Decontamination of Soil Contaminated with Bacillus Anthracis Spores: Technology Evaluation Report   [open pdf - 1MB]

"The U.S. Environmental Protection Agency (EPA) Office of Research and Development is striving to protect human health and the environment from adverse impacts resulting from acts of terror by investigating the effectiveness and applicability of technologies for homeland security (HS)-related applications. The purpose of this investigation was to determine the efficacy of four chemical decontaminants for inactivating 'Bacillus anthracis' (causative agent for anthrax) spores in soil. The decontaminants that were evaluated included two liquid biocides (pH-amended bleach and sodium persulfate) and two fumigants (methyl bromide and metam sodium). The objective of this study was to provide an understanding of the performance (i.e., efficacy) of these decontamination technologies to guide their use and implementation in HS applications for hard-to-decontaminate materials such as soil. In the assessment of options for decontamination following an intentional release of 'B. anthracis' spores, it is important to know what operational factors can impact the decontamination efficacy. This investigation focused on decontamination of two types of soil material: topsoil and Arizona Test Dust (AZTD). These two soil types were selected for testing in an attempt to span the range in expected organic content of soils. Decontamination efficacy tests were conducted with spores of 'B. anthracis' or 'B. subtilis', the latter microorganism included to assess its potential as a surrogate for future studies related to 'B. anthracis'. Decontamination efficacy was quantified in terms of log reduction (LR), based on the difference in the number of bacterial spores (as colony forming units) recovered from the positive controls (soil samples not exposed to decontaminant) and test samples. Tests were conducted with varying operational parameters (e.g., contact time, number of applications of the decontaminant, decontaminant concentration) to assess the effect of these parameters on decontamination efficacy."

Report Number:
Environmental Protection Agency, EPA 600/R-13/110
Public Domain
Retrieved From:
Environmental Protection Agency: http://cfpub.epa.gov/
Media Type:
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