Train wrecks prompt chemical terror warning
Train wrecks prompt chemical terror warning
Hospitals in any area could face surge of pts
A series of hazardous substance spills and accidents on the nation's rail system has prompted the Centers for Disease Control and Prevention (CDC) to warn "of the potential for terrorist attacks on railcars carrying large quantities of hazardous substances."1 Though terrorism is not suspected in the incidents, the accidents reveal existing vulnerabilities as well as the potential for major community disruption and potential mass casualties.
To meet the threat and prevent unintentional chemical releases, the CDC called for increased collaboration among railroad stakeholder organizations (e.g., environmental, transportation, industry, public health, public safety, and research) to develop better mechanisms to monitor rail substance-release events and use available data to identify vulnerabilities and promote safer technologies and practices. "Additional preparedness measures (e.g., planning and training of local response agencies and the public and establishment of notification mechanisms, escape routes, shelter-in-place protocols, and emergency shelters) are needed to respond to hazardous-substance rail incidents," the CDC noted. Hospitals located in communities where such chemicals are regularly railed through should be aware that they could face a rapid surge of patients following an accident and release of a chemical such as chlorine.
"The biggest problem that hospitals have in responding to chlorine or a similar respiratory irritant chemical agent is the huge number of people who have potentially serious injury to their lungs all arriving in a relatively short period of time," says Eric Toner, MD, senior associate at the Center for Biosecurity at the University of Pittsburgh Medical Center. "One of the areas where we really have limited surge capacity is the area of mechanical ventilators. It would be very hard to mobilize enough ventilators in a very short period of time if we have huge numbers of people exposed to very toxic levels of these respiratory agents."
Residual chemical agents on those exposed may pose a risk of secondary spread to workers, as evidenced by pesticide patients presenting at emergency departments. Three health care workers — one who was subsequently hospitalized for nine days — fell ill after a patient who had ingested pesticide came into an emergency department in a South Georgia hospital in 2000. As a result of the case, the CDC recommended staff take personal protection measures beyond standard infection control precautions.2 Depending on the extent of the contamination, health care workers caring for chemically contaminated patients should use Level C protection (i.e., full face mask and powered/nonpowered canister/cartridge filtration respirator) or Level B protection (i.e., supplied air respirator or self-contained breathing apparatus). The type of canister/cartridge should be appropriate to the agent. If the agent cannot be identified, use an organic vapor/HEPA filter, the CDC recommended.
South Carolina disaster kills nine
Although the rate of all rail incidents has declined sharply since 1980, less improvement has been observed in recent years; the rail incident rate per million train miles actually increased from 3.76 in 2002 to 4.38 in 2004, before decreasing to 4.08 in 2005, the CDC reported. In recent years, concern over railroad safety has been elevated by major incidents such as the Graniteville, SC, train collision in January 2005 that released 11,500 gallons of chlorine gas, caused nine deaths, and resulted in 529 people seeking medical treatment, the CDC noted. In response, the U.S. Department of Transportation (DOT) and the Federal Railroad Administration launched the National Rail Safety Action Plan in 2005. The plan targets the most frequent, highest-risk causes of train incidents (e.g., equipment failure or human error) and is aimed at improving emergency preparedness and the safe handling of hazardous materials. In addition, in 2006, the DOT proposed new rules requiring rail carriers to compile annual data on hazardous materials shipments and use those data to evaluate safety and security risks and alternative routing options, the CDC reported.
Another incident occurred this year, however, underscoring that even less severe accidents can cause major disruption. On Jan. 16, a train with 12 carloads of hazardous materials or residue derailed in Brooks, KY. Tank cars containing 1,3-butadiene, cyclohexane, methyl ethyl ketone, and maleic anhydride were allowed to burn throughout the night to destroy the hazardous materials. These chemicals were detected in air and water samples from the area surrounding the incident site. Thirty-one area residents immediately reported symptoms that included headache, dizziness, upper and lower respiratory tract irritation, and eye irritation. A total of 53 people in the vicinity eventually sought medical treatment at two local hospitals, including a woman who needed two weeks of supportive therapy. In addition, 35 residents of 15 homes were prohibited from returning home for approximately six weeks until contaminated plastic water lines (penetrable by released chemicals) were replaced. Approximately 300 people from outside the evacuation area but within the path of the plume were ordered to shelter in place.
Iraq attacks use chlorine as weapon
Terrorists conducted a chemical attack on civilians in Tokyo in 1995, when 12 people were killed and 5,000 injured in the attack by the Aum Shinrykyo cult. Counterterrorism planners looking back at that attack note that it could have been considerably more deadly had the terrorists come up with a better delivery system. The inclination to use chemical materials as weapons recently has been underscored by insurgent attacks in Iraq involving chlorine-containing trucks.
"We have known since 9/11 of the threat of both weaponized chemical agents and also commercial chemical agents and the threat they pose in the hands of terrorists," Toner says. "It's actually surprising to me that the insurgents in Iraq had not done this previously. But I don't think it changes anything fundamentally for us. It's a big threat and one that has not been addressed adequately. We still see trains with toxic substances going through the middle of cities and tanker trucks on the highway. The hard question is, 'How are going to get the material where it needs to go?' There is no easy answer for that. Our economy and industry depend on these chemicals. They are essential parts of many manufacturing processes."
Every year, nearly 2 million train carloads of hazardous substances move along the rails throughout the nation, rolling into many densely populated areas in the process. Notably, about 81% of hazardous substance releases from rail events occurred in areas with residences within a quarter-mile and most of the injured were members of the general public. Of these aforementioned carloads, more than 100,000 will contain toxic inhalation hazard substances such as chlorine, anhydrous ammonia, and hydrochloric acid. Although rail events constitute only 2% of total hazardous substance releases, such incidents can cause severe public health consequences, the CDC emphasized. The scenarios ratchet up considerably when a terrorist attack is included. Consider a few cogent points drawn from a paper published last year by Lawrence M. Wein, PhD, the Paul E. Holden Professor of Management Science at Stanford University3:
- A terrorist attack on a single 90-ton chlorine tank car could generate a cloud of toxic gas that travels 20 miles. If the attack took place in a city, it could kill 100,000 people within hours. Now multiply that nightmare by another 100,000. That's the approximate number of tank cars filled with toxic gases shipped every year in the United States.
- The most dangerous chemicals are those that, on release, form heavier-than-air clouds that can travel 10 to 20 miles. The three main culprits are chlorine (used in the production of building materials), anhydrous ammonia (used for agricultural fertilizer) and, worst of all, hydrofluoric acid (used in transportation fuels).
- Chlorine and anhydrous ammonia are not stored in the vast quantities that hydrofluoric acid is at oil refineries, and the biggest threat from these chemicals may be during their transport in tank cars. To prevent these well-marked tank cars from injuring or killing tens of thousands of people, hazardous shipments must be routed away from densely populated areas.
References
- Centers for Disease Control and Prevention. Hazardous Substances Released During Rail Transit — 18 States, 2002 — 2007 MMWR 56(22); 553-556.
- Centers for Disease Control and Prevention. Nosocomial poisoning associated with emergency department treatment of organophosphate toxicity — Georgia, 2000. MMWR 2001; 49:1,156-1,158.
- Wein LM. Perspectives: Preventing Catastrophic Chemical Attacks Issues in Science and Technology. The University of Texas at Dallas; 2006.
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