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Characterization of polychlorinated dibenzo-p-dioxins and dibenzofurans, dioxin-like polychlorinated biphenyls, and polychlorinated naphthalenes in the environment surrounding secondary copper and aluminum metallurgical facilities in China 全文
2014
Hu, Jicheng | Zheng, Minghui | Liu, Wenbin | Nie, Zhiqiang | Li, Changliang | Liu, Guorui | Xiao, Ke
Unintentionally produced persistent organic pollutants (UP-POPs) were determined in ambient air from around five secondary non-ferrous metal processing plants in China, to investigate the potential impacts of the emissions of these plants on their surrounding environments. The target compounds were polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), dioxin-like polychlorinated biphenyls (dl-PCBs), and polychlorinated naphthalenes (PCNs). The PCDD/F, dl-PCB, and PCN concentrations in the ambient air downwind of the plants were 4.70–178, 8.23–7520 and 152–4190 pg/m3, respectively, and the concentrations upwind of the plants were lower. Clear correlations were found between ambient air and stack gas concentrations of the PCDD/Fs, dl-PCBs, and PCNs among the five plants, respectively. Furthermore, the UP-POPs homolog and congener patterns in the ambient air were similar to the patterns in the stack gas samples. These results indicate that UP-POPs emissions from the plants investigated have obvious impacts on the environments surrounding the plants.
显示更多 [+] 显示较少 [-]Comparing i-Tree modeled ozone deposition with field measurements in a periurban Mediterranean forest 全文
2014
Morani, A. | Nowak, D. | Hirabayashi, S. | Guidolotti, G. | Medori, M. | Muzzini, V. | Fares, S. | Mugnozza, G Scarascia | Calfapietra, C.
Ozone flux estimates from the i-Tree model were compared with ozone flux measurements using the Eddy Covariance technique in a periurban Mediterranean forest near Rome (Castelporziano). For the first time i-Tree model outputs were compared with field measurements in relation to dry deposition estimates. Results showed generally a good agreement between predicted and measured ozone fluxes (least sum square = 5.6 e−4) especially when cumulative values over the whole measurement campaign are considered. However at daily and hourly time-step some overestimations were observed in estimated values especially in hot dry periods. The use of different m values in the Ball–Berry formula in the different periods, produced the best fit between predicted and measured ozone fluxes. This suggests that a variable value for the coefficient m accounting for water availability may be appropriate to improve model estimates for Mediterranean and drought prone regions.
显示更多 [+] 显示较少 [-]Ozone levels in European and USA cities are increasing more than at rural sites, while peak values are decreasing 全文
2014
Paoletti, Elena | De Marco, Alessandra | Beddows, David C.S. | Harrison, Roy M. | Manning, William J.
Ground-level ozone (O3) levels are usually lower in urban centers than nearby rural sites. To compare trends in O3 levels during the period 1990–2010, we obtained monitoring data from paired urban and rural sites from the European Environment Agency and the US Environmental Protection Agency. Ozone peaks decreased at both station types, with no significant differences between urban and rural stations. Ozone annual averages increased at both urban and rural sites, with a faster rate of increase for urban centers. The overall trend was for convergence between urban and rural O3 data. Ozone levels exceeded the criteria established for the protection of human and vegetation health at both urban and rural sites.
显示更多 [+] 显示较少 [-]Associations of accumulated exposure to persistent organic pollutants with serum lipids and obesity in an adult cohort from Southern Spain 全文
2014
Arrebola, Juan P. | Ocaña-Riola, Ricardo | Arrebola-Moreno, Antonio L. | Fernández-Rodríguez, María | Martin-Olmedo, Piedad | Fernández, Mariana F. | Olea, Nicolás
The aim of this research was to study the association of the accumulated human exposure to persistent organic pollutants with serum lipid levels and obesity, in a cohort of 298 adults.In the multivariable analyses, HCB concentrations evidenced a significant quadratic association with levels of total cholesterol, HDL, LDL, and total serum lipids. Likewise, PCBs 138 and 180 were associated with triglycerides and total serum lipids, and PCB 153 with LDL. HCB, p,p′-DDE, and β-HCH showed quadratic associations with BMI. All quadratic models showed a positive trend at low exposure levels, while the slope decreased or even became negative at higher exposure levels. Additionally, PCB 138 was positively associated with BMI but in a linear manner. Our results suggest a potential relationship between historical POP exposure and serum lipids/obesity, which followed a non-linear pattern in most cases.
显示更多 [+] 显示较少 [-]Explaining PAH desorption from sediments using Rock Eval analysis 全文
2014
Poot, Anton | Jonker, M.T.O. | Gillissen, Frits | Koelmans, Albert A.
Here, we provide Rock Eval and black carbon (BC) characteristics and polycyclic aromatic hydrocarbon (PAH) distribution coefficients (KD) for sediments from the Danube, Elbe, Ebro, and Meuse river basins. PAH desorption kinetic parameters were determined using sequential Tenax extractions. We show that residual carbon (RC) from Rock Eval analysis is an adequate predictor of fast, slow, and very slow desorbing fractions of 4-ring PAHs. RC correlated better than BC, the latter constituting only 7% of RC. A dual domain sorption model was statistically superior to a single domain model in explaining KD for low molecular weight PAHs, whereas the opposite was observed for high molecular weight PAHs. Because particularly the 4-ring PAHs are bioavailable and relevant from a risk assessment perspective and because their fast desorbing fractions correlate best with RC, we recommend RC as a relevant characteristic for river sediments.
显示更多 [+] 显示较少 [-]Prevalence and sunlight photolysis of controlled and chemotherapeutic drugs in aqueous environments 全文
2014
Lin, Angela Yu-Chen | Lin, Yanjing | Lee, Wan-Ning
This study addresses the occurrences and natural fates of chemotherapeutics and controlled drugs when found together in hospital effluents and surface waters. The results revealed the presence of 11 out of 16 drugs in hospital effluents, and the maximum detected concentrations were at the μg L−1 level in the hospital effluents and the ng L−1 level in surface waters. The highest concentrations corresponded to meperidine, morphine, 5-fluorouracil and cyclophosphamide. The sunlight photolysis of the target compounds was investigated, and the results indicated that morphine and codeine can be significantly attenuated, with half-lives of 0.27 and 2.5 h, respectively, in natural waters. Photolysis can lower the detected environmental concentrations, also lowering the estimated environmental risks of the target drugs to human health. Nevertheless, 5-fluorouracil and codeine were found to have a high risk quotient (RQ), demonstrating the high risks of directly releasing hospital wastewater into the environment.
显示更多 [+] 显示较少 [-]Regional distribution of styrene analogues generated from polystyrene degradation along the coastlines of the North-East Pacific Ocean and Hawaii 全文
2014
Kwon, Bum Gun | Saido, Katsuhiko | Koizumi, Koshiro | Sato, Hideto | Ogawa, Naoto | Chung, Seon -Yong | Kusui, Takashi | Kodera, Yoichi | Kogure, Kazuhio
Beach sand and seawater taken from the coastlines of the North-East Pacific Ocean and Hawaii State were investigated to determine the causes of global chemical contamination from polystyrene (PS). All samples were found to contain styrene monomer (SM), styrene dimers (SD), and styrene trimers (ST) with a concentration distribution of styrene analogues in the order of ST > SD > SM. The contamination by styrene analogues along the West Coast proved more severe than in Alaska and other regions. The Western Coastlines of the USA seem be affected by both land- and ocean-based pollution sources, which might result from it being a heavily populated area as the data suggest a possible proportional relationship between PS pollution and population. Our results suggest the presence of new global chemical contaminants derived from PS in the ocean, and along coasts.
显示更多 [+] 显示较少 [-]Wetlands as long-term sources of metals to receiving waters in mining-impacted landscapes 全文
2014
Szkokan-Emilson, E.J. | Watmough, S.A. | Gunn, J.M.
Wetlands are prevalent in the Sudbury, Ontario region and often operate at the interface between terrestrial and aquatic ecosystems, modifying water chemistry and potentially affecting the recovery of impacted lakes. The deposition of metals and sulphur in Sudbury in 2010–2012 was far below that reported in the 1970's, but still higher than background values. Wetlands in the area have accumulated large quantities of metals, and high concentrations of these metals in streams occurred primarily in response to SO4-related acidification events or associated with high dissolved organic carbon production in early summer. Concentrations of most metals in streams exceeded provincial guidelines and fluxes of some metals from catchments exceeded deposition inputs to lakes by as much as 12 times. The release of metals long after emissions reductions have been achieved must be considered in ecosystem recovery studies, particularly as dry conditions may become more prevalent in boreal regions affected by mining.
显示更多 [+] 显示较少 [-]Influence of plants on the distribution and composition of PBDEs in soils of an e-waste dismantling area: Evidence of the effect of the rhizosphere and selective bioaccumulation 全文
2014
Rhizosphere effects on the distribution of PBDEs in e-waste contaminated soils were investigated. The geometric means of the PBDEs in the rhizosphere and non-rhizosphere soils were 32.6 ng/g and 12.2 ng/g, whereas the geometric means of the PBDEs in vegetable shoots and roots were 2.15 ng/g and 3.02 ng/g, respectively. PBDEs in soil at different distances from the root surface may first rise appreciably and then decrease to a non-rhizosphere level for long-term contaminated soils. Different PBDE compositions in roots and shoots indicated that PBDEs in shoots may be mainly taken up from the air. The ratios of BDE99/100 and BDE153/154 in plants and their corresponding soils were different. The bioaccumulations of BDEs 100 and 154 were much higher than those of BDEs 99 and 153, respectively. This indicated that the bioaccumulation was selective and influenced by the substitution pattern, with ortho-substituted isomers being more prevalent than meta-substituted isomers.
显示更多 [+] 显示较少 [-]Do predictions from Species Sensitivity Distributions match with field data? 全文
2014
Smetanová, S. | Bláha, L. | Liess, M. | Schäfer, R.B. | Beketov, M.A.
Species Sensitivity Distribution (SSD) is a statistical model that can be used to predict effects of contaminants on biological communities, but only few comparisons of this model with field studies have been conducted so far. In the present study we used measured pesticides concentrations from streams in Germany, France, and Finland, and we used SSD to calculate msPAF (multiple substance potentially affected fraction) values based on maximum toxic stress at localities. We compared these SSD-based predictions with the actual effects on stream invertebrates quantified by the SPEARpesticides bioindicator. The results show that the msPAFs correlated well with the bioindicator, however, the generally accepted SSD threshold msPAF of 0.05 (5% of species are predicted to be affected) severely underestimated the observed effects (msPAF values causing significant effects are 2–1000-times lower). These results demonstrate that validation with field data is required to define the appropriate thresholds for SSD predictions.
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