Reactive gaseous mercury

Lindberg SE, Stratton WJ. 1998. Atmospheric mercury speciation concentrations and behavior of reactive gaseous mercury in ambient air. Environ Sci Technol 32 49-57. 

Stratton WJ, Lindberg SE, Perry C J. 2001. Atmospheric mercury speciation critical evaluation of a mist chamber method for measuring reactive gaseous mercury. Environ Sci Technol 35 170-177. 

Atmospheric deposition is an important source of mercury for surface waters and terrestrial environments that can be categorized into two different types, wet and dry depositions. Wet deposition during rainfall is the primary mechanism by which mercury is transported from the atmosphere to surface waters and land. Whereas the predominant form of Hg in the atmosphere is Hg° (>95%), is oxidized in the upper atmosphere to water-soluble ionic mercury, which is returned to the earth s surface in rainwater. In addition to wet deposition of Hg in precipitation, there can also be dry deposition of Hg°, particulate (HgP), and reactive gaseous mercury (RGM) to watersheds [9-11]. In fact, about 90% of the total Hg input to the aquatic environment is recycled to the atmosphere and less than 10% reaches the sediments [12]. By current consensus, it is generally accepted that sulfate-reducing bacteria (SRB)... 

Landis MS, Keeler GJ, Al-Wali KI, Stevens RK (2004) Divalent inorganic reactive gaseous mercury emissions from a mercury cell chlor-alkali plant and its impact on near-field atmospheric dry deposition. Atmos Environ 38 613-622... 

Development and characterization of an annular denuder methodology for the measurement of divalent inorganic reactive gaseous mercury in ambient air. Environ. Sci. Technol. 36(13), 3000-3009. 

Sheu G.-R. and Mason R. P. (2001) An examination of methods for the measurements of reactive gaseous mercury in the atmosphere. Environ. Set Technol. 35, 1209-1216. 

Main mercury species in ambient air are elemental mercury (Hg°), reactive gaseous mercury (Hg(II)), mercury bound to aerosols, and methylmercury. Though dimethyl-mercury is together with Hg° the most volatile form of Hg, it has not been detected unequivocally in the atmosphere. Elemental mercury represents >95% of Hg in the atmosphere with ambient concentrations at the order of 1-5 ng m whereas MeHg in air was found to be in the range of 1 to 20 pg m (Pirrone et al. 2001). For this reason, in most cases mercury is pre-con-centrated on solid absorbers (gold, silver, activated carbon traps, etc.) prior to analysis (Drabaeck and Iverfeldt 1992, Horvat 1996). 

Mercury speciation varies in atmospheric, aquatic, and terrestrial enviromnents. In the atmosphere, mercury is in the form of gaseous elemental Hg (95%), Hg + (called reactive gaseous mercury), and trace amounts of methylmercury. Particulate and reactive mercury in the atmosphere travels short distances, usually less than 50 km, and has a residence... 

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