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508AMERICAN HIBAKUSHAnuclear weapons were conducted between January 1951 and July 19629). The exposure of Americans to radioactive iodine from the Nevada Test Site was not comprehensively investigated until Public Law 97-414 was enacted in 1993, although smaller investigations had been previously reported10). As directed by Public Law 97-414, the US National Cancer Institute published results in 199711). In the 1950s, about 150 million curies ─ in modern terms 5.6×1018 becquerels ─ of I-131 entered the atmosphere from atomic bombs detonated at the Nevada Test Site. The average thyroid dose to 160 million Americans during the 1950s was 20 millisieverts. St. Louis County residents, 2,200 km from the Nevada Test Site, received an average thyroid dose of 60-90 millisieverts. Not only location, but also milk consumption and thyroid size were significant factors in an individual's exposure. Children 3 months to 5 years old exceeded the average thyroid dose by 3-7 times11). What were citizens told about radiation in the era of atmospheric testing of nuclear weapons? A woman who grew up in southern Utah, just east of Nevada, recalled that when visitors with Geiger counters came to her primary school, she was told that dental X-rays were the cause of elevated readings when a Geiger counter was aimed at her face12). A transfusion medicine colleague who grew up in North Dakota, just west of northern Minnesota, said that as a child she was told not to chew on grass outdoors, because it was tainted with strontium (Anne Kaldun, personal communication). Cows are more frequent consumers of grass than well-fed children, but American literature (e.g., The Adventures of Huckleberry Finn by Mark Twain) and art (e.g., illustrations by Norman Rockwell) conjure up images of rural children chewing on straws of hay as they work or play outdoors. In the same decade that Anne Kaldun was admonished not to chew on strontium-tainted grass in North Dakota, Japanese investigators were systematically measuring and reporting strontium-90, cesium-137, and plutonium-239 fallout in the atmosphere, rainwater, soil, and food supply in Japan.13)DISCUSSION This author, born in 1958, and Americans of similar age were hibakusha as a result of growing up in the era of atmospheric nuclear weapons testing. What we were told about this was limited, perhaps misleading, or at least inconsistent with what is now in the public domain. Retrospectively, the spread of radioactive iodine across the continental United States was the main health consequence of atom bomb detonations at the Nevada Test Site, although other isotopes, such as radioactive cesium, were released as well. Hydrogen bomb detonations around the world fueled a global spread of radioactive strontium10), so people of every nationality can be counted as hibakusha9,10). Saying so should never diminish the significance of this word as it applies to people of Hiroshima and Nagasaki. Rather, this statement of fact should be a touchstone, through which citizens of the world might empathize with the unique history of Japan: a World War II target of two atomic bombs, a Cold War recipient of radioactive fallout that contaminated the food supply, and the most recent nation to deal with a nuclear power plant meltdown.ACKNOWLEDGMENTS Background radiation data at Fukushima Medical University came from Professor Tsuneo Kobayashi, Chair of the Department of Natural Sciences (Physics) at Fukushima Medical University. Professor Kobayashi is one among many in Fukushima who make factual data about our current nuclear crisis freely available to scholars and to the general public. Various members of FMU's academic community, and residents of the Hourai neighborhood of Fukushima City, continue to inconvenience themselves for the American among them (just as the US Embassy predicted). Personal narratives and photographs related to life and work in post-

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