Chap. 13. Terrorism, Toxicity, and Vulnerability 341Air is a possible medium for both chemical and biological attack. A means is required
to deliver agents through the air, which makes it difficult to expose people through this
medium. Although a low-flying crop-spraying plane would be an effective means of
spreading either chemical or biological agents through the air, it would rapidly alert
authorities leading to corrective action. Spores of bacteria that cause anthrax, Bacillus
anthracis, are of particular concern for bioterror attack through air. Other microbial
agents of concern for their potential for airborne attack include Variola major, which
causes smallpox; Francisella tularensis, which causes tularemia, and viruses that cause
viral hemorrhagic fevers, including Ebola, Marburg, Lassa, and Machupo.
Historically, the disease that has caused devastation most closely resembling the
harm that could result from a massive attack by bioagents is “plague,” which killed
tens of millions of people in Europe during the Middle Ages. This malady is caused
by infection with Yersinia pestis bacteria. This disease takes several forms, the most
common of which is bubonic plague characterized by swollen, tender lymph glands
called buboes. Readily cured by antibiotics in its early stages, it is transferred from
infected rodents to humans by fleas, and several cases are reported each year in the
Southwestern U.S. Pneumonic plague is readily spread through air between humans
and is the form of most concern for terrorist attack. Initial symptoms similar to those of
influenza progress to a fatal form of pneumonia.
13.7. Detecting Hazards
A key to protection from terrorist threats is their detection before damage can be
done. The detection of explosives immediately comes to mind. Another priority area is
detection of disease-causing pathogenic organisms.
Hazardous substances are not readily detected by standard metal detectors and X-ray
imagers used to find weapons and bombs on air travelers and in their luggage. Residues
of TNT, RDX, and PETN explosives (see Figure 13.1) can be detected by sophisticated
instruments including ion mobility spectrometers and chemiluminescence sensors. Such
instruments normally detect residues of explosives on swabs from swabbing luggage;
they can be circumvented by careful cleaning of luggage. Nuclear quadrupole resonance
(NQR) may develop as an especially promising detection technique for explosives. One
reason for this is its specificity for nitrogen, which is abundantly present in all common
explosives. Secondly, NQR has the potential to detect explosives in containers and even
land mines. It works by generating a pulse of radiofrequency radiation which excites
nitrogen atoms to higher quantized energy levels. By following the signals given off
as the atoms return to their ground energy levels the kinds and abundances of nitrogen
functional groups in explosives molecules can be determined.
“Canine olfactory detection,” as its name implies, uses the sniffing abilities of dogs,
and is widely used to detect explosives, illicit drugs, and other potentially hazardous
materials. A dog has approximately 220 million mucus-coated olfactory receptors, about
40 times the number possessed by a human, making the canine nose an extraordinarily
sensitive detector. In order for canine olfactory detection to work, a rewards system must
be used, almost always involving food. This can lead to unpredictable, temperamental