Destruction Efficiency of Microbiological Organisms in Medical Waste Incinerators: a Review of Available Data

After a building has undergone a terrorist attack using a biological weapon such as B. Anthracis, many of the interior building materials will need to be disposed. Although it is likely that these materials will be decontaminated prior to their removal, officials may decide to remove the potentially bio-contaminated materials without first fumigating them. In either scenario, the possibility exists that some of the building materials will retain viable contaminating agent spores. Incineration may be the best option for the disposal of such building materials to completely destroy all potentially remaining bio-contaminants. In the early 1990s, the US Environmental Protection Agency (EPA) conducted microbial survivability tests at several medical waste incinerators (MWIs); these data have now been examined to evaluate microbiological destruction performance. Microorganisms were spiked into the waste feed and in test pipes, and subsequently analyzed for viability in the emissions, residue, and pipes using EPA conditional test methods. The results showed that for the most of the test runs, at least a five log reduction of the spores was achieved, although viable spores were detected in 10 out of a total of 48 air emission test runs, and spores were detected in 10 out of 27 available ash samples.