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Havelcova M.,Czech Institute of Rock Structure And Mechanics | Melegy A.,National Research Center of Egypt | Rapant S.,Geological Survey of the Slovak Republic
Chemosphere | Year: 2014

Polycyclic aromatic hydrocarbons (PAHs) were extracted from 30 samples (24 soils and 6 stream sediments) collected in El-Tabbin area in the southern part of Greater Cairo, Egypt. Isopleth maps of PAHs clarified the regional variability and identified the most affected regions in the area suffering from high pollution. The total PAH concentrations were 53.4-5558.0ngg-1 in the sample extracts. The highest values were found in a soil sample near a coke factory, with the highest concentration of single PAHs, which were 1064.8ngg-1 of fluoranthene and 1286.4ngg-1 of phenanthrene. The calculated ratios and indexes allowed to elucidate origin of the organic compounds and to identify emission sources. The overall molecular patterns are signatures of pyrolysis of fossil fuels and biomass. Petrogenic contamination was recognised in the sediment samples due to petroleum products deliveries from ships. Also perylene was prominent especially in samples of the River Nile sediments as a diagenetic product of fungi. Other detailed information on petrogenic sources was provided by analysis of alkanes and calculation of alkane ratios. © 2013 Elsevier Ltd. Source

Briestensky M.,Czech Institute of Rock Structure And Mechanics | Kostak B.,Czech Institute of Rock Structure And Mechanics | Stemberk J.,Czech Institute of Rock Structure And Mechanics | Petro L.,Geological Survey of the Slovak Republic | And 2 more authors.
Acta Geodynamica et Geomaterialia | Year: 2010

This paper examines the results of fault microdisplacement analyses obtained from sites located both at the surface and underground in western Slovakia. The results of surface monitoring showed significant annual climatic effects on the various displacement components. In contrast, the results of underground monitoring in caves showed minimal climatic effects. It is seen that the influence of climate decreases markedly with depth. The yearly peak-to-peak amplitude of climatic variations may be as high as 1 mm at the surface but only 0.1 mm underground. The amount of tectonic displacement can be determined once such climatic considerations have been taken into account. Our fault displacement measurements show horizontal strike-slip rates of tenths of mm or hundredths of mm per year. In addition, vertical displacements have been recorded at Prekážka Quarry, Driny Cave, and Slopy Cave. The network is sufficiently dense to identify changes in displacement activity recorded during recent, significant, earthquake events. Furthermore, three gauges have also helped to determine the local stress orientation in Driny Cave. Source

Melegy A.,National Research Center of Egypt | Slaninka I.,Geological Survey of the Slovak Republic | Paces T.,Czech Geological Survey | Rapant S.,Geological Survey of the Slovak Republic
Environmental Earth Sciences | Year: 2011

Inputs of As to a small catchment due to chemical weathering of bedrock, mechanical weathering of bedrock, and atmospheric precipitation were 71.53, 23.98 and 0.02 g ha-1 year-1, respectively. The output fluxes of As due to mechanical erosion of soil, biological uptake, stream discharge, and groundwater flow were 6.32, 4.77, 0.37 and 0.02 g ha-1 year-1, respectively. The results indicate that arsenic accumulates in soil and regolith with a very high rate. This is attributed to the selective weathering and erosion with respect to arsenic and fixation of arsenic in the secondary solids produced by weathering. The output fluxes of As in stream and groundwater in Vydrica catchment in Slovak Republic (0.39 g ha-1 year-1) based on muscovite-biotite granites and granodiorites were much lower compared to catchments in a gold district in the Czech Republic. These results may be ascribed to the low levels of arsenic pollution measured in Vydrica catchment. The arsenic fluxes were estimated by calculation of mechanical and chemical weathering rates of the bedrocks in Vydrica catchment from mass balance data on sodium and silica. The justification of the steady state of Na and Si is that neither of the elements is appreciably accumulated in plants and in exchangeable pool of ions in soil. © 2010 Springer-Verlag. Source

Melegy A.A.,National Research Center of Egypt | Cveckova V.,Geological Survey of the Slovak Republic | Krcmova K.,Geological Survey of the Slovak Republic | Rapant S.,Geological Survey of the Slovak Republic
Environmental Earth Sciences | Year: 2010

As much as 24 soil samples and 6 stream sediments from the River Nile were studied in El-Tabbin region (Great Cairo, Egypt). Twelve chemicals, potentially toxic elements posing potential environmental risk, were the object of concern in this study. Mean contents of analysed elements (in mg kg-1) in soils and the River Nile stream sediments were the following: Ass 3.6/Asss 1.5, Cds 0. 33/Cdss 0.12, Crs 87. 7/Crss 141.5, Cus 40.3/Cuss 43.8, Hgs 0.03/Hgss 0.13, Pbs 33.3/Pbss 20.2, Zns 150/Znss 109, Ses 0.24/Sess 0.05, Nis 37.2/Niss 48, Sbs 1.25/Sbss 1, Bas 892/Bass 431, Vs 103.3/Vss 167.8. Furthermore, geochemical background values were derived for soil and stream sediment samples. The values are as follows (in mg kg-1): Ass 1.33/Asss 1, Cds 0.48/Cdss 0.05, Crs 54.7/Crss 106.5, Cus 23.8/Cuss 23, Hgs 0.025/Hgss 0.095, Pbs 15.3/Pbss 13.5, Zns 70/Znss 55, Ses 0.13/Sess 0. 05, Nis 19.5/Niss 32.5, Sbs 1/Sbss 1, Bas 266/Bass 275, Vs 50.7/Vss 119. More than two-thirds of soil and sediment samples exceeded established (based on literature data) risk limit values for non-polluted environment. Based on environmental risk assessment for potentially toxic elements in soils and sediments in more than 45% of total area disturbed environment (IER = 1-3) was documented and more than 13% of territory was characterised with highly disturbed environment (IER > 3). © 2009 Springer-Verlag. Source

Rapant S.,Geological Survey of the Slovak Republic | Fajcikova K.,Geological Survey of the Slovak Republic | Khun M.,Comenius University | Cveckova V.,Geological Survey of the Slovak Republic
Environmental Earth Sciences | Year: 2011

Health risk, defined as possibility or probability of health damage, illness or death of humans due to exposure to risk factors in the environment, was derived for geological environment (soils) and estimated at national scale for the whole Europe and at more detailed regional scale for Slovak Republic. The assessment was based on data obtained from international geochemical mapping of Europe (Geochemical Atlas of the Europe-827 soil samples) and national geochemical mapping programme of the Slovak Republic (9,860 soil samples). The following chemical elements were evaluated: As, B, Ba, Be, Cd, Cu, F, Hg, Mn, Mo, Ni, Pb, Sb, Se and Zn. The health risk assessment method was based on calculations of average daily doses of individual elements analysed in every collected soil sample. Exposure levels were set by using exposure parameters and reference doses from integrated databases of US EPA. The results of calculations were transformed into various sorts of maps (dot, pixel) to delineate areas where increased contents of risk elements can pose risk to human health. The average levels of chronic and carcinogenic risk are presented in the form of tables for single European countries and administrative units of Slovak republic. The results of European mapping (Geochemical Atlas of Europe) indicate that increased levels of potentially toxic elements in soil (mainly As, Pb and Ni) occur primarily in the countries of southern and western Europe. Such elements are associated with increased health risk for resident population. For the countries of northern Europe health risk was estimated at significantly lower level. Relatively high sampling density in Slovak Republic made it possible to calculate health risk at more detailed scale for individual administrative units (municipalities, provinces). The increased health risk level was found in areas well known for high soil contamination (e. g. mining areas). © 2010 Springer-Verlag. Source

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