Just before dawn on April 26th, 1986, the Number Four nuclear reactor at Chernobyl exploded. The fallout was 400 times more radioactive than what was released over Hiroshima during World War II, and it covered an area the size of New Jersey. Numerous radioactive elements were released into the air - including radioactive iodine, an element that is preferentially taken-up by the thyroid gland. As a result, there was a rise in cancer - and, in particular, in thyroid cancer in children. (Since the thyroids of children are much smaller than adults, it is assumed that the relative dose of radioactive iodine these thyroids received was much larger than the adult thyroids.)
Following the accident, an international panel of experts was formed to study the after-effects of the accident. One group of specialists - including pathologists who, like Dr. LiVolsi, have expertise in thyroid pathology - was charged with studying the thyroid tumors that had occurred to reach a consensus diagnosis. These analyses, including samples of the tumors, have been made available to the international research community to further our understanding of thyroid-cancer development and radiation-induced tumors.
The isotopes of radioactive iodine that are suspected of causing the outbreak of thyroid cancer have a relatively short half-life of eight days, but other isotopes that were released in the explosion -- like cesium 137 and strontium 90, will last for decades. One of the interesting aspects of this research is that we are still seeing new thyroid-cancer tumors in the exposed population - even though, after 20 years, there is no radioactive-iodine fallout left from the accident," LiVolsi said. "In the future, it will be informative to compare tumors that appeared initially to those that are occurring now."
Chernobyl is still a threat to this day. The lead and steel sarcophagus initially built around the Number Four Reactor has decayed. A replacement structure is in the planning stages. This replacement will take four-five years to assemble, cost over $800 million and be the largest movable structure ever built.
However, information learned from the Chernobyl accident could prove valuable insofar as aiding and treating future victims of a "dirty bomb" - a conventional explosion that scatters radioactive materials, including the longer-lasting strontium 90 and cesium 137. According to the Department of Homeland Security's National Terror Alert Resource and Information Center website, the Washington Post reported in March of 2002 that the Bush administration's consensus view is that the al-Qaeda terrorist network probably had such acquired often-stolen radioactive contaminants as strontium 90 and cesium 137, which could be used in a "dirty bomb."
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