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In situ biomonitoring of air quality in rural and urban environments of Mexico Valley through genotoxicity evaluated in wild plants Полный текст
2017
Gómez-Arroyo, Sandra | Cortés-Eslava, Josefina | Loza-Gómez, Paola | Arenas-Huertero, Francisco | de la Mora, Michel Grutter | Morton Bermea, Ofelia
Air pollution is one the main causes of DNA damage in living organisms. Continuous exposure to the complex mixture of gases of polluted atmospheres affects health in many ways. Sentinel organisms are good biological models to assess the genotoxic damage caused by various chemicals such as atmospheric pollutants.In this study the plant species Taraxacum officinale and Robinsonecio gerberifolius were exposed during 2015, in the dry and rainy seasons, for 0, 2, 4 and 6 weeks to two different atmospheres of Mexico Valley, one rural in Altzomoni atmospheric observatory (ALTZ) and other urban in the atmospheric observatory of Centro de Ciencias de la Atmósfera (CCA), located in Universidad Nacional Autónoma de México (UNAM).Leaves of exposed plants were processed to analyze genotoxic damage by single-cell gel electrophoresis. To found any relation, the presence of pollutants in the atmosphere of both sites was analyzed with a Cavity Ring-Down Spectrometer (CRDS) and in the leaves the presence of heavy metals with an inductively coupled plasma mass spectrometer.Single-cell gel electrophoresis results showed higher damage in the leaves exposed to higher pollution in the UNAM atmospheric station in comparison to the ALTZ and controls, which was maintained in growth chambers under controlled conditions. Significant differences between rainy and dry seasons were found. Chemical analysis showed a significant increase in various heavy metals, especially in rainy season in both exposure sites. Increased DNA damage observed in both plant species at CCA station could be caused by accumulation trough six weeks.
Показать больше [+] Меньше [-]The estimation for ballast water discharged to China from 2007 to 2014 Полный текст
2017
Zhang, Xiaofang | Bai, Mindong | Tian, Yiping | Du, Huan | Zhang, Zhitao
Ballast water has been identified as one of the main causes for worldwide transfer of non-indigenous marine species. The volume and source of ballast water are the fundamental elements for an evaluation of the risk posed. However, it is difficult to obtain the volume of ballast water discharged to China, because of the absence of information platform, and until now there is no public report. In this paper, the total volume of ballast water discharged to China and Chinese five major port-groups were estimated. Results showed: the total volume of ballast water exhibited a trend of slow increase from 2007 to 2014, and reached 311 million tons in 2014. Yangtze River Delta received the highest volume of ballast water among all port-groups. The information provided in this research may play an important role in helping policy decision-makers manage such coastal discharges.
Показать больше [+] Меньше [-]Particle dry deposition of polycyclic aromatic hydrocarbons and its risk assessment in a typical coal-polluted and basin city, northern China Полный текст
2017
He, Qiusheng | Zhang, Lu | Cui, Yang | Cheng, Mingchao | Guo, Lili | Liu, Ming | Chen, Laiguo
Atmospheric dry deposition is a major pathway of pollutants removal from the atmosphere to the water and soil ecosystem. Polycyclic aromatic hydrocarbons (PAHs) in Taiyuan, China, are one class of the most hazardous air pollutants due to the high emission intensity from coal consumption. To better understand the PAHs removing from the atmosphere, 16 USEPA priority PAHs (except for naphthalene) in the particle dry deposition samples were detected from August 2013 to November 2014 at an urban site in Taiyuan. Dry deposition fluxes of particles were estimated as 157.44–358.17 mg/(m2·d), with the highest value in spring and lowest in autumn. Particle dry deposition fluxes of ∑15-PAHs ranged from 2436.20 to 14,967.36 ng/(m2·d), and was the highest in winter and lowest in summer. Higher PAHs particle dry deposition fluxes were related to higher PAHs emission, lower air temperature, less precipitation as well as wind speed. Overall dry deposition velocities of 15-PAHs were 0.056 ± 0.027 cm/s in winter and 0.42 ± 0.050 cm/s in summer, respectively, and high molecular weight PAHs showed low dry deposition velocities. Positive matrix factorization model's results indicated that coking, vehicle exhaust, coal combustion were the primary PAHs sources in particle dry deposition samples, accounting for 18.64%, 26.54% and 54.82% of total PAHs, respectively. The toxic equivalent concentrations (BaPeq) of ∑15-PAHs in particle dry deposition samples was in the range of 0.69–2.94 μg/g, which might be a good explanation to high soil PAHs concentrations reported in Shanxi province, China. Furthermore, this work could prove the significance of coal combustion, and related pollution control works are needed to conduct to alleviate the PAHs pollution situation.
Показать больше [+] Меньше [-]What are the factors driving long-term changes of the suprabenthos in the Seine estuary? Полный текст
2017
Pezy, Jean-Philippe | Baffreau, Alexandrine | Dauvin, Jean-Claude
A Before/During/After Control-Impact approach is used to assess the effects of Port 2000 on the suprabenthos in the North Channel (NC) of the Seine estuary during the period from September 2001 to October 2015. Since the beginning of Port 2000 construction (2002–2005), the NC is affected by an increase of salinity (marine influence) and input of sand. The suprabenthos changes are mainly characterised by an increase in species richness in the upper part of the NC and a decrease in species density and biomass of the dominant mysid species over time. Multiple stressors (natural and anthropogenic) have been operating simultaneously (hydrological changes, construction of Port 2000, supplementary dredging) rendering the interpretation of the biological changes difficult. Thus, the present results evidenced a combination of changes in the Seine Estuary not only attributed to the impact of the Port 2000 construction.
Показать больше [+] Меньше [-]Occurrence, source and ecological assessment of baseline hydrocarbons in the intertidal marine sediments along the shoreline of Douglas Channel to Hecate Strait in British Columbia Полный текст
2017
Yang, Zeyu | Hollebone, Bruce P. | Laforest, Sonia | Lambert, Patrick | Brown, Carl E. | Yang, Chun | Shah, Keval | Landriault, Mike | Goldthorp, Michael
The occurrence, source and ecological assessment of baseline hydrocarbons in the intertidal zone along the northern British shoreline were evaluated based on analyzing total petroleum hydrocarbons (TPH), n-alkanes, petroleum related biomarkers such as terpanes and steranes, and polycyclic aromatic hydrocarbons (PAHs) including non-alkylated and alkylated homologues (APAHs). The TPH levels, n-alkanes, petroleum biomarkers and PAHs in all the sampling sites, except for Masset Harbor/York Point at Gil Island were low, without obvious unresolved complex mixture (UCM) and petroleum contamination input. Specifically, n-alkanes showed a major terrestrial plants input; PAHs with abundant non-alkylated PAHs but minor APAHs showed a major pyrogenic input. However, obvious petroleum-derived hydrocarbons have impacted Masset Harbor. A historical petroleum input was found in York Point at Gil Island, due to the presence of the low level of petroleum biomarkers. Ecological assessment of 13 non-alkylated PAHs in Masset Harbor indicated no potential toxicity to the benthic organisms.
Показать больше [+] Меньше [-]A novel approach for monitoring vertical profiles of boundary-layer pollutants: Utilizing routine news helicopter flights Полный текст
2017
Crosman, Erik T. | Jacques, Alexander A. | Horel, John D.
Air quality varies greatly in space and time across urban locales. However, criteria pollutants are typically monitored routinely at a relatively small number of surface sites within each metropolitan area, and routine vertical profiles of pollution are typically unavailable. We illustrate that a news helicopter provides an effective sensor platform to provide spatiotemporal analyses and vertical profiles of pollutant concentrations. We are unaware of any other air quality study that has utilized routine helicopter flights, despite the ubiquity of helicopters in urban environments across the world. Particulate and ozone concentration profiles have been collected since 2015 from sensors installed on a news helicopter that travels primarily over the metropolitan areas of northern Utah. The air quality data are retrieved in real time, archived, combined with surface-based observations, and disseminated in terms of time series and maps on a website for research, forecasting, and public awareness. Large vertical variations in particulate pollution concentrations were observed during the 2015–2016 winter associated with meteorological cold-air pool episodes. During the 2015 and 2016 summer seasons, ozone concentrations frequently exhibited complex spatial and temporal variations arising from many interrelated factors, including local terrain-forced circulations, lake breezes, and distant wildfires.
Показать больше [+] Меньше [-]Evaluation of AhR-agonists and AhR-agonist activity in sediments of Liaohe River protected areas, China Полный текст
2017
Zhang, Yun | Ke, Xin | Gui, Shaofeng | Wu, Xiaoqiong | Wang, Chunyong | Zhang, Haijun
A total of 9 sediment samples of Liaohe River protected areas were collected to evaluate aryl hydrocarbon receptor agonists (AhR-agonists) and AhR-agonist activity via chemical analysis and in vitro H4IIE cell bioassay. Results indicated that bioassay-derived 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (Bio-TEQs) ranged from 89.1 to 251.1pg/g dry weight. Concentrations of 16 EPA polycyclic aromatic hydrocarbons (PAHs), 12 dioxin-like polychlorinated biphenyls (PCBs), and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) ranged from 256.8 to 560.1ng/g, 79.2 to 416.2pg/g, and 199.6 to 538.4pg/g, respectively. According to potency balance analysis, TEQchems based on PAHs, PCBs, and PCDD/Fs could contribute 16.56% to 26.11% of Bio-TEQs. This could be explained by the potential existence of unidentified AhR-agonists and the potential non-additive interactions among AhR-agonists in sediment extracts. Through the different contributions to Bio-TEQs, this study confirms that PCDD/Fs were the main pollutants that induced significantly AhR-agonist activity in sediments of Liaohe River protected areas.
Показать больше [+] Меньше [-]Occurrence of antiparasitic pesticides in sediments near salmon farms in the northern Chilean Patagonia Полный текст
2017
Tucca, Felipe | Moya, Heriberto | Pozo, Karla | Borghini, Francesca | Focardi, S. (Silvano) | Barra, Ricardo
Growth of the aquaculture industry has triggered the need for research into the potential environmental impact of chemicals used by salmon farms to control diseases. In this study, the antiparasitic pesticides emamectin benzoate (EB), diflubenzuron (DI), teflubenzuron (TE), and cypermethrin (CP) were measured in sediments near salmon cages in southern Chile. Concentrations for EB were between 2.2 and 14.6ngg−1, while the benzoylphenyl ureas DI and TE were detected in the ranges of 0.1 to 1.2ngg−1 and 0.8 to 123.3ngg−1, respectively. These results were similar to data reported for the Northern Hemisphere. On the other hand, the pyrethroid CP was detected in higher concentrations, ranging from 18.0 to 1323.7ngg−1. According to reported toxicity data, this range represents a potential risk for benthic invertebrates. This report is the first baseline attempt at assessing antiparasitic pesticide levels in the Chilean Patagonia.
Показать больше [+] Меньше [-]Photodegradation of diclofenac in seawater by simulated sunlight irradiation: The comprehensive effect of nitrate, Fe(III) and chloride Полный текст
2017
Zhang, N. | Li, J.M. | Liu, G.G. | Chen, X.L. | Jiang, K.
Diclofenac is one of the most frequently detected pharmaceuticals in various aquatic environments. The photodegradation of diclofenac in the absence/presence of nitrate, Fe(III) and chloride, especially their interactions, were systematically studied. Under the study conditions, photodegradation rate was decreased with increasing nitrate, Fe(III) and chloride concentrations. Nitrate has an synergistic action for Fe(III). Nitrate and chloride have antagonistic effect. An antagonistic action is present between nitrate, Fe(III) and chloride. Moreover, a simple linear model which very well describes the results is given.
Показать больше [+] Меньше [-]Spatio-temporal variations in bloom of the red-tide dinoflagellate Karenia mikimotoi in Imari Bay, Japan, in 2014: Factors controlling horizontal and vertical distribution Полный текст
2017
Aoki, Kazuhiro | Kameda, Takahiko | Yamatogi, Toshifumi | Ishida, Naoya | Hirae, Sou | Kawaguchi, Mayumi | Syutou, Toshio
A massive bloom of the dinoflagellate Karenia mikimotoi appeared in 2014 in Imari Bay, Japan. Bloom dynamics and hydrographical conditions were examined by field survey. The bloom initially developed in the eastern area of Imari Bay, subsequently after rainfall during the neap tides, cell density exceeded over 10,000cellsml. Vertical distribution of K. mikimotoi was primarily controlled by the light intensity and secondarily by the water quality during the daytime. Almost all cell-density maxima occurred in depths with weak daytime light intensities of <300μmolm−2s−1. In some cases of weak light intensity, cell-density maxima occurred in depths with favorable hydrodynamic conditions for the growth. Spatially classified areas were identified by cluster analysis using the growth rate calculated from seawater temperature and salinity. This study quantitatively evaluated the environmental factors of the eastern area, where the bloom initially occurred, during the development of the bloom.
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