SILVER - Nature's Water Purifier
Articles within this research page: from http://www.doulton.ca/silver.html
Silver's Importance to Health
Feb 27, 1997
While silver's importance as a bactericide has been documented only since the late 1800s, its use in purification has been known throughout the ages. Early records indicate that the Phoenicians, for example, used silver vessels to keep water, wine and vinegar pure during their long voyages. In America, pioneers moving west put silver and copper coins in their water barrels to keep it clean.
In fact, "born with a silver spoon in his mouth" is not a reference to wealth, but to health. In the early 18th century, babies who were fed with silver spoons were healthier than those fed with spoons made from other metals, and silver pacifiers found wide use in America because of their beneficial health effects.
Helping to Stop Legionnaire’s Disease
Recent research compared silver-copper ionization with the use of high temperatures to destroy bacteria. Contaminated cold water re infected the hot water system even when temperatures in hot water heaters reached as high as 60 degrees Centigrade. But experiments showed that even at lower water temperatures, ionization of soft water with silver and copper ions was effective against the bacteria.
“Ionization showed better results." said Nigel Pavey principal research engineer for BSRIA Water Services Technology Centre in Berkshire. And to make certain its benefits are widespread, "there should be more emphasis on copper-silver ionization in Legislation,' he said.
Importance in Burn Therapy
Keeping Plastic Clean
Promoting Skin Growth
In a treatment developed by Mountain Medical Specialties of Lakemont. GA. a silver-coated fabric is used to cover the wound. A miniature battery is connected to the fabric to begin a flow of silver ions to encourage normal skin growth and eliminate bacteria which generally prevents complete regeneration of the skin and nerve function. This method has actually restored the natural skin patterns and sensations in the palms of hands.
Eliminating Harmful Bacteria
"The applications for ionization are almost endless," Ganim said. Currently ionization is used by chicken farmers to reduce bacteria and fungus without affecting the health of the chickens. 'We think this system will also work for citrus growers' who routinely spray their trees with chemicals.
Keeping Oxygen Handling Safe
Limiting sparks during oxygen production is of critical importance. Because silver will not ignite, even at its melting point, the oxygen compressor design code issued by the Industrial Gas Council in Brussels, requires that wherever contact between metals occurs, one of the facing metals must be silver and the other a high-nickel alloy. This combination provides the lowest probability of sparking during high-speed compressor operation. The seals in compressor and pumping equipment are also silver to minimize any possibility of friction which could ignite a fire. Oxygen pump seals must be manufactured to extremely close tolerances, and the silver also allows fine machining,
Helping People With Allergies
For more information on any of these medical uses of
Silver Copper System Works Better
than High Temperatures to Destroy Deadly Bacteria
Following major outbreaks of Legionellosis (Legionnaire’s Disease) in the United Kingdom in the late 1980’s the government came out with safety guidelines for cooling towers which all but eliminated the problem. Now, however the government has turned its attention to hot and cold service which now accounts for a significant number of identified cases of Legionnaire’s disease in the UK
Silver is playing a key role in efforts to prevent these deadly outbreaks. With funding from the government and private industry the building and services research and information association (BSRIA) has completed a two year research project to compare the effectiveness of using silver and copper ionization against the storage of water at high temperatures to destroy the bacteria.
“Ionization showed better results” says Nigel Pavey, Principal Research Engineer for BSRIA. For example, contaminated cold water re-infected the hot water system even when temperatures in hot water heaters reached as high as 60 degrees Centigrade. Experiments showed that even at lover water temperatures, ionization of soft water with silver and copper ions was effective against legionella. In showers and hot and cold faucets, ionization was effective against the bacteria if silver concentration was around 40 micrograms per liter.
Hard water presented a problem however. The electrodes used for ionization frequently scaled up and the high level of dissolved solids in the water took the silver ions out of the solution. When silver ionization levels could be kept up using scaling controls, the technique was effective.
BSRIA’s findings were published in Ionization Water Treatment for Hot and Cold Water Services available from BSRIA. For more information fax BSRIA at 44-1344-487575
Silver - Reliable Alternatives to Chlorine
Silver Water Purification Systems
Offer Reliable Alternative to Chlorine
Laguna Niguel, CA (March 25, 1997) - Silver based water purification systems offer the most reliable and cost effective alternative to chlorine, a chemical that is increasingly coming under fire for the carcinogenic by products it leaves in water, according to David Eaton, secretary of The Institute of Water Ionization Technologies in the United Kingdom and technical director of Roseland Hydronics PLC.
Speaking at the annual meeting of The Gold & Silver Institutes in Laguna, Niguel, CA. this week Eaton said progressively restrictive legislation is confronting the use of chemicals, especially chlorine, which for nearly a century. has been the primary medium for water disinfection.
With increasing pollution, utilities are forced to put far more chlorine into the supply chain, Eaton explained. The chemical reaction that oxidizes impurities when chlorine is added, also forms carcinogenic byproducts. "Of course these same byproducts have been generated by chlorination for a long time but never in the quantities that are now being seen," he said.
Silver offers a healthy alternative. The metal has long been known for its biocidal properties, Eaton noted. The Ancient Phoenicians. who stored wine in silver urns to preserve it, provide one of the earliest recorded examples of the metal’s use for water purification.
Applying modern technology to this old fashioned principle, The Institute of Water Ionization Technologies has developed silver ion generators for municipal water supplies. The market for silver ionized swimming pool systems has expanded significantly in the US and overseas, Eaton said. But in Britain, silver ionization is being developed for mainstream water systems. Machines used to clean primary water must be much larger and more powerful than small swimming pool units, and require accurate control mechanisms to ensure that levels of silver are maintained and kept within drinking water standards.
Eaton discussed a recent project funded by the UK Department of the Environment to study the control of Legionnaires disease by using silver ions. The disease is named after Legionella pneumophilia, an organism that is widespread in small quantities within natural water sources. The bacteria becomes lethal at a water temperature of 95 degrees F and can be killed at temperatures between 135 and 140 degrees F.
Of three tests, silver/copper ions in soft water produced the best results. The copper ion disrupted the enzyme structures of the cell allowing the silver ion to penetrate inside where it rapidly killed the cell's life support system. US regulations allow a silver level of 100 ppb in drinking water, but a silver level of only 20 ppb kills Legionella.
A new European Union Drinking Water Standard in draft form has removed any upper limit for silver in drinking water following the World Health Organization's Guidelines for Drinking Water Quality which States, "It is unnecessary to recommend any health-based guideline for silver as it is not hazardous to human heath.
The sale of silver based ionizers is beginning to take off in the UK and there are promising growth markets in the Scandinavia, Germany, and the Far East. We calculate that requirements for silver globally will increase to about two million ounces annually within five years.
For the complete text of Eaton’s speech, contact The Silver Institute, (202) 835-0185. For more information contact the Institute of Water Ionization Technologies, 01621869255 (fax) 01621868211.
Thanks to eye-opening research, silver is emerging as a wonder of modern medicine. An antibiotic kills perhaps a half dozen different disease organisms but silver kills some 650. Moreover, silver is virtually non-toxic. Dr. Harry Margraf of St. Louis, a pioneering silver researcher, says: "Silver is the best all around germ fighter we have."
The value of silver in medicine, and as a purifier has been acknowledged for centuries. Egyptians implanted silver plates into skulls with surgery. In Ancient Greece and Rome, people used silver containers to keep liquids fresh. When settlers moved across the American West, they would purify a container of water by putting a silver dollar in it overnight. Towards the end of the 19th century, other medicinal uses for silver were developed including the use of silver and mercury in filling cavities, and the dropping of a silver filtrate solution into the eyes of newborn babies to prevent blindness due to infection.
Scores of independent tests have shown that silver promptly kills bacteria in water and maintains water purity over long periods of time.
Russian scientists working on water recycling and purification problems for the Soviet space program have decided on silver as the best long term sanitation agent. Researching the problems of water shortage over periods of several months, as well as purification for immediate use, they determined that ionized silver provides the safest and longest lasting method of transforming polluted waste into potable water.
After testing 23 methods of purifying water, NASA has also chosen silver as the purifying agent on the Space Shuttle program.
Silver was used to provide shuttle crews with pure water for drinking, air conditioning, food preparation and other operations. By establishing 100 parts of silver per billion parts of water NASA will totally eliminate the need for chlorine! The most dramatic purification tests occurred in 1976 in a 20,000 gallon swimming pool in Nebraska. There was no disinfectant of any kind in the water. Fifty gallons of municipal sewage waste water was put into the pool. That produced a dangerous concentration of 7,000 E coli cells per 100 millilitre [half a cup] of water. Contents of the pool were then pumped through a tank containing alternating anodic and cathodic silver electrodes for disinfection. Within three hours the pool was entirely free of E. coli and the water contained only 3.2 parts of silver per billion parts of water.
The Allegheny County Health Department in Pennsylvania conducted tests in a 152,000 gallon pool which previously had been disinfected by a 50 pounds per day chlorinator. The system was replaced by a silver system for the swimming pool season of 1974 and 1975. The County Health Department took up to 50 daily samples and found that silver ions remained in the pool at the low steady rate of 20 parts per billion. The water remained free of bacteria throughout the two seasons. In contrast, 65 water samples from 30 other pools having a concentration of 700 parts per billion of available chlorine showed a mean of 1.3 pseudomonas and 7.3 staph cells per millilitre of water.
The impact of silver technology continues to grow. More than half of the American soft drink bottling companies, numerous shipping lines and a host of other enterprises in 70 countries, use silver to sterilize water. These and many other examples of the expanding use of silver in water purification have been documented by Dr. Fred Zobist and presented to the Silver Institute in Washington, D.C.
Links to Silver Institute News Letters within this site:
Vol 3, Number 5, May 73 - Silver Carbon Filter Purifies Swimming
US SURVEY OF HOSPITALS USING COPPER-SILVER IONIZATION FOR THE CONTROL OF
September 26-29, 2000,
Janet E. Stout, Y.E. Lin, V.L. Yu
VA Medical Center, Pittsburgh, PA
and the University of Pittsburgh, Pittsburgh, PA
Despite documentation of its efficacy in numerous hospitals, the long term efficacy of copper-silver ionization for controlling Legionella pneumophila in hospital water distribution systems has not been well documented. We conducted a survey of the first 13 hospitals in the U.S. that had implemented copper-silver ionization systems on their hot water systems for Legionella control. The mean bed size was 434 (range 150-700), 61% (8/13) performed transplant operations. 100% (13/13) had diagnosed cases of nosocomial Legionnaires' disease (LD). 30% of the hospitals installed copper-silver ionization because of problems and expense associated with the prior use of hyperchlorination. 50% had previously used thermal eradication. The average number of ionization flow cells installed per hospital was 3.4 (range 1-7), and the average start-up cost was $86,432. 46% (6/13) of hospitals had >30% of distal outlets positive before using ionization, and 0% had > 30% positive after installation. For 46% (6/13) of the hospitals, distal site positivity decreased to 0% positivity. When we conducted the survey, the ionization systems had been in place from 1 to 4 years. Ionization requires regular maintenance and the pH of water should be < 8.0 for optimal performance. Ionization is a viable option for controlling Legionella in hospital water distribution systems.
5th International Conference on Legionella
September 26-29, 2000, Ulm, Germany
Janet E. Stout
Infectious Disease Section,
University Drive C
Pittsburgh PA 15240USA
Disinfection of Bacteria In Water Systems by Using Electrolytically Generated Copper: Silver & Reduced Levels of Free Chlorine
AUTHORS: Yahya MT, Landeen LK, Mesina MC, Kutz SM, Schultze R, & Gerba CP
PUBLICATION REF: Canadian Journal of Microbiology 36: 109-116, 1990
The recommended minimum level of free chlorine for disinfection of public swimming pools is 1 mg/liter. This level is difficult to maintain due to the chlorine-demanding organic material introduced by bathers themselves as well as the environment. Eye and skin irritation may also occur at the minimum chlorine level needed for effective disinfection. Electrolytically generated copper/silver ions are also microbiocidal and are much less subject to degradation but are slower acting than chlorine. Therefore, the authors tested the hypothesis that using the two methods together would accomplish effective disinfection while reducing the level of free chlorine required.
MATERIALS AND METHODS:
Two 32-gallon plastic containers, one indoors (temperature range 22 to 25) and the second outdoors exposed to sunlight (temperature range 18 to 36) were filled with tap water. After chemical analysis and adjustment of pH and test levels of disinfectants, bath water and urine were added to stimulate typical swimming conditions. Four treatment regimens were tested: (1) No added disinfectants (2) Free chlorine alone at the generally recommended level of 1 mg/liter (3) Free chlorine at 0.3 mg/liter combined with copper and silver ions at a ration of 400 ug/liter of copper to 40 ug/liter of silver (4) Copper and silver ions alone at the same ratio as above. An isolate of Staphylococcus sp was employed for bacterial challenge testing since previous work had shown that staphylococci are more resistant to disinfection than are coli form bacteria. The experiment was continued for 12 weeks.
In the test of free chlorine alone, location proved to be critical. In the outdoor setting subject to strong sunlight and high temperatures, no residual chlorine could be detected 3 to 4 hours after optimization. Indoor, where environmental factors were much less extreme, a residual level of 0.1 to 0.3 mg/liter was found after 24 hours.
Bacterial counts were kept within drinking water standards (as recommended for swimming pools) by either high levels of chlorine alone or by the combination regimen of copper and silver ions with low levels of chlorine: the difference in total bacterial numbers was not significant. Hen challenged with Staphylococcus sp isolate, the combination of copper and silver ions with low levels of chlorine achieved a 2.4 log 10 reduction in bacterial numbers within 2 minutes, while the single-agent regimes (free chlorine alone, or copper/silver alone) showed only 1.5 & 0.03 log 10 reductions respectively. Under Staphylococcus sp challenge, the combined copper/silver and free chlorine had a faster log 10 reduction of microbial numbers than did treatment with a high level of chlorine alone.
The addition of electrolytically generated copper/silver ions in the radio tested (400 ug/liter copper to 40 ug/liter silver) allowed reduction in the concentration of free chlorine to one third of the level customarily recommended. The use of copper/silver may provide resisting protection in swimming pools after chlorine has been rendered ineffective due to contamination from swimmers and the natural environment.
Microbiological Evaluation of Copper: Silver Disinfection Units
AUTHORS: Kutz SM, Landeen LK, Yahya MT, and Gerba CP
PUBLICATION: Proceedings of the Fourth Conference on Progress in Clinical Disinfection. State University of New York, Bighamton, New York, April 11-13, 1988
PURPOSE: Although chlorination is the traditional method of disinfecting swimming pools, hot tubs, and cooling towers to prevent outbreaks of illness due to pathogenic bacteria, viruses, and protozoa, high levels of chlorine can cause eye and skin irritation was well giving rise to a noticeable chlorine odor. The authors evaluated electrolytically generated copper: silver ions alone and in combination with low levels of free chlorine as an alternative method of reducing the bacterial population in water.
MATERIALS AND METHODS:
The test medium was local well water which was subjected to chemical analysis, filtering, and pH stabilization and used at room temperature. Suspensions of the following organisms were prepared: Escherichia coli, Legionella pneumophila, Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella TYPHII, Klebsiella terrigena, and Streptococcus faecalls. Approximately 1 ml of the selected bacterial suspension was added to 99 ml of test medium containing (1) copper: silver ions in a concentration of 400 ug/liter copper to 40 ug/liter silver, (2) free chlorine (0.2 mg/liter) alone, or (3) a combination of copper: silver ions and free chlorine (quantities as above). Cultures were incubated and the bacterial colonies enumerated, after which statistical analysis were performed.
The bacteria tested were inactivated more rapidly in a solution in which electrolytically generated copper and silver ions were added to low levels of chlorine than where either method was used separately. Some organisms were more resistant to treatment than others. In the experiments with Salmonella typehi and Klebsiella terrigena no viable cells were recovered after 30 seconds of exposure to either chlorine alone or to the combined regimen, indicating equal effectiveness when resistance to disinfection is low. On the other hand, Legionella pneumophilia titers decreased more than 5 log 10 values after 7 minutes of exposure to free chlorine (0.2 mg/liters) alone for the same length of time. Similarly, E. coli numbers were reduced by 4.2 log 10 by the combination regimen but by less than 3 log 10 after extended exposure to the copper: silver method without chlorine.
The use of electrolytically generated copper and silver ions in combination with low levels of free chlorine proved an effective method of killing a wide range of pathogenic bacteria under controlled test conditions. Such bacteria are of potential concern in swimming pools and cooling towers.
Inactivation of Poliovirus & Bacteriophage MS-2 by Copper/Silver and Reduced Levels of Free Chlorine
AUTHORS: Landeen LK, Yahya MT, and Gerba CP
PUBLICATION REF: Publication information not available
PURPOSE OF STUDY:
Viruses tend to be more resistant than bacteria to disinfection regimes. Although chlorination is widely used to control viral contamination, high levels of chlorine promote the formation of organic compounds in water that may be hazardous to human health. An alternative method, copper and silver ion treatment, is known to be effective against bacteria and algae. The authors tested electrolytically generated copper and silver ions, alone and in the presence of reduced levels of free chlorine, in treating water sample to which either bacteriophage MS-2 or poliovirus had been added to test effectiveness against viral contamination.
MATERIALS AND METHODS:
Purified bacteriophage MS-2 and poliovirus type I were prepared by standard methods in pellet form. The viral pellets were placed in samples of filtered well water. The virus-containing samples were then exposed to one of the following treatment regimens: (1) no added disinfectant, i.e. untreated control; (2) low levels of free chlorine; (3) a combination of copper: silver with free chlorine; (4) copper: silver ions without chlorine; or (5) either copper or silver without chlorine. Experiments were performed in duplicate at room temperature. Linear regression analysis was performed to calculate the viral inactivation rates for each treatment regimen.
The bacteriophage MS-2 inactivation rate for copper alone was significantly higher when the concentration reached 400 ug/liter. The MS-2 inactivation rate for electrolytically generated copper and silver ions together was greater than for either metal alone, suggesting an additive effect. Although not significant for very low levels of chlorine, the addition of 0.3 mg/liter of free chlorine to a 400/40 ug/liter copper/silver regimen significantly enhanced MS-2 inactivation rates.
Similarly for poliovirus, the activation rates achieved with the 400/40 copper/silver regimen were significantly greater as compared with untreated controls. The number of poliovirus were reduced approximately 2.5 log 10 within 72 hours. The addition of 0.3 mg/liter of free chlorine again improved the inactivation rates achieved, although in this case the improvement did not reach statistical significance. Poliovirus showed greater resistance to inactivation by any means tested than did bacteriophage MS-2.
Electrolytically generated copper and silver ions demonstrate efficacy against bacteriophage MS-2; further improvement occurs with the addition of reduced levels of free chlorine. The same regimen is capable of inactivating an enteric virus such as poliovirus in the presence or absence of free chlorine. The same regimen is capable of inactivating an enteric virus such as poliovirus in the presence or absence of free chlorine. Therefore, a regimen in which copper: silver ion treatment is combined with low levels of chlorine should prove useful as a method of disinfecting water against viral contamination.
Contact: Biophysica Inc., Toronto, Ont, Canada Phone: (905) 827-9448 (10am to 10pm EST)
Copyright 2001, Biophysica Inc. All rights reserved.
This page last updated on June 24, 2007