ENCYCLOPEDIA OF Espionage, Intelligence, and Security Volume ...

Chemical and Biological Detection TechnologiesA technician collects a sample from a laptop computer that will beanalyzed by the Sabre 2000 trace detection instrument, which can detecttraces of explosives, drugs, or chemical weapons. AP/WIDE WORLD PHOTOS.❚ BRIAN HOYLEChemical and BiologicalDetection TechnologiesThe ability to detect the components of chemical andbiological weapons is an important part of a nationalsecurity strategy. For example, the inability to rapidlydetect letters for the presence of anthrax spores provideda route for the targeting of infectious microorganisms inthe United States in 2001. The portability of chemical andbiological weapons has made them attractive to individualsor groups with political, religious, or other grievances.This has spurred development of more sophisticated,accurate and rapid detection technologies.The conventional x-ray technology long used in airportshas been refined. Most of the x-ray beam is reflectedback immediately upon encountering an object. Some ofthe radiation, however, passes through the object. Byanalyzing the beams that actually penetrate through anEncyclopedia of Espionage, Intelligence, and Securityobject, information on the object’s composition is provided.Another version sends two different x rays of differentwavelengths through an object. The different beamscan distinguish between organic objects, such as food andpaper, and inorganic objects.A chemical detection technology known as gas chromatographyhas been sped into routine use in airportssince the U.S. terrorist attacks of September 11, 2001. Thedifferent chemicals present on a cloth that is swiped overan object can be separated based on their different preferencefor the gas mixture that is pumped through thesample chamber. A target chemical (i.e., an explosive) isdetected within seconds.Chemical detection technologies have also beenadapted for use “in the field”, such as by United Nationsinspectors deployed in Iraq beginning in November 2002,to the presence of missiles that were supposedly destroyedby the Iraqi government in the mid-1990s.Sound can be used to detect chemicals. For example,the acoustic wave sensor uses a quartz surface to convertincoming sound waves into electrical signals. Over a dozendifferent chemicals can be detected within seconds, evenfrom biological sources. In another sound-based techniquecalled acoustic resonance, the pattern of vibrationswhen sound waves are sent inside an object like a missilecan reveal whether the missile is filled with a solid or aliquid, and even the type of chemical present.Light is another means of chemical detection. The useof light is called spectroscopy. Mass spectroscopy determinesthe mass of proteins, which is important in determiningthe identity of the chemical or biological agent.Matrix-Assisted Laser Desorption/Ionization Mass Spectroscopy(MALDI-MS) can identify proteins that are uniqueto Bacillus anthracis (the cause of anthrax) and Yersiniapestis (the cause of plague). Raman spectroscopy measuresthe change in the wavelength of a light beam by thesample molecules. Optical spectroscopy measures theabsorption of light by the chemical groups and the subsequentemission of light by the same groups as the identificationmethod.The ability to detect genetic sequences that are uniqueto certain bacteria (gene probing) has been exploited todevelop genetically based microbial detection methods.The best example of gene probing is the polymerase chainreaction (PCR), which can enzymatically detect a targetstretch of genetic material and rapidly amplify that regionto detectable levels. Handheld PCR detectors (i.e., HandheldAdvanced Nucleic Acid Analyzer, or HANAA) were used inthe 2002–2003 inspections of Iraqi facilities by UnitedNations officials.Biological detection devices can monitor the surroundingair at regular intervals. Air is automatically drawninto the device and analyzed for target genetic sequencesusing the PCR technology. The results can be electronicallyrelayed to a central base for analysis.Another biological technology utilizes antibodies thatare produced in response to the presence of a specific175