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Abstract  

Gent air samplers were used for air particulate matter sampling in Sado estuary area, separating fine and coarse fractions. Three sampling sites were chosen (Palmela, Faralhão and Tróia), inside a 15 km × 25 km area at Setúba region, 50 km south of Lisbon, Portugal. Transplants of Parmelia sulcata Taylor were suspended in nylon bags within the same area following a 2.5 km × 2.5 km grid, during the same period as the aerosol collection. Both lichen transplants and filters were analysed by k 0-INAA. This work compares MCTTFA results given by the two air pollution monitoring procedures. The main differences concern a physiological factor in biomonitors and a better definition of traffic and re-suspension by aerosols.

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Abstract  

A project has been undertaken to carry out a long term study on atmospheric air pollution in Chile using biomonitors. Samples of different species of lichens were collected in clean areas (native forest), analyzed and transplanted to the Santiago Metropolitan Area. In addition, samples of Tillandsia recurvata were collected in the Metropolitan Area for comparison purposes. The preparation of the samples was done under controlled, cryogenic conditions and analyzed by neutron activation analysis and solid sampling atomic absorption spectrometry. As part of the routine QA/QC procedures, the analytical laboratories, have participated in intercomparison runs organized by the IAEA for the determination of trace and minor elements in two lichens samples. The present paper describes the activities carried out within the framework of this project.

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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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Journal of Radioanalytical and Nuclear Chemistry
Authors: A. Senhou, A. Chouak, R. Cherkaoui, Z. Moutia, M. Lferde, A. Elyahyaoui, T. El Khoukhi, M. Bounakhla, K. Embarche, A. Gaudry, S. Ayrault, and M. Moskura

Abstract  

In this work, we compare the concentrations of trace elements for fourty samples of lichens, mosses and tree barks used as biomonitors in an air pollution biomonitoring study in Morocco. This comparison concerns six types of biomonitors: the lichens Xanthoria parietina, Parmelia sulcata and Evernia prunastri; the moss Hylocomium splendens and barks of cedar and cork oak. The complementarity of three analytical methods was used in order to increase the number of determined elements. These techniques are: 14 MeV neutron activation analysis, thermal neutron activation analysis using the k 0-quasi-absolute method and X-ray fluorescence analysis. The results enabled us to compare the element accumulation sensitivity for the six biomonitors used and to study the local concentration variations versus biomonitors sizes and the height above ground of their collecting point.

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Abstract  

Numerous studies have demonstrated that the human toenail is a reliable biomonitor for the intake of Se and other elements. The objective of this study was to evaluate the use of the toenail as a biomonitor for Mn. Toenail specimens from One Source multivitamin users and matched controls were selected. Se was measured using established NAA methods, then Mn was measured via a new procedure. The Se results confirmed the accurate classification of the cohort. However, the nail did not show significant, positive response to Mn supplementation. We hypothesize that the persistence of exogenous Mn confounded the results.

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Abstract  

The olive tree (Olea europaea) is an icon of southern Europe and awidespread evergreen in mainland Portugal. First results of a continuing studyon the ability of olive-tree bark to act as an air-pollution biomonitor arepresented and discussed here. Other than lower signals and an anticipatedsystemic control over some elements, there seems to be no a priori reasonfor ruling out the possibility of using bark in atmospheric trace-elementsurveys. In fact, nonparametric statistics show that, despite their relativemagnitude, the variation patterns of bark and lichen concentrations significantlyfollow one another all across the study area.

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Abstract  

Epiphytic bromeliads have been used as biomonitors of air pollution since they have specialized structures in leaves for absorbing humidity and nutrients available in the atmosphere. Leaves of five bromeliad species were collected in the conservation unit Parque Estadual Ilha do Cardoso, São Paulo State, Brazil, and analyzed by INAA. Vriesea carinata was the species showing most accumulation, with the highest mass fractions of K, Na, Rb and Zn. Similar results were previously found for the same species collected in the dense ombrophilous forest. Chemical composition of bromeliads provided an indication of the atmosphere status in the conservation unit.

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Abstract  

The toenail was examined as a biological monitor of Mg, Zn, and Cu intake using an observational case control model. The One Source Cohort matched 63 individuals in Columbia Missouri who took the One Source multivitamin with 63 control individuals. The matching criteria were based on age, sex, ethnicity, smoking status, and body mass index. The multivitamin contained supra-nutritional levels of Se, Mg, Cu, and Zn. The toenail clippings were examined for these elements using instrumental neutron activation analysis (INAA). A statistical analysis did not indicate a significant difference for Mg, Cu, or Zn between the nails of One Source supplement users and control subjects (p<0.76, 0.55, and 0.85, respectively). The trace nutrient Se was used as an internal control. Previous studies have consistently demonstrated that toenail Se is positively correlated with Se supplement use and the analysis did result in a significant correlation in the toenails of One Source users and control subjects (p<1·10−4). This internal Se control suggests that the One Source Cohort is largely free from misclassification errors that could interfere with the biomonitor response for the supranutritional intake of Mg, Cu, and Zn.

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Abstract  

In 1999 investigation, the needles of Sabina chinesis L. from 11 hot spot tourist cities extending over China were collected as biomonitors for evaluation of atmospheric elemental differences in those cities. Thirty five elements were determined by instrumental neutron activation analysis (INAA). The experimental data reflected the environmental alteration in the cities that have different geographical position, population burden and industrialized level. Eventually by using the data processed by factor analysis (FA) and subsequent cluster analysis (CA), the cities were grouped into six sorts of the urban atmospheric deposition with corresponding elements.

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Abstract  

This study deals with the influence of the exposure conditions on biological uptake, by looking into concentrations of Ni and V in lichen thalli and tree bark after continuous and discontinuous field trials at littoral sites impacted by anthropogenic emissions. Biomonitors were assessed by k 0-INAA and AAS. Correlations at Sines are more apparent than at Viana or Lisboa. When data from all sites are pooled, V shows correlations for practically every situation while Ni shows none, which may indicate a dissimilar uptake mechanism for each element. At Sines, V/Ni ratios reach values that comply with emissions from oil-related industries.

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