Colloidal Silver

What is colloidal silver and can I use it for organic livestock?

By Brian Baker, Ph.D.

Silver naturally occurs in small concentrations in colloidal clays. These clays are called colloidal silver. Natural mineral deposits such as colloidal clays are permitted for use in organic livestock production under the NOP. To determine that it is natural, an interested user should demonstrate that the material is mined and mechanically processed without any additional chemical processing or synthetic additives.

Users verify that colloidal silver products comply with other applicable federal and state regulations for use in livestock feed. Silver is not recognized as an essential nutrient by the Association of American Feed Control Officials. The use of silver is prohibited under the Pasteurized Milk Ordinance. The FDA Center for Veterinary Medicine has also issued warnings that the use of colloidal silver in food-producing animals constitutes a potentially serious public health concern because of the possilbity of residues in milk or meat.

Even though colloidal silver may comply with NOP regulations for nonagricultural nonsynthetic substances used in feed, its legal use in livestock operations may be limited by other federal and state regulations.

Revised and updated in September 2016 by OMRI Technical Director Johanna Mirenda. This article was originally published in the Winter 2009 edition of the OMRI Materials Review newsletter.