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Colloidal silver



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Carbon nanotubes
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Colloidal silver
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Colloidal silver refers to microscopic particles of silver that are held in a liquid suspension. A colloid is technically defined as particles which remain suspended without forming an ionic, or dissolved solution. The broader commercial definition of colloidal silver includes products that contain various concentrations of ionic silver, silver colloids, ionic silver compounds or silver proteins in purified water. Colloidal silver with concentrations of 30 parts per million (ppm) or less are typically (but not always) manufactured using an electrolyte process, whereas colloidal silver with higher concentrations of 50 ppm or more are usually (but not always) either silver compounds such as silver chloride and silver iodide or are solutions that have been bound with a protein to disperse the particles.

Additional recommended knowledge

Contents

History and Applications

Prior to 1938, colloidal silver was widely used by physicians as a mainstream antibiotic.[1] It was produced by pharmaceutical companies under various names, including Protargol. But the electro-colloidal production process was costly and the pharmaceutical industry developed fast-acting, less-expensive sulfa drugs and penicillin. Silver nitrate solutions were introduced by Credé in 1880 to protect newborn infants' eyes from infection.[2], but have largely been replaced by antibiotic ointments since 1978[3][4]. This silver nitrate is a solution of a silver salt, not a suspension of colloidal silver. Silver-based cremes have been used in burn centers for more than 100 years.[5] Colloidal silver can be used to keep drinkable water potable over a long period.[citation needed] Concentrations of colloidal silver at 5 parts per million or higher have been found to kill numerous infectious bacteria.[6] Colloidal silver has been approved by the EPA as a disinfectant for hospitals and medical centers.[7]

Method of Action

Colloidal silver might kill bacteria by inhibiting the expression of enzymes and other proteins essential to ATP production. [8] It can be expected to have similar effects on human enzymes.

Toxicities

Argyria

Main article: Argyria

Long-term intake of silver products may result in a condition known as argyria, one symptom of which is a blue or gray discoloration of the skin.[9] It occurs when sunlight interacts with silver deposited in the skin, in the same way that silver particles in photographic film darken when exposed to sunlight. It can occur both via ingestion of silver, or through topical application of silver to the skin.[citation needed] While generally considered permanent[10], some have claimed to have reversed it.[11] Death from argyria has been reported from as little as four months use of oral colloidal silver[12] , and cases of kidney damage, stomach distress, and headaches have been reported, as well as cases of brain and nerve damage.[13][14] [15][16]An FDA “Talk Paper” references silver ingredients and silver salts that includes silver proteins, silver chloride and silver iodide. They claim that the use of these “gelatinous” silver solutions have resulted in cases of argyria.[17] Advocates claim that almost all known cases of argyria resulted from use of highly concentrated silver compounds such as silver oxide, silver nitrate or silver chloride and not the electrolyte-manufactured solutions, which contain only ionic and colloidal silver and typically comprise silver concentrations of 30 ppm or less.

Advocates assert that, under careful use of properly produced colloidal silver, argyria is virtually impossible,[18] though these claims are anecdotal and have not been confirmed by scientific study. Advocates also claim that very few if any current cases are known to exist. They view the entire controversy as an orchestrated scare tactic by special interests who they say deliberately exaggerate and mislead people away from colloidal silver products. However, verified cases of argyria continue to be reported and proven, sometimes making the television news programs.[19][20][21].

Many scientific articles report cases of argyria after ingestion of colloidal silver [22] [23] [24] [25] [26] [27].

Government reactions

The U.S. Food and Drug Administration (FDA) banned over-the-counter sales in the U.S. of any product claiming to have therapeutic value, health benefits, or making any medical claims, unless it has undergone the rigorous safety and efficacy testing required of pharmaceuticals. As such testing has not been conducted with colloidal silver, the product now has the status of a dietary supplement in the US (dietary supplements cannot claim to cure diseases, only that they "support healthy functioning").[28] The FDA has issued warnings to Internet sites selling or promoting colloidal silver as an antibiotic or for other medical purposes.[29] If no medical benefits are claimed, colloidal silver is sold as a supplement, and as long as the products comply with all other FDA regulations, its sale is considered legal.[30] In 2002, the Australian Therapeutic Goods Administration made a similar ruling.[31]

Differing preparations

The term, "colloidal silver", has been used inaccurately by some to advertise products which are solutions of either silver salts, or proteins bound with silver[citation needed]. This misrepresentation contributes to over-all confusion about the term "colloidal silver". In order for a mixture to be a true silver colloid, the silver atoms must be tiny metallic particles suspended in a liquid. Confusion around colloidal silver is increased by the fact that there is more than one manufacturing process, and that these lead to a number of significantly different products that have differing properties[citation needed], all of which go by the name "colloidal silver".

Preparations called 'colloidal silver' include:

  • Electrolytic silver (most common method used today)
  • Ground silver (standard form of colloidal silver pre-World War II)
  • Electrolysis of salt solution (produces a yellow product)

References

  1. ^ Journal of American Science, 3(3), 2007, Ma Hongbao, Horng Dengnan, Cherng Shen, Colloidal Silver [1]
  2. ^ http://www.accessmedicine.com/content.aspx?aID=727485
  3. ^ neonatal gonoccal prophylaxis [2]
  4. ^ Neonatal Conjuctivitis [3]
  5. ^ Complementary Medicine - Information about complementary & alternative medical therapies, Cedars-Sinai Health System
  6. ^ BYU Study
  7. ^ http://www.newstarget.com/013028.html
  8. ^ http://aem.asm.org/cgi/reprint/71/11/7589.pdf
  9. ^ Skin dicoloration folllowing the administration of colloidal silver in cystic fibrosis PMID 18025945
  10. ^ Believe it or not- silver still poisons PMID 18025945
  11. ^ Argyria-Reversal Claim
  12. ^ Myoclonic status epilepticus following repeated oral ingestion of colloidal silver PMID 15111684
  13. ^ Agyria: a report of a case associated with abnormal elec troencephalographic and brain scan findings PMID 3112046
  14. ^ "Joshua B Glenn, Anna N Walker: Argyria In An Elderly Man. The Internet Journal of Dermatology. 2002. Volume 1 Number 2 available online
  15. ^ Argyria and convulsive seizures caused by ingestion of silver in a patient with schizophrenia PMID 8783381
  16. ^ Brain involvement in generalized argyria PMID 6705320
  17. ^ [4] Can colloidal silver cause argyria?
  18. ^ Silvermedicine.org: Argyria - Colloidal Silver Safety.
  19. ^ http://educate-yourself.org/lte/colloidalsilver27jan05.shtml
  20. ^ http://www.utopiasilver.com/faq/can-colloidal-silver-cause-argyria.htm
  21. ^ FoxNews.com: Man Claims Skin Treatment Turned Face Permanent Blue
  22. ^ Kalouche H, Watson A, Routley D , Blue lunulae: argyria and hypercopprecaemia , Australas J Dermatol. 2007 Aug;48(3):182-4
  23. ^ Baker CD, Federico MJ, Accurso FJ, Case report: skin discoloration following administration of colloidal silver in cystic fibrosis, Curr Opin Pediatr. 2007 Dec;19(6):733-735 PMID 18025945
  24. ^ Chang AL, Khosravi V, Egbert B, A case of argyria after colloidal silver ingestion, J Cutan Pathol. 2006 Dec;33(12):809-11 PMID 17177941
  25. ^ Wadhera A, Fung M, Systemic argyria associated with ingestion of colloidal silver, Dermatol Online J. 2005 Mar 1;11(1):12 online: [5]
  26. ^ Brandt D, Park B, Hoang M, Jacobe HT., Argyria secondary to ingestion of homemade silver solution, J Am Acad Dermatol. 2005 Aug;53(2 Suppl 1):S105-7
  27. ^ McKenna JK, Hull CM, Zone JJ, Argyria associated with colloidal silver supplementation, Int J Dermatol. 2003 Jul;42(7):549
  28. ^ COLLOIDAL SILVER NOT APPROVED FDA reports "Use of colloidal silver ingredients in food-producing animals constitutes a potentially serious public health concern", Wednesday, February 12, 1997
  29. ^ FDA warning healthymagnets
  30. ^ FDA ISSUES FINAL RULE ON OTC DRUG PRODUCTS CONTAINING COLLOIDAL SILVER FDA, 1999-08-17
  31. ^ TGA. Regulation of colloidal silver and related products Therapeutic Goods (Excluded Goods) Order No. 1 of 2005 [6] revoked Therapeutic Goods (Excluded Goods) Order No. 1 of 2004. 9 November 2005 update

See also

 
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Colloidal_silver". A list of authors is available in Wikipedia.
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