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506AMERICAN HIBAKUSHA2. Fukushima Fukushima, too, has entered the general English lexicon as a name associated with detrimental effects of ionizing radiation. In a specialized English lexicon, Fukushima had previously been associated with a beneficial effect. In 1988, Fukushima Medical University was the first institution worldwide to treat all allogeneic donor blood cell products with ionizing radiation to prevent transfusion-associated graft-versus-host disease4). Modern authors continue to cite pioneering articles on graft-versus-host disease from Fukushima Medical University5,6). General public knowledge about Fukushima is another matter. The prefecture was renowned as a tourist destination and agricultural center, but most people did not know that two nuclear plants on Fukushima's Pacific coast were dedicated exclusively to Tokyo's massive demand for electricity. These are the Fukushima 1 and 2 Nuclear Power Plants, now known around the world by their Japanese designations, Fukushima Daiichi and Fukushima Daini.THE PRICE OF POWER Per kilowatt-hour, nuclear plants have been promoted as being less expensive than other sources of electricity, but indirect, human costs are once again earning some attention. Recent investigations have suggested that from 2003 through 2008, on the basis of workplace radiation exposure, Fukushima Daiichi was among the world's five highest-risk nuclear plants, the other four being in the United States, Spain, lndia, and Mexico7). Through various safety initiatives by TEPCO, the Tokyo Electric Power Company, working conditions seemed to be improving at Fukushima Daiichi in the years just prior to March 11, 20117). On March 11, 2011, a magnitude 9.0 earthquake originated off the Pacific coast of Japan's Tohoku district. Nuclear power stations Onagawa (Miyagi Prefecture, est. 1984), Fukushima Daiichi and Daini (Fukushima Prefecture, est. 1971 and 1982), and Tokai Daini (Ibaraki Prefecture, est. 1978) went into automatic shutdown8). The earthquake and related tsunami have been implicated in subsequent failures, radiation release, and core meltdowns at the oldest of these power stations, Fukushima Daiichi. Remote video images of gas-releasing explosions at Fukushima Daiichi were promptly and repeatedly aired on commercial and public television. At Fukushima Medical University, 57 kilometers from Fukushima Daiichi, the leading edge of a spike in background radiation was observed on the evening of March 15. In a physics professor's office, a peak value of 9.3 times average was recorded in the early hours of March 16. As of October 11, 2011, the decay curve of this increased background radiation could be resolved into a short harf-life of 3.74 days and a long half-life of 242 days. These half-lives do not refer to specific radioactive isotopes, but are calculated by non-linear regression analysis from actual data to forecast further decreases in radioactivity. As of October 11, background radiation at the office where the March 15-16 spike was detected was down to 1.50 times the average background observed prior to the spike. Although radioactive isotopes of cesium and strontium have half-lives around 30 years, background radiation decreases faster as isotopes are progressively dispersed into the environment. For example, the aforementioned decay curve includes a noticeable dip in background radiation on July 28, corresponding to a day of heavy rain.AMERICAN PERSPECTIVES1. Americans in Japan On March 17, the US Department of State announced online and by email that US citizens within 50 miles (80 km) of Fukushima Daiichi should evacuate the area or take shelter THE GREAT EAST JAPAN EARTHQUAKE "3.11"

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