Decontamination of Materials Contaminated with Spores of Bacillus anthracis Ames and Vollum Strains Using Low Levels of Hydrogen Peroxide Vapor
Citation:
Richter, W. AND Joe Wood. Decontamination of Materials Contaminated with Spores of Bacillus anthracis Ames and Vollum Strains Using Low Levels of Hydrogen Peroxide Vapor. U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-18/215, 2018.
Impact/Purpose:
In the decontamination of buildings contaminated with Bacillus anthracis (Ba) spores using fumigation techniques, it may be challenging to reach the desired gas concentration without specialized equipment, modifications, or expertise. Thus, in this study, the decontamination efficacy of low levels of hydrogen peroxide vapor (HPV) was evaluated on common building materials (glass, bare pine wood, carpet, painted wallboard paper, unpainted concrete, and ceiling tile) contaminated with Ba spores. All testing was conducted using both Ba Ames and Vollum strains concurrently to allow for direct comparison of the two strains. Decontamination efficacy was quantified based on the log10 reduction (LR) in viable spores, calculated from difference in spores recovered from positive controls and test materials. Major Findings Low levels of HPV (e.g., 10-50 parts per million (ppm)) were effective in decontaminating all materials tested in the study except for unpainted concrete. Moreover, the glass, ceiling tile and painted wallboard paper materials were more amenable to decontamination by low levels of HPV compared to unpainted concrete, carpet, and wood. Even with using extended contact times (and hence higher dosages of HPV), the number of occurrences in which unpainted concrete, carpet, and wood were successfully decontaminated (complete inactivation of spore population or ≥6 log reduction) in the study was much less than the glass, ceiling tile, and painted wallboard materials. Nevertheless, there were in fact several instances when the carpet and wood materials were successfully decontaminated. Thus, fumigating at relatively low levels may allow for less experienced contractors to provide decontamination services with less specialized equipment. This advantage may be critical to increasing the nation’s decontamination capacity in the event of a wide area release of Ba spores.
Description:
Report on the decontamination efficacy of low levels of hydrogen peroxide vapor (HPV) was evaluated on common building materials (glass, bare pine wood, carpet, painted wallboard paper, unpainted concrete, and ceiling tile) contaminated with Ba spores.