Authors:G. Capannesi, A. Cecchi, C. Ciavola, and A. Sedda
The present paper confirms that evergreen oak leaves (Ouercus ilex) are a reliable biological monitor for pollution originating from vehicular traffic. By treating of experimental data statistically a simple model was obtained which explains pollution levels in terms of vehicular density and particulate resuspension effects. An extensive list of current literature in this field is also included.
Evergreen oak was chosen as a possible biological monitor of environmental pollution. It was shown that there is a direct relationship between the concentration of elements in leaves and the presence of pollution sources, i.e. the density of vehicular traffic.
Thermal neutron activation analysis technique was used in air pollution and aerosol elemental content and size distribution
investigations. Air pollution samples were collected on Whatman 41 paper filters which were activated along with known quantities
of standards in a flux of ∼1013 n·cm−2·s−1. The activity of the samples was measured with a 40 cm3 Ge(Li) detector and analyzed with the computer program JANE, which identified the isotopes and found their quantities by
normalization with the standard measurement results. Correlation between the various elements, in particular those belonging
to dust from the desert and those considered typical urban air pollution, is investigated.
The potential of five species of trees as historical monitors of heavy metal air pollution has been investigated. The study was carried out at a site 2 km from an industrial complex including several metal refineries. Using neutron activation, heavy metal concentrations were measured in the xylem as a function of the year of wood formation. The manganese concentrations were by far the highest. In maple trees the high natural level of this essential trace element masked any increases due to pollution. In ash and cedar increased Mn concentrations were found, relative to control trees, but there is evidence for radial translocation. In hemlock the time variations of the average Mn concentrations followed the production rates of the refineries but large variations among individual trees were observed. Hemlock was estimated to accumulate up to 0.3% of the atmospheric Mn input.
The purpose of this study was to use instrumental neutron activation analysis (INAA) to investigate the effectiveness of oak tree leaves as indicators of atmospheric pollution. Leaves were sampled from several different cities in southwestern Ontario, Canada and tested for 16 different trace elements (U, Dy, Ba, Ti, Sr, I, Br, Mg, Cu, Na, V, K, Al, Mn, Cl and Ca). The results show promise for the use of oak leaves as multielemental environmental monitors due to their apparent ability to reflect the overall pollution levels of the vicinity in which they grow. Oak leaves were found to be superior to both birch and maple leaves for monitoring most of the elements studied.
Neutron activation analyses of wood shavings from tree rings have shown that plant tissues grown through periods of varying
environmental conditions keep permanent records of the trace elements they received through nutrients from their immediate
surroundings. Detailed examination of several species of trees, along with dendrochronological data, suggest the possibilities
of utilizing this technique for pollution monitoring as well as for developing valuable information for environmental modelling.
Botanical samples were used as monitors for zinc pollution resulting from vehicular traffic. Euphorbia terracina and Calotropis procera were the botanical monitors used in this work. Zinc concentrations were reported alongside a motorway stretch of 50 km. Variations
in concentration with respect to the perpendicular distance from the roadside were also reported. The effect of wind turbulence
and the wind direction on the concentrations is discussed. In addition, differences between open areas and confined areas
with respect to the elemental uptake were also discussed. INAA, using reactor neutrons, was employed for the determination
of Zn concentrations in the samples.
Nuclear and isotopic techniques are valuable tools in assessing the levels of environmental pollution by toxic elements and for studying how these contaminants affect human health. More than 90 counterparts from 55 countries around the world have participated in projects on these topics, supported by the International Atomic Energy Agency (IAEA), during last ten years. With the support of the IAEA, for example, an appropriate metrology for compositional characterization of size fractionated airborne particulate matter was developed, verified and implemented in more than 40 countries. This paper reviews the development and application of environmental metrology tools involving nuclear analytical and isotopic techniques, as seen from the particular perspective of IAEA programmes.
Authors:O. Baykara, H. Hasar, E. Öbek, and M. Doğru
This paper presents a case study of radioactive pollution of groundwater caused by leachate from an open landfill. Alpha- and beta-radioactivity analysis of the leachate from different points in the region and associated fountain water from a village down stream were carried out during four seasons. The alpha- and beta-radioactivity concentrations were under the detection limit in all samples and ranged between 0.07 and 2.17 Bq/l, respectively. The beta-radioactivity concentration from 129I, 137Cs and 90Sr individual radioisotopes were determined and their annual effective dose was calculated.
The International Atomic Energy Agency (IAEA) has been promoting studies on air pollution since 1992. During the period 1992–1999 there have been six major co-ordinated research and regional technical co-operation projects in which 77 counterparts from 40 Member States actively participated. The studies supported by the IAEA have included ambient and workplace airborne particulate matter, the use of appropriate plant biomonitors and a series of laboratory intercomparison exercises in support to these projects. Recent and current IAEA projects in this field are reviewed in the light of the application of neutron activation analysis, which has been used as a major analytical technique by more than two thirds of the counterparts, and contributed also approximately two thirds of all analytical results for the intercomparison exercises.