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Mobile monitoring of particulate matter: State of art and perspectives Full text
2016
Gozzi, Fernando | Della Ventura, Giancarlo | Marcelli, A.
Due to the socio-economic impact and the consequences on human health, the pollution associated to Particulate Matter (PM) represents one of the main emergences at a global scale. For these reasons, in the last decade we assisted to a continuously increasing interest in the mobile monitoring of PM on a regional and a local scale. Here we summarize the current status in this field, outlining the critical issues and the perspectives. The growing availability of instruments designed and optimized to the real-time monitoring of the air quality, considerably increased the spatial and temporal resolution of available datasets, actually improving air pollution maps and forecast models. However, several issues are still unresolved, particularly in terms of data representativeness. Indeed, the future PM monitoring devices have to be designed to support the decisional process but also the management of environmental emergencies in urban and industrial areas. The future of these devices is certainly the development of compact systems that will make possible a real-time characterization of size distribution, morphology, and chemical composition of the airborne particles.
Show more [+] Less [-]Spatial variation and provenance of atmospheric trace elemental deposition in Beijing Full text
2016
Zheng, Xiaoxia | Guo, Xiaoyu | Zhao, Wenji | Shu, Tongtong | Xin, Yanan | Yan, Xing | Xiong, Qiulin | Chen, Fantao | Lv, Ming
Atmospheric dry deposition samples were collected in urban and suburban areas of Beijing during a coal-burning period. Chemical characteristics of lanthanoid elements (La–Lu) and five heavy metals (Cr, Co, Mo, Cd, and Pb) were analyzed to determine the variation in spatial scale and deposition provenances. Factor analysis and ternary diagrams were used to identify principle pollution sources. The LaCeSm ternary diagram was used to identify oil refineries using fluid catalytic converters and steel plants, but could not differentiate crustal materials. Lanthanoid characteristic parameters showed similarity between deposition and soil in the local and southwest area in the vicinity of Beijing. Analysis of the five heavy metals enabled discrimination of contaminants originating from human activities. Cd, Pb, and Mo were found to originate from vehicular traffic, whereas Co and Cr originated from industrial emissions and coal combustion. Discriminant analysis established the causes of spatial variation. The result shows that Co, Mo, and Pb can mark the differences between urban and suburban sites. From the PbMoCo plot, it was inferred that the different chemical characters are mainly due to the differing origins of depositions. Deposition samples in suburban areas are principally influenced by soil, chimney soot, and fertilizer, whereas those in urban area are mainly affected by traffic emissions.
Show more [+] Less [-]Determination of ambient air concentrations and personal exposure risk levels of outdoor workers to carbonyl compounds and BTEX in the inner city of Bangkok, Thailand Full text
2016
Kanjanasiranont, Navaporn | Prueksasit, Tassanee | Morknoy, Daisy | Tunsaringkarn, Tanasorn | Sematong, Saowanee | Siriwong, Wattasit | Zapaung, Kalaya | Rungsiyothin, Anusorn
The ambient and personal air concentrations of benzene, toluene, ethylbenzene and xylenes (BTEX) and carbonyl compounds (CCs) were investigated in Pathumwan district, Bangkok (Thailand), a congested area with a high level of traffic-related air pollution. The potential health risk of three representative groups of street workers (street vendors, motorcycle taxi driver and security guards) exposed to these substances was estimated. The personal air exposure and ambient air samples were collected in the rainy (September 2012) and summer (March 2013) seasons. The 8-h average formaldehyde and acetaldehyde exposure levels for both personal and ambient air concentrations were found to be the major CCs. The highest mean ambient air level of formaldehyde (20.1 μg/m3) was found at the roadside at a busy intersection next to department stores. The highest level of acetaldehyde (9.17 μg/m3) was found in a location with a high traffic load close to the hospital and university. For BTEX, the greatest average concentration was observed around the site located near a bus stop (45.5 μg/m3). In terms of the personal exposure concentrations of CCs and BTEX, no statistically significant differences were found among all sampled locations for street vendors and motorcycle taxi drivers. With respect to the health risk assessment, at a 95% confidence interval (CI) of cancer risk, benzene posed the highest risk followed by formaldehyde and then acetaldehyde (5.36E-06–1.48E-05, 5.58E-06–1.91E-05 and 1.03E-05–5.93E-05 for street vendors, motorcycle taxi driver and security guards) while the 95% CI non-cancer risk values were at an acceptable level. Nevertheless, there were no significant differences in the total cancer risk among the different groups of workers. From the health risk assessment, benzene and formaldehyde were the major traffic related air pollutants that likely affected the human health in this area.
Show more [+] Less [-]Measurement of aerosol nanoparticles from a combustion particle generator by using three types of dilutors Full text
2016
Lee, Byung Uk | Bae, Gwi Nam
Ultrafine aerosol nanoparticles created from combustion were measured by using three types of dilutors: a simple mixing dilutor, an ejector dilutor, and a rotational disk dilutor. The original particle size distribution from combustion was compared to the estimated distribution from these dilutors. The results showed that ultrafine aerosol nanoparticles maintained their particle size distribution, while particle concentrations decreased 10–20 fold in the dilution processes. Therefore, the dilutors not only diluted the aerosol nanoparticle concentration to the level of the measurement devices, but also helped estimate the shape of aerosol particle size distribution, particularly for ultrafine aerosol nanoparticles from combustion.
Show more [+] Less [-]The monetary valuation of acute respiratory illness from air pollution in Turkey Full text
2016
Ara, Shihomi | Tekeşin, Cem
A contingent valuation study is conducted in three locations in Turkey using a total of 1362 observations to elicit willingness to pay (WTP) to avoid the acute respiratory illness (three days of severe coughing and throat pain). This is the first research of this kind in Turkey, and also one of a few studies conducted in developing countries. Median WTPs are estimated as 65, 51, and 83 PPP-adjusted 2012 USD for Afsin-Elbistan, Kutahya-Tavsanli and Ankara, respectively. Income elasticities of WTP are derived as 0.8 for Afsin-Elbistan and tested statistically indifferent from 1.0 for Kutahya-Tavsanli, and Ankara, and are found to be greater than the cases in existing studies conducted both in developed and developing countries. We also find that 60 to 90 percent of WTP are devoted for avoiding pain and discomfort/restricted activity days, and much less weights are given for avoiding possible financial losses. As for the determinants of WTP, university graduates, those who have experienced coughing within one month, have spent out-of-pocket medical expenses and actually lost some part of their income due the last experienced minor symptoms are willing to pay more to avoid the future acute respiratory illness while women and the household using coal as the main source of home-heating are willing to pay less in one or more study areas. New air quality standard for PM10 (transition from 150 μg/m3 to 40 μg/m3 by 2019) causes the reductions in minor respiratory symptoms by 11, 8, and 4.4 per person, and the resulting welfare gains are calculated as 157 million, 123 million, and 1464 million PPP-adjusted 2012 USD for Afsin-Elbistan, Kutahya-Tavsanli and Ankara, respectively.
Show more [+] Less [-]Islands in the oil: Quantifying salt marsh shoreline erosion after the Deepwater Horizon oiling Full text
2016
Turner, R Eugene | McClenachan, Giovanna | Tweel, Andrew W.
Qualitative inferences and sparse bay-wide measurements suggest that shoreline erosion increased after the 2010 BP Deepwater Horizon (DWH) disaster, but quantifying the impacts has been elusive at the landscape scale. We quantified the shoreline erosion of 46 islands for before and after the DWH oil spill to determine how much shoreline was lost, if the losses were temporary, and if recovery/restoration occurred. The erosion rates at the oiled islands increased to 275% in the first six months after the oiling, were 200% of that of the unoiled islands for the first 2.5years after the oiling, and twelve times the average land loss in the deltaic plain of 0.4%y−1 from 1988 to 2011. These results support the hypothesis that oiling compromised the belowground biomass of the emergent vegetation. The islands are, in effect, sentinels of marsh stability already in decline before the oil spill.
Show more [+] Less [-]Metabolic performance of the coral reef fish Siganus guttatus exposed to combinations of water borne diesel, an anionic surfactant and elevated temperature in Indonesia Full text
2016
Baum, G. | Kegler, P. | Scholz-Böttcher, B.M. | Alfiansah, Y.R. | Abrar, M. | Kunzmann, A.
Metabolic performance of the coral reef fish Siganus guttatus exposed to combinations of water borne diesel, an anionic surfactant and elevated temperature in Indonesia Full text
2016
Baum, G. | Kegler, P. | Scholz-Böttcher, B.M. | Alfiansah, Y.R. | Abrar, M. | Kunzmann, A.
Jakarta Bay in Indonesia and its offshore island chain, the Thousand Islands, are facing extreme pollution. Surfactants and diesel-borne compounds from sewage and bilge water discharges are common pollutants. However, knowledge of their effects on reef fish physiology is scarce. This study investigated combined and single effects of a) the water accommodated fraction of diesel (WAF-D, determined by ƩEPA polycyclic aromatic hydrocarbons (PAHs)) and b) the surfactant linear alkylbenzene sulfonate (LAS) on metabolic performance of the coral reef fish Siganus guttatus. Responses to combinations of each pollutant with elevated temperature (+3°C) were determined. Short-term exposure to WAF-D led to a significant decrease in standard metabolic rates, while LAS led to an increase. During combined exposure, metabolic depression was observed. Effects of pollutants were not amplified by elevated temperature. This study highlights the need to reduce import of these pollutants and to avoid negative long-term effects on fish health.
Show more [+] Less [-]Effects of hypoxia caused by mussel farming on benthic foraminifera in semi-closed Gamak Bay, South Korea Full text
2016
Lee, Yeon Gyu | Jeong, Da Un | Lee, Jung Sick | Choi, Yang Ho | Lee, Moon-ok
Seawater monitoring and geochemical and benthic foraminiferal analysis of sediments were conducted to identify the effects of hypoxia created by a mussel farm on benthic foraminifera in a semi-closed bay. Extremely polluted reductive conditions with a high content of organic matter (OM) at >12.0% and oxygen minimum zones (OMZs) with dissolved oxygen (DO) <0.4mg∙L–1 were formed below the mussel farm in the northwest area of Gamak Bay, and gradually diffused toward the south. Highly similar patterns of variation were observed in species diversity, abundance frequency, and benthic foraminiferal assemblage distributed from Elphidium subarcticum–Ammonia beccarii in the northwest area through E. subarcticum–A. beccarii–Trochammina hadai, E. subarcticum–A. beccarii–Elphidiumclavatum, and E. clavatum–Ammonia ketienziensis in the southern area. These phenomena were caused by hydrodynamics in the current water mass. It was thought that E. subarcticum is a bioindicator of organic pollution caused by the mussel farm.
Show more [+] Less [-]Bioaugmentation strategy employing a microbial consortium immobilized in chitosan beads for oil degradation in mesocosm scale Full text
2016
Dellagnezze, B.M. | Vasconcellos, S.P. | Angelim, A.L. | Melo, V.M.M. | Santisi, S. | Cappello, S. | Oliveira, V.M.
A bacterial consortium composed by four metagenomic clones and Bacillus subtilis strain CBMAI 707, all derived from petroleum reservoirs, was entrapped in chitosan beads and evaluated regarding hydrocarbon degradation capability. Experiments were carried out in mesocosm scale (3000L) with seawater artificially polluted with crude oil. At different time intervals, mesocosms were sampled and subjected to GC-FID and microbiological analyses, as total and heterotrophic culturable bacterial abundance (DAPI and CFU count), biological oxygen demand (BOD) and taxonomic diversity (massive sequencing of 16S rRNA genes). The results obtained showed that degradation of n-alkane hydrocarbons was similar between both treatments. However, aromatic compound degradation was more efficient in bioaugmentation treatment, with biodegradation percentages reaching up to 99% in 30days. Community dynamics was different between treatments and the consortium used in the bioaugmentation treatment contributed to a significant increase in aromatic hydrocarbon degradation.
Show more [+] Less [-]Heavy metal accumulation in surface sediments at the port of Cagliari (Sardinia, western Mediterranean): Environmental assessment using sequential extractions and benthic foraminifera Full text
2016
Schintu, Marco | Marrucci, Alessandro | Marras, Barbara | Galgani, François | Buosi, Carla | Ibba, Angelo | Cherchi, A. (Antonietta)
Superficial sediments were taken at the port of Cagliari (Sardinia, Italy), which includes the oil terminal of one of the largest oil refineries in the Mediterranean. Significant trace metal concentrations were found in the whole port area. Sequential extraction of metals from the different sediment fractions (BCR method) showed a higher risk of remobilisation for Cd, which is mostly bound to the exchangeable fraction. Foraminiferal density and richness of species were variable across the study area. The living assemblages were characterized by low diversity in samples collected close to the port areas. Ammonia tepida and bolivinids, which were positively correlated with concentrations of heavy metals and organic matter content, appeared to show tolerance to the environmental disturbance. The sampling sites characterized by the highest values of biotic indices were located far from the port areas and present an epiphytic and epifaunal biocoenosis.
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