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Comparing black carbon types in sequestering polybrominated diphenyl ethers (PBDEs) in sediments Texto completo
2014
Jia, Fang | Gan, Jay
Polybrominated diphenyl ethers (PBDEs) are widely found in sediments, especially congeners from the penta-BDE formula. Due to their strong affinity for black carbon (BC), bioavailability of PBDEs may be decreased in BC-amended sediments. In this study, we used a matrix-SPME method to measure the freely dissolved concentration (Cfree) of PBDEs as a parameter of their potential bioavailability and evaluated the differences among biochar, charcoal, and activated carbon. Activated carbon displayed a substantially greater sequestration capacity than biochar or charcoal. At 1% amendment rate in sediment with low organic carbon (OC) content (0.12%), Cfree of six PBDEs was reduced by 47.5–78.0%, 47.3–77.5%, and 94.1–98.3% with biochar, charcoal, and activated carbon, respectively, while the sequestration was more limited in sediment with high OC content (0.87%). Therefore, it is important to consider the type and properties of the BC and the sediment in BC-based remediation or mitigation.
Mostrar más [+] Menos [-]Levels, distribution and human exposure of new non-BDE brominated flame retardants in the indoor dust of China Texto completo
2014
Qi, Hong | Li, Wen-Long | Liu, Li-Yan | Zhang, Zi-Feng | Zhu, Ning-Zheng | Song, Wei-Wei | Ma, Wanli | Li, Yi-Fan
Indoor environment is an important source of human exposure to several toxicants, such as brominated flame retardants. This study presents the concentrations of 22 Non-BDE brominated flame retardants (NBFRs) in 81 indoor dust samples from 23 provinces across China in the winter of 2010. The concentrations of ΣNBFRs ranged from 6.3 to 20,000 ng/g, with a median concentration of 720 ng/g. DBDPE was the dominated compound, followed by HBCD and BEHTBP. Significant differences of concentrations were found between samples from rural and urban areas, and between family and public houses, indicating different applications of NBFRs. The geographical distribution of NBFRs highlighted several hotspots in North China, suggesting the influence of room temperature (heating). The exposure via dust ingestion of NBFRs was 3.8–14 times higher than that of dermal absorption. The toddlers demonstrated the highest exposure dose (9.6 ng/kg-bw/day) of NBFRs through indoor dust among all life stages.
Mostrar más [+] Menos [-]Comparative study of polycyclic aromatic hydrocarbons in coral tissues and the ambient sediments from Kenting National Park, Taiwan Texto completo
2014
Ko, Fung-Chi | Chang, Chiung-Wen | Cheng, Jing-O.
Surface sediments and corals (Acropora sp. and Montipora sp.) from the coastline of Kenting were analyzed in 2009 and 2010 for content levels of polycyclic aromatic hydrocarbons (PAHs) using gas chromatography-mass spectrometry. The total PAH concentrations (t-PAH) in corasls (143–1715 ng g−1 dw) were significantly higher than in the ambient sediments (2–59 ng g−1 dw) indicating the bioaccumulation of PAHs in corals. The spatial and seasonal variation in PAH levels suggested that land-loaded contaminants may be the main source of PAHs in the Kenting coral reefs. Based on molecular indices, PAHs were substantially of petroleum origin. The major PAH components were phenanthrene, pyrene and fluorine, but PAH congeners in corals and sediments still have characteristic composition patterns which would be altered by the bio/accumulation mechanisms. Further study is essential to assess and understand the impacts of these chemicals on coral reefs.
Mostrar más [+] Menos [-]Chemical and biological characterization of air particulate matter 2.5, collected from five cities in China Texto completo
2014
Leung, P.Y. | Wan, H.T. | Billah, M.B. | Cao, J.J. | Ho, K.F. | Wong, Chris K.C.
Fifteen polycyclic aromatic hydrocarbons (PAHs) in PM2.5 samples collected in five different cities (Hong Kong (HK), Guangzhou (GZ), Xiamen (XM), Xi'an (XA) and Beijing (BJ)) in China in the winter 2012–12 were analyzed by gas chromatography-mass spectrometry. The biological effects of organic extracts were assayed using the human bronchial epithelial cells BEAS-2B. All sixteen priority PAHs can be found in the PM2.5 samples of XA and BJ, but not in HK, GZ and XM, demonstrating the differential spatial source and distribution of PAHs. Our results showed that the total PAHs ranged from 3.35 to 80.45 ng/m3 air, leading by BJ, followed by XA, XM, GZ and HK. In the cell culture study, transcript levels of pro-inflammatory cytokine interleukin-6 (IL-6), CYP1A1 and CYP1B1 were found to be induced in the treatment. The cells exposed to extracts from XA and BJ demonstrated significant migratory activities, indicating a sign of increase of tumorigenicity.
Mostrar más [+] Menos [-]Are persistent organic pollutants and metals in eel muscle predictive for the ecological water quality? Texto completo
2014
Van Ael, Evy | Belpaire, Claude | Breine, Jan | Geeraerts, Caroline | Van Thuyne, Gerlinde | Eulaers, Igor | Blust, Ronny | Bervoets, Lieven
Relationships between the presence of PCBs, OCPs and metals in aquatic ecosystems and the ecological water quality were investigated by combining datasets of long-term monitoring of chemicals in European eel (Anguilla anguilla, N = 1156) in Flanders (Belgium) and the Ecological Quality Ratio (EQR), based on the assessment of fish assemblages at 185 locations. For most pollutants, EQR scores were lower when pollutant levels were higher. Threshold concentrations for a good quality could be formulated for PCB's, most metals and OCPs. Mixed models suggested that the ecological water quality was significantly correlated with the presence of PCBs. However, the low R2 indicates that other environmental pressures may significantly influence the biotic integrity of fish communities. Empirical data and their analyses are essential to enable defining threshold values of bioaccumulated levels to allow better protection of the aquatic environment and its biota through associated food webs as demanded by the Water Framework Directive.
Mostrar más [+] Menos [-]Pharmaceuticals occurrence in a WWTP with significant industrial contribution and its input into the river system Texto completo
2014
Collado, N. | Rodriguez-Mozaz, S. | Gros, M. | Rubirola, A. | Barceló, D. | Comas, J. | Rodriguez-Roda, I. | Buttiglieri, G.
Occurrence and removal of 81 representative Pharmaceutical Active Compounds (PhACs) were assessed in a municipal WWTP located in a highly industrialized area, with partial water reuse after UV tertiary treatment and discharge to a Mediterranean river. Water monitoring was performed in an integrated way at different points in the WWTP and river along three seasons.Consistent differences between therapeutic classes were observed in terms of influent concentration, removal efficiencies and seasonal variation. Conventional (primary and secondary) treatment was unable to completely remove numerous compounds and UV-based tertiary treatment played a complementary role for some of them. Industrial activity influence was highlighted in terms of PhACs presence and seasonal distribution.Even if global WWTP effluent impact on the studied river appeared to be minor, PhACs resulted widespread pollutants in river waters. Contamination can be particularly critical in summer in water scarcity areas, when water flow decreases considerably.
Mostrar más [+] Menos [-]Wet deposition of acidifying substances in different regions of China and the rest of East Asia: Modeling with updated NAQPMS Texto completo
2014
Ge, B.Z. | Wang, Z.F. | Xu, X.B. | Wu, J.B. | Yu, X.L. | Li, J.
The traditional way to study Sources–Receptor Relationships (SRRs) of wet deposition is based on sensitivity simulation, which has weakness in dealing with the non-linear secondary formation pollutants (e.g. ozone and nitrate). An on-line source tracking method has been developed in the Nested Air Quality Prediction Modeling System (NAQPMS) coupled with cloud-process module for the first time. The new model can not only quantify the total volume of the sulfate, nitrate and ammonium wet deposition with more accuracy, but also trace these acidic species to their emitted precursors. Compared with previous studies, our result clearly shows: (1) East China and Central China, which are the two primary export regions, have 15–30% and 10% effect on wet deposition in other areas, respectively; (2) Besides the above two regions, the total acid deposition in Southwestern and Northeastern China have reached or exceeded the critical loads under their own environmental conditions.
Mostrar más [+] Menos [-]Release of cadmium, copper and lead from urban soils of Copenhagen Texto completo
2014
Li, Lijun | Holm, Peter E. | Marcussen, Helle | Bruun Hansen, Hans Christian
We studied the bonding and release kinetics of Cd, Cu and Pb from different soils in the older metropolitan area of Copenhagen. Total Cd, Cu and Pb concentrations were elevated 5–27 times in the urban soils compared to an agricultural reference soil, with Cd and Pb in mainly mobilisable pools and Cu in strongly bound pools. The soils were subjected to accelerated leaching studies in Ca(NO3)2 or HNO3 solutions resulting in release up to 78, 18 and 15% of total Cd, Cu and Pb soil concentrations over a period of 15 weeks. The relative initial Cd and Pb release rates increased 10 fold when pH decreased 2 and 3 units, respectively, while increases in Cu release rates were only seen at pH below 4. The total leachable Cu and Pb pools were higher in urban soils compared the agricultural reference soil but not for Cd.
Mostrar más [+] Menos [-]Influential parameters on particle concentration and size distribution in the mainstream of e-cigarettes Texto completo
2014
Fuoco, F.C. | Buonanno, G. | Stabile, L. | Vigo, P.
Electronic cigarette-generated mainstream aerosols were characterized in terms of particle number concentrations and size distributions through a Condensation Particle Counter and a Fast Mobility Particle Sizer spectrometer, respectively. A thermodilution system was also used to properly sample and dilute the mainstream aerosol.Different types of electronic cigarettes, liquid flavors, liquid nicotine contents, as well as different puffing times were tested. Conventional tobacco cigarettes were also investigated.The total particle number concentration peak (for 2-s puff), averaged across the different electronic cigarette types and liquids, was measured equal to 4.39 ± 0.42 × 109 part. cm−3, then comparable to the conventional cigarette one (3.14 ± 0.61 × 109 part. cm−3). Puffing times and nicotine contents were found to influence the particle concentration, whereas no significant differences were recognized in terms of flavors and types of cigarettes used.Particle number distribution modes of the electronic cigarette-generated aerosol were in the 120–165 nm range, then similar to the conventional cigarette one.
Mostrar más [+] Menos [-]Incidence of anticancer drugs in an aquatic urban system: From hospital effluents through urban wastewater to natural environment Texto completo
2014
Ferrando-Climent, L. | Rodriguez-Mozaz, S. | Barceló, D.
The presence of 10 anticancer drugs was studied along the entire urban water cycle -from hospital effluents through urban wastewater treatment plant till surface waters- and their potential environmental risk was assessed. Azathioprine, etoposide, docetaxel, paclitaxel, methotrexate, cyclophosphamide, tamoxifen and ciprofloxacin were detected in hospital effluent and in the urban influent of the sewage treatment plant although most of them were totally eliminated after WWTP. Only cyclophosphamide, tamoxifen and ciprofloxacin were found in both WWTP effluent and in the receiving river at a concentration range between nd-20 ng L−1, 25–38 ng L−1 and 7–103 ng L−1 respectively. Tamoxifen and ciprofloxacin, commonly used for veterinary practices, were also detected in the river upstream the sewage discharge. In addition, they both were considered to pose a potential risk to the environment based on the levels found in the WWTP effluent together with their ecotoxicological impact in selected organisms.
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