ACTIVE MOSS BIOMONITORING TECHNIQUE FOR ATMOSPHERIC DEPOSITION OF HEAVY METALS IN ELBASAN CITY, ALBANIA

The effects of industrial activities associated with ferrochromium metallurgy and cement production of Elbasan urban area, Albania, were investigated by using the moss-bag technique. Samples of Hypnum cupressifornie were collected from a remote unpolluted area (Llogora, N: 40 degrees 12' 31.1 ''; E: 19 degrees 35' 6.7 '') in south-west part of Albania. Metal concentrations in the pre-exposed bags were measured (i.e. background levels). Metal levels determined from moss bags at 14 sites of Elbasan city were exposed for 6 months (September 2011-March 2012) without irrigation. Heavy metals (Cu, Pb, Cd, Zn, Cr, Mn, Ni, Co and Fe) were determined by AAS technique, using flame and/or electrothermal system. CVAAS was used for Hg as well as ABS technique for K and Na determination. For a better interpretation of data, elements, such as K, Na, Ca and Mg, were also included. Concentrations of trace levels of heavy metals (Cu, Pb, Zn, Ni, Co, Cd, Hg), especially in the sites close to the pollution sources, were elevated during the period of exposure. However, examination of the biological state of the exposed mosses indicated that contamination existed near to the pollution sources, with elevated concentrations of Pb, Zn, Mn, Co and Hg. Some cities result to be highly polluted with Mn, Pb, Zn and Hg, emitted from cement industry and metallurgy operation on this area, as well as moderately polluted, due to the vehicular emissions and city dust. Therefore, we have tried to categorize different places of the city on the basis of the metal concentrations in the mosses and data statistical treatment. The comparison of the results with unexposed moss samples allowed us assessing the enrichments factors in exposed moss samples for all determined elements. Correlation analysis was carried out in order to distinguish different geochemical mobility of the elements.