Marcello M. Veiga; John A. Meech
University of British Columbia, Dept. Mining and Mineral Process Engineering
6350 Stores Rd., Vancouver, V6T 1Z4
Des Tromans University of British Columbia, Dept. Metals and Materials Engineering
Abstract
Mercury pollution in the Amazon region represents today one of the most serious environmental issues faced by mankind. Quantities from 70 to 170 tonnes of mercury are discharged into the Amazonian environment annually from gold infomal mining operations. Vegetation fire is pointed as another major source of Hg emission. Mercury is likely emitted in a reactive form form vegetation and the extent of the biota contamination is wider than the Hg emitted by mining activities. Stability of metallic mercury in aquatic environments is investigated. In contact with organic-rich sediments, mercury-organic complex formation is favourable as indicated by thermodynamic and laboratory studies. Although methylation process from dissolved complexes is an unclear issue, mercury mobility as complexes might increase bioavailability.