Arsenic

Arsenic is a metal found in elemental, inorganic and organic forms.  The inorganic and organic forms exist as trivalent (arsenite) and pentavalent (arsenate) forms.  Most commercially available arsenic-containing products are produced from arsenic trioxide, one of the more toxic trivalent inorganic compounds.  Acute ingestion, usually in the context of deliberate self-poisoning, is followed by severe gastroenteritis with a characteristic sequential life threatening multiple organ failure. Subacute exposures occur from industrial accidents, food contamination and ingestion of arsenic-containing herbal medicines. Chronic intoxication usually follows long-term drinking of contaminated artesian water. The organic arsenoids found in seafood are non-toxic.

References

• Graeme KA, Pollack CK.  Heavy metal toxicity: arsenic and mercury.  Journal of Emergency Medicine 1998; 16(1):45-46.
• Ratnaike RN. Acute and chronic arsenic toxicity. Postgraduate Medical Journal 2003; 79: 391-396.
• Xu Y, Wang Y, Zheng Q.  Clinical manifestations and arsenic methylation after a rare subacute arsenic poisoning accident. Toxicological Sciences 2008; 103(2):278-284.