Four of the five counties in the nation hit hardest with I-131 are in Idaho (the top county is in Montana).

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The government knew at least as early as the mid-1940s that potassium iodide was protective against I-131 absorption by the thyroid.

FORBES: 1st Person | Facing an Unsettled Future After Radiation Exposure

But in fact the most likely source of that I-131 lay to the southwest: the Nevada Test Site near Las Vegas.

FORBES: 1st Person | Facing an Unsettled Future After Radiation Exposure

Their I-131 concentrations appear at the very low end of the range, but are estimated to be drifting both south and east.

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The National Cancer Institute exposure calculator says I probably received a total of 10 rads of I-131 from 47 separate tests between 1951 and 1966.

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The Massachusetts Department of Health said Sunday that a monitoring station in Boston detected I-131 in rainwater on March 22, but had not detected any in air.

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Regarding the nuclear plants, Spiegel Online is showing a simulation of radioactive drift of I-131 (radioiodine) from the Viennese Central Institute for Meteorology and Geodynamics (ZAMG).

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What does Class of Admission mean on I-131?

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State and County Exposure Levels to I-131.

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That the region was rapidly evacuated and everyone told not to eat anything from that area (for two months as I-131 decayed away), was all that was needed to reduce any threat of thyroid effects and all other cancers from most of the affected areas.

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