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Abstract  

Epiphytic bromeliadTillandsia usneoides was used as a biomonitor of metal atmospheric pollution in the city of São Paulo, Brazil. The samples were collected from an unpolluted area and were exposed for 8 weeks in 10 sites of the city and in a control site. The data obtained showed that the control site presented lower concentration for most elements analyzed and the highest concentrations of Na, Cl, Br, K. The highest concentrations of Zn, Cu and V were observed in stations submitted to industrial and vehicular sources. The results obtained for rare earth elements, Al, Fe, Mg, Mn, Rb and Sc indicate mineral dust origin. The elements Ba, As and Sb presented higher values in stations near streets with heavy traffic.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: Caijin Xiao, Guiying Zhang, Donghui Huang, Bangfa Ni, Cunxiong Liu, Yali Qin, Hongchao Sun, Pingsheng Wang, and Weizhi Tian

Abstract  

A total of 178 aerosol samples in two size fractions, PM10-2.5 (coarse) and PM2.5 (fine), were collected on nucleopore films using a Gent stacked filter unit sampler at the Graduate School of China Nuclear Industrial Group during May 2007 to November of 2009. Black carbon was determined by a reflectometer. A total of 16 elements, Mg, Al, S, Si, P, Cl, Ca, K, Ti, Mn, Fe, Ni, Cu, Zn, As and Pb, were determined by Particle Induced X-ray Emission. Mg, Al, Ca, K and Mn were also determined by Neutron Activation Analysis. Concentrations of all these elements were used to identify possible pollution sources and directions of the airborne particulate matter by means of softwares PMF and CPF. Some extraordinary events, such as sandstorms, firework and transboundary fire smoke were pinpointed by a combination of time series of multielement, relevant meteorological data and softwares Wind rose, Hysplit, and Google earth.

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Abstract  

The atmospheric pollution of São Paulo city is a serious problem due to the expansion of industrial area, increasing number of vehicles and population density. This work presents results obtained in the analysis of lichens collected in different sites of São Paulo city and in non-polluted areas of Atlantic Forest. Concentrations of twenty elements were determined in Canoparmelia texana species and comparisons were made between the results obtained in lichens from different sites. High concentrations of the elements As, Ba, Cd, Co, Cr, Fe, La, Mn, Sb and Zn were found for samples collected in sites located near industries and petrochemical plant. Br and Sb concentrations were also high in lichens from sites affected by vehicular emissions.

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Abstract  

k 0-Standardized INAA was applied to the determination of heavy elements in two lichen varieties of the speciesParmelia: caperata andsulcata. The aim was to find out differentiations between the two varieties concerning the accumulation of elements from the air. The samples were collected at about 70 locations randomly chosen in the whole country (Portugal). It was found a similar local variation for both species, between 20–25%. From the comparison it was observed thatParmelia sulcata accumulates larger amounts of most of the elements determined thanParmelia caperata; only Ca is more accumulated by thecaperata and Hg are similarly absorbed by both varieties. Therefore, it was concluded thatParmelia sulcata should be preferred as bioaccumulator when both varieties are present. Some pollution sources were identified, but the sampling net was too short to obtain an exhaustive identification. The quality control was made using NIST and IAEA reference materials: an accuracy of ±10% was found. The precision has also been estimated: it is better than 11% except for Hg (15%), Sr (13%), Ti (19%) and Mg (32%).

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Abstract  

The process of urbanization and industrialization during las two decades has resulted in increased level of air pollution causing hazards to human health. Instrumental neutron activation analysis (INAA) using short and long term irradiation has been employed for the determination of more than 30 elements in suspended particulate matter (SPM) from six metropolitan cities and three industrial surroundings. A comparison of mean elemental contents in dust particulates from commercial, industrial and residential zones of Delhi, Calcutta, Madras, Cochin, Bombay and Nagpur cities has shown wide variation in toxic pollutant (As, Br, Cr, Cu, Hg and Sb) concentrations. Coastal areas have shown higher concentrations of Na, K, Cl and Br. Highly industrialized Bombay showed highest levels of Br, Cl, Cr, Fe, Mg, P, Rb and Sc. Mean elemental contents in fugitive and ambient dust of a cement factory and thermal power station (both in central India) are widely different. SPM levels in fugitive dust of the two industrial surroundings are higher by an order of magnitude compared to ambient air. Analysis of ambient air dust from a paper mill showed highest concentrations of Hg, Sb and Zn. Elemental data have been compared with those of Urban Particulate Matter (SRM 1648), Coal Fly Ash (SRM 1633a) and Vehicle Exhaust Particulate (NIES No. 8) which were analysed for quality control. An attempt has been made to attribute the elemental contents to possible sources of origin.

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Abstract  

Hair samples collected from free living mammals common hare (Lepus europaeus Pall.), common vole (Microtus arvallis Pall.) and wood mouse (Apodemus sylvaticus L.) have been subjected to instrumental neutron activation analysis (INAA). up to 18 elements As, Au, Br, Ce, Co, Cr, Cu, Fe, Hg, K, La, Na, Sb, Sc, Se, Sm, Th and Zn have been determined in each hair sample. Animal hair samples from areas polluted by thermal power plants burning coal were taken and compared with hair samples from the animals living in relatively non-polluted control areas. The results show that animal hair samples from areas with higher level of pollution contain usually higher concentrations of toxic and essential elements as As, Co, Cr, Fe and Se. Muride rodents can be used for more detailed monitoring of environmental exposure than hare. Moreover, hair of common vole shows usually higher levels of contamination as compared with wood mouse, which could be explained by different compositions of feed. Animal hair has been shown to be a rather sensitive indicator of environmental exposure and INAA has proved to be a suitable analytical tool for this purpose.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: N. Spyrou, W. Arshed, A. Farooqi, G. Ibeanu, O. Akanle, C. Jeynes, O. Asubiojo, I. Obioh, E. Oluyemi, and A. Oluwole

Abstract  

Three nuclear and atomic-based techniques for elemental analysis of air-particulate samples are discussed in terms of their usefulness in an environmental monitoring and impact assessment programme, supported by the European Economic Community, in Nigeria. Instrumental neutron activation analysis (INAA) and proton induced X-ray emission (PIXE) analysis are compared with respect to the number of elements detected and the detection limits obtained for air-particulate matrices. The latter is used in conjunction with Rutherford backscattering spectrometry (RBS) in order to correct for variations in matrix composition. A scanning electron microprobe (SEM) with analytical facilities is also employed mainly for characterization of the air-particulates through measurement of particle size and morphology. The value of carrying out statistical analysis for differentiating between collection sites or sources of pollution is emphasised. Reference to results obtained from the analysis of air-particulates collected during the Harmattan season at Kano and Ife, separated by about 1000 km place the problem in context and serve to illustrate the requirements.

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Abstract  

The aim of this research was to enhance the use of nuclear analytical techniques for air pollution studies and to study the feasibility of the use of instrumental neutron activation analysis (INAA) as a routine monitoring tool to reveal environmental pollution sources. For the collection of air particulate samples, the Gent stacked filter unit, low volume sampler with Nucleopore membrane filters were used. Trace elements in samples collected at two suburban residential sites, Taejon and Wonju city in the Republic of Korea, were analyzed by INAA. Variations of the elemental concentrations were measured monthly and the enrichment factors were calculated for the fine (<2 μm EAD) and coarse size (2–10 μm EAD) fractions. The analytical data were treated statistically to estimate the relationship between the two variables, the concentrations of elements and the total suspended particulate matter. The results were used to describe the emission source and their correlation.

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Abstract  

Some metal contents of the freshwater isopod: Asellus aquaticus (Crustacea:Isopoda), collected from the pool of the botanical garden of Istanbul University(at the vicinity of old city center of Istanbul), were analysed, in orderto investigate urban metal pollution. The analysis of the homogenized sampleof isopods indicated that it contained K, Ca, Mn, Fe, Cu, Ni, Zn, Pb, Br,Rb, Sr, Y, Zr, Ba, Cd, Cs and Hg in different amounts. The results were comparedwith those of other isopods and various organisms.

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Abstract  

For air pollution monitoring, about 1300 airborne particulate matter samples were collected by using a low volume air sampler and a polycarbonate filter at two sampling sites in an urban region, Daejeon, the middle of Korea from 2003 to 2006. Mass concentrations of the black carbon were measured using a smoke stain reflectometer. The concentrations of 24 elements in the collected samples were analyzed by using instrumental neutron activation analysis, and its temporal trends and enrichment factors were investigated under different environmental conditions. Analytical control was carried out by using certified reference materials.

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