Microchem Laboratory is a leader in the testing of antimicrobial fabric and textile products. The laboratory understands federal and state antimicrobial product regulations and works with clients to rapidly and cost-effectively bring new products to market. In addition, Microchem can help identify opportunities for existing antimicrobial fabrics and textiles.
Introduction to the Regulation and Testing of Antimicrobial Fabrics and Textiles in the United States.
The majority of antimicrobial textiles sold in the United States utilize EPA-registered active ingredients and restrict claims to “object protection” and odor control rather than health protection. By doing so, the products comply with EPA’s Pesticide Registration Notice 2000-1, also known as the Treated Article Exemption. Companies that comply with the treated article exemption are not required to submit efficacy data to EPA before marketing products and are free to conducting with test methods they prefer. Most treated articles rely on silver ions or silane quats.
The test methods ordinarily used to test antimicrobial surface efficacy are exceptionally sensitive to antimicrobial activity. Even low-level antimicrobial properties are readily detected by methods such as ISO 22196 and ASTM E2149.
The drawback of many of the popular antimicrobial surface testing methods is that they do not reflect exposures to microorganisms in realistic settings. For example, for ASTM E2149, antmicrobial surfaces are submerged in inoculated water and then shaken vigorously for an hour, sometimes 24 hours. For ISO 22196, evaporation of the dilute inoculum is prevented by covering it with plastic. For both of those popular tests, the water in the test system dramatically enhances the reaction between embedded antimicrobial agents and microorganisms. In actual use, most antimicrobial surfaces are not covered with water for more than a few minutes. A great example is contaminated droplets from a sneeze. Initially the microorganisms are in contact with the antimicrobial surface and water, but after a few minutes the microorganisms dry to a film.
Ideally, antimicrobial surfaces exert effects rapidly over brief periods of time, or at a slower pace but on dry microbial films. For companies with promising technologies, registration of the antimicrobial surface as a pesticide may be worthwhile. The test methods required are more realistic and challenging to pass, but the rewards of being able to make so-called “health claims” in commerce are great. Thus far, only select copper-containing surfaces have been registered as antimicrobial surfaces with health claims.
Antimicrobial Textile and Fabric Test Methods
The methods listed below are the some of the most commonly requested by our clients. If you have questions about the methods below and which is the best suited for you and your technology, contact the lab to speak with a scientist.
- AATCC 100 (Test for Antimicrobial Fabrics)
- JIS L 1902 (Japanese Standard Test for Antimicrobial Textiles)
- ISO 20743 (Determination of Antibacterial Activity of Textile Products)
- ASTM E2149 (“Shake Flask” Test for Antimicrobial Surfaces and Textiles)
- AATCC 147 (Antimicrobial Fabric Zone of Inhibition Test)
- ASTM E2180 (Standard test Method for Determining the Activity of Incoporated Antimicrobial Agents in Polymeric or Hydrophobic Materials)
About Antimicrobial Fabric Testing
Most fabric odors are created when microorganisms transform normal components of sweat to odiferous compounds. As a result, antimicrobial treatment of textiles confers real, observable benefits to consumers by controlling odors. In fact, certain antimicrobial sports apparel can be worn serveral days in a row before odor emerges. Antimicrobial additives also provide benefits to socks, undergarments, and outdoor gear that is frequently exposed to water.
Since odor prevention on fabrics relies on inhibition of growth rather than on killing microorganisms, it is appropriate to utilize sensitive antimicrobial test methods. AATCC 100 and ISO 20743 are most popular. In the laboratory’s experience, products that demonstrate consistent performance in these methods prove resistant to odors during ordinary use.
Some antimicrobial technologies are resistant to laundering, while others are not. Microchem can help your company to assess levels of antimicrobial activity before and after laundering.