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          Naturally occurring sources

          Radiation is common in nature. It is part of the foods we eat, like bananas, carrots, white potatoes, and Brazil nuts. It is also part of solar radiation, in cosmic rays, and in minerals and materials found in the earth’s crust, such as potassium-40, uranium-238, radium-226, radon-222. The oil and natural gas mining industry dredges up radon and radium elements referred to as Natural Occurring Radioactive Material (NORM).

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