The human health effects from exposure to low environmental levels of elemental mercury are unknown. Very high mercury vapor concentrations can quickly cause severe lung damage. At low vapor concentrations over a long time, neurological disturbances, memory problems, skin rash, and kidney abnormalities may occur.
In soil and in water, mercury can exist in either the monovalent or divalent forms as inorganic compounds. The particular valence state in which mercury exists in the environment (Hg0, Hg+, Hg2+) is dependent upon multiple factors, including the pH and redox potential of the particular medium and the strength of the ligands present.
Mercury is highly toxic to most forms of life. When eaten in large amounts, some inorganic mercury compounds can be very irritating and corrosive to the digestive system. If repeatedly eaten or applied to the skin over long period of time, some inorganic mercury compounds can cause effects similar to what is seen with long term mercury vapor exposure, including neurological disturbances, memory problems, skin rash, and kidney abnormalities.
Some organomercurials, in particular low-molecular-weight alkyl compounds, are considered even more toxic to humans because of their high chronic toxicity with respect to various, largely irreversible, defects of the neryous system.
An
element of mercury
