Academic calls for health warnings

29 July 2002
A Waikato University chemist is calling for health warnings to be placed on alternative health products that contain colloidal silver.

Dr Michael Mucalo, of Waikato University’s Chemistry Department, has voiced concern about some health supplements that use sub-microscopic traces of silver, saying that users aren’t being warned about potential health risks.

Dr Mucalo, whose speciality is colloidal metals, says that the so-called colloidal silver products expose users to the possibility of developing Argyria.

Argyria is a condition whereby the skin, nails, mucous membranes, eyes and internal organs can acquire a permanent bluish-grey discoloration. The condition results from the deposition of silver after long periods of exposure from ingestion. How much silver and how long it takes to develop is variable and depends on the individual and on the concentration of silver in the supplement being ingested. Among areas where the unusual pigmentation can appear are the face, ears, neck and hands.

Dr Mucalo is worried that some colloidal silver products being marketed do not actually contain colloidal silver, which is basically a dispersion of tiny submicroscopic particles of metallic silver, but in fact contain "ionic" or dissolved silver which can cause this condition. The most at risk, he feels, are users that are taking ongoing repeated doses over long periods of time, as this action could effectively build up silver deposits in the blood stream putting them at risk.

“One off topical use of a low concentration colloidal silver solution shouldn’t expose the user to danger. However, there are no health warnings to say that overuse can lead to Argyria, nor are manufacturers required to say how much silver is in the mixture.”

In 1999, the United States FDA ruled, "ionic silver salts and highly concentrated mild silver protein" all being alternative names for colloidal silver products, "clearly are not safe for OTC use"
They also concluded that a full-unbiased study of the use of these solutions in humans was needed.

Over the counter colloidal silver products must have less than 10ppm of silver to be legal within New Zealand. Any amount over that classifies that product as a Pharmacy Only medicine.

Last year a number of colloidal silver products were tested by ESR for their silver levels. Some were found to have exceeded the limited of 10ppm. "Kits" are also available which enable the user to generate their colloidal silver by battery or electrically powered means. This could lead to solutions of silver of varying concentration.

Cases of Argyria, which have been attributed to the use of supplements containing colloidal silver, have been reported in the United States and Australia. A recent Australian case saw a child’s skin turn silver grey after the child had been taking a colloidal silver solution.

“To the best of my knowledge no cases have been reported yet in New Zealand,” says Dr Mucalo. “However, it would be negligent to assume that it can’t happen here. On some products it is advised to give children a teaspoonful a day…a perturbing thought given one is effectively giving the child a dose of a heavy metal. It is also possible that the condition can be misdiagnosed for other maladies by doctors".

“If people are going to use alternative health supplements, then they should be presented with the facts so they can make an informed choice, just as it is with cigarette products. The New Zealand Ministry of Health needs to take the initiative of ensuring some type of warning goes on the packaging. In fact, the Australian Therapeutic Goods Administration which moderates medicinal products in Australia has already been placing warnings on some silver-containing products".

Colloidal silver products have been touted as a natural antibiotic supplement with wild, unproven claims being made that it can cure cancer and AIDS. It is available through health food stores, pharmacies and the Internet.