guiding clean-up after an attack with spore-forming agents like anthrax that can survive in the environment for years). This is far different from the battlefield scenario of military units facing an enemy with an arsenal of identified biological weapons. Monitoring the environment for those agents and providing these at-risk troops with the means to rapidly identify contaminated air, water, food, and equipment would literally be vitally important. To the extent that similar high-risk situations can be identified in the civilian environment (the President's State-of-the-Union Address? The Superbowl? A soggy package labeled "anthrax"?), there may be a civilian need for monitoring and detector technology as well. For this reason, although the committee does not believe these situations will be frequent enough to merit a major investment for civilian use, the chapter concludes by summarizing current R&D efforts on environmental detection by military and other laboratories.
The classical approach to microbial detection involves the use of differential metabolic assays (monitored colormetrically) to determine species type in the case of most bacteria, or the use of cell culture and electron microscopy to diagnose viruses and some bacteria that are intracellular parasites. Samples taken from the environment, such as soil and water, and most clinical samples must be cultured in order to obtain sufficient numbers of various cell types for reliable identification. The time required for microbial outgrowth is typically 4–48 hrs (or two weeks for certain cases, such as Mycobacterium tuberculosis). Furthermore, bacterial culture suffers from an inherent drawback: cells that are viable may not be culturable, because they possess unanticipated nutritional requirements as a result of genetic mutation. The following few pages lay out some general approaches being taken to eliminate these drawbacks of the traditional methods and provide some examples of efforts to apply them to detection of potential biological weapons. Biodetection is a very large and active field which merits a study all by itself, and for that reason the rest of the chapter is deliberately confined to technologies and research that has focused on the agents of central concern to this report. The interested reader is referred to any or all of the following general reviews: Turner et al. (1987), Janata (1989), Wolfbeis (1991), Taylor and Schultz (1995), Van Emon et al. (1996), Rogers et al. (1995), Kress-Rogers (1997). Boyle and Laughlin (1995) provide a history of the U.S. military biodetection program, and Boiarski et al. (1995) described a large number of biodetection technologies being explored by the U.S. military at that time.
In summarizing the current review, it is convenient to consider detection