Toxicity: Keeping It Safe

As with any treatment, it is advisable to be informed about any negative side effects that might be associated with taking colloidal silver. The previous chapter illustrated that, under normal circumstances, it is difficult for the body to accumulate excess amounts of silver, even when ingesting high daily amounts of colloidal silver. How, then, does toxicity occur? Perhaps prior to how toxicity occurs, we should investigate whether it actually does occur as a result of treatments involving internal colloidal silver. Colloidal and nanosilver have been in the limelight in recent years. As a result, there is an accumulation of solid, scientific research to consider.

In general, silver is relatively nontoxic to mammalian cells. Most humans today are exposed daily to very low levels of silver from food and drinking water and, to a smaller extent, even from the air we breathe.

The estimated fatal dose of AgNO3 for humans is 1.4×105μg/kg−1. However, most of this data was extrapolated from studies on animals and extended to humans, a process that is inherently prone to errors.

It is to be noted that the toxicity of silver nitrate is millions of times higher than that of silver nanoparticles.

After exposure and absorption, silver nanoparticles are transported by the bloodstream. If these are the wrong size or shape, silver can accumulate in organs and tissues such as the liver, skin, kidney, spleen, heart, lung, olfactory bulb, corneas, gingival mucous membranes, brain, and testes. Silver also can re-precipitate in these organs; ions reduced to metallic silver and nanoparticles can occur.

It should also be noted that mostly bigger, asymmetrical shapes of silver nanoparticles can cause toxic effects such as inflammation, cell activation, or depletion of glutathione levels in association with mitochondrial dysfunction and ROS production. AgNPs may interact with sulfur-containing proteins and enzymes (such as thioredoxin peroxidase, thioredoxin, superoxide dismutase protein, and glutathione, the most sensitive indicator of the cell to silver toxicity) and at least partially deactivate them. Free radical accumulation can also initiate an inflammatory response.

The following are some review articles useful in helping to form conclusions regarding silver mechanism and toxicity.

They are also included in the reference list at the end of the book: 

Review Article: “A Pharmacological and Toxicological Profile of Silver as an Antimicrobial Agent in Medical Devices”

A section of this journal article discusses the occurrence of soft tissue and bone damage as a result of silver treatments. The authors of the article report, after analysis of the published literature, that silver does not, in any form, cross the blood/brain or blood/cerebrospinal fluid (CSF) barrier. Thus, brain damage due to silver treatments is highly unlikely. Furthermore, silver is not absorbed into the central or peripheral nervous systems, virtually eliminating the opportunity for nerve damage. Hepatic (liver) damage has not been confirmed. While silver can cause temporary changes to some chemical levels in the body (triglycerides, cholesterol, etc.), the fluctuations are not permanent, nor do they cause damage. Renal (kidney) damage has not been observed. Although silver can enter the bone marrow, there are no significant negative effects. Cases of hypersensitive or allergic reactions are mostly believed to be the results of additives.

Article: “A Shot in the Arm for Old Antibiotics”

This report discusses a group of Harvard scientists and includes a paragraph about their toxicity studies. The researchers found that the amount of silver used to enhance the effects of the antibiotics were significantly lower than the amount needed to harm cultured human cells.

Lab Report: “An In Vivo Human Time-Exposure Investigation of a Commercial Silver Nanoparticle Solution”

These researchers conducted a sophisticated, double-blind study to investigate the effects of exposure to oral nanosilver. Volunteer research subjects took the silver for periods of three, seven, or fourteen days (three groups of twelve subjects, a total of thirty-six subjects).

The following results were statistically significant:

  • The silver did not cause negative changes to body metabolism, blood, or urine.
  • Examined organs, (heart, lungs, abdominal) did not show evidence of damage to form or structure.
  • Analysis of the sputum (spit) did not show negative changes, such as inflammatory proteins.


Report: “American Biotech Labs’ Nanosilver Proven Safe for Humans”

Many commercial products seek U.S. Environmental Protection Agency (EPA) approval. To receive it, products must undergo rigorous, strictly controlled scientific studies. This report discusses the 160 studies, comprising roughly 10,000 individual antimicrobial tests, that one company has undertaken to test their nanosilver products. The results indicated that nanosilver does not damage human cells; ingested nanosilver was not harmful to the human study subjects; and injected nanosilver was nontoxic to test animals. They found no evidence of heavy metal poisoning, an increase in cancer, or higher rate of cell mutation. As a result of these and other studies, the EPA has awarded this company several silver product registrations.

Research: “Genotoxicity, Acute Oral and Dermal Toxicity, Eye and Dermal Irritation and Corrosion and Skin Sensitisation Evaluation of Silver Nanoparticles”

This experiment, conducted in Korea, attempted to see whether nanosilver causes irritation or damage to genes, skin, or eyes. The experiment reports that no clinically significant abnormal signs, including mortality (death), were observed.

Colloidal Silver Conclusion 5: The overwhelming majority of reliable clinical research shows that responsible, appropriate colloidal silver treatments are nontoxic or otherwise harmful to the human body.

What is very important to note in the above conclusion are two words: “responsible” and “appropriate.” Irresponsible and inappropriate colloidal silver treatments, on the other hand, do harbor the potential for damage to the human body.

It is very easy to manufacture colloidal silver with a battery and silver wires; however, the particles manufactured with home kits are electrically charged, and their size is not controlled. As a result, they tend to quickly clump together, grow very big and heavy, and finally settle at the bottom of the glass. If ingested, these large silver clumps will either be non-absorbable, or else they will become trapped in the body tissues, like debris caught in the bottom of a sieve. This silver debris is potentially troublesome, and a handful of people have experienced problems as a result, always due to homemade silver from garage kits.

Two Rules to Avoid Toxicity

To avoid toxicity, colloidal silver users should pay attention to the following two rules.

Rule #1: Use professionally made colloidal silver products.

There are many seemingly well-documented articles about how you can make your own silver products and save money. At the moment, the only guaranteed safe colloidal silver products are those produced by experts, under strictly controlled conditions, in reputable laboratories. Any money saved by do-it-yourself (DIY) silver-making is not worth the risk to your health.

Professionally made colloidal silver products have many advantages:

  • They do not include silver salts, which appear to overreact with body tissues and have been shown to have significantly higher toxicity for humans.
  • They can and should contain coated particles. This issue will be discussed more than once in this book, but coated nanosilver particles operate in a time-released fashion, spreading the antimicrobial silver ions into the body in a slow, controlled manner. Uncoated nanosilver particles tend to clump together quickly, depositing in body tissues. This makes it very difficult for the body to eliminate them naturally.
  • They are of the correct size and shape. Evidence shows that silver nanoparticles between 5 and 30nm can be handled easily and safely eliminated by the body. The shape of the particles should be symmetrical, as asymmetrical shapes appear to have a much greater potential for toxicity.


Rule #2: Get professional advice about dosages.

While results vary by individual, the general findings are that professionally made colloidal silver is safe, in small quantities. When talking about dosages, silver is measured in parts per million (PPM) or mg/L, which indicates how much silver is suspended in how much liquid. What many people fail to realize is that, for example, 1mg can be suspended in a shot glass or a full bottle of water. These liquids will have very different ppms, because the same silver amount is dissolved in different amounts of water, but the effect in the body will be the same. Why is that? Because in both cases, 1mg of silver is ingested and suspended in the body fluids. The final body concentration of silver after ingestion will be the same number of ppm. In short, do not confuse the PPM of the drinking bottle with the final ppm that will be established in the body; the ppm does not matter as much as the quantity of silver ingested. There are conversion charts for ppm in the appendix of this book.

Due to the fact that a large number of workers are exposed to silver daily while on the job, there have been a variety of governmental studies to assess safe exposure levels. In some cases, these workers were exposed to much higher amounts of silver than the average person. The studies found that silver toxicity was consistently rare; a discussion of these rare cases is included in the next chapter.

Please keep in mind that, due to the huge variety and inconsistency of the colloidal silver commercially available, the requirement and safety recommendations are likely flawed.

To find out just how much silver is safe to be taken orally, consult The Silver Safety Council (SSC), an organization of knowledgeable and reputable doctors, scientists, and medical professionals. Their website at contains a wealthy of reliable information and guidance for safe and effective use of silver.  

On the website, The SSC discusses the U.S. EPA reference dose (RfD), the EPA safety guideline for daily oral silver consumption. If overall, daily silver consumption is 100 percent, the EPA recommends using no more than 25 percent of the daily recommended allowance for active oral silver intake, leaving 75 percent for passive ingestion of silver from food, water, and air. According to the EPA, the oral RfD for silver is 0.005mg/kg/day, based on body weight.[1]The SSC has devised a way to calculate the amount of silver that is most beneficial and correct for each individual, the silver safety calculation. By combining EPA recommendations with this calculation, the SSC has devised the silver safety pyramid, which provides easy calculations for safe doses of silver on a daily, short-term, or lifetime basis.[2]

Colloidal Silver Conclusion 6:Professionally made colloidal silver taken in the appropriate doses for your body is virtually nontoxic.

[1] “EPA R.E.D. Facts: Silver.”

[2] These calculations are on their website at

“This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.”