ATMOSPHERIC MERCURY AND TRACE-ELEMENTS IN THE REGION OF ALTA FLORESTAIN THE AMAZON BASIN

In the early 1980's the Amazon region in the North of Brazil was the s cene of the most intense gold rush in the history of Brazil. Metallic mercury (Hg) in gold mining activities is used to amalgamate particula te gold. The other sources of Hg emissions in Amazonian are tailing de posits and biomass burning of tropical forests and savannas. Total Hg concentrations in the urban area of Alta Floresta ranged from 20 to 58 00 ng/m(3). Indoor total Hg concentration in gold shops ranged from 25 0 to 40600 ng/m(3). Particulate Hg accounts for 5 to 20% of total Hg i n Alta Floresta. Through Factor and cluster analysis it was obtained a pattern of relationships between total Hg, fine and coarse mode parti culate Hg, Pt, Pb, Ag and several other trace elements associated with the amalgamation process. A clear correlation was also observed with the fine mode biomass burning aerosol and coarse mode soil dust.