FACT - All natural products, especially stone, minerals, and sand, contain trace amounts of some radioactive elements called NORMs (Naturally Occurring Radioactive Mineral) that can produce measurable amounts of radiation and sometimes radon gas.
This includes all concrete products, clay bricks, most non-plastic plates and dishes, coal and the flyash produced in coal-fired power plants, natural gas (contains radon), phosphate fertilizers used in your garden (ALL contain potassium and small amounts of uranium and thorium), and the vegetables grown using those fertilizers. The Border Patrol often catches truck loads of marijuana because it is loaded with radiation producing potassium), all glass made using silica (even eye glasses, wine glasses, mirrors, windows, etc.), and granite too.
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