Controlling Microbial Growth

This article compares three established technologies used for over 20 years in the healthcare environment, to control microbial growth. These preservatives are used to protect the treated articles and include metal-based, triclosan-based and silane-based technologies. All three technologies are used with a standard cleaning protocol.

Metal-based technologies, in its simplest form, use a coating system formed by binding ions (ex: silver) to a fine ceramic powder. Trade examples of this technology include Alphasan, Fossshield and X-Static. This technology is found as a treatment of HVAC, floors, walls, lockers, safety cabinets, bedpans, soap dispensers, and medical devices.

For metal-based technologies to work, they must leach. This mode of action releases ionic free radicals that react with cell DNA and disrupts critical life processes in the cell. Since this mode of action leaches, adaptive zones have been created which can cause resistant species. We found metal-based technologies are harvested through mining and therefore can be costly to manufacture.

Unlike silver-based, triclosan-based technologies are created by adding, blending, melting, molding, or extruding a biocide into the final article. Trade examples of embedding or surface applying trioclosan-based technologies include Amicor, Microban and UltraFresh. You can find this treatment is used on bed frames, handrails, door handles, and linens.

Triclosan-based technologies also leach for their mode of action. This mode of action releases toxic polychlorinated biphenlys (PCB) for cellular absorption, which can cause lethal mutations in cells. Recent laboratory studies have shown that Triclosan does alter hormone levels in test animals. In July, the EPA announced that the result of these recent studies does merit further review and the EPA would begin a safety review of this technology.

Silane-based technologies permanently bond to any surface that contains oxygen, nitrogen, or carbon with Silicon as the bonding agent. This application is a surface application that does not affect the original physical properties of the treated article. It is odorless and colorless technology that attracts microorganisms with its ionic charge and physically destabilizes cell membrane on contact through a physical control and not a chemical control. This technology is found on hospital garments, wound dressings, stents, catheters, bandages, stocks, building materials and now casework.

Although all three technologies would help protect our casework, in July 2010, Case Systems made the decision to offer our casework treated with, ÆGIS Microbe Shield® technology, a silane-based technology. With a permanent bond to the surface material, ÆGIS Microbe Shield® technology does not off gas, leach or migrate into the environment. Originally developed by Dow Corning Corporation, the material preservative technology is EPA registered with 30 years of safe and effective use, controls microbial growth without the use of heavy metals, silver or poisons, is effective against a wide range of microorganisms, including bacteria and fungi (mold and mildew) and is laboratory proven not to promote an environment for adaptive organisms.

About the Author:

Kevin Krenzke is the Regional Sales Manager for Case Systems, a manufacturer of quality, adaptable, and aesthetically pleasing Divisions 12 (Manufactured Casework), 11 (Plastic Laminate Casework) and 6 (Architectural Millwork) products. For three years, Kevin has assisted Case Systems in actively researching these technologies to determine which technology adds an extra layer of protection for storage and work surface solutions from bacteria and other microbes that can cause staining, deterioration and odors for healthcare, education and laboratory settings. Contact Kevin Krenke at 989-496-0451 or via email at kevin.krenzke@casesystems.com.