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The Danube so colourful: A potpourri of plastic litter outnumbers fish larvae in Europe's second largest river Texto completo
2014
Lechner, Aaron | Keckeis, Hubert | Lumesberger-Loisl, Franz | Zens, Bernhard | Krusch, Reinhard | Tritthart, Michael | Glas, Martin | Schludermann, Elisabeth
Previous studies on plastic pollution of aquatic ecosystems focused on the world's oceans. Large rivers as major pathways for land-based plastic litter, has received less attention so far. Here we report on plastic quantities in the Austrian Danube. A two year survey (2010, 2012) using stationary driftnets detected mean plastic abundance (n = 17,349; mean ± S.D: 316.8 ± 4664.6 items per 1000 m−3) and mass (4.8 ± 24.2 g per 1000 m−3) in the river to be higher than those of drifting larval fish (n = 24,049; 275.3 ± 745.0 individuals. 1000 m−3 and 3.2 ± 8.6 g 1000 m−3). Industrial raw material (pellets, flakes and spherules) accounted for substantial parts (79.4%) of the plastic debris. The plastic input via the Danube into the Black Sea was estimated to 4.2 t per day.
Mostrar más [+] Menos [-]Exposure to air pollutants and mortality in hypertensive patients according to demography: A 10 year case-crossover study Texto completo
2014
Wong, Martin C.S. | Tam, Wilson W.S. | Wang, Harry H.X. | Lao, X.Q. | Zhang, Daisy Dexing | Chan, Sky W.M. | Kwan, Mandy W.M. | Fan, Carmen K.M. | Cheung, Clement S.K. | Tong, Ellen L.H. | Cheung, N.T. | Tse, L.A. | Yu, Ignatius T.S.
This study evaluated whether short term exposures to NO2, O3, particulate matter <10 mm in diameter (PM10) were associated with higher risk of mortality. A total of 223,287 hypertensive patients attended public health-care services and newly prescribed at least 1 antihypertensive agent were followed-up for up to 5 years. A time-stratified, bi-directional case-crossover design was adopted. For all-cause mortality, significant positive associations were observed for NO2 and PM10 at lag 0–3 days per 10 μg/m3 increase in concentration (excess risks 1.187%–2.501%). Significant positive associations were found for O3 at lag 1 and 2 days and the excess risks were 1.654% and 1.207%, respectively. We found similarly positive associations between these pollutants and respiratory disease mortality. These results were significant among those aged ≥65 years and in cold seasons only. Older hypertensive patients are susceptible to all-cause and respiratory disease-specific deaths from these air pollutants in cold weather.
Mostrar más [+] Menos [-]Ingestion and transfer of microplastics in the planktonic food web Texto completo
2014
Setälä, Outi | Fleming-Lehtinen, Vivi | Lehtiniemi, Maiju
Experiments were carried out with different Baltic Sea zooplankton taxa to scan their potential to ingest plastics. Mysid shrimps, copepods, cladocerans, rotifers, polychaete larvae and ciliates were exposed to 10 μm fluorescent polystyrene microspheres. These experiments showed ingestion of microspheres in all taxa studied. The highest percentage of individuals with ingested spheres was found in pelagic polychaete larvae, Marenzelleria spp. Experiments with the copepod Eurytemora affinis and the mysid shrimp Neomysis integer showed egestion of microspheres within 12 h. Food web transfer experiments were done by offering zooplankton labelled with ingested microspheres to mysid shrimps. Microscopy observations of mysid intestine showed the presence of zooplankton prey and microspheres after 3 h incubation. This study shows for the first time the potential of plastic microparticle transfer via planktonic organisms from one trophic level (mesozooplankton) to a higher level (macrozooplankton). The impacts of plastic transfer and possible accumulation in the food web need further investigations.
Mostrar más [+] Menos [-]Occurrence and profiles of bisphenol analogues in municipal sewage sludge in China Texto completo
2014
Song, Shanjun | Song, Maoyong | Zeng, Luzhe | Wang, Thanh | Liu, Runzeng | Ruan, Ting | Jiang, Guibin
Extensive use of bisphenol A and its analogues has caused increasing concern over the potential adverse health impacts of these chemicals. In this study, the presence and profiles of 13 bisphenols (BPs) were investigated in 52 municipal sewage sludge samples collected from 30 cities in China. Tetrabromobisphenol A was the most frequently observed analogue (geometric mean: 20.5 ng/g dw). Bisphenol A (4.69 ng/g dw), bisphenol S (3.02 ng/g dw), and bisphenol F (3.84 ng/g dw) were found with similar frequency. Other BP analogues such as tetrachlorobisphenol A, bisphenol AF, bisphenol E, and dihydroxybiphenyl were identified for the first time in sewage sludge in China. Significant correlations were found among BP concentrations, but no relationships were found with wastewater treatment plant characteristics. Profiles of the relative estradiol equivalents suggested that the estrogenic potential of BP mixtures may be associated with the occurrence and contributions of specific analogues.
Mostrar más [+] Menos [-]Polycyclic aromatic hydrocarbons in surface soil across the Tibetan Plateau: Spatial distribution, source and air–soil exchange Texto completo
2014
Wang, Chuanfei | Wang, Xiaoping | Gong, Ping | Yao, Tandong
There are limited data on polycyclic aromatic hydrocarbons (PAHs) in both the atmosphere and soil of the Tibetan Plateau (TP). Concentrations of PAHs were therefore measured in 13 XAD resin-based passive air samplers and 41 surface (0–5 cm) soil samples across the TP. The average concentration of atmospheric PAHs was 5.55 ng/m3, which was lower than that reported for other background areas, but higher than the Arctic. Concentrations in the soils fell in a wide range from 5.54 to 389 ng/g, with an average of 59.9 ng/g. Elevation was found to play an important role in determining the spatial distribution of soil PAHs. The air–soil exchange state showed that the soils of the TP will likely remain as a sink for high molecular weight PAHs, but may become a potential “secondary source” for low molecular weight PAHs.
Mostrar más [+] Menos [-]Quantitative assessments of indoor air pollution and the risk of childhood acute leukemia in Shanghai Texto completo
2014
Gao, Yu | Zhang, Yan | Kamijima, Michihiro | Sakai, Kiyoshi | Khalequzzaman, Md. | Nakajima, Tamie | Shi, Rong | Wang, Xiaojin | Chen, Didi | Ji, Xiaofan | Han, Kaiyi | Tian, Ying
We investigated the association between indoor air pollutants and childhood acute leukemia (AL). A total of 105 newly diagnosed cases and 105 1:1 gender-, age-, and hospital-matched controls were included. Measurements of indoor pollutants (including nitrogen dioxide (NO2) and 17 types of volatile organic compounds (VOCs)) were taken with diffusive samplers for 64 pairs of cases and controls. Higher concentrations of NO2 and almost half of VOCs were observed in the cases than in the controls and were associated with the increased risk of childhood AL. The use of synthetic materials for wall decoration and furniture in bedroom was related to the risk of childhood AL. Renovating the house in the last 5 years, changing furniture in the last 5 years, closing the doors and windows overnight in the winter and/or summer, paternal smoking history and outdoor pollutants affected VOC concentrations. Our results support the association between childhood AL and indoor air pollution.
Mostrar más [+] Menos [-]Characterization of estrogen receptor α activities in polychlorinated biphenyls by in vitro dual-luciferase reporter gene assay Texto completo
2014
Zhang, Quan | Lu, Meiya | Wang, Cui | Du, Jie | Zhou, Peixue | Zhao, Meirong
Polychlorinated biphenyls (PCBs) are thought to cause adverse health effects, particularly endocrine disruption. However, results on the estrogenic activities of a large set of PCB congeners through hormone receptors have not been fully studied. In this study, we evaluated the anti/estrogenic effects of 20 PCBs using an in vitro dual-luciferase reporter gene assay. PCB 18, 28, 49, 52, 99, 101, 103, 110, and 128 exhibited estrogenic effects, whereas PCB 118, 138, 163, 170, 180, 187, 194, 199 and 203 behaved as anti-estrogens. In particular, PCB 30 and 44 exhibited both agonistic and antagonistic activities in the dual-luciferase reporter gene assay. The results obtained from the dual-luciferase reporter gene assay, yeast two-hybrid assay and E-SCREEN were compared, suggesting that the dual-luciferase reporter gene assay is a useful approach for high-throughput screening. We also predicted the possible relationship between the chemical structures and the estrogenic effects of PCBs.
Mostrar más [+] Menos [-]Particle-bound PAHs quantification using a 3-stages cascade impactor in French indoor environments Texto completo
2014
Liaud, Céline | Dintzer, Thierry | Tschamber, Valérie | Trouve, Gwénaëlle | Le Calvé, Stéphane
Cascade Impactor is a powerful sampling method to collect airborne particles as a function of their size. The 3-stages Cascade Impactor used in this study allowed to sample simultaneously particles with aerodynamic diameter Dae > 10 μm, 2.5 μm < Dae < 10 μm, 1 μm < Dae < 2.5 μm and Dae < 1 μm. Once collected individual concentrations of the 16 US-EPA priority Polycyclic Aromatic Hydrocarbons (PAHs) bound to particles were quantified for 8 different indoor environments located in Strasbourg area in France. All the heavy PAHs owning between 4 and 6 aromatic rings were detected in all of the 8 sampling sites. The total PAHs concentration varied from 0.44 to 2.09 ng m−3 for a low-energy building school and a smoking apartment, respectively. Results revealed also that high molecular weight PAHs were mainly associated to the finest particles. Our data are consistent with those measured elsewhere in European indoor environments.
Mostrar más [+] Menos [-]The effect of dibenzo-p-dioxin- and dibenzofuran-contaminated soil on the earthworm Eisenia andrei Texto completo
2014
Roubalová, Radka | Dvořák, Jiří | Procházková, Petra | Elhottová, Dana | Rossmann, Pavel | Škanta, František | Bilej, M.
Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) belong to the group of persistent organic pollutants, highly toxic environmental pollutants that include hydrophobic compounds with the tendency to bioaccumulate. Earthworms (Eisenia andrei) were exposed to PCDD/Fs-contaminated soil, and changes in their lipophilic structures and the gene expression of their defense molecules were followed. Damage to the intestinal wall and adjacent chloragogenous tissue was observed. Further, the up-regulation of the expression of several genes was detected. On the basis of these results, the mechanism of the impact of PCDD/Fs on earthworms has been proposed. Dioxins that accumulate in the lipophilic structures cause an increase in reactive oxidative species that triggers oxidative stress followed by the gene expression of two molecules that play a role in protection against oxidant toxicity, calreticulin (CRT) and Hsp70. Moreover, the effect of microbial biomass on the expression of coelomic cytolytic factor (CCF), a pattern recognition receptor, was also observed.
Mostrar más [+] Menos [-]Modeling of black carbon in Asia using a global-to-regional seamless aerosol-transport model Texto completo
2014
Gotō, Daisuke
In Asia, the evaluation of black carbon (BC) using global aerosol-transport models has been incomplete due to a lack of available measurements. Recently, new measurements and datasets at various Asian sites have become available for use in model validation. In this study, we compared the BC mass concentrations obtained by an aerosol-coupled global nonhydrostatic model adopting a uniform-grid system with in-situ measurements and other models over Asia. The results revealed that our model, as well as other global models, was unable to reproduce the observed BC values at most sites in China and India, most likely due to strong local hotspots. To overcome the inconsistency between the models and measurements, we developed a new aerosol-transport model using a stretched-grid system for high-resolution simulations with up to approximately 10 km grids. Our model can be used as a global-to-regional seamless aerosol-transport model for low to high horizontal resolution simulations.
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