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Chemical and Biological Attacks

Chapter Four
Chemical and Biological Attacks

Like nuclear and radiological attacks, the risk of a major chemical or biological terrorist attack is very low compared to the likelihood of a conventional attack. As Frank Cilluffo, a terrorism expert at the Center for Strategic and International Studies puts it: "Bugs … and gas are never going to take the place of bullets and bombs as the terrorist weapons of choice."66 The technical difficulties involved in producing and using chemical and biological weapons are significant. Most of the deadliest chemicals and microorganisms—such as anthrax spores, the smallpox virus, and the Ebola virus—are very difficult to acquire. More importantly many chemicals and microorganisms are difficult to "weaponize." They are too delicate to be scattered via explosives, and to be effective they must be dispersed in aerosol form.

The difficulty of using even the most deadly chemical weapons was demonstrated in 1995 when Aum Shinrikyo, a Japanese cult, released deadly sarin gas into a crowded subway. The Council on Foreign Relations notes that the cult "spent an estimated $30 million on chemical weapons research and had many scientists in its ranks, but it managed to kill only 19 people with the nerve agent sarin—both because it encountered problems making sarin, experts say, and because it had difficulty using it as a mass-casualty weapon."67

Nevertheless the potential consequences of a successful chemical or biological attack are so daunting that preparing for and responding to such attacks has become a major focus of homeland security efforts. An effective response can significantly reduce casualties. The worst consequences of a chemical or biological attack may be averted if first responders and the public health community are adequately prepared.

Military Chemical Weapons

Among the different types of WMD, chemical weapons are the least high tech—they require less technological expertise to develop than do nuclear or biological weapons—and therefore thought to be a likely choice for terrorists. Chemical

agents are also more readily available than biological agents. Chemical weapons basically work by dispersing poison (usually in gaseous form) into a small area.

The deadliest chemical weapons use nerve agents, which are capable of disrupting the human nervous system and paralyzing victims. Such agents do not occur in nature. They were first produced by German scientists seeking stronger pesticides in the 1930s and were later produced and stockpiled by the United States and the Soviet Union. Iraq used nerve agents in the 1980–1988 Iran-Iraq war, and the United States also suspects Syria, Egypt, Iran, Libya, and North Korea of harboring nerve gas stockpiles. Nerve gases are all colorless, odorless, tasteless liquids that vaporize into gaseous form. The two most well-known nerve gases are sarin and VX.

Sarin paralyzes the muscles of its victims and causes death by suffocation. About one liquid drop is enough to kill a person in a few minutes, but sarin dissipates very quickly in gaseous form. If administered promptly the drugs atropine and oxime can serve as an antidote to sarin. Military troops

who may face chemical warfare carry autoinjectors (syringes that inject automatically at the press of a button) of these drugs, and some cities, such as Hartford, Connecticut, and Boston, piloted projects to provide police, firefighters, and emergency personnel with nerve-agent antidote kits.

VX is the deadliest nerve agent ever created. Even small amounts absorbed through the skin can kill within minutes. The antidote for VX is similar to sarin's, but because VX acts so quickly, the antidote would need to be administered almost immediately. Both VX and sarin are difficult to produce and are believed to be beyond the means of the al-Qaeda terrorist network. A greater danger is that terrorist groups may be able to steal or purchase nerve agents from a nation's military stockpiles.

Another type of military chemical weapon that terrorists might seek to steal, purchase, or manufacture is mustard gas. First used in World War I, mustard gas is not a nerve agent and is not nearly as deadly as sarin or VX. However it is much more widely available in some Third World and eastern European countries, and it is much easier to produce than nerve agents. For these reasons some experts feel that it may be the chemical weapon of choice for terrorist groups.

Mustard gas is a blistering agent. It causes blistering of the skin, inflammation of the eyes or even blindness and, if inhaled, can cause damage to the lungs and other organs. Unlike nerve agents, exposure to mustard gas is disabling but not usually fatal, and the gas's effects are not felt immediately but instead take two to forty-eight hours to develop. There is no antidote for mustard gas. Instead treatment consists of decontaminating those exposed and using painkillers, antiburn powders, skin ointments, and other techniques to treat the injuries.

Household and Industrial Chemicals

While military-grade chemical agents make frightening chemical weapons, many homeland security officials are also concerned about more common chemicals that are widely available in the United States. As the National Research Council notes, the United States "stores, produces, and transports large quantities of toxic industrial agents. Certain of these (such as chlorine and phosgene) have actually been used as chemical weapons … others (volatile acids, certain industrial chemical intermediates) could cause numerous casualties if released in large quantities."68 In fact some homeland security officials are more concerned about the threat from common chemicals than the threat of mustard gas or nerve agents. "I just believe that at the end of the day, it's a lot easier getting something that's available here in the United States than trying to sneak in sarin,"69 says Jerry Hauer, acting assistant secretary for public health preparedness at the U.S. Department of Health and Human Services (HHS).

Chlorine and phosgene are both poisonous. The most plausible attack scenario involving these and other gases would be for terrorists to release them in an enclosed space where a large number of people gather, such as a subway station or an airport. Other concerns are that terrorists might attempt to poison food or water supplies (although the latter threat is considered unlikely, since the chemicals would be severely diluted and probably quickly discovered or neutralized through existing water treatment procedures). Terrorists could also disperse toxic agents or target large storehouses of toxic substances with conventional explosives in order to disperse hazardous substances into the environment. As journalist Guy F. Arnet writes: "Just as we could not believe that terrorists would fly airplanes into buildings, we cannot begin to think of all the ways terrorists might use chemical weapons."70

Because of the threat that hazardous chemicals pose, monitoring them has become a significant part of the overall U.S. homeland security strategy. Port and transportation authorities are monitoring chemical shipments more closely, and law enforcement agencies are working with the chemical industry to improve security at chemical facilities. At the

same time local and federal government agencies are working to prepare for the consequences of a chemical attack.

Protecting Against a Chemical Attack

The main ways to protect against chemical attack are through physical protection, medicine and antidotes, and decontamination. Physical protection consists simply of not allowing a chemical agent to come in contact with one's body. On the most basic level, this consists of getting away from, and upwind of, the hazardous agent. Physical protection may also be achieved by what the DHS calls "shielding in place"—that is, finding an enclosed room that is sealed off from the outside air. The DHS has recommended that people keep duct tape and plastic sheeting in their homes in order to seal windows and ventilation ducts in the event of a chemical attack.

Physical protection is also achieved through the use of masks that prevent the inhalation of harmful gases. To this end a simple cloth mask provides little protection but is better than nothing. Air-purifying respirators—commonly

referred to simply as gas masks—provide a higher level of protection. Full-face gas masks also protect the eyes. These types of masks are likely to be used by first responders at the scene of a WMD attack.

The best respiratory protection, however, comes from a system in which the user is not inhaling outside air at all but is breathing safe, compressed air. The best system for this is a self-contained breathing apparatus (SCBA), in which a supply of air is stored in tanks on the user's back, much like the tanks used by scuba divers. In another system the user wears a supplied-air breathing apparatus (SABA), in which the user's mask is connected to a central air supply via a long hose called an umbilical line. Because hazardous agents can be absorbed through the skin, full physical protection also requires the use of a hazmat suit.

Hazmat Teams and Decontamination

In addition to police, firefighters, and emergency medical personnel, first responders to chemical and biological attacks will also involve another group—the hazmat team. Over six hundred local and state hazmat teams—groups of hazardous-materials specialists—exist in the United States. Hazmat teams are part of any city's or state's emergency-response operations, and they deal with all types of chemical spills, injuries, and accidents. In some areas the hazmat team is part of the fire company, and many firefighters and emergency medical personnel are trained to respond to hazmat incidents. Carl Reynolds, director of the chemical industry's Chemical Transportation Center, says that America's hazmat teams "get about 150 calls a day [nationwide], all the way from a pint paint can [spill] to a major accident."71

The first task for hazmat units is to identify the harmful agent and begin providing decontamination, antidotes, and medication to victims. Antidotes and medical treatment are of little use if the harmful agent is still on the victim's person. Therefore rapid decontamination is a priority. In simple terms decontamination consists of stripping the victim of contaminated clothing and rinsing the person down with water or more specialized cleansing agents. At the scene of a WMD attack, first responders would likely set up "decon stations" for this process. All victims would need to pass through these stations before leaving the scene of the attack, since one of the greatest dangers of a WMD attack is that victims fleeing the scene could spread hazardous substances to others.

Biological Toxins

Many of the steps involved in responding to a chemical attack apply to a biological attack as well. Physical protection from the biological agent in question—via shielding in an isolated room or through gas masks and hazmat suits—would likely be the safest course of action for those in the vicinity of the attack. Hazmat teams would be called in, and decontamination would be a priority.

In fact some of the biological agents that terrorists might use as weapons act very much like chemical weapons. Ricin, a toxin that occurs naturally in the husks of castor beans (that are processed to produce castor oil) is such an agent. Because it is naturally occurring, ricin is classified as a biological rather than a chemical agent. Because castor beans are common throughout the world, it would be fairly easy for terrorists to obtain ricin. In fact ricin was found in the caves in Afghanistan in November 2001 during the search for al-Qaeda, and British antiterror squads seized a small batch in London in January 2003. From an attack-response perspective, ricin is much like a chemical weapon. The agent could be dispersed in powder or liquid form, and one milligram of ricin is enough to kill an adult. Exposure causes flulike symptoms, there is no anti-dote (although researchers are working on one), and death occurs within three to four days.

Another biological agent with properties akin to chemical weapons is botulinum toxin, a deadly substance produced by the bacterium Clostridium botulinum. It is sometimes found in undercooked or improperly canned food. Botulinum toxin is the strongest toxin known, being 1 million times stronger than sarin nerve gas. Iran, Iraq, North Korea, and Syria have developed, or are believed to be developing, botulinum toxin as a weapon, presumably to be dispersed in aerosol form. Like chemical nerve agents, botulinum toxin causes muscle paralysis and respiratory failure. It is much slower acting than nerve agents, with symptoms appearing within two to three days of exposure. If diagnosed early, victims can be treated with an antitoxin, and supportive care, which may include ventilators (breathing machines), which can sustain the patient for weeks or months while the paralysis slowly improves.


While ricin is poisonous and botulinum toxin causes paralysis, the threat more often associated with biological weapons is infectious disease—disease caused by the growth of viruses, bacteria, or other microorganisms. Anthrax, an infectious disease caused by the spore-forming bacterium Bacillus anthracis, may be contracted through the skin via cuts or abrasion, through the respiratory system via inhalation, or through the intestinal tract via ingestion of contaminated food. Depending on the path of infection, within a few days victims may experience skin bumps and ulcers, breathing problems, or vomiting and abdominal pain. Inhalation anthrax is the most deadly form of the disease. Treatment with antibiotics is usually not effective once symptoms begin (although antibiotics can be effective if the disease is caught early).

Anthrax became one of the threats most associated with bioterror in the fall of 2001 after four letters—including ones addressed to Senators Tom Daschle and Patrick Leahy, and news anchor Tom Brokaw—were found to be contaminated with anthrax spores. Twenty-three people, including eleven postal workers and eight employees of media organizations where some letters were received, contracted anthrax, and five of them died as a result.

Experts also worry that terrorists might try to disperse anthrax in more dangerous ways. Rick Weiss of the Washington Post reports that: "A little more than two pounds of anthrax spores spilled into the air over a city the size of New York could be expected to kill more than one hundred

and twenty thousand people,"72 according to computer models of terrorist acts. A vaccine exists for anthrax, but it has only been produced in limited quantities and, in order to be effective, it must be administered six times over the course of eighteen months. The U.S. military, however, does vaccinate troops that spend more than two weeks a year in high-risk areas such as the Persian Gulf.

The Threat of Contagion: Smallpox and Other Bioweapons

Although anthrax is a deadly disease, it is not contagious. It is extremely unlikely that anthrax would be transmitted from one person to another via bodily contact or a sneeze. In contrast most other bioterror threats are so menacing because they can spread from person to person. In fact the major threat of bioterrorism—what makes a biological attack different from other WMD threats—is the potential for biological agents to start an epidemic. A terrorist attack with a contagious biological agent could trigger a disease outbreak that would increase the number of casualties exponentially. Furthermore a biological attack using these agents may not be immediately obvious, since it would take days for people to become sick, during which time they might be exposing others to the agent.

Among the contagious biological threats, smallpox has received the most attention from both the media and from homeland security officials, and for good reason. As U.S. Army physician Kevin Coonan puts it: "Few diseases have rivaled smallpox as a cause of human suffering and death."73 Smallpox is extremely contagious, and like the common cold can be transmitted from person to person through the air or through contaminated clothing or surfaces. The virus causes flulike symptoms to appear within one to two weeks of infection, and then victims develop pus-filled lesions (similar to chicken-pox sores) on the face, arms, and legs. Antibiotics are not very effective in treating smallpox, and the disease is lethal in about 30 percent of cases.

Smallpox was one of the most devastating diseases until vaccination became widespread in the twentieth century. In 1979 the World Health Organization officially declared that smallpox had been eradicated through a massive, worldwide vaccination program. The United States abandoned routine smallpox vaccination in 1972 and, worldwide, no one has contracted the disease since 1978. The only known remaining strains of the virus are stored in high-security research facilities in the United States and Moscow. However, homeland security officials are concerned that other samples of the smallpox virus could still exist. The chance that terrorists could gain access to a sample of smallpox virus is remote, but if they did, the millions of Americans born since 1972 would be completely susceptible to infection. Terrorist use of smallpox is, like the use of WMD a low-probability, high-consequence threat.

In addition to smallpox the Centers for Disease Control and Prevention (CDC) has listed bubonic plague, tularemia, and hemorrhagic fevers as possible bioterror threats. Bubonic plague is the highly contagious disease that killed one-third of the population of Europe in the fourteenth century. Modern sanitation and public health practices have largely eliminated the conditions that allow Yersinia pestis, the bacterium that causes the plague, to thrive, but experts worry that terrorists might try to disperse the bacterium in aerosol form. Bioterrorism experts also fear that terrorists might try to weaponize pneumonic plague, a rarer, more lethal form of the disease. There is no vaccine for pneumonic plague, but if administered quickly, antibiotics can effectively fight both forms of the disease. Tularemia, a plague-like disease also known as rabbit fever, can also be treated with antibiotics.


As with WMD threats in general, the response to a biological attack would depend on the specific agent used in the attack. For those agents for which a vaccine exists—notably smallpox—emergency vaccination is certainly a major part of the response strategy.

The United States has over 200 million doses of smallpox vaccination, enough for every American. However, smallpox vaccination has risks. Historically between fourteen and fifty-two of every 1 million people who received the vaccine experienced life-threatening reactions, and one or two of every 1 million died. In December 2002 President Bush announced plans to vaccinate five hundred thousand health care workers, but the plan met with resistance, largely from the health care workers themselves. However, in the

case of smallpox, vaccination even three days after exposure to the smallpox virus is usually effective in stopping the disease.

Doctors, nurses, and emergency workers would still be the first to be vaccinated in the event of a smallpox or similar biological attack so that they can, in turn, vaccinate others. One strategy used in preventative vaccination is known as ring vaccination, in which contaminated individuals are identified and the people connected to them are vaccinated in an expanding circle. Federal officials announced in September 2002 that, ultimately, the discovery of even a single case of smallpox will lead to voluntary vaccinations nationwide. While vaccinations are being administered, individuals known to be infected would likely be quarantined.


Quarantines are isolation measures imposed to prevent the spread of disease. In the strictest form of quarantine, a certain area—which could range anywhere from a single building to an entire metropolitan area—is declared an infection risk, and no one is allowed into or out of that area.

Many homeland security planners are reluctant to make rigid quarantines a part of their emergency-response procedures because individuals in a possibly infectious area are likely to resist the quarantine. Abraham McLaughlin and Michelle Dent of the Christian Science Monitor report that: "Quarantine history includes serious violence. In Muncie, Indiana, in 1893, residents resisted a smallpox-induced quarantine. Violence broke out, and several officials were shot."74 Strict quarantines must be enforced to be effective, and that raises the possibility of grim scenarios that few emergency-response planners want to contemplate. For example Randall Larsen of Analytical Services Inc., known as the ANSER Institute for Homeland Security, says that with quarantines, "you have to decide whether you're going to shoot grandma in her pickup [truck] who's trying to leave the city."75

There are potentially effective, less extreme quarantine actions that could be implemented in response to a biological attack. A FEMA document explains that quarantine can involve "closing of public transportation, limiting public gatherings, and limiting intercity travel."76 Many of these protective actions are designed to limit people's contact with one another (in order to curb the spread of contagion) without resorting to a strict quarantine. Such measures were largely successful in containing the Spring 2003 outbreaks of Severe Acute Respiratory Syndrome (SARS) in China and Canada.

Strengthening the Public Health System

While the response to any type of terrorist attack will rely heavily on emergency medical personnel, an effective response to a chemical or biological attack will depend on the quality of America's public health system. In the case of a biological attack, health workers may even take the place of police and firefighters as the very first responders.

Unlike most other conceivable terrorist attacks, a biological attack might not be immediately noticeable. If agents such as the smallpox virus or anthrax spores were released discreetly, it would take days or weeks for anyone to develop symptoms. "The first sign of [a silent] attack," as bioterror researcher Rebecca Katz explains, "is likely to be the seemingly innocent event of a small number of people going to their private doctors'office or the emergency rooms of their local hospitals, complaining of flu-like symptoms."77 Once such a phenomenon is identified, medical laboratories will work to determine if a biological attack has taken place. The effectiveness of the public health system in this process is critical. The longer the attack discovery process takes, the more people will become sick or die.

To adequately respond to attack, says Katz, the nation needs "a strong infectious-disease surveillance system, vaccine development and pharmaceutical stockpiles, scientific research, communications networks, laboratory capacity,

hospital readiness, and professional training."78Many communities lack such strong public health resources, however. The Bush administration's National Strategy for Homeland Security acknowledged that: "A major act of biological terrorism would almost certainly overwhelm existing state, local, and privately owned health care capabilities."79

Despite their limited resources, hospitals across the country are doing what they can to prepare for bioterrorism. They are beefing up supplies of necessary vaccines and antibiotics, training doctors and nurses to identify and treat the major biological threats, and developing bioterror-response plans. Ultimately, however, more funding for local hospitals and other public health facilities is needed to improve America's biological and chemical attack-response capabilities. The federal government earmarked billions of dollars for hospital preparedness, bioterrorism research, and new diseasesurveillance and attack-response systems, but it will take a long time for changes to be implemented.

State and Federal Efforts

In the meantime state and federal resources are in place to help local first responders in the event of a WMD attack. For example the CDC initiated the National Pharmaceutical Stockpile (NPS) Program in 1999. The NPS is comprised of pharmaceuticals, vaccines, medical supplies, and medical equipment that might be difficult for local hospitals to obtain in the event of a major emergency. The program is capable of delivering, according to the CDC, "a complete package of medical material—to include nearly everything a state will need to respond to a broad range of threats,"80 along with a small team to assist in distribution of the materials anywhere in the nation within twelve hours.

The CDC also put together an Epidemic Intelligence Service of almost 150 professional field epidemiologists trained in detecting and investigating infectious disease outbreaks. Similarly the DHS initiated a plan to organize smallpox

response teams in each state to investigate and evaluate initial suspected cases of smallpox and initiate measures to control the outbreak.

These programs are just a few of the many attack-response and preparedness efforts managed by the federal government. The critical first response to any terrorist attack is fundamentally a local effort. But in the event of a chemical, biological, or even nuclear attack, an effective response must also involve state and federal agencies.

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