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- Author or Editor: M. Gallorini x
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Abstract
In Parkinson disease Fe and other metals increase in Substantia Nigra(SN) and other basal nuclei. Since Fe can generate citotoxic free radicals,Neuromelanin (NM) could play an important protective role in neurons. In thiswork an original procedure for separation of NM, preparation of samples andanalysis is presented. The determination of SN and its NM elemental contentwas carried out by instrumental neutron activation analysis. Several actionswere taken to reduce the metal contaminations: use of high purity reagents,dissection of tissues with titanium coated tools and adequate processing ofsamples.
Abstract
The evaluation of the eco-toxic consequences of heavy metals on the biosphere requires assessment of their biological effects. This involves the determination of the different ionic species and the various chemical forms of each element. For many elements, the usual electrochemical methods for the analysis of different chemical species do not meet the required sensitivity; ppm or even ppb concentration ranges represent often the actual content of many matrices. For many elements as Hg, V, Cr, As, and Se one of the most sensitive method of trace determinations down to the ppb level is the NAA. Unfortunately this method gives information only on the total number of nuclei present, regardless to their outer structure and chemical forms. In this work, some examples are given of the feasibility of NAA to the determination of trace amounts of different chemical species of some heavy metals, when coupled to specific separation procedures.
Abstract
A radiochemical separation procedure based on chromatographic separation using Chelex-100 in 0.1M HAc-0.1M NH4Ac at pH 4.8 and TDO in 6M HCl, has been developed to determine Cd, Co, Cr, Fe, Se, The, U, W and Zn in three biological materials of botanic origin used as SRM's: 1547 Peach Leaves, 1515 Apple Leaves and the new proposed material Spinach. The aim was to obtain more information for these elements whose values are not yet determined or are given only as 
suggested values
.
Abstract
Potentially toxic metals in the food chain that can lead to deleterious effects on human health have been well documented. Because of the toxicity of some metals, levels of 1 ppm or less must be routinely monitored in foods to ensure human safety. To ensure the accuracy of measurement, NBS in a cooperative interagency agreement with the Food and Drug Administration is involved in developing and certifying selected elements in food grain as a part of the Standard Reference Material program. Both instrumental and radiochemical neutron activation analysis were used to analyze two food grain standard reference materials (Rice and Wheat Flours) for trace element certification.
Abstract
The atmospheric particulate of industrialized cities had become a mixture of potentially toxic substances whose concentrations must be monitored to assess the pollution levels. Trace metals and elements are part of these pollutants and the knowledge of their total concentration in the air as well as their distribution in the different aerosol particle sizes is necessary to evaluate the pollution risk in terms of maximum present levels and long term exposure. In the present work, a preliminary part of a study initiated for monitoring the trace element levels present in the atmospheric particulate of the city of Milan (north Italy) and of its suburban areas is presented. More than 25 elements have been determined in Milan downtown along a period of three years and in different weather conditions. The granulometric distribution of selected potentially toxic elements (such as vanadium, lead, cadmium, nickel) has been also determined to evaluate their concentrations in different inhalable fractions (alveolar and bronchial — tracheal). Instrumental Neutron Activation Analysis (INAA) has been used for the determination of the great part of the elements while Graphite Furnace Atomic Absorption Spectroscopy (GF-AAS) has been employed for the determination of lead and, in some cases, for nickel, cadmium and copper.
Abstract
The concentration of more than 25 trace elements have been determined in total air particulate matter and in the size segregated fractions from the urban area of Pavia (North Italy). The PM10 fraction was also collected and analyzed. A study of the solubility in water and in physiological solution of the trace elements contained in the PM10 was also carried out. The resulting solutions were further submitted to column chromatography using Chelex 100 to perform a preliminary chemical characterization. INAA was used as the main analytical technique. ET-AAS was used for all Pb and Cd measurements and, in some cases, for the analysis of V, Mn, Cu and Ni.
Abstract
Twenty-two radiochemical separation procedures for neutron activation analysis (NAA) of environmental and biological samples are presented. They are currently applied in the context of trace metal research related to the protection of the environment and human health. The radiochemical procedures are related to the separations of the elements into groups which allow the determination of up to 50 elements in each sample or to specific separations for single elements. The experience gained in the application of these radiochemical separations over more than ten years allows us to consider them as reliable for sensitive determinations of trace metals in environmental and biological samples.
Abstract
Multielemental analysis of atmospheric particulates collected on filter paper has been investigated using different radioisotopic exciting sources. Quantitative determinations for zinc and lead during a one year period are reported.
Summary
Lichens as biomonitors and neutron activation analysis as analytical technique have been employed to evaluate the trace element atmospheric pollution in the metropolitan area of the city of Pavia (Northern Italy). Transplanted lichens (Parmelia sulcata and Usnea gr. hirta) and air particulate matter have been monthly collected and analyzed during the winter 2001-2002. INAA and ET-AAS have been used for the determination of 28 elements in air particulate matter and 25 elements in lichens. Trace metals concentrations as well as the corresponding enrichment factors were evaluated and compared.
Abstract
High specific activity radiotracers are very suitable for studies related to the toxicological impact of trace elements onto human health. In order to investigate the metabolic behaviour of Low Level Exposure (LLE) to trace elements, it is necessary to carry out in-vitro and in-vivo experiments with tracers whose concentration is of the same order of magnitude as the present environmental exposure values (ng-
g/kg day). Preparations, separations and purifications of some No Carrier Added (NCA) radiotracers (48V,95m,96Tc,195m,g,197m,gHg,199Au,202Tl) produced by either cyclotron or nuclear reactor irradiation, are presented and discussed. This work reviews the more recent advances in this field carried out by our groups.
