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Abstract  

A significant dose contribution on the population could be derived from coal slags used as isolation material. Extremely high natural activities are measured in the coal slag, derived from the region of the settlement Ajka, Hungary. In some buildings monitored, the elevated -doses were nearly 5–10 times higher than the world average ones. The annual average indoor radon concentrations from the slag exceeded 400 Bq/m3 and in some cases up to 1200 Bq/m3. Due to the elevated exposure and the radon concentrations in the dwellings the annual dose was estimated to 8–24 mSv/y more than 5–10 times of the world average one.

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Abstract  

Phosphoric acid is generally obtained from an aqueous process starting with the reaction between phosphate rock and sulphuric acid. Due to their chemical similarity, uranium is usually associated with phosphate rock which during chemical processing is partitioned to phosphoric acid. Uranium determination in this matrix is a very important task because of its ingestion it could lead to radiological impact on the population. Therefore, a procedure was developed using an initial precipitation with calcium hydroxide and evaporation, followed by instrumental neutron activation analysis (INAA). The procedure was applied to analyse fourteen uranium enriched phosphoric acid samples.

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Abstract  

The intake of some “newer” trace elements via the daily diet by Iranian population groups was determined. The total mixed diets were prepared on the basis of dietary recording. Aluminium and nickel have been measured via atomic absorption spectrometry, vanadium and tin via radiochemical neutron activation analysis, and scandium via instrumental neutron activation analysis. The results for the Iranian diets are discussed and compared with corresponding data from other countries. The project has been performed in the frame of a co-ordinated research project of the International Atomic Energy Agency with participants from various countries.

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Abstract  

The intake of aluminum, arsenic, cadmium, lead and mercury via the daily diet by Iranian population groups was determined. The relevant daily diets were prepared through dietary recording and duplicate portion, and the trace elements were measured using analytical methods based on NAA, ICP and AAS. The results for the Iranian diets are discussed and compared with corresponding ones from other countries. The project has been performed in the frame of a co-ordinated research project of the International Atomic Energy Agency with participants from various countries.

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Abstract  

We have collected sixteen total diet samples from two socioeconomic groups in Turkey by duplicate portion techniques. Samples were homogenized with titanium-blade homogenizer, freeze dried and analyzed for their minor and trace elements mostly by neutron activation analysis. Bread and flour samples were also collected from the same regions and analyzed similarly by instrumental neutron activation analysis. We have determined concentrations of more than 25 elements in total diets, bread and flour, and fiber and phytate in total diets. We have determined daily dietary intakes of these population groups, probable source of elements through correlation coefficients, and enrichment factor calculations.

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Abstract  

In this study, blood serum trace elements, biochemical and hematological parameters were obtained to assess the health status of an elderly population residing in São Paulo city, SP, Brazil. Results obtained showed that more than 93% of the studied individuals presented most of the serum trace element concentrations and of the hematological and biochemical data within the reference values used in clinical laboratories. However, the percentage of elderly presenting recommended low density lipoprotein (LDL) cholesterol concentrations was low (70%). The study indicated positive correlation between the concentrations of Zn and LDL-cholesterol (p < 0.06).

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Abstract  

This study aims to investigate whether known carcinogenic chemical elements in atmospheric deposition might be associated with child mortality due to leukemia in the Portuguese population. A Bayesian hierarchical model was used to explore the association between lichen biomonitoring measurements of four elements—As, Hg, Ni, Pb—and childhood leukemia death counts taken at small administrative units. This geographical epidemiological study found a non-significant positive association between the risk of childhood leukemia and levels of arsenic, mercury and lead, and a non-significant negative association between the disease and the level of nickel. Lead seems to show a weaker association with childhood leukemia than arsenic and mercury.

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Abstract  

Over the last decades the acceleration of the industrialization and urbanization processes together with the intensive agricultural practices have resulted in an impact on the Piracicaba river basin, state of São Paulo, Brazil. The source rivers drain from an area of low population density, absence of heavy industries, non-significant agriculture, native forest and reforestation, the opposite is found in the middle part of the basin. Samples of riverbed sediments were collected along the basin for chemical analysis. Results showed that the source rivers still preserve their natural characteristics, while the Atibaia river in the middle part shows signs of pollution from the agricultural activity, industrial effluents and urban sewage.

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Abstract  

In 1999 investigation, the needles of Sabina chinesis L. from 11 hot spot tourist cities extending over China were collected as biomonitors for evaluation of atmospheric elemental differences in those cities. Thirty five elements were determined by instrumental neutron activation analysis (INAA). The experimental data reflected the environmental alteration in the cities that have different geographical position, population burden and industrialized level. Eventually by using the data processed by factor analysis (FA) and subsequent cluster analysis (CA), the cities were grouped into six sorts of the urban atmospheric deposition with corresponding elements.

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Abstract  

Periodically increasing and decreasing enthusiasm has accompanied the studies of medical significance of human hair elemental composition for at least two decades. In this field, nuclear analytical methods play an extremely important role, especially the instrumental neutron activation analysis (INAA). This paper tries to add some new knowledge to this problem. Two approaches are used — comparison of individual hair composition with certain diagnoses in clinic groups and comparison of population data with medical statistics. Rather large samples and multielement mathematical procedures helped reveal strong correlations valuable for diagnostic and health screening.

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