Mercury mobility

Valega, M., A.I. Lillebp, I. Caqador, M.E. Pereira, A.C. Duarte, and M.A Pardal. 2008. Mercury mobility in a salt marsh colonised by Halimione portulacoides. Chemosphere 73 1224—1229. 

Eckley, C. S. and B. Branfireun. 2008. Mercury mobilization in urban stormwater runoff. Sci. Total Environ. 403(1-3) 164—177. 

The most common toxic metals in industrial use are cadmium, chromium, lead, silver, and mercury less commonly used are arsenic, selenium (both metalloids), and barium. Cadmium, a metal commonly used in alloys and myriads of other industrial uses, is fairly mobile in the environment and is responsible for many maladies including renal failure and a degenerative bone disease called "ITA ITA" disease. Chromium, most often found in plating wastes, is also environmentally mobile and is most toxic in the Cr valence state. Lead has been historically used as a component of an antiknock compound in gasoline and, along with chromium (as lead chromate), in paint and pigments. 

There are several environmentally significant mercury species. In the lithosphere, mercury is present primarily in the +II oxidation state as the very insoluble mineral cirmabar (HgS), as a minor constituent in other sulfide ores, bound to the surfaces of other minerals such as oxides, or bound to organic matter. In soil, biological reduction apparently is primarily responsible for the formation of mercury metal, which can then be volatilized. Metallic mercury is also thought to be the primary form emitted in high-temperature industrial processes. The insolubility of cinnabar probably limits the direct mobilization of mercury where this mineral occurs, but oxidation of the sulfide in oxygenated water can allow mercury to become available and participate in other reactions, including bacterial transformations. 

Mercury provides an excellent example of the importance of metal speciation in understanding biogeochemical cycling and the impact of human activities on these cycles. Mercury exists in solid, aqueous, and gaseous phases, and is transported among reservoirs in all these forms. It undergoes precipitation-dissolution, volatilization, complexation, sorption, and biological reactions, all of which alter its mobility and its effect on exposed populations. The effect of all... 

Hintelmann H, St. Louis V, Scott K, Rudd J, Lindberg SE, Krabbenhoft D, Kelly C, Heyes A, Harris R, Hurley J. 2002. Reactivity and mobility of newly deposited mercury in a Boreal catchment. Environ Sci Technol 36 5034-5040. 

Mierle G, Ingram R. 1991. The role of humic substances in the mobilization of mercury from watersheds. Water Air Soil Pollut 56 349-357. 

The release of mercury into the environment, its introduction in the biogeochemical cycle, and its concentrated propagation along the food chain due to changes in climate are a worldwide concern. The problem of mercury in the society is not new, it has long been considered as toxic element of concern owing to its mobility,... 

Therefore, after due consultation with the experts in the field and review of available C R systems, it is proposed to tackle the end-of-life FLs in two ways (1) deploy safe, fixed, and mobile lamp crushing systems to capture the mercury and reduce the waste volumes before transportation and (2) feed the crushed material and other components into a suitable recycling and recovery system to assure safe management. The review of available technologies has brought out two types of technologies that could be used in the proposed C R system ... 

The high mobility and tendency to dispersion exhibited by mercury, and the ease with which it forms alloys (amalgams) with many laboratory and electrical contact metals, can cause severe corrosion problems in laboratories. A filter-cyclone trap is described to contain completely mercury ejected accidentally by overpressuring of mercury manometers and similar items. 

Colwell, R.R., G.S. Sayler, J.D. Nelson, Jr., and A. Justice. 1976. Microbial mobilization of mercury in the aquatic environment. Pages 437-487 in J. 0. Nriagu (ed.). Environmental Biogeochemistry, Vol. 2. Metals Transfer and Ecological Mass Balances. Ann Arbor Sci. Publ., Ann Arbor, MI. 

With respect to Cr a distinction should be made between Cr(III), which is the common oxidation state in the soils, being rather immobile and so toxic, and Cr(VI), which is very mobile and very toxic. With respect to Hg, the situation is even more complex, due to the occurrence of mercuric mercury (Hg2+), mercurous mercury (Hg2+), elemental mercury (Hg°) and organic mercury species, such as methyl mercury, (CH3)2Hg (see Section 18.5). Furthermore, volatilization of elemental mercury and organic mercury species is common. A description of these... 

Driscoll et al. (1994) have studied the mercury species relationships among water, sediments, and fish (yellow perch) in a series of Adirondack lakes in New York state, USA. In most lakes, approximately 10% of the total mercury loading was in the form of C2HsHg+. Mercury concentrations increased as pH fell, but the best correlation was found between [dissolved Al] and [dissolved Hg] suggesting that the same factors are responsible for mobilizing both these metals. Methylmercury concentrations correlated strongly with the dissolved organic carbon content in the water. Fish muscle tissue was analyzed for mercury and showed an increase with age. However, the study was unable to resolve the question of whether the principal source of mercury to these lakes was atmospheric deposition or dissolution from bedrock due to acid rains. 

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