Review article
CHEMICAL ASPECTS OF THE ECOTOXICOLOGY OF MERCURY AND ITS COMPOUNDS
Gordana Pavlović
orcid.org/0000-0002-2317-3348
; Tekstilno-tehnološki fakultet, Zagreb, Hrvatska
Snježana Siketić
; Tekstilno-tehnološki fakultet, Zagreb, Hrvatska
Abstract
The extreme toxicity of mercury in its many forms renders the understanding of its chemistry a matter of utmost importance.
High mercury toxicity is less connected with its elementary form than with its inorganic salts or organomercury compounds. The three chemical forms vary in effects due to differences in their absorption and metabolism, among other factors. The toxicity of its elementary form is connected with inhalation of mercury vapours, not ingestion of liquid mercury. Aside from the type of chemical compound, the main factor affecting mercury toxicity is its oxidation state (+I or +II). The inorganic compounds of mercury(II) are basically more toxic than mercury(I) compounds due to their better water solubility and absorption in the gastrointestinal tract. Furthermore, the Hg2+ ion exhibits remarkable tendency for complex formation, as opposed to the mercury(I) ion, which exists only as Hg22+ cation. Toxicity of organomercury compounds, and especially of its alkyl and aryl derivatives, is based on lyophilicity (which enables easy transport through brain membranes) as well as thiophilicity (formation of strong Hg-S bonds with –SH amino acid groups while inhibiting the protein function in the body).
Organomercury compounds are very strong poisons of the first category.
The use of mercury in instruments such as thermometers, barometers, etc. has been forbidden in the Republic of Croatia since April 2010.
The knowledge about mercury and its compounds is a basis for understanding intoxication modes, but at the same time brings effective detoxication processes based on chelation therapy. The quality of law regulations can be based only on deep understanding of the fundamental chemical behaviour of mercury and its compounds.
Keywords
mercury and its compounds; toxicity; ecological accidents; antidotes; laws and regulations
Hrčak ID:
67035
URI
Publication date:
19.4.2011.
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