Mercury emissions to the atmosphere from natural gas burning in Brazil

MERCURY EMISSIONS TO THE ATMOSPHERE FROM NATURAL GAS BURNING IN BRAZIL. Increasing natural gas use in Brazil triggered a discussion of its role as a Hg source. We show that Hg emissions to the atmosphere from fossil fuel combustion for power generation in Brazil contribute with 6.2% (4.2 t yr(-1)) to the total anthropogenic Hg atmospheric emissions, with coal combustion and biomass burning as major sources. Natural gas contributes with 0.04 t yr(-1), mostly from electricity generation (88%) and industrial uses (7.6%). Preliminary results on Hg concentrations in natural gas suggest that a large fraction of it is trapped during refining and transport, which may create Hg point sources between extraction and consumption.