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Carbonyl concentrations from sites affected by emission from different fuels and vehicles Texte intégral
2014
Concentrations of carbonyl compounds were evaluated on places impacted by emissions from different fuels and vehicles. In order to evaluate the concentrations, four campaigns during the winter and summer of 2011 and 2012 were performed, inside a covered parking area in a commercial establishment where mainly gasohol and ethanol vehicles are in circulation. Also, measurements were done inside a semi–closed bus station, which is the direct source of emissions from heavy duty vehicles (i.e. buses) burning B3–diesel (3% biodiesel and 97% diesel). The results indicated that acetaldehyde is the main aldehyde emitted by light vehicles due to large use of ethanol in Brazil by these vehicles. In addition, the concentrations found in the bus station revealed that B3–diesel fuel increases the emissions of carbonyl compounds and that of acetaldehyde when compared with results from B0–diesel at same bus station. Possible impacts of changing diesel to B3–diesel indicate an increase of ozone formation. In terms of health, a lower impact was estimated considering only the changes in formaldehyde concentrations.
Afficher plus [+] Moins [-]Microplastic pollution in the Northeast Atlantic Ocean: Validated and opportunistic sampling Texte intégral
2014
Levels of marine debris, including microplastics, are largely un-documented in the Northeast Atlantic Ocean. Broad scale monitoring efforts are required to understand the distribution, abundance and ecological implications of microplastic pollution. A method of continuous sampling was developed to be conducted in conjunction with a wide range of vessel operations to maximise vessel time. Transects covering a total of 12,700km were sampled through continuous monitoring of open ocean sub-surface water resulting in 470 samples. Items classified as potential plastics were identified in 94% of samples. A total of 2315particles were identified, 89% were less than 5mm in length classifying them as microplastics. Average plastic abundance in the Northeast Atlantic was calculated as 2.46particlesm−3. This is the first report to demonstrate the ubiquitous nature of microplastic pollution in the Northeast Atlantic Ocean and to present a potential method for standardised monitoring of microplastic pollution.
Afficher plus [+] Moins [-]Radioactivity concentrations in mussel (Mytilus galloprovincialis) of Turkish Sea coast and contribution of 210Po to the radiation dose Texte intégral
2014
Kılıç, Önder | Belivermiş, Murat | Çotuk, Yavuz | Topçuoğlu, Sayhan
Radionuclides levels were determined in indigenous and transplanted mussels (Mytilus galloprovincialis) collected from Turkish marine environment. Radioactivity concentrations of 137Cs, 40K, 226Ra, 228Ra, 210Po and 210Pb were determined in the soft tissues of the mussel samples collected in Bosphorus Strait, Coasts of Black Sea, Marmara Sea and Aegean Sea. Mussel transplantation was carried out by using mussel cages in Levantine Sea coast since M. galloprovincialis did not naturally adapt along the coast. The average activity concentrations of 137Cs, 40K, 226Ra, 228Ra, 210Po and 210Pb in the coastline of Turkey were found to be 0.7±0.1, 469±24, 0.9±0.1, 1.0±0.1, 122±4 and 10.9±0.9Bqkg−1 in dry weight (dw), respectively. The average of 210Po/210Pb ratio was found to be ∼14. Total annual effective 210Po dose was calculated to be in the range of 0.25–3.30 μSv due to mussel consumption. Radioactivity and dose levels were compared with those of similar studies carried out in Mediterranean countries.
Afficher plus [+] Moins [-]The occurrence and ecological risks of endocrine disrupting chemicals in sewage effluents from three different sewage treatment plants, and in natural seawater from a marine reserve of Hong Kong Texte intégral
2014
Xu, Elvis G.B. | Liu, Shan | Ying, Guang-Guo | Zheng, Gene J.S. | Lee, Joseph H.W. | Leung, Kenneth M.Y.
We determined the concentrations of 12 endocrine disrupting chemicals (EDCs) in sewage effluents collected from three different sewage treatment plants (STPs) in Hong Kong, and found 4-nonylphenol (NP) and bisphenol A (BPA) were the most abundant EDCs. Effluent concentrations of NP and BPA were higher in dry season than in wet season, but opposite seasonal changes of NP were observed in receiving waters, probably due to the surface runoff. The two secondary STPs showed higher removal efficiency for these compounds than the preliminary STP, while having higher removal efficiency in wet season. Therefore, it is necessary to upgrade the preliminary STP and improve the EDC removal efficiency in dry season. Seawaters from the Cape D’ Aguilar Marine Reserve adjacent to these STPs also exhibited elevated NP levels with a hazard quotient >1. Furthermore, diluted effluents from the STPs elicited significant transcriptional responses of EDC-related genes in the marine medaka fish.
Afficher plus [+] Moins [-]Increased zooplankton PAH concentrations across hydrographic fronts in the East China Sea Texte intégral
2014
Hung, Chin-Chang | Ko, Fung-Chi | Gong, Gwo-Ching | Chen, Kuo-Shu | Wu, Jian-Ming | Chiang, Hsin-Lun | Peng, Sen-Chueh | Santschi, Peter H.
The Changjiang has transported large quantities of polycyclic aromatic hydrocarbons (PAHs) to the East China Sea (ECS), but information of these pollutants in zooplankton is limited. To understand PAHs pollution in zooplankton in the ECS, total concentrations of PAHs in zooplankton from surface waters were measured. Values of PAHs ranged from 2 to 3500ngm−3 in the ECS, with highest PAHs levels located at the salinity front between the Changjiang Diluted Water (CDW) and the mid-shelf waters. In contrast, concentrations of zooplankton PAHs in the mid-shelf and outer-shelf waters were significantly lower (2–23ngm−3) than those in the CDW. These results demonstrate that PAHs are conspicuously accumulated in zooplankton at the salinity front between the CDW and the mid-shelf waters. These higher levels of PAHs in zooplankton at the salinity front may be further biomagnified in marine organisms of higher trophic levels through their feeding activities.
Afficher plus [+] Moins [-]Chemical profiles of urban fugitive dust over Xi'an in the south margin of the Loess Plateau, China Texte intégral
2014
Zhang, Qian | Shen, Zhenxing | Cao, Junji | Ho, KinFai | Zhang, Renjian | Bie, Zengjun | Chang, Hairu | Liu, Suixin
Urban fugitive dust samples were collected to determine the chemical profiles of fugitive dust over Xi'an. Seventy eight samples were collected and divided into categories of paved road dust, construction dust, cement dust, and soil dust. Eighteen elements, including Na, Mg, Al, Si, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Ba, and Pb, and eight water–soluble inorganic ions, including Na+, Mg2−, Ca2−, NH4−, F−, Cl−, NO3− and SO42−, were measured. The most abundant elements in these urban dust samples were Al, Si, Ca, and Fe. Al, Si, K, and Ti and showed strong positive correlations with each other, indicating they are typical dust trace elements. In contrast, elements of Ca, Zn, As, and Pb had negative correlations to crustal elements. Si/Al, K/Al, Ti/Al, Mn/Al, and Fe/Al ratios varied insignificantly among these four samples types; these ratios are similar to the properties of loess, desert, and Gobi soil dust reported in previous studies. A significantly higher Ca/Al ratio was dominant in the chemical profile of the cement samples. In addition, high Pb/Al and Zn/Al ratios were detected in comparison with those in the Gobi soil, desert soil, and loess soil samples, which indicated that Pb/Al and Zn/Al ratios can be considered as markers of urban dust. To t a l water–soluble ions occupied only a small fraction (<5%) in the urban fugitive soil samples indicating that most of the materials in the fugitive dust were insoluble. Ca2+ and SO42− were the most abundant ions in all samples. Most of the Ca and K in the fugitive soil samples were in insoluble phases, which differ significantly in comparison with combustion sources. A strong correlation was observed between Ca2+ and estimated CO32− levels indicating that most of Ca2+ was in the form of CaCO3 rather than other calcium minerals in Xi’an fugitive dust.
Afficher plus [+] Moins [-]Atmospheric NH3 dynamics at a typical pig farm in China and their implications Texte intégral
2014
Xu, Wen | Zheng, Kun | Liu, Xuejun | Meng, Lingmin | Huaitalla, Roxana M. | Shen, Jianlin | Hartung, Eberhand | Gallmann, Eva | Roelcke, Marco | Zhang, Fusuo
This study investigated NH3 concentrations in and around a large–scale commercial pig farm with the so–called “gan qing fen” manure collection system near Beijing from April 2009 to August 2011. NH3 emissions from the fattening pig houses were calculated based on the heat balance method. Monthly concentrations of time–averaged NH3 in and near the pig house averaged 3 392 and 182μg m−3 and ranged from 1 044 to 7 514μg m−3 and 35.4 to 478μg m−3, respectively. Daily NH3 concentrations varied from 767 to 2 389μg m−3 in the pig house and 184 to 574μg m−3 outside. Time–averaged NH3 concentrations varied from 21.6 to 558μg m−3 within the farm while concentrations outside the farm ranged from 38.4μg m−3 at a distance of 10m to 14.0μg m−3 at a distance of 650m. Calculated average NH3 emission rates per pig were highest in summer and lowest in winter, 8.0±5.5 (average±standard deviation) and 2.0±0.4g day−1 pig−1, respectively. Average NH3 emission rates (normalized to 500kg live weight, expressed as AU) were highest during spring and summer (average 65.4±25.0 and 53.7±35.6 g day−1 AU−1) and lowest in autumn and winter (average 25.4±9.3 and 13.7±2.7g day−1 AU−1). Average NH3 emission per area (m2) from house was almost three times higher in summer (average 3.5±2.4g day−1 m−2) than in winter (average 1.1±0.3g day−1 m−2).
Afficher plus [+] Moins [-]RETRACTION: Energy direct inputs and greenhouse gas emissions of the main industrial trawl fishery of Brazil Texte intégral
2014
Port, Dagoberto | Alvarez Perez, Jose Angel | de Menezes, João Thadeu
This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy).This article has been retracted at the request of the Editor-in-Chief and the Authors.This paper has to be retracted as the authors have noticed a procedural error with regards to their data which affects the results and discussion of the paper. It is important to note that this is not considered to be the result of scientific misconduct, but rather honest errors by the authors.
Afficher plus [+] Moins [-]Environmental policy constraints for acidic exhaust gas scrubber discharges from ships Texte intégral
2014
Ülpre, H. | Eames, I.
Increasingly stringent environmental legislation on sulphur oxide emissions from the combustion of fossil fuels onboard ships (International Maritime Organization (IMO) Regulation 14) can be met by either refining the fuel to reduce sulphur content or by scrubbing the exhaust gases. Commonly used open loop marine scrubbers discharge warm acidic exhaust gas wash water into the sea, depressing its pH. The focus on this paper is on the physics and chemistry behind the disposal of acidic discharges in seawater.The IMO Marine Environment Protection Committee (MEPC 59/24/Add.1 Annex 9) requires the wash water to reach a pH greater than 6.5 at a distance of 4m from the point of discharge. We examine the engineering constraints, specifically size and number of ports, to identify the challenges of meeting regulatory compliance.
Afficher plus [+] Moins [-]Measuring bioavailable PAHs in estuarine water using semipermeable membrane devices with performance reference compounds Texte intégral
2014
Chang, Wan-Ting | Fang, Meng-Der | Lee, Chon-Lin | Brimblecombe, Peter
Bioavailable polycyclic aromatic hydrocarbon (PAH) concentrations in the estuarine water of Kaohsiung Harbor were measured using XAD-2 resin and semipermeable membrane devices (SPMDs) calibrated with performance reference compounds (PRCs). The sum of the PAH concentrations from XAD-2 resin (Cw) in the surface and bottom water samples was 6.63 and 9.58ngL−1, respectively. The variation in PAHs was higher in surface water. Cubic polynomial regressions using the sampling rate for five PRCs (Rs-PRC) provided estimated in situ sampling rates (Rs). The turbulent condition in the surface water was important in enhancing Rs; however, diffusion was relevant to the bottom water, which was less turbulent and showed decreasing Rs at high MW PAHs. The sum of the dissolved PAH concentrations estimated with the SPMDs (CSPMD) was 5.87 and 9.15ngL−1 in the surface and bottom water samples, respectively. The surface and bottom water PAHs were derived from different sources.
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