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Abstract  

The lichen Ramalina celastri (Spreng.) Krog. & Swinsc. was used to study trace-element atmospheric pollution in Córdoba (Argentina). 38 samples from a 1999 campaign were analyzed by NAA and a number of physiological parameters was determined. In first-ever comparisons, no correlations were found between altitude, physiological parameters and determined elements, which allowed the full comparison of element data in lichen samples throughout the whole survey area. After the application of Monte Carlo assisted factor analysis to the elemental matrix, five source profiles were found and mapped. The attribution of the sources is discussed.

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Abstract  

This study deals with the accumulation dynamics of the long-lived fission product technetium (99Tc) in duckweed. Duckweed serves as model for aquatic plants, because of its representative foliar uptake for 99Tc. This study shows that 99Tc is irreversibly accumulated and distributed over cytoplasm, chloroplasts and mitochondria. Autoradiography showed that 99Tc was not transported to new biomass. Irreversible storage of 99Tc in plant biomass means that steady-state situations cannot be interpreted as a balance between uptake and elimination of 99Tc, but that 99Tc continuously builds up in each single duckweed plant and overall Tc concentrations are averaged over new biomass.

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Abstract  

Transplants of the epiphytic lichen Parmelia sulcata were suspended in nylon bags within a rectangle of 15 km wide and 25 km long on a grid 2.5 km'2.5 km in the Sado estuary region. The transplants were oriented towards the wind (F) and opposing the wind (T) and were collected after 3, 6 and 9 months of exposure. Samples were analyzed by INAA and PIXE. Source identification was made by Monte Carlo Target Transformation Factor Analysis (MCTTFA) using three different combinations of data (all data, F data and T data). Five factors were identified for all the combinations performed. For two factors, F and T differentiation was observed.

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Abstract  

A biomonitoring study, using transplanted lichens Flavoparmelia caperata, was conducted to assess the indoor air quality in primary schools in urban (Lisbon) and rural (Ponte de Sor) Portuguese sites. The lichens exposure period occurred between April and June 2010 and two types of environments of the primary schools were studied: classrooms and outdoor/courtyard. Afterwards, the lichen samples were processed and analyzed by instrumental neutron activation analysis (INAA) to assess a total of 20 chemical elements. Accumulated elements in the exposed lichens were assessed and enrichment factors (EF) were determined. Indoor and outdoor biomonitoring results were compared to evaluate how biomonitors (as lichens) react at indoor environments and to assess the type of pollutants that are prevalent in those environments.

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Abstract  

Total particulate matter (TPM) was passively collected inside two classrooms of each of five elementary schools in Lisbon, Portugal. TPM was collected in polycarbonate filters with a 47 mm diameter, placed inside of uncovered plastic petri dishes. The sampling period was from 19 May to 22 June 2009 (35 days exposure) and the collected TPM masses varied between 0.2 mg and 0.8 mg. The major elements were Ca, Fe, Na, K, and Zn at μg level, while others were at ng level. Pearson′s correlation coefficients above 0.75 (a high degree of correlation) were found between several elements. Soil-related, traffic soil re-suspension and anthropogenic emission sources could be identified. Blackboard chalk was also identified through Ca large presence. Some of the determined chemical elements are potential carcinogenic. Quality control of the results showed good agreement as confirmed by the application of u-score test.

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Abstract  

The elemental microdistributions of peripheral and central parts of the lichen Flavoparmelia caperata exposed to industrial pollution were analysed, in order to better understand the elements distribution patterns in relation to the lichen constitution, thereby increasing our knowledge on uptake and release mechanisms. Nuclear microscopy techniques were used to visualize elemental distributions in sample transepts and associate their concentrations to sample morphology. The distribution data of the elements studied suggests there is biological regulation of internal concentrations. Considering thallus parts, element-specific internal translocation should be taken into account as one more factor affecting lichen “memory length”.

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Abstract  

During the months of July and August 1993 a lichen collection campaign was held in Portugal where about 250 samples were collected and analysed by thick target TIPIXE and INAA. Results for 44 different elements were obtained and a data base was built and subjected to Monte Carlo Aided Target Transform Factor Analysis (MCATTFA), a method developed at IRI (Delft). 10×10 km2 coast and 50×50 km2 far from coast sampling grids were used for collection. In this work we will present the results which were obtained based on a reduced data set of 36 elements measured by INAA. The results for 22 elements obtained by TTPIXE were published elsewhere. In this work we will also present the conclusions considering all the 44 elements determined by both techniques.

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Abstract  

Lichens, sampled around Chernobyl in 1990 and in Slovenia in 1992, were analyzed for radionuclides and elements, including Cs. Data were processed by Monte Carlo aided Target Transformation Factor (MCTTFA). The resulting factors indicate environmental accumulation routes. 40K : K and 210Pb : Pb ratios tested the procedure, showing fully mixed 40K and K, while for 210Pb and Pb the expected variability in specific radioactivity was confirmed. 137Cs showed a large factor-specific variability in 137Cs : Cs ratios. For the 1990 data, MCTTFA singled-out 137Cs in a separate factor, suggesting that the overall behavior of 137Cs cannot be derived from that of Cs: source (route)-related specific radioactivity makes that all individual transport-components should be taken into account.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: A. Montero Alvarez, J. R. Estévez Alvarez, H. Iglesias Brito, O. Pérez Arriba, D. López Sánchez, and H. T. Wolterbeek

Summary  

An epiphytic lichen (Physcia alba sp.) grown over Roystonea regia tree was used as biomonitor of air quality in the Havana City west side. During the survey, 81 sampling sites were selected according to traffic and industry conditions. The concentration for 14 elements (Mg, Al, Ca, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Cd and Pb) was determined by flame atomic absorption spectrometry (FAAS) and anodic stripping voltammetry (ASV). Contents of Cu, Zn, Cd and Pb obtained by both techniques were compared. Several biological reference materials (RM's) were analyzed in order to assure the quality of analytical results. Some pollution sources were identified using principal component analysis. A total of 5 factors were achieved, of which 4 could be interpreted in terms of anthropogenic pollution sources. However, the expected correlation between traffic influence and lead concentration in lichen could not be demonstrated. The factor values patterns are presented.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: N. Canha, M. Freitas, M. Almeida-Silva, S. Almeida, H. Dung, I. Dionísio, J. Cardoso, C. Pio, A. Caseiro, T. Verburg, and H. Wolterbeek

Abstract  

One Plus Sequential Air Sampler—Partisol was placed in a small village (Foros de Arrão) in central Portugal to collect PM10 (particles with an aerodynamic diameter below 10 μm), during the winter period for 3 months (December 2009–March 2010). Particles masses were gravimetrically determined and the filters were analyzed by instrumental neutron activation analysis to assess their chemical composition. The water-soluble ion compositions of the collected particles were determined by Ion-exchange Chromatography. Principal component analysis was applied to the data set of chemical elements and soluble ions to assess the main sources of the air pollutants. The use of both analytical techniques provided information about elemental solubility, such as for potassium, which was important to differentiate sources.

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