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Acute effects of air pollution on asthma hospitalization in Shanghai, China Texto completo
2014
Cai, Jing | Zhao, Ang | Zhao, Jinzhuo | Chen, Renjie | Wang, Weibing | Ha, Sandie | Xu, Xiaohui | Kan, Haidong
Air pollution has been accepted as an important contributor to asthma development and exacerbation. However, the evidence is limited in China. In this study, we investigated the acute effect of air pollution on asthma hospitalization in Shanghai, China. We applied over-dispersed generalized additive model adjusted for weather conditions, day of the week, long-term and seasonal trends. An interquartile range increase in the moving average concentrations of PM10, SO2, NO2 and BC on the concurrent day and previous day corresponded to 1.82%, 6.41%, 8.26% and 6.62% increase of asthmatic hospitalization, respectively. The effects of SO2 and NO2 were robust after adjustment for PM10. The associations appeared to be more evident in the cool season than in the warm season. Our results contribute to the limited data in the scientific literature on acute effects of air pollution on asthma in high exposure settings, which are typical in developing countries.
Mostrar más [+] Menos [-]Effects of the geophagous earthworm Metaphire guillelmi on sorption, mineralization, and bound-residue formation of 4-nonylphenol in an agricultural soil Texto completo
2014
Shan, Jun | Wang, Yongfeng | Wang, Lianhong | Yan, Xiaoyuan | Ji, Rong
Effects of earthworms on fate of nonylphenol (NP) are obscure. Using 14C-4-NP111 as a representative, we studied the fate of 4-NP in an agricultural soil with or without the earthworm Metaphire guillelmi and in fresh cast of the earthworm. Sorption of 4-NP on the cast (Kd 1564) was significantly higher than on the parent soil (Kd 1474). Mineralization of 4-NP was significantly lower in the cast (13.2%) and the soil with earthworms (10.4%) than in the earthworm-free soil (16.0%). One nitro metabolite of 4-NP111 (2-nitro-4-NP111) was identified in the soil and cast, and the presence of the earthworm significantly decreased its amounts. The presence of earthworm also significantly decreased formation of bound residues of 4-NP in the soil. Our results demonstrate that earthworms could significantly change the fate of 4-NP, underlining that earthworm effects should be considered when evaluating behavior and risk of 4-NP in soil.
Mostrar más [+] Menos [-]A new analytical approach for monitoring microplastics in marine sediments Texto completo
2014
Nuelle, Marie-Theres | Dekiff, Jens H. | Rémy, Dominique | Fries, Elke
A two-step method was developed to extract microplastics from sediments. First, 1 kg sediments was pre-extracted using the air-induced overflow (AIO) method, based on fluidisation in a sodium chloride (NaCl) solution. The original sediment mass was reduced by up to 80%. As a consequence, it was possible to reduce the volume of sodium iodide (NaI) solution used for the subsequent flotation step. Recoveries of the whole procedure for polyethylene, polypropylene (PP), polyvinyl chloride (PVC), polyethylene terephthalate (PET), polystyrene and polyurethane with sizes of approximately 1 mm were between 91 and 99%. After being stored for one week in a 35% H2O2 solution, 92% of selected biogenic material had dissolved completely or had lost its colour, whereas the tested polymers were resistant. Microplastics were extracted from three sediment samples collected from the North Sea island Norderney. Using pyrolysis gas chromatography/mass spectrometry, these microplastics were identified as PP, PVC and PET.
Mostrar más [+] Menos [-]Adsorption of polar, nonpolar, and substituted aromatics to colloidal graphene oxide nanoparticles Texto completo
2014
Wang, Fang | Haftka, Joris J.-H. | Sinnige, Theo L. | Hermens, Joop L.M. | Chen, Wei
We conducted batch adsorption experiments to understand the adsorptive properties of colloidal graphene oxide nanoparticles (GONPs) for a range of environmentally relevant aromatics and substituted aromatics, including model nonpolar compounds (pyrene, phenanthrene, naphthalene, and 1,3-dichlorobenzene) and model polar compounds (1-naphthol, 1-naphthylamine, 2,4-dichlorophenol, and 2,4-dinitrotoluene). GONPs exhibited strong adsorption affinities for all the test compounds, with distribution coefficients on the order of 103–106 L/kg. Adsorption to GONPs is much more linear than to carbon nanotubes (CNTs) and C60, likely because GO nanoflakes are essentially individually dispersed (rendering adsorption sites of similar adsorption energy) whereas CNT/C60 are prone to bundling/aggregation. For a given compound GONPs and CNTs often exhibit different adsorption affinities, which is attributable to the differences in both the morphology and surface chemistry between the two nanomaterials. Particularly, the high surface O-content of GONPs enables strong H-bonding and Lewis acid–base interactions with hydroxyl- and amino-substituted aromatics.
Mostrar más [+] Menos [-]If you could turn back time: Understanding transgenerational latent effects of developmental exposure to contaminants Texto completo
2014
Kimberly, David A. | Salice, Christopher J.
Latent effects result from embryonic experiences but manifest in later stages of ontogeny. Our objective was to better understand how developmental exposure to contaminants influence life history traits and tolerance to novel stress in the freshwater gastropod, Physa pomilia. Ten egg masses were exposed to each of three initial treatments including control, 2.5 μg/L cadmium (Cd), and 10 μg/L Cd; there was no effect of this initial treatment on hatching success. At hatching, snails were transferred to cadmium-free water. Three weeks later, snails were divided among four secondary treatments including control, 50 μg/L Cd, 150 μg/L Cd, and 35 °C. Developmental Cd exposure plus secondary temperature stress caused the most adverse effects. Surprisingly, developmental Cd exposure alone was enough to cause significant decreases in reproductive success a generation later. That effects can manifest as transgenerational decrements in reproductive success suggests that latent effects are important and have longer lasting consequences than previously considered.
Mostrar más [+] Menos [-]Lead contamination and transfer in urban environmental compartments analyzed by lead levels and isotopic compositions Texto completo
2014
Hu, Xin | Sun, Yuanyuan | Ding, Zhuhong | Zhang, Yun | Wu, Jichun | Lian, Hongzhen | Wang, Tijian
Lead levels and isotopic compositions in atmospheric particles (TSP and PM2.5), street dust and surface soil collected from Nanjing, a mega city in China, were analyzed to investigate the contamination and the transfer of lead in urban environmental compartments. The lead contents in TSP and PM2.5 are significantly higher than them in the surface soil and street dust (p < 0.05). The enrichment factor using the mass ratio of lead to the major crustal elements (Al, Sr, Ti and Fe) indicates significant lead enrichment in atmospheric particles. The plots of 206Pb/207Pb vs.208Pb/206Pb and 206Pb/207Pb vs. 1/Pb imply that the street dust and atmospheric particles (TSP and PM2.5) have very similar lead sources. Coal emissions and smelting activities may be the important lead sources for street dust and atmospheric particles (TSP and PM2.5), while the deposition of airborne lead is an important lead source for urban surface soil.
Mostrar más [+] Menos [-]Species composition of a soil invertebrate multi-species test system determines the level of ecotoxicity Texto completo
2014
Sechi, Valentina | D'Annibale, Alessandra | Maraldo, Kristine | Johansen, Anders | Bossi, Rossana | Jensen, John | Krogh, Paul Henning
A soil multi-species, SMS, experimental test system consisting of the natural microbial community, five collembolan species and a predatory mite along with either Enchytraeus crypticus or the earthworm Eisenia fetida were exposed to α-cypermethrin. A comparison of the performance of these two types of SMSs is given to aid the development of a standard test system. E. fetida had a positive effect on the majority of the species, reducing the negative insecticide effect. E. fetida affected the species sensitivity and decreased the degradation of the insecticide due to the organic matter incorporation of earthworm food. After 8 weeks, the EC50 was 0.76 mg kg−1 for enchytraeids and ranged between 2.7 and 18.9 mg kg−1 for collembolans, more sensitive than previously observed with single species. Changes observed in the community structure and function illustrates the strength of a multi-species test system as an ecotoxicological tool compared to single species tests.
Mostrar más [+] Menos [-]Biodegradability of pharmaceutical compounds in agricultural soils irrigated with treated wastewater Texto completo
2014
Grossberger, Amnon | Hadar, Y. (Yitzhak) | Borch, Thomas | Chefetz, Benny
Pharmaceutical compounds (PCs) are introduced into agricultural soils via irrigation with treated wastewater (TWW). Our data show that carbamazepine, lamotrigine, caffeine, metoprolol, sulfamethoxazole and sildenafil are persistent in soils when introduced via TWW. However, other PCs, namely diclofenac, ibuprofen, bezafibrate, gemfibrozil and naproxen were not detected in soils when introduced via TWW. This is likely due to rapid degradation as confirmed in our microcosm studies where they exhibited half-lives (t1/2) between 0.2–9.5 days when soils were spiked at 50 ng/g soil and between 3 and 68 days when soils were spiked at 5000 ng/g soil. The degradation rate and extent of PCs observed in microcosm studies were similar in soils that had been previously irrigated with TWW or fresh water. This suggests that pre-exposure of the soils to PCs via irrigation with TWW does not enhance their biodegradation. This suggests that PCs are probably degraded in soils via co-metabolism.
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 [-]Spatial and temporal trends in brominated flame retardants in seabirds from the Pacific coast of Canada Texto completo
2014
Miller, Aroha | Elliott, John E. | Elliott, Kyle H. | Guigueno, Mélanie F. | Wilson, Laurie K. | Lee, Sandi | Idrissi, Abde
Polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCDD) are bioaccumulative flame retardants. PBDEs increased in many ecosystems during the late 20th century, but recently have declined in some environments. To examine trends in the northern Pacific, we analysed PBDEs, HBCDD and carbon and nitrogen stable isotopes (δ13C and δ15N) to account for dietary effects in archived eggs of three seabird species from British Columbia, Canada, 1990–2011 (rhinoceros auklets, Cerorhinca monocerata; Leach's storm-petrels, Oceanodroma leucorhoa; ancient murrelets, Synthliboramphus antiquus, 2009 only). PBDEs increased until approximately 2000 and then decreased, while HBCDD increased exponentially throughout the examined period. No significant changes in dietary tracers were observed. HBCDD and ΣPBDE levels varied among species; ΣPBDE also varied among sites. Temporal changes in contaminant concentrations are unlikely to have been caused by dietary changes, and likely reflect the build-up followed by decreases associated with voluntary phase-outs and regulations implemented in North America to control PBDEs.
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