FUKUSHIMA Lives on the Line

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192General 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 power 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 POWERPer kilowatt-hour, nuclear power 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 power 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).THE GREAT EAST JAPAN EARTHQUAKE "3.11"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 JapanOn 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 indoors if safe evacuation is not possible. This recommendation was attributed to the US Nuclear Regulatory Commission, and said to be in accord with directives that would be issued for a comparable event in the United States. Other governments issued similar advice.This author, an American citizen employed by Fukushima Medical University since January 2008, subscribes to an advisory service of the United States Embassy in Tokyo. The embassy made a health and welfare inquiry by telephone on March 16, and sent an email with evacuation advice on March 17. Subsequent emails in March included information about travel assistance available to US citizens and their dependents. Through September 18, 2011, the United States Embassy in Tokyo continued to advise, “out of an abundance of caution," that citizens living within 80 km of Fukushima Daiichi “evacuate or shelter in place." The March 17 recommendation was modified on May 16 to say that the risk of travel through the area by bullet train or expressway was low. A July 19 travel alert added that it was deemed a low risk to travel to, from, and through Sendai Airport.Fully aware of official US recommenda­tions, this author continued working at Fukushima Medical University and living about 2 km away. No coercion was involved; in fact, neighbors and colleagues were rather surprised by what seemed to be an act of defiance against the US government by one of its citizens. However, my advice to others, including an American journalist and a Congolese graduate student, was for them to heed the advice of their respective governments, both of which recommended being outside of Japan's post-3.11 risk areas.It is the opinion of this author that one motivation for the US Embassy's evacuation advice and assistance American Hibakusha

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