In mid-ocean ridge areas, ocean water is cycled through the crust because of the high heat flow in the area. Water in the rock is heated over the magmas, rising up and drawing in cold water from the sides. This process is occurring all over the world, and is the primary means for maintaining ocean salinity in a relatively constant range over the long term, as elements in the sea water when it is heated react with the rocks. There is so much water flow, cumulatively over the entire world, that this process basically buffers ocean chemistry.
Obviously large increases or decreases in salinity can and do occur in isolated basins that do not have free exchange with the open oceans.
Decaying uranium atoms in the earth's crust result in Radon gas. Radon gas cannot be synthetically or commercially produced. It is produced as the result of the natural breakdown of uranium i.e. decaying uranium atoms. Radon gas is a naturally occurring radioactive gas. People are exposed to Radon gas via the inhalation and ingestion of the gas. Because it is found in the ground, water or building materials, Radon gas can enter work buildings as well as private dwellings.
Daily exercise and a healthy well-balanced diet.
