M. V. Frontasyeva

Mosses as biomonitors of atmospheric heavy metal deposition: Spatial patterns and temporal trends in Europe

In recent decades, mosses have been used successfully as biomonitors of atmospheric deposition of heavy metals. Since 1990, the European moss survey has been repeated at five-yearly intervals. Although spatial patterns were metal-specific, in 2005 the lowest concentrations of metals in mosses were generally found in Scandinavia, the Baltic States and northern parts of the UK; the highest concentrations were generally found in Belgium and south-eastern Europe. The recent decline in emission and subsequent deposition of heavy metals across Europe has resulted in a decrease in the heavy metal concentration in mosses for the majority of metals. Since 1990, the concentration in mosses has declined the most for arsenic, cadmium, iron, lead and vanadium (52-72%), followed by copper, nickel and zinc (20-30%), with no significant reduction being observed for mercury (12% since 1995) and chromium (2%). However, temporal trends were country-specific with sometimes increases being found.

Heavy metal contamination of topsoils around a lead and zinc smelter in the Republic of Macedonia.

The results of a first systematic study of spatial distribution of different elements in surface soil over the Veles region (50 km(2)) known for its lead and zinc industrial activity in the recent past are reported. A total of 201 soil samples were collected according to a dense net in urban area and less dense net in rural area. The total of 42 elements were analyzed by epithermal neutron activation analysis (ENAA) and by atomic absorption spectrometry (AAS). The content of elements such as As, Au, Cd, Cu, Hg, In, Pb, Sb, Se, Zn in soil samples around the lead and zinc smelter and in the adjacent part of the town of Veles has appeared to be much higher than in those collected in the surrounding areas due to the pollution from the plant. Thus, the content of Cd (three times); Pb and Zn (two times) is even higher than the corresponding intervention (critical) values according to the Dutch standards. The results obtained by two complementary analytical techniques, AAS and ENAA, are discussed in terms of multivariate statistics. GIS technology was applied to depict the areas most affected by contamination from the lead and zinc smelter.

Active moss biomonitoring of trace elements with Sphagnum girgensohnii moss bags in relation to atmospheric bulk deposition in Belgrade, Serbia

Active biomonitoring with wet and dry moss bags was used to examine trace element atmospheric deposition in the urban area of Belgrade. The element accumulation capability of Sphagnum girgensohnii Russow was tested in relation to atmospheric bulk deposition. Moss bags were mounted for five 3-month periods (July 2005-October 2006) at three representative urban sites. For the same period monthly bulk atmospheric deposition samples were collected. The concentrations of Al, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Cd, and Pb were determined by instrumental neutron activation analyses and atomic absorption spectrometry. Significant accumulation of most elements occurred in the exposed moss bags compared with the initial moss content. High correlations between the elements in moss and bulk deposits were found for V, Cu, As, and Ni. The enrichment factors of the elements for both types of monitor followed the same pattern at the corresponding sites.

Experimental substantiation of the possibility of developing selenium- and iodine-containing pharmaceuticals based on blue–green algae Spirulina platensis

The great potential of using blue-green algae Spirulina platensis as a matrix for the production of selenium- and iodine-containing pharmaceuticals is shown experimentally. 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) in S. platensis biomass were determined by means of epithermal neutron activation analysis. The dependence of selenium and iodine accumulation in spirulina biomass on a nutrient medium loading of the above elements was characterized. To demonstrate the possibilities of determining toxic element intake by spirulina biomass, mercury was selected. The technological parameters for production of iodinated treatment-and-prophylactic pills are developed.

Country-specific correlations across Europe between modelled atmospheric cadmium and lead deposition and concentrations in mosses

Previous analyses at the European scale have shown that cadmium and lead concentrations in mosses are primarily determined by the total deposition of these metals. Further analyses in the current study show that Spearman rank correlations between the concentration in mosses and the deposition modelled by the European Monitoring and Evaluation Programme (EMEP) are country and metal-specific. Significant positive correlations were found for about two thirds or more of the participating countries in 1990, 1995, 2000 and 2005 (except for Cd in 1990). Correlations were often not significant and sometimes negative in countries where mosses were only sampled in a relatively small number of EMEP grids. Correlations frequently improved when only data for EMEP grids with at least three moss sampling sites per grid were included. It was concluded that spatial patterns and temporal trends agree reasonably well between lead and cadmium concentrations in mosses and modelled atmospheric deposition.

Heavy metal and nitrogen concentrations in mosses are declining across Europe whilst some “hotspots” remain in 2010

In recent decades, naturally growing mosses have been used successfully as biomonitors of atmospheric deposition of heavy metals and nitrogen. Since 1990, the European moss survey has been repeated at five-yearly intervals. In 2010, the lowest concentrations of metals and nitrogen in mosses were generally found in northern Europe, whereas the highest concentrations were observed in (south-)eastern Europe for metals and the central belt for nitrogen. Averaged across Europe, since 1990, the median concentration in mosses has declined the most for lead (77%), followed by vanadium (55%), cadmium (51%), chromium (43%), zinc (34%), nickel (33%), iron (27%), arsenic (21%, since 1995), mercury (14%, since 1995) and copper (11%). Between 2005 and 2010, the decline ranged from 6% for copper to 36% for lead; for nitrogen the decline was 5%. Despite the Europe-wide decline, no changes or increases have been observed between 2005 and 2010 in some (regions of) countries.

Monitoring of trace element atmospheric deposition using dry and wet moss bags: accumulation capacity versus exposure time.

To clarify the peculiarities of trace element accumulation in moss bags technique (active biomonitoring), samples of the moss Sphagnum girgensohnii Rusow were exposed in bags with and without irrigation for 15 days up to 5 months consequently in the semi-urban area of Belgrade (Serbia) starting from July 2007. The accumulation capacity for 49 elements determined by ICP-MS in wet and dry moss bags was compared. The concentration of some elements, i.e. Al, V, Cr, Fe, Zn, As, Se, Sr, Pb, and Sm increased continuously with exposure time in both dry and wet moss bags, whereas concentration of Na, Cl, K, Mn, Rb, Cs, and Ta decreased. Irrigation of moss resulted in a higher accumulation capacity for most of the elements, especially for Cr, Zn, As, Se, Br, and Sr. Principal component analysis was performed on the datasets of element concentrations in wet and dry moss bags for source identification. Results of the factor analysis were similar but not identical in the two cases due to possible differences in element accumulation mechanisms.

Trends of atmospheric deposition of trace elements in Macedonia studied by the moss biomonitoring technique

In 2002 and 2005 the moss biomonitoring technique was applied to air pollution studies in the Republic of Macedonia in the framework of the International Cooperative Programme on Effects of Air Pollution on Natural Vegetation and Crops under the auspices of the United Nations Economic Commission for Europe (UNECE-ICP Vegetation) Convention on Long-Range Transboundary Air Pollution (LRTAP). In August 2005 samples of the terrestrial mosses Homolothecium lutescens and Hypnum cupressiforme were collected at 72 sites evenly distributed over the territory of the country, in accordance with the sampling strategy of the European moss survey programme. A total of 41 elements (Na, Mg, Al, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Zr, Mo, Cd, Sb, I, Cs, Ba, La, Ce, Sm, Eu, Tb, Dy Hf, Ta, W, Hg, Pb, Th, and U) were determined by instrumental epithermal neutron activation analysis and atomic absorption spectrometry. Principal component analysis was used to identify and characterize different pollution sources. Distributional maps were prepared to point out the regions most affected by pollution and to relate this to known sources of contamination. A few areas, as in 2002, are experiencing particular environmental stress: Veles, Skopje, Tetovo, Radoviš and Kavadarci-Negotino, whereas the agricultural regions in the south, south-west, and south-east show median European values for most elements of mainly pollution origin. A significant increase in the content of Ni is noticed in the 2005 moss survey compared with 2002, due to the increased production of the ferro-nickel smelter in Kavadarci. A higher content of Cd, Hg, and Pb in 2005 relative to 2002 can be explained by pollution from the lead-zinc smelter in Veles, as well as the pollution that comes from the open slag waste dump of this smelter. Protection activities on the dump of slag from the former ferrochromium smelter located near Tetovo resulted in a lower content of Cr in the 2005 moss survey.

TRACE ELEMENT CONTAMINATION IN INDUSTRIAL REGIONS OF POLAND STUDIED BY MOSS MONITORING

The use of terrestrial mosses as biomonitors in large-scalemulti-element studies of heavy metal deposition from theatmosphere is a well established technique in Europe. Insuch studies it is advantageous to determine as many elements as possible in order to distinguish betweendifferent source categories. A combination of INAA and AAShas been found very useful in this respect, in particularwhen epithermal activation is used for instrumental neutronactivation analysis. A total of 33 elements (Al, Cl, Sc, V,Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Ag, Cd, Sb,I, Cs, Ba, La, Ce, Tb, Yb, Hf, Ta, W, Au, Pb, Th, and U) inPleurozium schreberi (Brid.) Mitt. moss samples fromthe Silesia-Kraków Industrial Region and Legnica-GłogówCopper Basin and from the control (background) area inNortheast Poland were identified. The highest concentrationsof the majority of trace elements were found in mossesgrowing in the Silesia-Kraków Industrial Region, only Cu andAs concentrations were higher in mosses in the Legnica-Głogów Copper Basin. These results are in conformity withthe load of trace elements emissions in these areas.

Atmospheric deposition of heavy metals in northern Serbia and Bosnia-Herzegovina studied by the moss biomonitoring, neutron activation analysis and GIS technology

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.