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Biomedical subjects

I Obrusník

Publications and source records attributed to I Obrusník.

8 recordsLinked to original sources

Environmental specimen banking in the Czech Republic: a pilot study.

In recognition of the importance of environmental specimen banking (ESB) as an important component of the described ongoing real-time environmental and health-related monitoring programmes, a proposal for a planned ESB pilot study in the Czech Republic is presented. Selection of biomonitors, analytes, sampling techniques and sites is discussed, especially with regard to the possible harmonization with ESB already operational abroad. Availability of validated analytical techniques for determination of up to 30 elements using nuclear and spectroscopic techniques, including speciation of several metals, and of the most important organic pollutants employing various chromatographic techniques in biological and environmental samples is demonstrated.

Air Pollutants↗

Analysis of membrane filters and thick fly ash samples by PIXE.

The possibility of the routine PIXE measurement of environmental samples has been tested at the INP in Rez. Both thin samples of aerosols collected on membrane filters Synpor and Nuclepore and thick aerosols and fly ashes samples pressed into pellets were analyzed. The Nuclepore filter was found more suitable for PIXE analysis of aerosols than the Synpor, and the thin aerosol sample analysis was found to be easier than the thick sample analysis. The grain size effect in the case of thick fly ash samples is discussed.

Air Pollutants, Occupational↗

A PC-based computer program for quality assessment of INAA results of emission and air particulate samples.

A PC-based computer program for quality assessment (QAS) of results obtained by neutron activation analysis (NAA) is described. Program QAS is designed for the quality assurance system based on a routine use of certified reference materials (CRMs) with similar matrix composition as the samples analyzed together with each sample batch. The results obtained for CRMs samples are then compared with certified (true) values and with the results obtained for particular CRM in previous analysis runs. Five various tests are applied to check the quality of NAA results (for CRM and, consequently, for real samples) obtained for a particular analysis run. Control charts for elemental concentrations found in CRM and ranges of results for duplicate aliquots of CRM are displayed to visualize possible discrepancies. The program accepts files transported from gamma-ray spectrometric system ND 683 (based on a PDP 11 computer), extracts and stores reference material results, and prepares a work spreadsheet for each set of results to avoid typist and other kinds of errors.

Air Pollution↗

Activation analysis of human hair as a tool for environmental pollution monitoring.

Recent development and uses of neutron activation techniques for human hair analyses are reviewed. The method of neutron activation analysis (NAA) appears to have the potential to be used as a tool for environmental pollution monitoring. Principally, two types of NAA procedure are in use nowadays for multielement analyses of human scalp hair. The more common of these is the method of instrumental neutron activation analysis (INAA), consisting of a single short-term (3-10 hours) exposure of hair to a beam of neutrons in a nuclear reactor, followed by two measurements of gamma-ray spectra at 2-3 days and 3-4 weeks after the end of irradiation. The following microelements can be commonly determined by this type of activation procedure: As, Au, Br, Cu, K, La, Na, Sb, Sm, Co, Cr, Cs, Fe, Hg, Rb, Sc, Se and Zn. The other of the two procedures involves the use of radiochemical separation techniques and is employed for quantitative determinations of elements that are not easily determined by INAA (Mo, Cd, Ni, etc.), or in cases where there is a need to achieve the lowest possible limits of analytical determination. The accuracy of NAA techniques is strongly dependent on the hair sampling and hair sample processing methods used. The analytical error of this method may vary within the range of 5-15%. Its applicability as a tool for monitoring the environmental pollution level is here demonstrated on an example of groups of individuals living in the areas differing by the degree of environmental pollution. The use of other biopsy materials, such as e.g. mammalian hair, for the purpose of environmental exposure monitoring is also considered in this review.

Activation Analysis↗

The hair of the common hare (Lepus europaeus Pall.) and of the common vole (Microtus arvalis Pall.) as indicator of the environmental pollution.

We made the INAA of hair of the common hare (Lepus europaeus Pall.) and of the common vole (Microtus arvalis Pall.) living in the emission zones. Both the hare and the vole are almost exclusively herbivores; they consume relatively large amounts of contaminated food and mirror reliably the contamination degree of the respective ecosystem. The use of free-living animals for the control of the environmental quality may complete effectively the information obtained by examination of habitants. Though the free-living animals lead a rather different way of existence it has been found that the analyses of their hair correlate very well with the analyses of human hair. It may be expected that the changes of concentrations of heavy metals will manifest themselves earlier in animals than in men, because the animals are strictly tied to the local food sources. The hair samples of hares contained increased concentrations of Sm, La, Au, As, Se, Cr, Sc, Fe, Ce, Th and Co. The hair of voles showed increased concentrations of Sm, La, Zn, As, Se, Cr, Sc, Fe, Sb, Ce, Cs and Co. A conspicuous trend towards the cumulation in hair was observed in the following elements: As, Se, Sc and Fe. The increase of their concentrations in the hair of animals from the emission regions amounted as such as to 10(3)%.

Animals↗