences, however, these results underline the possibility of even pristine plastic nanoparticles to induce behavioral alteration in the rest of the food web, including for marine biota and humans. Indeed even though studied neurobehavioral effects in our study was not statistically significant, the observed subtle effects may be clinically considerable.

    更新日期:2017-11-16
  • Electro-oxidation of Ofloxacin antibiotic by dimensionally stable Ti/Ruo2 anode: Evaluation and mechanistic approach
    Chemosphere (IF 4.208) Pub Date : 2017-11-16
    Ravneet Kaur, Jai Prakash Kushwaha, Neetu Singh

    Present study investigates the potential of Ti/RuO2 electrode for degradation and mineralization of Ofloxacin (OFLX) antibiotic from synthetic wastewater by electro-oxidation (EO) method, not reported earlier. Effects of various EO parameters such as applied current (I), initial pH, initial OFLX concentration (C0) and supporting electrolyte concentration on %OFLX removal efficiency and %TOC removal efficiency were systematically studied and reported. Decay kinetics of OFLX by varying C0 and applied I were also studied. Additionally, Mineralization current efficiency and specific energy consumption of OFLX mineralization were evaluated. Moreover, mode of oxidation method involved (direct and/or indirect oxidation) was also explored. Major OFLX transformation products during EO were identified using UPLC-Q-TOF-MS, and possible degradation reaction mechanism was proposed. Furthermore, operating cost analysis was performed to check the economic feasibility of the EO process. The optimum pH and current were found to be 6.8 (natural pH of OFLX wastewater) and 1 A, respectively. Mineralization current efficiency decreased from 7.8% to 4.9% with increase in I value from 0.25 to 1 A. ≈80% of OFLX removal in 30 min of electrolysis and 46.3% TOC removal in 240 min of electrolysis at I = 1 A were observed. Pseudo-first-order kinetic model best fitted the experimental data showing R2 value ≈ 0.99 for all the Co and applied I studied.

    更新日期:2017-11-16
Some contents have been Reproduced with permission of the American Chemical Society.
Some contents have been Reproduced by permission of The Royal Society of Chemistry.
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