Disinfectant testing in the USA

The federally mandated registration of disinfectants with the United States Environmental Protection Agency (EPA) requires the submission of efficacy test data obtained with the accepted methods of the Association of Official Analytical Chemists (AOAC). These include qualitative suspension tests for bacteria and fungi and carrier tests with use-dilutions for bactericidal, mycobactericidal and sporicidal activity. There is no AOAC method for virucides, and the present methods set forth by the American Society for Testing and Materials (ASTM) and the EPA are under scrutiny by the scientific community. The AOAC use-dilution test was challenged by the users, and two collaborative studies by the EPA and the AOAC did not resolve all questions. A new, quantitative supension test was proposed. The AOAC mycobactericial carrier test was found to be deficient for testing glutaraldehydes; an updated version and a new quantitative suspension test have been accepted by the EPA for registration. As a result, different glutaraldehyde preparations carry different label claims which are confusing to the consumer. National and international standardization of testing is desirable.