ASSESSMENT OF TRACE ELEMENTS BIOAVAILABILITY – INGESTION OF TOXIC ELEMENTS FROM THE ATTIC DUST COLLECTED FROM THE VICINITY OF THE FERRO-NICKEL SMELTER PLANT

The purpose of this study was to establish total and bioavailable contents of chemical elements in attic dust and their distribution in the area of the town of Kavadarci, Republic of Macedonia, and in this way to evaluate the exposure of population to toxic metals in areas with high industrial influences from the ferronickel smelter plant. The attic dust is derived predominantly from external sources such as aerosol deposits and soil dusting, and less from household activities. From that reason attic dust could be accepted as a tracer of historical aerosol pollution. All attic dust samples were analyzed for total and bioavailable element contents and their distribution in studied area. Several extraction agents recognized as representative for elements bioavailability assessment were applied to attic dust samples under investigations – phosphate buffer solutions that simulate human blood, for the simulation of lung inhalation carbonate buffer was used and 0.1 mol l –1 HCl solution to simulate stomach ingestion. A total of 18 elements (Ag, Al, As, B, Ba, Ca, Cd, Co, Cr, Cu, Fe K, Mg, Mn, Ni, Pb, Sr and Zn) were determined by atomic emission spectrometry with inductively coupled plasma (AES-ICP). The obtained results showed relatively high proportion of toxic elements bioavailability in the attic dusts samples from sites close to the metallurgical activities (Cr, Cu, Mn, Ni, Pb and Zn), most probably due to the small size and high reactivity of the particles of attic dust. As might be expected the highest leachable amounts of toxic elements were found for Ni, Co, Cr and Pb from attic dust in the extraction solution of HCl (0.1 mol l –1 HCl) compared with the other 3 extraction media. Discussion on trace elements mobility and bioavailability related to environmental pollution and effects on human health are presented.