Spatial and Temporal Distribution of Dust-Bound Trace Metal Elements around Kuhdasht Watershed Area in Iran

Dust, as a source of trace metal elements, affects the health of society. The spatial and temporal concentrations of dust-bound trace metals (Cd, Pb, Ni, Zn, Cu, and Mn) in Kuhdasht watershed (456 km(2)), Lorestan Province, Iran, is investigated. Dust is collected using glass traps placed in ten research stations in the region. The spatial and temporal distribution of dust trace metals are plotted using ARC-GIS. The highest and the lowest concentrations of Zn (9751150 mg kg(-1)), Pb (46.352.9 mg kg(-1)), and Cd (2.443.30 mg kg(-1)) are obtained in winter, of Ni (98110 mg kg(-1)) and Cu in autumn (16.053.5 mg kg(-1)), and of Mn in summer (385505 mg kg(-1)). The spatial concentrations of dust-bound trace metals indicate all, except Cu, show a decreasing trend from the mountains toward the plains, similar to that of soil and of dust, except for Zn, which shows higher concentrations in dust than in soil. The potential sources of dust-bound trace metals and their rate of contamination are also investigated using the enrichment and contamination factors. The major sources of Cd and Zn in the dust of watershed are due to anthropogenic activities or from activities outside the borders.