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Abstract  

Domestic radioactivity has been studied by using LR-115 and CR-39 solid state nuclear track detectors (SNTD) and a suitable beta- and gamma-gaseous counter. A new calibration method, based on measuring thoron (220Rn) to radon (222Rn) ratios, has been developed for determining the -activity originating from radon in different Marrakechi dwellings. The influence of building materials as well as pollution and airing factors, on domestic radioactivity has been investigated.

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Abstract  

Mercury pollution in the industrial environment of Chile has been studied using hair as a monitor. Data from samples representing people living in the non-polluted and also from the polluted areas show that, hair is an effective and convenient indicator of environmental mercury pollution in Chile. A major source of mercury pollution and its transport is contaminated water. Hair is found to concentrate mercury from water to an extent of 80 to 500 fold increase in hair concentration. This absorption occurs in a contact time of 24 h and thus provides a means of treating mercury containing water to reduce the mercury to acceptable levels. The capacity of hair for this purpose is about 0.2% which means that, with a kilogram of hair /valued at less than 25 cents/ nearly 20.000 litres of contaminated water /at 0.1 ppm mercury/ can be treated. This is an inexpensive and convenient alternative to conventional ion-exchange processes which are generally very expensive, particularly for developing countries.

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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  

For the first time the moss biomonitoring technique has been applied to air pollution monitoring in Central Russia (Tula region). INAA at the IBR-2 reactor has made it possible to determine the content of 33 elements in mosses collected at 83 sampling site. In addition to NAA, flame AAS (atomic absorption spectrometry) was applied to determine the content of Cd, Cu and Pb. Factor analysis was applied to determine possible sources of trace element deposition in Tula mosses. The geographical distribution of factor scores and some element distribution maps over the investigated territory are presented.

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Summary  

The study was performed in an urban area to identify the main pollution sources. Dry and living bog moss samples were exposed in parallel, and their accumulative capability as biomonitoring tools was compared. The procedures of moss exposure, preparation, and element concentration measurement performance are recommended. Chemical composition of moss material was determined using instrumental neutron activation analysis in a research reactor located in Delft, the Netherlands. The element concentration levels were lower in living moss than in dry one. Chemometric methods were suggested to identify specific element profiles attributing to factors impacting moss composition in various urban locations.

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The paper analyzed the changes of beetle assemblages in the litter layer of eutrophic pine forests in the zone polluted by a nitrogen fertilizer plant Joint Stock Company “Achema” (Lithuania). We hypothesized that abundance, diversity and life traits of beetle assemblages depend on the distance from the pollution source. The samples of the litter layer were taken from pine stands at the distances of 3, 5, 10 and 20 km from the plant. The PCA and GLM analyses were used to reduce the number of variables to the main environmental gradient and assess the influence of environmental factors on beetle abundance, number of species, and life traits. The dependence of species number, abundance and the presence of forest and dendrophagous species on the distance from the plant was detected. A significant impact of organic carbon content, nitrogen emission and moss cover on other life traits of beetles was disclosed. The abundance of moss fraction in the litter layer was positively correlated with increasing distance from the plant. The ability to tolerate polluted sites by three species: Atheta fungi, Micrambe abietis and Brassicogethes aeneus, and intolerance of pollution by eight species: Bryaxis puncticollis, Quedius limbatus, Cyphon pubescens, Cephenium majus, Cyphon padi, Cyphon variabilis, Gabrius appendiculatus and Philonthus cognatus, were detected by IndVal analysis. The distribution of litter species was affected by the distance from the plant and by the richness of moss cover.

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Résumé  

On attend généralement beaucoup de l'analyse par activation neutronique pour apporter des données sur les traces de métaux rencontrées dans les milieux atmosphériques pollués. Ces données devraient conduire à un projet de contrôle effectif de la pollution. On discute 5 articles de Colloque en tant qu'exemples de la nature des recherches sur la pollution de l'air, sur l'amĺioration des techniques analytiques pour aller au devant des besoins relatifs aux applications à l'environnement et sur la comparaison de techniques associées. L'expérience de l'auteur de l'article et de ses collaborateurs est alors prise comme exemple des différentes applications qui peuvent être faites de l'analyse par activation pour l'étude de traces métalliques dans la matière spéciale qu'est l'air urbain. Ceux qui pratiquent l'analyse par activation sont amenés à porter leur attention sur l'étude à grande échelle des problèmes de l'environnement et à ne pas réduire leurs efforts aux seuls aspects analytiques.

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Abstract  

Trace elements in airborne particulate matter collected monthly at suburban and rural areas in Korea were analyzed by instrumental neutron activation analysis (INAA). Neutron irradiation of the samples was done at the irradiation hole (neutron flux 1·1013 n·cm–2·s–1) of the TRIGA Mark-III Research Reactor in the Korea Atomic Energy Research Institute. For the verification of the analytical technique, two reference materials, NIST SRM-1648 and NIES CRM-8, were chosen for analysis. The accuracy and precision of the determinations of the 40 elements were compared with the reference values. We used this method (1) to analyze 30 trace elements in airborne particulate matter collected monthly with the high volume air sampler (PM-10) at two different locations and (2) to confirm the possibility of using this method as a routine monitoring tool to find out environmental pollution sources.

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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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Journal of Radioanalytical and Nuclear Chemistry
Authors: A. Senhou, A. Chouak, R. Cherkaoui, M. Lferde, A. Elyahyaoui, T. El Khoukhi, M. Bounakhla, K. Embarche, X. Bertho, A. Gaudry, S. Ayrault, and D. Piccot

Abstract  

In this paper the performances and the limitations of three multi-elementary analysis techniques are compared applied to a study of air pollution biomonitoring in Morocco. These techniques are: (1) 14 MeV neutron activation analysis (14 MeV-NAA), (2) thermal neutron activation analysis using the k 0 quasi-absolute method (k 0-NAA) and (3) energy dispersive X-ray fluorescence analysis (ED-XRF). The experimental procedures and the control of the analytical results using certified reference materials are described and discussed. The three methods were confronted for the analysis of lichens, mosses and tree-barks. The complementarity of these methods enabled us to determine 43 elements in different samples. The most suitable method for each element was selected according to the sensitivity and selectivity necessitating the minimum corrections of the matrix effects and/or the interfering reactions.

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