Fifty five samples were analysed for 10 trace elements by INAA. In the absence of identified samples of known origin, similarities
between the samples were established by constructing a minimal spanning tree based on 5 selected elements. Thereafter grouping
was tested using concentration, sum of concentration, and normalised concentration indices. From the results, tentative patterns
of population movement can be deduced.
Authors:L. Kovacs, C. Zamboni, L. Oliveira, V. Salvador, I. Sato, and M. Azevedo
The concentrations of Cl, K and Na were analyzed in human body fluids (whole blood and serum) using NAA, resulting in the
first biochemical baseline values for the Brazilian population. These data permitted us a discussion about the advantages
and limitations of using this analytical technique for clinical chemistry.
Authors:Sun Laiyan, Lu Fengying, Su Rongwei, and Zhen Houxi
The concentrations of trace elements As, Br, Cd, Cr, Cu, Hg, Pb, Sb, Se and Zn in Chinese foodstuffs were determined by instrumental or radiochemical neutron activation analysis or atomic absorption spectrometric methods. 1198 samples including 20–25 kinds of main foodstuffs were analyzed. The results are given and the daily intake of the trace elements for population groups concerned have been calculated.
The occurrence of anomalous enhancements of U-isotope activities in the surrounding environment of a phosphate fertilizer factory complex at the southwest of Spain has been established. It seems that significant amounts of U, released by such industries, are being accumulated in the environment, which may substantially contribute to the collective radiation dose received by the local population.
The number of chromosomal and chromatid breaks, deletions, as well as fragments, have been followed in correlation to the physical dose as assessed by the specific radioactivity of DNA. Human lymphocytes from adult donors were incubated for 44 hours in media supplemented with tritiated thymidine. An uneven distribution of labelling in the cell population has been found and about 50% of the population of cells remained unlabelled. The dose-response curve was flat reflecting loss of damaged cells and/or repair of damage. The dose-response curve showed that at the experimental conditions used the dose of 100 mGy absorbed from incorporated tritium caused about 0.1 deletions per. cell. Doubling the number of deletions to about 0.2 per cell required approximately a five times higher absorbed dose.
Sixteen minor and trace element contents of diet samples collected from the Pratas islanders were determined using instrumental neutron activation analysis. Samples were prepared by the duplicate portion technique, collecting during a 3-day period in winter. Dry weight elemental concentrations and daily dietary intake by islanders are compared with those taken by urban population living in Taiwan, resulting in higher intake of most elements. In addition, concentration of natural radionuclides and artificial fallout in daily diet were determined by means of -spectroscopy; the annual intake of radioactivity was evaluated and compared with those in population of neighboring Taiwan and South China. Features of the elemental concentration and radioactive concentration in the diet are discussed.
Authors:A. Khuder, M. Bakir, J. Karjou, and M. Sawan
XRF and TXRF were established as useful techniques for multi-element analysis of whole blood and human head hair samples.
Direct-XRF with different collimation units and different X-ray excitation modes was successfully used for the determination
of S, P, K, Ca, Fe, and Br elements in blood samples and K, Ca, Mn, Fe elements in human hair samples. Direct analysis by
TXRF was used for the determination of Rb and Sr in digested blood and human hair samples, respectively, while, the co-precipitation
method using APDC for TXRF analysis was used for the determination of Ni, Cu, Zn, and Pb elements in both matrices. As a result,
the improved XRF and TXRF methods were applied for multi-element determination of elements in whole blood and human hair samples
in non-occupational exposed population living in Damascus city. The mean concentrations of analyzed elements in both matrices
were on the reported range values for non-occupational population in other countries.
Calculation of meaningful minimum detectable concentrations (MDCs) and decision levels (DLs) requires proper evaluation of all uncertainties and biases of the measurement process as determined by appropriate blanks. Using a population of method blank results to estimate
blank is appropriate for calculation of MDCs since MDC is an a priori concept and not intended to be sample specific. Using a population of method blanks for calculation of sample specific decision levels (DLs) requires estimation of
blank from net counts or count-rate so that sample specific efficiency, recovery, decay correction, and other factors can be used. However, data has shown that DLs calculated as 1.65
sample are easier to implement and compare favorably with DLs calculated as the tblank when a total propagated uncertainty (TPU) is reported by the laboratory and used to estimate
sample instead of just the counting uncertainty. DLs calculated in either of these ways resulted in no more than 5% false positives.
In this paper, the physical and chemical methods used in our laboratory for the measurement of99Tc in natural samples are reviewed. Levels of99Tc in rainwater, algae, and freshwater samples are given. In addition, and estimation of the radiological impact of99Tc to the population, derived from our earliear atmospheric99Tc measurements, is presented. For rainwater, levels of137Cs are also given for comparison.
Authors:S. Liu, C. Chung, J. Chuang, C. Wang, and N. Aras
Sixteen minor and trace element contents of diet samples from three different social population groups in Taiwan were determined. Samples were prepared using duplicate portion technique by collecting the 15 subjects ate and drank during a 3-day period. Samples were homogenized, freeze-dried, and elemental concentration of minor and trace elements were determined by instrumental neutron activation analysis. Elemental concentrations and daily dietary intake of the elements were compared with those in the other nations, and possible origins were discussed.