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Microbiology and Infection Information

 Safety, Toxicity

Many polluting substances are found in water:

Inorganic:  Poisonous metals and minerals eg arsenic, lead, mercury, radioactive products, herbicides, fertilizers,

Organic:  Chlorine compounds, petroleum byproducts, dioxins, hormones, antibiotics

Biofouling:  Bacteria, viruses, parasites

Microbiology in General

Electrolytically generated copper/silver ions are potently microbiocidal although somewhat slower acting than chlorine they are much less subject to degradation, having residual antimicrobial potency lasting for months. The recommended minimum level of free chlorine for disinfection of public swimming pools is 1 mg/liter (1 ppm). This level is difficult to maintain due to the chlorine-demanding organic material introduced by bathers themselves as well as the environment. Consequently the residual level of chlorine will have often dropped to 0.1 to 0.3 mg/liter after 24 hours.
Eye and skin irritation may also occur at the minimum chlorine level needed for effective disinfection.  Under Staphylococcus challenge, the combination of copper/silver together with free chlorine had a faster log 10 reduction of microbial numbers than did treatment with a high level of chlorine alone. This combination allows for a much reduced or zero level of chlorine.

Medical, Microbiology, Diseases and Infections

Anti-Microbial effects of trace quantities of metals such as Silver and Copper in trace amounts of less than 1 ppm have proven activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus anthracis, B. cereus, and B. subtilis, Vibrio cholerae, Escherichia coli, Klebsiella pneumoniae, Citrobacter freundii,  coagulase-negative staphylococci, and Enterococcus faecium, Candida albicans and C. maltosa, Legionella pneumophila, hepatitis A virus (HAV), human rotavirus (HRV), human adenovirus, and poliovirus (PV)aflatoxin production by Aspergillus parasiticus.

Silver-Containing Polymers.

Schierholz JM, Beuth J, Pulverer GKönig DP.

Antimicrob Agents Chemother. 1999 Nov; 43(11): 2819-2821.
PMCID: 89571

Silver-coated nylon fiber as an antibacterial agent.

MacKeen PC, Person S, Warner SC, Snipes W, Stevens SE Jr.

Antimicrob Agents Chemother. 1987 Jan; 31(1): 93-99.
PMCID: 174659

In Vitro Testing of Antimicrobial Activity of Bone Cement.
Alt V, Bechert T, Steinrücke P, Wagener M, Seidel P, Dingeldein E, Domann E, Schnettler R.
Antimicrob Agents Chemother. 2004 Nov; 48(11): 4084-4088.
PMCID: 525460
Silver-resistant mutants of Escherichia coli display active efflux of Ag+ and are deficient in porins.
Li XZ, Nikaido H, Williams KE.
J Bacteriol. 1997 Oct; 179(19): 6127-6132.
PMCID: 179518
Electrochemical Ag+ for preservative use.
Simonetti N, Simonetti G, Bougnol F, Scalzo M.
Appl Environ Microbiol. 1992 Dec; 58(12): 3834-3836.
PMCID: 183190
Mechanism of resistance to silver ions in Klebsiella pneumoniae.
Kaur P, Vadehra DV.
Antimicrob Agents Chemother. 1986 Jan; 29(1): 165-167.
PMCID: 180387
Use of Aqueous Silver To Enhance Inactivation of Coliphage MS-2 by UV Disinfection.
Butkus MA, Labare MP, Starke JA, Moon K, Talbot M.
Appl Environ Microbiol. 2004 May; 70(5): 2848-2853.
PMCID: 404450
Mode of Bactericidal Action of Silver Zeolite and Its Comparison with That of Silver Nitrate.
Matsumura Y, Yoshikata K, Kunisaki SI, Tsuchido T.
Appl Environ Microbiol. 2003 Jul; 69(7): 4278-4281.
PMCID: 165194
Negative Effect of High pH on Biocidal Efficacy of Copper and Silver Ions in Controlling Legionella pneumophila.
Lin YS, Vidic RD, Stout JE, Yu VL.
Appl Environ Microbiol. 2002 Jun; 68(6): 2711-2715.
PMCID: 123931
Effects of Halides on Plasmid-Mediated Silver Resistance in Escherichia coli.
Gupta A, Maynes M, Silver S.
Appl Environ Microbiol. 1998 Dec; 64(12): 5042-5045.
PMCID: 90966
Role of a Candida albicans P1-Type ATPase in Resistance to Copper and Silver Ion Toxicity.
Riggle PJ, Kumamoto CA.
J Bacteriol. 2000 Sep; 182(17): 4899-4905.
PMCID: 111370
Broad-Spectrum Bactericidal Activity of Ag2O-Doped Bioactive Glass.
Bellantone M, Williams HD, Hench LL.
Antimicrob Agents Chemother. 2002 Jun; 46(6): 1940-1945.
PMCID: 127232
Microbicidal Activity of a New Silver-Containing Polymer, SPI-ARGENT II.
Kampf G, Dietze B, Große-Siestrup C, Wendt C, Martiny H.
Antimicrob Agents Chemother. 1998 Sep; 42(9): 2440-2442.
PMCID: 105850
Inactivation of Vegetative Cells, but Not Spores, of Bacillus anthracis, B. cereus, and B. subtilis on Stainless Steel Surfaces Coated with an Antimicrobial Silver- and Zinc-Containing Zeolite Formulation.
Galeano B, Korff E, Nicholson WL.
Appl Environ Microbiol. 2003 Jul; 69(7): 4329-4331.
PMCID: 165132
Silver-based crystalline nanoparticles, microbially fabricated.
Klaus T, Joerger R, Olsson E, Granqvist CG.
Proc Natl Acad Sci U S A. 1999 Nov 23; 96(24): 13611-13614.
PMCID: 24112
Chemiosmotic Mechanism of Antimicrobial Activity of Ag+ in Vibrio cholerae.
Dibrov P, Dzioba J, Gosink KK, Häse CC.
Antimicrob Agents Chemother. 2002 Aug; 46(8): 2668-2670.
PMCID: 127333
Activities of a Nitrofurazone-Containing Urinary Catheter and a Silver Hydrogel Catheter against Multidrug-Resistant Bacteria Characteristic of Catheter-Associated Urinary Tract Infection.
Johnson JR, Delavari P, Azar M.
Antimicrob Agents Chemother. 1999 Dec; 43(12): 2990-2995.
PMCID: 89599
Toxic Effects of Ag(I) and Hg(II) on Candida albicans and C. maltosa: a Flow Cytometric Evaluation.
Zhang S, Crow SA Jr.
Appl Environ Microbiol. 2001 Sep; 67(9): 4030-4035.
PMCID: 93125
Inactivation of Treponema pallidum by Silver Sulfadiazine.
Chang TW, Weinstein L.
Antimicrob Agents Chemother. 1975 May; 7(5): 538-539.
PMCID: 429178
Efficacy of copper and silver ions and reduced levels of free chlorine in inactivation of Legionella pneumophila.
Landeen LK, Yahya MT, Gerba CP.
Appl Environ Microbiol. 1989 Dec; 55(12): 3045-3050.
PMCID: 203221
Disinfection of human enteric viruses in water by copper and silver in combination with low levels of chlorine.
Abad FX, Pintó RM, Diez JM, Bosch A.
Appl Environ Microbiol. 1994 Jul; 60(7): 2377-2383.
PMCID: 201659
Comparison of four methods for rapid detection of Pneumocystis carinii in respiratory specimens.
Cregan P, Yamamoto A, Lum A, VanDerHeide T, MacDonald M, Pulliam L.
J Clin Microbiol. 1990 Nov; 28(11): 2432-2436.
PMCID: 268201
Silver-nylon: a new antimicrobial agent.
Deitch EA, Marino AA, Gillespie TE, Albright JA.
Antimicrob Agents Chemother. 1983 Mar; 23(3): 356-359.
PMCID: 184651
Plasmid-determined silver resistance in Pseudomonas stutzeri isolated from a silver mine.
Haefeli C, Franklin C, Hardy K.
J Bacteriol. 1984 Apr; 158(1): 389-392.
PMCID: 215434
Bacterial sorption of heavy metals.
Mullen MD, Wolf DC, Ferris FG, Beveridge TJ, Flemming CA, Bailey GW.
Appl Environ Microbiol. 1989 Dec; 55(12): 3143-3149.
PMCID: 203237
Comparative Poliovirus Permeability of Silver, Polycarbonate, and Cellulose Membrane Filters.
Hahn RG, Hatlen JB, Kenny GE.
Appl Microbiol. 1970 Feb; 19(2): 317-320.
PMCID: 376675
The infrared spectrum and structure of the type I complex of silver and DNA.
DiRico DE Jr, Keller PB, Hartman KA.
Nucleic Acids Res. 1985 Jan 11; 13(1): 251-260.
PMCID: 340988
Effects of activated carbon and bacteriostatic filters on microbiological quality of drinking water.
Tobin RS, Smith DK, Lindsay JA.
Appl Environ Microbiol. 1981 Mar; 41(3): 646-651.
PMCID: 243753
Susceptibility of Bacteroides spp. to heavy metals.
Riley TV, Mee BJ.
Antimicrob Agents Chemother. 1982 Nov; 22(5): 889-892.
PMCID: 185676
Rapid presumptive bacteriological diagnosis of Legionnaires disease.
Faine S, Edelstein P, Kirby BD, Finegold SM.
J Clin Microbiol. 1979 Jul; 10(1): 104-105.
PMCID: 273102
Reversal of the silver inhibition of microorganisms by agar.
Tilton RC, Rosenberg B.
Appl Environ Microbiol. 1978 Jun; 35(6): 1116-1120.
PMCID: 242993
Electrically Generated Silver Ions: Quantitative Effects on Bacterial and Mammalian Cells.
Berger TJ, Spadaro JA, Chapin SE, Becker RO.
Antimicrob Agents Chemother. 1976 Feb; 9(2): 357-358.
PMCID: 429529
Properties of Silver Sulfadiazine-Resistant Enterobacter cloacae.
Rosenkranz HS, Coward JE, Wlodkowski TJ, Carr HS.
Antimicrob Agents Chemother. 1974 Feb; 5(2): 199-201.
PMCID: 428945
Prevention of Herpes Keratoconjunctivitis in Rabbits By Silver Sulfadiazine.
Chang TW, Weinstein L.
Antimicrob Agents Chemother. 1975 Dec; 8(6): 677-678.
PMCID: 429446
Effects of Trace Metals on the Production of Aflatoxins by Aspergillus parasiticus.
Marsh PB, Simpson ME, Trucksess MW.
Appl Microbiol. 1975 Jul; 30(1): 52-57.
PMCID: 187113
Silver Sulfadiazine: Effect on the Ultrastructure of Pseudomonas aeruginosa.
Coward JE, Carr HS, Rosenkranz HS.
Antimicrob Agents Chemother. 1973 May; 3(5): 621-624.
PMCID: 444467
Silver Sulfadiazine: In Vitro Antibacterial Activity.
Carr HS, Wlodkowski TJ, Rosenkranz HS.
Antimicrob Agents Chemother. 1973 Nov; 4(5): 585-587.
PMCID: 444599
Comparison of Methods for the Recovery of Virus Inoculated into Ground Beef.
Tierney JT, Sullivan R, Larkin EP, Peeler JT.
Appl Microbiol. 1973 Oct; 26(4): 497-501.
PMCID: 379834
Silver Sulfadiazine: Effect on the Growth and Metabolism of Bacteria.
Rosenkranz HS, Carr HS.
Antimicrob Agents Chemother. 1972 Nov; 2(5): 367-372.
PMCID: 444322