Introduction to Antimicrobial Devices
By Benjamin D. Tanner, Ph.D. - President, Antimicrobial Test Laboratories
Optional: read the official legal definition of a pesticidal device by clicking on the document. Note the highlighted section on the right - per FIFRA, EPA doesn't review data for many antimicrobial devices.
Got microbes? If you want to inactivate them and they reside on an environmental surface, here are the three main options:
Disinfectants and sanitizers - most commonly used to destroy microorganisms on environmental surfaces, but some may suffer from various drawbacks. More information about disinfectants and sanitizers here.
Antimicrobial surfaces or "treated articles" - another means of controlling microorganisms on surfaces, but not generally considered to be a quick or particularly potent means of surface decontamination. More information about antimicrobial surfaces here.
Antimicrobial devices - enable consumers to avoid some of the drawbacks associated with chemical disinfectants and generally kill microorganisms faster than antimicrobial surfaces or "treated articles." It seems there are nearly as many antimicrobial devices as there are microorganisms, but most rely on the four main technologies listed below:
- Ultraviolet Light
- Steam Vapor Disinfection
- Heat Disinfection
UV light: Ultraviolet light is a technology long used in the drinking water treatment industry for disinfection of microorganisms in water. Recently, antimicrobial devices such as UV toothbrush sanitizers and UV disinfection wands have entered the marketplace. As with chemical disinfectants, the extent of disinfection that comes about from UV treatment is a function of both the duration and intensity of treatment. As such, consumers should look for devices providing either intense treatment, long duration, or both. Additionally, consumers can request testing data from independent laboratories verifying efficacy in "real-life" settings. Note: UV water sanitizers are subject to more stringent regulation by EPA.
Steam: Steam disinfection is an established technology (think steam autoclave) that is gaining momentum with respect to disinfection of environmental surfaces. As with other antimicrobial devices, consumers should ask manufacturers to back up disinfection claims with test data from independent testing laboratories to ensure they're getting the disinfection efficacy they're promised.
Dry heat disinfection: While there are not many portable, dry heat disinfection systems on the market, potential applications exist for both disinfection of air and environmental surfaces. Such antimicrobial devices would kill microorganisms simply by heating them to a temperature at which they could not survive. One example of an existing "dry heat" device is a simple cooking oven; ovens have been used for centuries to sanitize jars for canning.
Filtration: Antimicrobial filtration devices are generally used to purify air or water. When used to remove microbial contaminants from drinking water, such devices are subject to added regulatory requirements. Filtration devices trap microorganisms in one of two major ways: The first is by adsorption, where positively charged filters are used to draw negatively charged microorganisms out of the air or water. The second is through mechanical straining, where microorganisms are simply too large to pass through the microscopic crevices of the filter. Note: it is technologically challenging to remove airborne or waterborne viruses by mechanical filtration.
Antimicrobial devices are regulated along the lines of pest control devices (think mousetrap and bug zapper). Thus, to sell an antimicrobial device in the US, manufacturers need only register their establishment and/or product with the EPA; antimicrobial efficacy and safety data are not reviewed by the Agency (though companies must keep data on file).
For consumers, it's a good idea to make sure that germ-killing claims for antimicrobial devices are supported by testing done by independent laboratories. Many manufacturers have excellent track records with respect to generating substantial and defensible bodies of data to support the disinfection claims made in conjunction with their antimicrobial devices. As a good example, consider the steam disinfection data posted online by a manufacturer of a steam disinfection device (external link).
Thanks for exploring Antimicrobial Devices at Antimicrobial Test Laboratories! Check back soon for more information and updates! This material is for educational purposes only.