Comparative sporicidal effects of disinfectants after release of a biological agent.

Because of spore formation, Bacillus anthracis is considered the most resistant biological warfare agent known. The present study aimed to assess and compare well-known decontamination routes to inactivate the spores on daily-use environmental tools contaminated previously. To simulate the agent, Bacillus atrophaeus was used. Various environmental samples (such as tile, fabric clothing, wood, protective suit, glass, paper, soil, water, plastic, and metal) that may be contaminated after a biological incident were used as test carriers and inoculated with B. atrophaeus. Sodium hypochlorite, free chlorine, autoclaving, ethylene oxide, hydrogen peroxide, ultraviolet irradiation, and boiling decontaminated the samples. Glutaraldehyde (2%) and free chlorine solution (10,000 mg/L) were also found to be effective in decontaminating the samples and are recommended as alternatives to the use of sodium hypochlorite solution. Soil, tile, paper, and metal were determined to be the most difficult materials to decontaminate. It was concluded that 5% hypochlorite adjusted with acetic acid might also be used for decontamination. Decontamination strategies to reduce contamination of the environment by biological warfare agents need to be applied to mitigate the number of victims, in terms of prominent characteristics like cost-effectiveness and user-friendliness.