Real-time warning of biological-agent attacks with the Canadian Integrated Biochemical Agent Detection System II (CIBADS II)

Abstract

The Gulf War highlighted the growing threat of military use of chemical and biological (CB) weapons. Since that time revelations about the size and scope of the offensive CB agent programs in the former Soviet Union, Iraq, and other nations have confirmed this assessment. Further, terrorist threats and incidents throughout the world in recent years have shown that there is a growing potential for the civilian use of CB weapons. Many countries have undertaken programs to develop improved defenses against CB agent use, focusing on more effective detection systems as the key to providing advanced warning of an attack or mitigating the effectiveness of an attack. Requirements for detection systems include real-time detection to provide warning in time to avoid exposure, near-real-time identification to identify agents in time to treat casualties, and collection of samples for independent verification of use to validate any response. The Canadian Integrated Biochemical Agent Detection System (CIBADS II) is the first system to combine reliable real-time detection with low support requirements and automated operation to enhance ease of deployment. A key element of the CIBADS II is the fluorescence aerodynamic particle sizer (FLAPS), which can distinguish particles that contain live organisms from most other respirable particles in air. The follow-on version of CIBADS II, called 4WARN, enhances the advantages of CIBADS II through the development of more effective alarm algorithms while reducing the size, weight, and power requirements of the system. The present article will summarize the results of over 100 releases of simulants at four sets of field trials (Dugway Proving Ground, Utah, and the Defence Research Establishment Suffield, Canada) where CIBADS II has reliably detected concentrations of simulants below 10 agent-containing particles per liter of air (ACPLA), with low false-alarm rates. It is able to discriminate releases of biological aerosols from normal background aerosols with the use of an automated alarm algorithm with an average response time of 15 s, and can avoid false alarms from fluctuations in background aerosol concentrations due to natural occurrences such as forest fires and human activity such as trucks passing by on the test site. In addition, data from the FLAPS provide previously unobtainable environmental information on the live biological content and variability in background aerosols. Our studies suggest that the background concentrations of biological particles at the sites tested can vary by over an order of magnitude, but are relatively constant as a proportion of the total background particles. These scientific data will be discussed in detail, as will the potential for use of CIBADS II and its components in the study of airborne biological organisms. © 1999 John Wiley & Sons, Inc. Field Analyt Chem Technol 3: 260–273, 1999