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Pb = Lead banana? Mung

Pb-208 most likely Robert Sheldon

Bananas are rich in potassium, designated by the symbol K, for "kalium" as they say in europe. One of the isotopes of potassium, 40K, is radioactive. This makes bananas the most radioactive food you can eat, that is, excluding a meal of lemon slices served on Fiestaware. In fact, in an effort to rehumanize radioactivity, several people have proposed to measure it not in "curies" named for Marie, but in "bananas", just so you understand how little danger is being discussed. After all, wouldn't it be a lot less frightening if you heard that food grown in Fukushima province was deemed "safe" if it had less than 0.5 bananas of radiation? But when K40 decays, it does so three different ways (a bit unusual) but the most common is to give off an electron and an anti-neutrino. Now it has a much less likely decay into an anti-electron and a neutrino. The "anti-" prefix means that if it collides with a normal version, they both vanish in a puff of gamma rays. However, and this is a big however, neutrinos don't interact with anybody, much less with another neutrino, so that "anti-" on the neutrino is just for looks, it might as well have been a normal neutrino. All that to say that K40 decay contributes to normal matter, and only very rarely subtracts from normal matter (by emitting that suicidal anti-electron). If the Big Bang likewise had a bias for normal matter, then we don't expect to see a galaxy of anti-matter for every galaxy of normal matter. Which just goes to show that some biasses are vitally good. And no, the anti-electron will not make the banana explode. That was done with a few quadrillion Pb-103 atoms travelling 2500 feet/sec. Robert Sheldon