May be associated with the presence of sodium in drinking water when present in high concentrations. Often from saltwater intrusion, mineral dissolution, industrial and domestic waste. Deteriorates plumbing, water heaters, and municipal water-works equipment at high levels.
Cost basis is the original price paid for shares of a security plus or minus certain adjustments required by applicable tax rules such as adjustments with respect to reinvested distributions and sales charges.
Cost basis is most often used for tax purposes. When an asset is sold, it is used to determine the capital gain or loss, which is the difference between the asset's cost basis and its current market value.