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DRUGS IN WORKS TO FIGHT DIRTY BOMBS
The disclosure of an anti-radiation compound under development at the University of Chicago comes on the heels of other recent scientific advances designed to defang biological and radiological terrorist weapons. The federal government has placed a rush order with drug companies to make a safer smallpox vaccine in quantities to protect every U.S. resident. And researchers have discovered that early anthrax infections can be successfully treated with antibiotics. Drugs are also being developed to neutralize anthrax toxin before it can kill in late stages of infection. The dirty bomb threat appeared to become more real Monday when the Justice Department announced the arrest of a former Chicago street gang member in an alleged plot to detonate one in Washington. Dirty bombs are not atomic bombs. Dynamite or other explosives are used to pulverize a radioactive source into the air. Relatively few deaths are likely to occur from a radioactive device, and most radiation would be confined to a local area. But the value to terrorists is in causing widespread fear of radiation poisoning. One of the drugs to combat radiation exposure has been approved for use to protect a patient's salivary glands while undergoing cobalt treatment for head and neck cancer. Low doses of the same drug, amifostine, protect animals from potential cancer-causing mutations when given up to three hours after radiation exposure, said Dr. David J. Grdina, professor of radiation and cellular oncology at the University of Chicago. "It means that if you have individuals who are guarding or working in these areas, or performing emergency care, that they could get an enhancement in their radio-protective capability for anywhere from one to three days," Grdina said. The biggest worry from the kind of radiation that would be produced by a dirty bomb is possible long-term genetic mutations that could lead to cancer or other diseases. Massive doses of radiation, such as those from a nuclear blast, quickly destroy blood cells and internal organs and cause death in 5 to 30 days. Both the dirty bomb and a nuclear weapon can make materials such as iodine and calcium radioactive. Iodine is particularly dangerous because it collects in the thyroid gland and can cause cancer. The Nuclear Regulatory Commission is stockpiling millions of potassium iodide pills to prevent thyroid cancer from radioactive iodine. But those pills would not be effective if a different radioactive material were used in a dirty bomb. Additional compounds, called chelating agents, are available to remove other radioactive molecules from the body. Scientists have not worked out how the new anti-radiation drugs could be distributed quickly enough to thousands of people to be effective. At this point they are injected, which means hospitals and other emergency-care providers already would have to be equipped with the drugs. The most serious threat from a dirty bomb or nuclear device comes from gamma radiation, which can penetrate metal and cause genetic damage. In an effort to protect soldiers from this radiation, the Army established a drug program in 1983 at Argonne National Laboratory near Lemont to protect soldiers at some distance from a direct blast. Amifostine was developed at that time, and tests showed it would protect soldiers so they could still fight. But the army lost interest when it learned the drug had to be given at least 30 minutes before radiation exposure and that the high dose needed would make soldiers too nauseated to fight. Grdina, who worked on the compound at Argonne discovered that low doses in animals that did not cause nausea could provide protection against radiation damage when given up to three hours after exposure. "The drug not only has the ability by itself to reverse the radiation damage that causes mutations, but it also causes the cells in your body to start producing your inherent radio-protective enzymes," he said. Grdina reported the amifostine findings at a recent meeting of the American Association of Cancer Research. Construction has begun in Argentina on the world's biggest cosmic ray observatory. Its telescopes will scour the heavens for clues which may solve mysteries surrounding the Big Bang, black holes and sub-atomic particles. Cosmic rays are super-fast protons and have the highest energy levels of any known particle in the Universe. But the source of the most energetic of these particles is "a complete mystery", according to Nobel prize winner Dr James Cronin. He is co-director of the Auger Project and a physics professor at the University of Chicago. The Argentine government will put $15 million toward the expected $50 million cost of building the observatory. The array of telescopes, sited 1,100 km (680 miles) west of Buenos Aires, will be hooked up to a central computer to measure the intensity of the cosmic rays. "It's best to think of this as a new astronomy where there are sources in the Universe which give not light, but very high energy particles," Dr Cronin said. Most cosmic rays are believed to originate in supernovae but the source of the most energetic is not known, black holes and gamma ray bursts have both been suggested. Other scientists believe cosmic rays may be decayed leftovers from massive particles created in the very early Universe, shortly after the Big Bang, said Leeds University physics professor Alan Watson, the Auger Project's other co-director. "It may also be that these particles are created by the matter surrounding black holes, or maybe there are particles in nature we have not yet observed with accelerators," said Professor Watson.
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