Inorganic mercury compounds water

Mercrobes mercury reduction technology (Mercrobes) is a proprietary, ex situ technology for the treatment of soils, sludges, sediments, and waters contaminated with mercury and mercury compounds. The process uses proprietary microbes to reduce organic and inorganic mercury compounds to elemental mercury. The vendor claims that in addition to reducing charged... 

Nervous System. The nervous system is also a common target of toxic metals particularly, organic metal compounds (see Chapter 16). For example, methylmercury, because it is lipid soluble, readily crosses the blood-brain barrier and enters the nervous system. By contrast, inorganic mercury compounds, which are more water soluble, are less likely to enter the nervous system and are primarily nephrotoxicants. Likewise organic lead compounds are mainly neurotoxicants, whereas the first site of inorganic lead is enzyme inhibition (e.g., enzymes involved in heme synthesis). 

Mercury Species in the Environment Most of the mercury encountered in water/ soil/sediments/biota (all environmental media except the atmosphere) is in the form of inorganic mercuric salts and orga-nomercurics. The presence of a covalent C—Hg bond differentiates organomercurics from inorganic mercury compounds that merely associate with the organic material in the environment but do not have the C—... 

PHYSICAL PROPERTIES most inorganic mercury compounds are white powders or crystals mercuric sulfide (cinnabar) is red and turns black when exposed to light insoluble in hydrochloric or similar acids soluble in nitric acid and hot concentrated sulfuric acid water soluble salts include mercuric chlorate, cyanide, chloride and aeetate oxides, sulfates and most other common salts, including mercurous chloride, are sparingly soluble or deeomposed in water appearances vary from eolorless crystals to yellow, red (oxide, sulfide, iodide), and brown or black (sulfide) MP (-39°C, -38°F) BP (357 C, 674 F) DN (13.534 gW at 25°C) SG (13.5) VD (not applicable) VP (0.0012 mitiHg at 20°C). 

Inorganic mercury compounds (ionogenic) and organic compounds such as methyl mercury, ethyl mercury and so on may occur in water. The latter may be concentrated to a certain extent in organisms (e.g. fish). Although the absolute quantity involved is mostly only very small, in view of their... 

Problems of removal of mercury from aqueous effluents are more comphcated in plants that manufacture a variety of inorganic and organic mercury compounds it is generally best to separate the effluent streams of inorganic and organic mercurials. When phenyhnercuric acetate is precipitated from its solution in acetic acid by addition of water, the filtrate is collected and reused for the next precipitation. This type of recycling is necessary not only for economic reasons but also to minimise recovery operations. 

To help prevent this, the U. S. Public Health Service has recommended a maximum limit of 0.5 ppm mercury in any food. If the fish are to have less than this level of methyl mercury and the concentration factor is 3,000, then the surrounding water in which the fish live should have less than 0.16 ppb (parts per billion). Currently the oceans have about 0.1 ppb, but it is not known whether this is in the form of organic or inorganic compounds.8 It is also not known whether fish can convert inorganic mercury into methyl mercury.8 However, a large number of microorganisms can do this, so possibly its usual form is unimportant. 

Logar, M., M. Horvat, H. Akagi, and B. Pihlar. 2002. Simultaneous determination of inorganic mercury and methylmercury compounds in natural waters. Anal. Bioanal. Chem. 374 1015-1021. 

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