Moss biomonitoring of air pollution with heavy metals in the vicinity of a ferronickel smelter plant

The purpose of this study was to establish the atmospheric deposition of various elements in the Kavadarci region, Republic of Macedonia (known for its ferronickel mining and metallurgical activities) using moss biomonitoring, and to determine whether the deposition is anthropogenic or from geogenic influences. The sampling network includes 31 moss samples evenly distributed over a territory of about 600 km(2). A total of 46 elements (Ag, Al, As, Au, Ba, Be, Ca, Cd, Ce, Co, Cr, Cs, Cu, Dy, Er, Eu, Fe, Ga, Gd, Ge, Hg, Ho, K, La, Li, Lu, Mg, Mn, Mo, Na, Nb, Ni, P, Pb, Rb, Sb, Sm, Sr, Tb, Th, Ti, U, V, Yb, Zn, Zr) were determined by mass spectrometry with inductively coupled plasma (ICP-MS). Based on a distribution pattern of elements determined in moss, two anthropogenic geochemical associations (Co-Cr-Cu-Fe-Mg-Ni and As-Cd-Cu-Hg-Pb-Zn), were detected. The distribution of these elements shows an increased content (especially Ni, Co and Cr) in the moss samples from the surroundings of the smelter plant compared to the rest of the samples. Thus, the median value of Ni in moss samples from the whole region (40 mg kg(-1)) is much higher than the median for Macedonia (5.82 mg kg(-1)). Moreover, the median content of Ni in the moss samples from the polluted area (around the smelter) is 178 mg kg(-1) with an enrichment ratio in the moss samples of almost 5.5 times higher than the unpolluted areas (32 mg kg(-1)). This fact confirms the influence of the dust from the ferronickel plant to the air pollution in this region.