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Abstract  

The content of the trace elements As, Br, Co, Cr, Fe, Hg, Sb and Zn has been evaluated in hair samples from selected population groups within Malaysia. Each population group was formed of individuals selected to be representative of the adult population living in a well-defined community. The groups were chosen from distinct regions with different socio-economical living habits in order to detect variability of the trace element burden among Malaysian. All the measurements were performed by means of instrumental neutron activation analysis after the hair samples were carefully washed according to standard procedures. The results for all elements investigated do not differ significantly from reported values for other regions of the world. The levels of As, Hg, and Sb are significantly different for the various groups and is strongly linked to local environmental factors.

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Abstract  

Three hundred ancient Turkish potsherds were analyzed by instrumental neutron activation analysis, and the resulting data analyzed by several techniques of multivariate statistical analysis, some only recently developed. The programs AGCLUS, MASLOC, and SIMCA were sequentially employed to characterize and group the samples by type of pottery and by site of excavation or collection. Comparison of the statistical analyses by each method provided archaeological insight into the site/type relationships of the samples and ultimately evidence relevant to commercial relations between the ancient communities and to specialization of pottery production over time. The techniques used for statistical analysis were found to be of significant potential utility in the future analysis of other archaeometric data sets.

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The regulatory system in force in Italy concerning radioisotopes is based on two statutes dating back to 1962 and 1964; the latter is based on a 1962 Directive of European Community, of which Italy is a Member. European Directives of 1980, 1984, 1989, 1990 and 1992 will be enacted into Italian legislation by January 1st, 1996. In the statutes in force the basic rules are established governing the holding and use of, trading in and disposal of radioactive material. These activities are subject to notification and licensing. Notification and licensing are based on two tiered system: a local, regional or provincial level and a national one, depending on the intersection of a number of parameters. The role of the governmental organs, state agencies such as ANPA (National Agency for Environmental Protection), local administrative bodies, their competence and their powers are discussed with regard to notification and licensing.

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Abstract  

The continued erection of nuclear installations which is expected in the future involves a greater production of long-lived fission products, which result in a concentration increase in the biosphere, the hydrosphere and the atmosphere. In the frame of a broad survey program, a routine method has been developed with the help of the European Communities to investigate the129I content of thyroid glands of cows. It is the purpose of this project to determine the present concentration situation of this nuclide, which in the Federal Republic of Germany mainly concerns the North German low plains. Between autumn '76 and summer '77 18 cows have been investigated with respect to129I, and thyroid glands have been taken at different times in November '76 and August '77. Without exception, the animals were 13-month old bulls, part of which has pastured, while the other part has been fed. The detection limit of the method is 20fCi of129I.

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Abstract  

Some trace elements exist in cosmetics due to the mineral origin of their raw materials and there is no information about their concentration levels in these products. Other trace elements must not be contained in cosmetics according to the list of European Communities. Instrumental neutron activation analysis has been applied to determine the elements: cerium, cesium, europium, hafnium, lanthanum, lutetium, potassium, rubidium, samarium, scandium, sodium, tantalum, terbium, tungsten and ytterbium in eyeshadow, face powder and rouge make up cosmetic products from the Greek market. According to our results, a wide range of values was found between the three examined cosmetics as well as between the different samples belong to the same kind of cosmetics. This probably could be attributed to the various manufacturers of the analyzed samples. Moreover the use of neutron activation analysis as a suitable routine method is discussed for the control of some elements which must not be contained in cosmetics.

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Abstract  

The method of proton particle-induced X-ray emission (proton PIXE) has been employed to study the trace element composition of human fingernails. The samples were colleted from 51 subjects randomly selected from a working community of about 500 adults and they were analyzed by the thick-target external beam technique of the PIXE method. The samples were exposed to the proton beam as 1-mm thick pellets and irradiated with 2 MeV protons having 20 nA beam intensity. For 40 C irradiations, the concentration of fourteen elements, K, Ca, Ti, Mn, Fe, Ni, Cu, Zn, As, Se, Br, Rb, Sr and Pb, were measured by comparison with a calibration obtained from the NBS orchard leaf standard (SRM 1571). Some anomalous cases have been revealed from this study and they are attributed to environmental factors. The frequency distributions of the elements are presented and the results compared with available data.

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Abstract  

Radioactivity has been known for more than a hundred years. Nuclear data compilations through nuclide charts began in the 1920s with the work of Soddy, and were later rationalized in the Karlsruher Nuklidkarte. For 50 years, it has depicted the status of our nuclear knowledge in an easy reading form. It was born as an educational and scientific tool that gives access to the basic bricks that the nuclear Physics community needs to build the physics knowledge at the femtometer (10−15 m) level. Nuclide data is a bridge between research and development. On the one hand, the nucleus can be regarded as a vast laboratory with, the possibility to test from fundamental concepts of the Standard Model to the genesis of the elements in the Universe. On the other hand, this data is also leading to applications in many areas of everyday life such as health care or environmental monitoring.

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Abstract  

The k 0-IAEA program developed for implementation of the single comparator instrumental neutron activation analysis method (k 0-INAA) has been used for elemental analysis with NIRR-1 irradiation and counting facilities. The existing experimental protocols for routine analysis based on the relative method were used to test the capability and reliability of the program for the analyses of geological and biological samples. The Synthetic Multi-element Standards (SMELS) types I, II and III recommended by the international k 0 user community for the validation of k 0-NAA method in NAA laboratories, furthermore, the following standard reference materials: NIST-1633b (Coal Fly Ash) and IAEA-336 (Lichen) were analyzed. Results obtained with the version 3.12 of the k 0-IAEA program were found to be in good agreement with the data obtained with the established relative method using WINSPAN-2004 software. Detection limits for elemental analysis of geological and biological samples with NIRR-1 facilities are provided.

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Summary  

A Radioanalytical Emergency Procedures Manual Database (REPMD) will be an important tool to assist laboratories preparing for emergency response to a sudden release of radioactivity into the environment. The collection and systematic organization of existing sampling, screening and radioanalytical methods will enable laboratories to assess the appropriate methodologies for their use. REPMD is intended to be flexible, searchable, and interactive to accommodate a wide range of available techniques while being protected from unauthorized modifications. Website access by the world-wide scientific community will make the database a foundation for international comparison. The information in the database will also serve as a comprehensive and periodically updated source of methods and procedures suitable for training programs and rapid reference.

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Summary  

The phytoremediation potential of native trees in a U and Th contaminated wetland was examined. Based on measurements of the annual biomass of leaves and their contaminant concentrations, we estimated the reduction in soil contamination over time. Significant differences among tree species were found, with tupelo (Nyssa sylvatica) and sweetgum (Liquidambar styraciflua) having a significantly greater capacity to remove U and Th from the soil than the other tree species. More U was phytoextracted than Th from the site. Phytoextraction rate constants were developed and revealed that although U and Th phytoextraction was exceptionally high at the site, an order of magnitude greater than predicted, the community of native trees would lower the soil inventory of 238U and 232 Th by only 1& over the next 100 years.

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