EVOLUTION OF MERCURY CONTAMINATION IN BRAZIL

This papa reviews the history of Hg contamination in Brazil by charact erizing and quantifying two major sources of Hg emissions to the envir onment: industrial sources and gold mining. Industry was responsible f or nearly 100% of total Hg emissions from the late 1940's to the early 1970's when efficient control policies were enforced leading to a dec rease in emissions. Gold mining, on the other hand was nearly insignif icant as a Hg sauce up to the late 1970's but is presently responsible for over 80% of total emissions. Presently, over 210 t of Hg are rele ased into the environment in Brazil annually. Nearly 170 t cane from g old mining operations 17 t come from chlor-alkali industry and 10 t co me from all other industrial user Emissions to the atmosphere are the major pathway of Hg releases to the environment and reach over 160 t.y r(-1) with approximately 136 t.yr(-1) from gold mining.