Comment: The particles to worry about

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The particles to worry about

are not the subatomic particles that are emitted as radiation so much as the immensely larger particles that consist of clumps of atoms of radionuclide elements. These can be invisible to the naked eye, like a very, very fine dust, but can lodge in the lungs or in the irregular surface of your skin and repeatedly bombard you in the same tiny site as each unstable atom collapses into a more stable element and shoots out subatomic particles.

New Hampshire and Ecuador.