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Two Proposed Test Methods and Guidance for Antimicrobial Efficacy Testing

For Release: October 4, 2016

Updated October 28, 2016:  The comment period has been extended to January 21, 2017.

EPA is announcing the availability for public comment of two proposed test methods and associated testing guidance for evaluating antimicrobial pesticides against two biofilm bacteria, Pseudomonas aeruginosa and Staphylococcus aureus.

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, including those in health-care settings. The biofilm matrix provides embedded bacteria with protection from dehydration and other environmental stresses, and interferes with the action of chemical disinfectants.

Under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), 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.

More information about types of antimicrobial products.

EPA is soliciting comments on the clarity of the standard operating procedures and the regulatory guidance. Comments will be collected for 60 days (until December 5, 2016), at which point EPA will finalize the procedures and provide the revised methods for use. The methods, guidance and additional background documents are available in dockets EPA-HQ-OPP-2016-0357 at