<p>This video shows very low levels of radioactivity from potassium chloride salt substitute being measured with a simple geiger counter with a pancake probe.
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The radioactivity seen here presumably comes from small amounts of naturally-occuring radioactive potassium 40 contained in the salt substitute. The radiation here is very low, and is not considered hazardous. Accordimg to Wikipedia, potassium 40 is found naturally inside the human body causes more than 4000 counts per second of radioactivity (more than 240000 CPM), hundreds of times more than what is measured here.
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<a rel="nofollow" class="external text" href="https://www.youtube.com/watch?v=9ug7LZY_8Ho">Radioactive Salt Substitute - potassium chloride</a>