In espionage novels, cyanide capsules are swallowed by captured spies who would rather commit suicide than divulge classified information. But the highly toxic chemical used in so many works of fiction is a real threat for being used as a terrorist weapon.
Air Force Maj. (Dr.) Vik Bebarta, a physician and medical toxicology specialist, outlined the real-life concerns about cyanide during a Sept. 2 webcast of "Armed with Science: Research and Applications for the Modern Military" on Pentagon Web Radio.
"It was [possibly] used in the first World Trade Center bombing in 1993, which many people were not aware of," Bebarta said. "It was used in the sarin nerve gas bombing [in Tokyo] in 1995; and in the last two years, there have been four foiled plots in Europe and a couple of domestic plots also that have been foiled."
Aside from terrorist attacks, exposure to cyanide may come from inhaling smoke from burning plastics during industrial or home fires. Swallowing or breathing even a small amount of cyanide, from 200 to 300 milligrams, is all it takes to become ill, Bebarta said. Toxic effects include severe sedation, lower blood pressure and acid buildup in the blood.
That is why Bebarta, chief of medical toxicology at Wilford Hall Medical Center, Lackland Air Force Base, Texas, and assistant professor of emergency medicine at the University of Texas Health Sciences Center at San Antonio, sees a need for better tools to diagnose and treat acute cyanide toxicity in critically ill patients, such as those stricken in a terrorist attack.
During a year-long study, Bebarta and his colleagues tested the standard, 50–year-old drug treatment against a newer medication made with the metal cobalt.
"We conducted an experiment comparing the old antidote kit with the new one and looking at a very critically ill [lab animal] model. Comparing blood pressure and other parameters, [we saw] that there's a difference," Bebarta said.
That difference showed better results using the newer antidote to raise blood pressure and eliminate all cyanide from the blood.
In May, the comparison study received the Best Basic Science Research Award from the Society of Academic Emergency Medicine. Bebarta is especially honored, he said, because, "typically, these awards go to civilian and [National Institute of Health]- funded researchers."
Bebarta now is looking for ways to use biomarkers to more easily diagnose cyanide poisoning. "In the last 10 years or so, this field's exploded with technology," he said. "And [scientists are] able to measure thousands of proteins in the blood and measure three or four proteins together as a pattern. If that pattern of proteins is present, then that disease is present or that illness is present."
In addition to improved diagnostic tools, Bebarta said, he hopes to develop cyanide antidotes that can be given in pill form or injected directly into muscles instead of intravenously, "because when you have a big exposure, for example, a large building that catches on fire, [or a terrorist event] and you need to treat several patients in the field or in an ambulance, you need something that a paramedic can give quickly to several patients -- and putting in an IV [vein catheter] for all these patients is not feasible."
In the future, Bebarta said, he would like to conduct research to determine which treatments for cyanide toxicity support the best long-term neurological outcomes for patients.
(Author Judith Snyderman works for the Defense Media Activity's emerging media directorate.)
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