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Результаты 481-490 из 4,309
Ambient temperature and emergency department visits: Time-series analysis in 12 Chinese cities Полный текст
2017
Zhao, Qi | Zhang, Yongming | Zhang, Wenyi | Li, Shanshan | Chen, Gongbo | Wu, Yanbin | Qiu, Chen | Ying, Kejing | Tang, Huaping | Huang, Jian-an | Williams, Gail | Huxley, Rachel | Guo, Yuming
The association between ambient temperature and mortality has been well documented worldwide. However, limited data are available on nonfatal health outcomes, such as emergency department visits (EDVs), particularly from China.To examine the temperature-EDV association in 12 Chinese cities; and to assess the modification effects by region, gender and age.Daily meteorological data and non-accidental EDVs were collected during 2011–2014. Poisson regression with distributed lag non-linear model was applied to examine the temperature-lag-EDV association in each city. The effect estimates were pooled using multivariate meta-analysis at the national and regional level. Stratified analyses were performed by gender and age-groups. Sensitivity analyses adjusting for air pollution and relative humidity were conducted.A total of 4,443,127 EDVs were collected from the 12 cities. Both cold and hot temperatures were associated with increased risk of EDVs, with minimum-mortality temperature located at 64th percentile of temperature. The effect of cold temperature appeared on day 2 and persisted until day 30, causing a cumulative relative risk (RR) of 1.80 (1.54, 2.11). The effect of hot temperature appeared immediately and lasted until day 3, with a cumulative RR of 1.15 (1.03, 1.29). The effect of temperature on EDVs was similar in male and female but was attenuated with increasing age. The effect of cold temperature on EDVs was greater in southern areas of the country whereas the hot effect was greater in northern cities. The association was robust to a large range of sensitivity analyses.In China, there is a U-shaped association between temperature and risk of EDVs that is independent of air pollution and humidity. The temperature-EDV association varies with latitude and age-groups but is not affected by gender. Forecasting models for hospital emergency departments may be improved if temperature is included as an independent predictor.
Показать больше [+] Меньше [-]Assessing the potential of inorganic anions (Cl−, NO3−, SO42− and PO43−) to increase the bioaccessibility of emitted palladium in the environment: Experimental studies with soils and a Pd model substance Полный текст
2017
Zereini, Fathi | Wiseman, Clare L.S. | Poprizki, Jana | Albers, Peter | Schneider, Wolfgang | Leopold, Kerstin
Palladium (Pd) emitted from vehicles equipped with exhaust catalytic converters has been accumulating at a greater rate relative to other platinum group elements (PGE) in the last 10–20 years. Little is known, however, regarding the various environmental factors and conditions which are likely to modulate the chemical behavior and bioaccessibility of this element post-emission. To meet data needs, soils and a Pd model substance were treated with solutions containing common anions (Cl−, NO3−, SO42− und PO43−) to shed light on the geochemical behavior of emitted Pd under ambient conditions. As part of this, the particle surface chemistry of treated residues (insoluble phase) and solutions (soluble phase) was examined using XPS to assess the chemical transformation of Pd in the presence of inorganic anions. The results show that Pd is the most soluble in the presence of anionic species, followed by rhodium (Rh) and platinum (Pt). Pd in field-collected samples was found to be considerably more soluble than the metallic Pd in the model substance, Pd black, when treated with anionic species. The results also demonstrate that the solubility of Pd black is strongly dependent on solution pH, concentration and the duration of reaction. The outer 3–4 atomic layers of metallic Pd was determined via XPS to be partially oxidized when treated with anion solutions, with the degree being dependent on anion type. The concentration of dissolved O2 in solution was found to have little impact on the transformation of metallic Pd. Given the ubiquitous nature of the anions examined, we can expect that Pd will become more bioaccessible post-emission.
Показать больше [+] Меньше [-]Metabolic disruption of zebrafish (Danio rerio) embryos by bisphenol A. An integrated metabolomic and transcriptomic approach Полный текст
2017
Ortiz-Villanueva, Elena | Navarro-Martín, Laia | Jaumot, Joaquim | Benavente, Fernando | Sanz-Nebot, Victoria | Piña, Benjamín | Tauler, Romà
Metabolic disruption of zebrafish (Danio rerio) embryos by bisphenol A. An integrated metabolomic and transcriptomic approach Полный текст
2017
Ortiz-Villanueva, Elena | Navarro-Martín, Laia | Jaumot, Joaquim | Benavente, Fernando | Sanz-Nebot, Victoria | Piña, Benjamín | Tauler, Romà
Although bisphenol A (BPA) is commonly recognized as an endocrine disruptor, the metabolic consequences of its exposure are still poorly understood. In this study, we present a non-targeted LC-MS based metabolomic analysis in combination with a full-genome, high-throughput RNA sequencing (RNA-Seq) to reveal the metabolic effects and the subjacent regulatory pathways of exposing zebrafish embryos to BPA during the first 120 hours post-fertilization. We applied multivariate data analysis methods to extract biochemical information from the LC-MS and RNA-Seq complex datasets and to perform testable predictions of the phenotypic adverse effects. Metabolomic and transcriptomic data revealed a similar subset of altered pathways, despite the large difference in the number of identified biomarkers (around 50 metabolites and more than 1000 genes). These results suggest that even a moderate coverage of zebrafish metabolome may be representative of the global metabolic changes. These multi-omic responses indicate a specific metabolic disruption by BPA affecting different signaling pathways, such as retinoid and prostaglandin metabolism. The combination of transcriptomic and metabolomic data allowed a dynamic interpretation of the results that could not be drawn from either single dataset. These results illustrate the utility of -omic integrative analyses for characterizing the physiological effects of toxicants beyond the mere indication of the affected pathways.
Показать больше [+] Меньше [-]Metabolic disruption of zebrafish (Danio rerio) embryos by bisphenol A. An integrated metabolomic and transcriptomic approach Полный текст
2017
Ortiz-Villanueva, Elena | Navarro-Martín, Laia | Jaumot, Joaquim | Benavente, Fernando | Sanz-Nebot, Victoria M. | Piña, Benjamín | Tauler, Romà | European Commission
Although bisphenol A (BPA) is commonly recognized as an endocrine disruptor, the metabolic consequences of its exposure are still poorly understood. In this study, we present a non-targeted LC-MS based metabolomic analysis in combination with a full-genome, high-throughput RNA sequencing (RNA-Seq) to reveal the metabolic effects and the subjacent regulatory pathways of exposing zebrafish embryos to BPA during the first 120 hours post-fertilization. We applied multivariate data analysis methods to extract biochemical information from the LC-MS and RNA-Seq complex datasets and to perform testable predictions of the phenotypic adverse effects. Metabolomic and transcriptomic data revealed a similar subset of altered pathways, despite the large difference in the number of identified biomarkers (around 50 metabolites and more than 1000 genes). These results suggest that even a moderate coverage of zebrafish metabolome may be representative of the global metabolic changes. These multi-omic responses indicate a specific metabolic disruption by BPA affecting different signaling pathways, such as retinoid and prostaglandin metabolism. The combination of transcriptomic and metabolomic data allowed a dynamic interpretation of the results that could not be drawn from either single dataset. These results illustrate the utility of -omic integrative analyses for characterizing the physiological effects of toxicants beyond the mere indication of the affected pathways. © 2017 Elsevier Ltd | This work was supported by the European Research Council under the European Union's Seventh Framework Programme (FP/ 2007-2013)/ERC Grant Agreement n. 320737. Some part of this study was also supported by a grant from the Spanish Ministry of Economy and Competitiveness (CTQ2014-56777-R). LNM was supported by a Beatriu de Pinos Postdoctoral Fellow (2013BP-B- 00088) awarded by the Secretary for Universities and Research of the Ministry of Economy and Knowledge of the Government of Catalonia and the Cofund programme of the Marie Curie Actions of the 7th R&D Framework Programme of the European Union. | Peer reviewed
Показать больше [+] Меньше [-]Bioconcentration of polycyclic musks in fathead minnows caged in a wastewater effluent plume Полный текст
2017
Lefebvre, Claudine | Kimpe, Linda E. | Metcalfe, Christopher D. | Trudeau, Vance L. | Blais, Jules M.
The synthetic polycyclic musks HHCB (Galaxolide®) and AHTN (Tonalide®) were monitored in fathead minnows (FHMs) caged for a month at various locations in the North Saskatchewan River (NSR), upstream and downstream of the Gold Bar wastewater treatment plant that serves the city of Edmonton, AB, Canada. In addition, the distribution of these musk compounds in the river was predicted using the fugacity-based Quantitative Water Air Sediment Interface (QWASI) model. In FHMs caged 0.15 km downstream of the wastewater outfall, mean concentrations of HHCB and AHTN were 7.4 and 0.4 μg g−1 wet weight, respectively. These are among the highest reported concentrations of these musk compounds in fish exposed to treated wastewater. The musk concentrations in FHMs were significantly lower further downstream of the outfall. High bioconcentration factors (BCFs) in FHMs that exceeded 104 higher than estimated concentrations in water indicated that there were low rates of biotransformation of the musks in the fish. In the FHMs caged at the site closest to the wastewater outfall, HHCB concentrations in FHMs were comparable to the body burdens that have been reported to moderate expression of vitellogenin in female rainbow trout, indicating that fish in the NSR downstream of the wastewater outfall may be at risk of anti-estrogenic effects. The QWASI model applied to six individual river sections of the NSR predicted that the largest fluxes of HHCB and AHTN would be for downstream transport in water, which explains why FHMs accumulated elevated concentrations of the musks at the furthest downstream site, 9.9 km from the wastewater discharge.
Показать больше [+] Меньше [-]Effects of the amendment of biochars and carbon nanotubes on the bioavailability of hexabromocyclododecanes (HBCDs) in soil to ecologically different species of earthworms Полный текст
2017
Li, Bing | Zhu, Hongkai | Sun, Hongwen | Xu, Jiayao
Biochar is a promising material used in soil amendment and carbon nanotubes may enter soil due to its increasing application. These carbonaceous materials may change the bioavailability of pollutants in soil. In this concern, 0.5% w/w multi-walled carbon nanotubes (MWCNTs) and 3 corn-straw biochars acquired at different pyrolyzing temperatures were used in soil amendment and their influences on the bioavailability of hexabromocyclododecanes (HBCDs), a brominated flame retardant, to 2 ecologically different earthworm species were studied. The amendment of 4 carbonaceous materials all reduced the bioaccumulation of HBCDs in earthworms by 18.2%–67.3%, which varied depending on the type of carbonaceous materials and the pyrolyzing temperature of biochars. The reduction in HBCDs uptake by Eisenia fetida (an epigeic species) was greater than by Metaphire guillelmi (an anecic species). The 2 earthworm species both showed bioaccumulative selectivity on certain HBCD diastereoisomer and enantiomer in the amended soils, which was similar to that in the control soil. Moreover, Tenax-assisted HBCDs desorption test was carried out for the simulation of their bioavailability. The rapid desorption fraction (Frap), total desorption (15 d), and 24 h desorption all correlated well with the uptake of HBCDs in the earthworms, suggesting that the 24 h-desorption, due to its easy availability, can be a good proxy to predict the bioavailability of HBCDs to earthworms in soil.
Показать больше [+] Меньше [-]Health conditions in rural areas with high livestock density: Analysis of seven consecutive years Полный текст
2017
van Dijk, Christel E. | Zock, Jan-Paul | Baliatsas, Christos | Smit, Lidwien A.M. | Borlée, Floor | Spreeuwenberg, Peter | Heederik, Dick | Yzermans, C Joris
Previous studies investigating health conditions of individuals living near livestock farms generally assessed short time windows. We aimed to take time-specific differences into account and to compare the prevalence of various health conditions over seven consecutive years. The sample consisted of 156,690 individuals registered in 33 general practices in a (rural) area with a high livestock density and 101,015 patients from 23 practices in other (control) areas in the Netherlands. Prevalence of health conditions were assessed using 2007–2013 electronic health record (EHR) data. Two methods were employed to assess exposure: 1) Comparisons between the study and control areas in relation to health problems, 2) Use of individual estimates of livestock exposure (in the study area) based on Geographic Information System (GIS) data. A higher prevalence of chronic bronchitis/bronchiectasis, lower respiratory tract infections and vertiginous syndrome and lower prevalence of respiratory symptoms and emphysema/COPD was found in the study area compared with the control area. A shorter distance to the nearest farm was associated with a lower prevalence of upper respiratory tract infections, respiratory symptoms, asthma, COPD/emphysema, allergic rhinitis, depression, eczema, vertiginous syndrome, dizziness and gastrointestinal infections. Especially exposure to cattle was associated with less health conditions. Living within 500m of mink farms was associated with increased chronic enteritis/ulcerative colitis. Livestock-related exposures did not seem to be an environmental risk factor for the occurrence of health conditions. Nevertheless, lower respiratory tract infections, chronic bronchitis and vertiginous syndrome were more common in the area with a high livestock density. The association between exposure to minks and chronic enteritis/ulcerative colitis remains to be elucidated.
Показать больше [+] Меньше [-]Bioaccumulation and trophic transfer of pharmaceuticals in food webs from a large freshwater lake Полный текст
2017
Xie, Zhengxin | Lü, Guanghua | Yan, Zhenhua | Liu, Jianchao | Wang, Peifang | Wang, Yonghua
Pharmaceuticals are increasingly detected in environmental matrices, but information on their trophic transfer in aquatic food webs is insufficient. This study investigated the bioaccumulation and trophic transfer of 23 pharmaceuticals in Taihu Lake, China. Pharmaceutical concentrations were analyzed in surface water, sediments and 14 aquatic species, including plankton, invertebrates and fish collected from the lake. The median concentrations of the detected pharmaceuticals ranged from not detected (ND) to 49 ng/L in water, ND to 49 ng/g dry weight (dw) in sediments, and from ND to 130 ng/g dw in biota. Higher concentrations of pharmaceuticals were found in zoobenthos relative to plankton, shrimp and fish muscle. In fish tissues, the observed pharmaceutical contents in the liver and brain were generally higher than those in the gills and muscle. Both bioaccumulation factors (median BAFs: 19–2008 L/kg) and biota−sediment accumulation factors (median BSAFs: 0.0010–0.037) indicated a low bioaccumulation potential for the target pharmaceuticals. For eight of the most frequently detected pharmaceuticals in food webs, the trophic magnification factors (TMFs) were analyzed from two different regions of Taihu Lake. The TMFs for roxithromycin, propranolol, diclofenac, ibuprofen, ofloxacin, norfloxacin, ciprofloxacin and tetracycline in the two food webs ranged from 0.28 to 1.25, suggesting that none of these pharmaceuticals experienced trophic magnification. In addition, the pharmaceutical TMFs did not differ significantly between the two regions in Taihu Lake.
Показать больше [+] Меньше [-]Integrating both interaction pathways between warming and pesticide exposure on upper thermal tolerance in high- and low-latitude populations of an aquatic insect Полный текст
2017
Op de Beeck, Lin | Verheyen, Julie | Stoks, Robby
Global warming and chemical pollution are key anthropogenic stressors with the potential to interact. While warming can change the impact of pollutants and pollutants can change the sensitivity to warming, both interaction pathways have never been integrated in a single experiment. Therefore, we tested the effects of warming and multiple pesticide pulses (allowing accumulation) of chlorpyrifos on upper thermal tolerance (CTmax) and associated physiological traits related to aerobic/anaerobic energy production in the damselfly Ischnura elegans. To also assess the role of latitude-specific thermal adaptation in shaping the impact of warming and pesticide exposure on thermal tolerance, we exposed larvae from replicated high- and low-latitude populations to the pesticide in a common garden rearing experiment at 20 and 24 °C, the mean summer water temperatures at high and low latitudes. As expected, exposure to chlorpyrifos resulted in a lower CTmax. Yet, this pesticide effect on CTmax was lower at 24 °C compared to 20 °C because of a lower accumulation of chlorpyrifos in the medium at 24 °C. The effects on CTmax could partly be explained by reduction of the aerobic scope. Given that these effects did not differ between latitudes, gradual thermal evolution is not expected to counteract the negative effect of the pesticide on thermal tolerance. By for the first time integrating both interaction pathways we were not only able to provide support for both of them, but more importantly demonstrate that they can directly affect each other. Indeed, the warming-induced reduction in pesticide impact generated a lower pesticide-induced climate change sensitivity (in terms of decreased upper thermal tolerance). Our results indicate that, assuming no increase in pesticide input, global warming might reduce the negative effect of multiple pulse exposures to pesticides on sensitivity to elevated temperatures.
Показать больше [+] Меньше [-]First “charosphere” view towards the transport and transformation of Cd with addition of manure derived biochar Полный текст
2017
Wang, Lu | Meng, Jun | Li, Zhangtao | Liu, Xingmei | Xia, Fang | Xu, Jianming
The specific area between biochar and soil surfaces is termed the “charosphere”, which is analogous to the rhizosphere between plant roots and soil. Physicochemical properties of charosphere soil differ from natural soil. A double-layer mesh bag experiment was conducted to separate the charosphere soil (>2 mm) from biochar (derived from manure pyrolyzed at 300, 500, 700 °C) and the bulk soil. A 95-day experiment determined the availability, total concentration and speciation of Cd in charosphere soil and the total and available Cd in biochar. The availability of Cd decreased in the charosphere soils. Total Cd concentration increased in the biochars but decreased in charosphere soil, suggesting that Cd might transfer from charosphere soil to biochar. Cd in the acid soluble fraction decreased by 25–40% in different biochars while it increased in residue fraction, indicating that Cd tends to be more stable in charosphere soil. Instrumental analysis using SEM, FTIR were performed to provide further evidence of the transport of Cd and to enable interpretation of the mechanisms involved. The phenomena that Cd concentrations change markedly in the charosphere inspires a novel research perspective towards the study of transport and transformation of heavy metals in soil after biochar application.
Показать больше [+] Меньше [-]Detoxification of hexavalent chromate by growing Paecilomyces lilacinus XLA Полный текст
2017
Xu, Xingjian | Xia, Lu | Chen, Wenli | Huang, Qiaoyun
In the study, the capability of Paecilomyces lilacinus XLA (CCTCC: M2012135) to reduce Cr6+ and its main antagonistic mechanisms to Cr6+ were experimentally evaluated. Activated growing fungus XLA efficiently reduced over 90% Cr6+ in the media with Cr6+ concentration below 100 mg L−1 at pH 6 after 14 days. After 1-day exposure to 100 mg L−1 Cr6+, nearly 50% of Cr6+ was reduced. Moreover, SO42− stimulated Cr6+ reduction, whereas other interferential ions inhibited Cr6+ reduction. The interaction mechanisms between XLA and Cr6+ mainly involve biotransformation, biosorption, and bioaccumulation, as detected by electron microscopy and chemical methods. The lower concentrations of Cr6+ (5 and 50 mg L−1) stimulated the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH) level in XLA, respectively, but the higher concentration of Cr6+ (150 mg L−1) decreased the enzymatic activities and GSH concentration. The results implied that SOD, CAT and GSH were defensive guards to the oxidant stress produced by Cr6+. All these extracellular/intracellular defense systems endowed XLA with the ability to resist and detoxify Cr6+ by transforming its valent species. The fungus XLA could efficiently reduce Cr6+ under different environmental conditions (pH, interferential ions, and concentration). Moreover, XLA could endure the high concentration of Cr6+ probably due to its high biotransformation capability of Cr6+ and intracellular antioxidant systems for the detoxification of ROS generated by external Cr6+. All these results suggested that the fungus XLA can be applied to remediation of Cr6+-contaminated environments.
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