Argyria

Argyria or argyrosis (from Ancient Greek: ἄργυρος argyros silver) is a condition caused by inappropriate exposure to chemical compounds of the element silver, or to silver dust. The most dramatic symptom of argyria is that the skin turns blue or bluish-grey. It may take the form of generalized argyria or local argyria. Generalized argyria affects large areas over much of the visible surface of the body. Local argyria shows in limited regions of the body, such as patches of skin, parts of the mucous membrane or the conjunctiva.

The terms argyria and argyrosis have long been used interchangeably, with argyria being used more frequently. Argyrosis has been used particularly in referring to argyria of the conjunctiva, but the usage has never been consistent and cannot be relied on except where it has been explicitly specified.

Biological effect



In animals and humans chronic intake of silver products commonly leads to gradual accumulation of silver compounds in various parts of the body. As in photography (where silver is useful because of its sensitivity to light), exposure of pale or colourless silver compounds to sunlight decomposes them to silver metal or silver sulfides. Commonly these products deposit as microscopic particles in the skin, in effect a dark pigment. This condition is known as argyria or argyrosis.

Chronic intake also may lead to silver pigments depositing in other organs exposed to light, particularly the eyes. In the conjunctiva this is not generally harmful, but it also may affect the lens, leading to serious effects.

Localised argyria often results from topical use of substances containing silver, such as some kinds of eye drops. Generalized argyria results from chronically swallowing or inhaling silver compounds, either for medical purposes, or as a result of working with silver or silver compounds.

Argyria is generally believed to be irreversible, with the only practical method of minimising its cosmetic disfigurement being to avoid the sun, but laser therapy has been used to treat it with satisfactory cosmetic results. The Agency for Toxic Substances and Disease Registry (ATSDR) describes argyria as a "cosmetic problem", which is not physically harmful, but others state that in severe cases it can be disfiguring.

Generally silver is only slightly toxic to humans, so the risk of serious harm from clinical exposure is slight. Clinical use of silver or silver compounds includes the treatment of external infections or in medical appliances. Chronic ingestion or inhalation of silver preparations (especially colloidal silver) can lead to argyria in the skin and other organs. This is not life-threatening but commonly is cosmetically undesirable.”

The reference dose, published by the United States Environmental Protection Agency in 1991, which represents the estimated daily exposure which is unlikely to incur an appreciable risk of deleterious effects during a lifetime, is 5 µg/(kg*d).

History



Since at least the mid 19th century, doctors have known that silver or silver compounds can cause some areas of the skin and other body tissues to turn grey or blue-grey. Argyria occurs in people who ingest or inhale silver in large quantities over a long period (several months to many years). People who work in factories that manufacture silver can also breathe in silver or its compounds. In the past, some of these workers have become argyric. However, the level of silver in the air and the length of exposure that caused argyria in these workers is not known. Historically, colloidal silver, a liquid suspension of microscopic silver particles, was also used as an internal medication to treat a variety of diseases. In the 1940s, they were discontinued due to the development of safe and effective modern antibiotics and concern about argyria and other side effects of silver products.

Colloidal silver



Alternative medicine

Since the 1990s, "colloidal silver" has been marketed as an alternative medicine product, with unsubstantiated claims of effectiveness which are illegal in some jurisdictions . Medical authorities advise against the use of such colloidal silver preparations, as does the published medical literature, because of their lack of proven effectiveness and the risk of side effects.

Colloidal silver preparations primarily deliver inactive metallic silver, rather than the active microbicidal silver ion. There is no scientific evidence to support the effectiveness of colloidal silver in vivo. Some in vitro studies demonstrate an anti-bacterial effect of colloidal silver, although one study in 2004 of a colloidal silver solution marketed on the Internet showed no such antimicrobial activity.

Cases

A prominent case from ingestion of a silver compound (not colloidal silver) was that of Stan Jones of Montana, a Libertarian candidate for the United States Senate in 2002 and 2006. Jones acquired argyria through consumption of a home-made silver product that he made due to fears that the Year 2000 problem would make antibiotics unavailable. The peculiar colouration of his skin was featured prominently in media coverage of his unsuccessful campaign, though Jones contends that the best-known photo was "doctored". Jones promised that he was not using his silvery complexion as a gimmick. He continues to promote the use of colloidal silver as a home remedy. He has said that his good health, excepting the unusual skin tone, is the result of his use of colloidal silver.

In 2007 press reports described Paul Karason, an American man whose entire skin gradually turned blue after consuming colloidal silver made by himself with distilled water, salt and silver, and using a silver salve on his face in an attempt to treat problems with his sinus, dermatitis, acid reflux and other issues. Karason died on September 23, 2013 after suffering a heart attack and stroke.



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