Mercury (Hg) is a highly volatile metal, and as a result, a global pollutant. In fact, the number of fish and wildlife Hg advisories in Canada and the U.S. has been steadily increasing. It is generally thought that emissions of Hg from human activities such as coal burning have led to the increase in advisories. Many recent studies have demonstrated the importance of Hg exchange between the atmosphere and biosphere, and have shown that this exchange is more dynamic than previously hypothesized. Delivery of Hg to most water bodies and terrestrial environments, even in remote Boreal and Arctic ecoregions, is largely by atmospheric deposition. Inorganic Hg(II) dominates this atmospheric deposition, and is then methylated to monomethyl Hg (MMHg; the organic, toxic form of Hg) in anaerobic environments such as lake sediments and wetlands. MMHg then bioaccumulates through food webs. In addition, inorganic Hg(II) and MMHg is transformed photochemically and possibly biologically to elemental Hg(0) and lost to the atmosphere. This “re-emission” of Hg to the atmosphere influences the residence time of Hg in aquatic and terrestrial pools, and hence the amount of Hg subsequently available for methylation. The University of Alberta Low-level Mercury (Hg)
has been established as a premier Hg analytical facility both within Canada and internationally. This facility is devoted to leading edge research into the biogeochemistry of Hg, and providing a dynamic environment for the training of highly qualified personnel. Our facility is now equipped to measure all aspects of Hg emissions, deposition and biogeochemical cycling at environmentally relevant concentrations.
Last Modified: 2007-02-08