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- Author or Editor: M. Frontasyeva x
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Abstract
The effect of the production of phosphorus fertilizers on the pollution of the environment by rare-earth elements is reviewed. The main sources of rare-earth element pollution in the environment are described. The levels of REEs in components of the environment — atmosphere, snow, different types of soil, native and agricultural types of vegetation — that provide evidence for their participation in the biological cycle of plants are considered. The high values of the correlation coefficients lead one to think that the REE distribution in vegetation occurs under specific laws true for this family of elements.
Abstract
An intercomparison of data obtained for a moss reference material (Hylocomium splendens) used as biomonitor of atmospheric deposition by different multi-element techniques is presented. In total 43 elements (Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Zr, Ag, Sn, Sb, I, Cs, Ba, La, Ce, Nd, Sm, Eu, Gd, Tb, Tm, Yb, Lu, Hf, Ta, W, Au, Th, U) were determined using inductively coupled plasma-mass spectrometry (ICP-MS), conventional instrumental neutron activation analysis (INAA), epithermal neutron activation analysis (ENAA) and as well as shorttime neutron activation analysis without and with a6LiD-converter. Advantages and drawbacks of each method are discussed. The introduction of moss reference materials for atmospheric multi-element deposition studies involving nuclear analytical techniques is strongly recommended.
Abstract
The heavy metal pollution in the South Ural region was studied by nuclear and related techniques. The feasibility of the moss technique to study the regional air pollution is also presented.
Abstract
Samples of the mosses Hylocomium splendens and Pleurozium schreberi, collected in the summer of 1998, were used to study the atmospheric deposition of heavy metals and other toxic elements in the Chelyabinsk Region situated in the South Urals, one of the most heavily polluted industrial areas of the Russian Federation. Samples of natural soils were collected simultaneously with moss at the same 30 sites in order to investigate surface accumulation of heavy metals and to examine the correlation of elements in moss and soil samples in order to separate contributions from atmospheric deposition and from soil minerals. A total of 38 elements (Na, Mg, Al, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, As, Se, Rb, Sr, Zr, Mo, Sb, Cs, Ba, La, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Yb, Hf, Ta, W, Au, Th, U) in soil and 33 elements Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni, Zn, As, Se, Br, Rb, Ag, Sb, Cs, Ba, La, Ce, Sm, Tb, Yb, Hf, Ta, W, Au, Th, U) were determined by epithermal neutron activation analysis. The elements Cu, Cd and Pb (in moss samples only) were obtained by atomic absorption spectrometry. VARIMAX rotated principal component analysis was used to identify and characterize different pollution sources and to point out the most polluted areas.
Abstract
The results on atmospheric deposition of heavy metals and other trace elements using the moss biomonitoring technique in the northern part of Serbia and some areas of Bosnia-Herzegovina are presented. Samples of Hypnum cupressiforme along with some other moss types were collected at 92 sites during the summer of 2000. A total of 44 elements were determined by INAA using epithermal neutrons. High values of Cl and V content in the moss samples at certain areas are suspected to be associated with fires in oil refineries damaged during the 1999 NATO military action.
Abstract
A comparative study performed by means of both epithermal neutron activation analysis (ENAA) and prompt gamma neutron activation analysis (PGAA) concerning the distribution of 9 elements (Na, Al, Cl, K, Ca, Ti, Mn Fe and Sm) in unconsolidated sediments collected from the Black Sea anoxic region is presented. Principal component analysis (PCA) was used as a supplementary method in interpreting experimental data. The final results have shown that eight of them (Na, Al, Cl, K, Ti, Mn, Fe and Sm) have concentrations which differ by less than 30% from the corresponding concentrations of Upper Continental Crust (UCC), confirming the continental origin of sediments. At the same time, Ca concentration was about six times higher than that of UCC, this significant enrichment being due to the presence of the neighbouring oxygenated zone of considerable deposits of shell debris, characteristic of the Western Black Sea Continental Platform. Excepting Na and Mn, the concentrations of all other elements involved in this intercomparison were coincident within one standard deviation which attests the accuracy of this test. At the same time, PCA revealed the presence of five clusters, which could be put into concordance with the mineralogical composition of sediments, each of them consisting in equal proportions of elements determined by both methods.
Abstract
The mosses Pleurozium schreberi, Pseudoscleropodium purumandRhytidiadelphus squarrosus were used as biomonitors to study the atmospheric deposition of metals around the lead and copper-zinc smelters in Baia Mare. Samples representing the last three years" growth of moss or its green part, collected on the ground at 28 sites located 2-17 km from the source area, were analyzed by instrumental neutron activation analysis using epithermal neutrons (ENAA) and by flame atomic absorption spectrometry (FAAS). A total of 31 elements were determined, including most of the heavy metals characteristic of emissions from this kind of industry. The observed data for Pb, As, Cu, and Cd are all high compared with those observed in other regions of Europe with similar industries, but the concentrations in moss approach regional background levels at a distance of about 8 km from the main source area. Factor analysis of the data distinguishes two industrial components, one characterized by Pb, Cu, As, and Sb, and another one by Zn and Cd. A strong crustal component including five major elements (Na, Mg, Al, Ti, Fe) and an additional number of trace elements (Sc, V, Cr, Cs, Ba, REE, Th) also appears to be derived mainly from industrial sources. The mean I value in the present material is 5 times lower than the corresponding level in moss in Norway, and also consistently lower than elsewhere in Europe, a fact which evidences the endemic character of the examined area due to iodine depletion.
Abstract
To evaluate the potentiality of the blue-green algae Spirulina platensis as a matrix for the production of Se-containing pharmaceuticals, the background levels of 31 major, minor and trace elements (Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni using (n,p) reaction), As, Br, Zn, Rb, Mo, Ag, Sb, I, Ba, Sm, Tb, Tm, Hf, Ta, W, Au, Hg, Th were determined in Spirulina platensis biomass by means of epithermal neutron activation analysis. The possibility of the purpose-oriented incorporation of Se into Spirulina platensis biomass was demonstrated. The polynomial dependence of the Se accumulation on nutritional medium loading was revealed. The analytical technique used allows to control the amount of toxic elements in algae Spirulina platensis. Based on this study, a conclusion of the possibility to use Spirulina platensisas a matrix for the production of Se-containing pharmaceutical was drawn.
Abstract
This is the first systematic study of air pollution from heavy metals and other trace elements throughout several industrialized areas and national parks of Eastern Romanian Carpathians using the moss biomonitoring technique. Samples ofHylocomium splendens collected at 120 sites were analyzed by epithermal neutron activation analysis at the pulsed fast reactor IBR-2 at JINR, Dubna, for a wide range of elements including heavy metals and rare earths (Na, Mg, Al, Cl,K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni (by (n,p) reaction), Cu, Zn, As, Se, Br, Rb, Sr, Zr, Mo, Ag, Sn, Sb, I, Cs, Ba, La, Ce, Nd, Sm, Eu, Gd, Tb, Yb, Hf, Ta, W, Au, Th, and U). Copper, lead and cadmium were determined by AAS. Certified Reference Standards of mosses produced for interlaboratory comparisons in the European moss-survey 1995 were used to ensure the quality of the measurements. To present results in the form of coloured contour maps the geographical information system GIS-INTEGRO was used. The regional extent of pollution with specific metals was determined. Results reported are well consistent with those obtained in numerous recent projects carried out in Germany, the Netherlands, Poland, Bulgaria and other countries.
Abstract
Epithermal neutron activation analysis (ENAA) was used for study the biomass of Spirulina platensis. The background levels of concentration 27 macro-, micro- and trace elements ranging from 10-3 to 104 ppm was determined. It was found that the biomass of Spirulina does not contain toxic element concentrations above the tolerance level and can be utilized as a matrix of pharmaceuticals. The con
entrations of basic elements in C-phycocianin and DNA extracted from Spirulina platensis were determined by ENAA. A comparison of the element content of a whole Spirulina biomass with that of a refined C-phycocianin preparation was made.
