Methods and Guidance for Testing the Efficacy of Antimicrobials against Biofilm Bacteria on Hard, Non-Porous Surfaces
For Release: August 1, 2017
EPA is announcing the availability of two test methods (MB-19 and MB-20) for evaluating the efficacy of antimicrobial pesticides against two biofilm bacteria, Pseudomonas aeruginosa and Staphylococcus aureus, as well as regulatory guidance for pesticidal claims for those products. These test methods and guidance provide a framework for registrants who seek to make a claim for antimicrobial pesticide products to control these bacteria on hard, non-porous surfaces.
Under the Federal Insecticide, Fungicide, and Rodenticide Act, the registrant of an antimicrobial product with a public health claim is required to submit efficacy data to EPA in support of the product's registration.
Bacterial biofilms excrete a slimy, glue-like substance (extracellular polymeric substances, called the biofilm matrix) that facilitates attachment to many hard surfaces such as glass, metals, and plastics, which are commonly found in health-care settings. The substance embeds bacteria with protection from dehydration and other environmental stresses, and can interfere with the action of chemical disinfectants.
EPA solicited comments on the clarity of the test methods and the regulatory guidance in October 2016. The agency is also working with ASTM International, a standard-setting organization, on adoption of these test methods as official ASTM standards