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Dynamics of mercury in the environment

Mercury is a persistent, mobile and bio-accumulative element in the environment and retained in organisms. Because mercury is an element it is ultimately persistent; it cannot be converted to a non-mercury compound. Mercury in the aquatic environment is changed to various forms, mainly methylmercury. Once mercury enters into the environment, mercury permanently exists in the environment by changing its chemical forms depending on the environment. Figure as below shows the mercury species and transformations in the environment.

Mercury in the atmosphere is broadly divided into gas form and particulate form. Most of mercury in the general atmosphere is in gas form (95% or more). Gaseous mercury includes mercury vapor, inorganic compounds (chlorides and oxides), and alkyl mercury (primarily methylmercury).

Mercury pathway on site may be during flushing of mercury to the glass shell, Mercury is in liquid phase, under certain well-defined conditions, can cause liquid metal embrittlement (LME) of susceptible metallurgy or amalgam corrosion (AMC) The risk analysis procedures involves laboratory analysis of metallic equipment for timely prediction of mercury deposition. Pure mercury during flushing or Mercuric sulfide deposition from environment is possible on metallic surfaces, however the mechanisms by which mercury is absorbed by steel are not known conclusively but reaction with grain boundary elements or compounds is the most likely postulate. Simple cleaning and decontamination treatments often suffice for completely retrieve mercury on metallic equipment Removal of mercury from metal surfaces can be accomplished by surface treatments through sand ballasting or scrapping of surfaces, however workers are required to wear proper PPEs.

Mercury is contaminant stressor for potentially exposed receptors (human beings), as a polytechnic institute and labor residential colony are within one kilometer periphery; possible...
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