FUKUSHIMA Lives on the Line

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193chap.IVPatient Relief Activity Records [Essays and Research Publications]FUKUSHIMA: Lives on the Linewas to prevent American citizens from burdening Japan, and cordial Japanese hosts, where infrastructure was damaged and resources were limited. Americans with emergency response, medical, and/or nuclear safety expertise have, along with other nationals, freely traveled and worked in Japan's disaster-affected areas.2. American HibakushaIn the early 1970s, a guest speaker visited Hibbing High School in the City of Hibbing, capital of St. Louis County in the State of Minnesota. Students assembled in the Hibbing High School Auditorium to learn about nuclear power and radiation. The guest speaker sought a volunteer. From those in the audience who raised their hands, he invited a high school girl onto the stage and asked her to assist with some task. After the task, the speaker offered her a drink of cola as a small reward. The student politely accepted. A conversation along the following lines ensued :Speaker : “Refreshing?"Student : “Yes."Speaker : “Suppose I said your cola was radioactive?"Student : [Surprised silence.]Speaker : “Watch."The speaker turned on a Geiger counter and started to wand our volunteer. As the detector approached her throat, the occasional clicks became much more frequent. This got everyone's attention.Speaker : “No, I did not give you radio­active cola. Radioactive substances are tightly regulated, and I am not a medical doctor. Your thyroid gland, at the front of your throat, naturally attracts iodine, some of which is radioactive."To the best of my recollection, the speaker gave no particular details about the extent to which radioactive iodine might be found in nature. However, St. Louis County was downwind of an unnatural source of radioactive iodine: the Nevada Test Site, where 100 of America's 210 atmospheric tests of nuclear 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)DISCUSSIONThis 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 K. E. Nollet

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