Total Dissolved Solids
Sodium (Na) is a major component in drinking water. All water supplies contain some sodium. The amount is dependent on local soil conditions. The higher the sodium content of water, the more corrosive the water becomes. A major source of sodium in natural waters is from the weathering of feldspars, evaporates and clay. The American Heart Association has recommended a maximum sodium level of 20 mg/i in drinking water for patients with hypertension or cardiovascular disease. Intake from food is generally the major source of sodium, ranging from 1100 to 3300 mg/day. Persons requiring restrictions on salt intake, usually have a sodium limitation down to 500 mg/day. The amount of sodium obtained from drinking softened water is insignificant compared to the sodium ingested in the normal human diet. The amount of sodium contained in a quart of softened, 18 grain per gallon water is equivalent to a normal slice of white bread. Sodium in the body regulates the osmotic pressure of the blood plasma to assure the proper blood volume. Sodium chloride is essential in the formation of the stomach acids necessary for the digestive processes. The US EPA sponsored a symposium which concluded that there is no relationship between soft water and cardiovascular disease. There is also no MCL published for sodium, however the US EPA suggests a level of 20 mg/l in drinking water for that portion of the population on severe sodium restricted diets of 500 mg/day or less.
Sodium can be removed with the hydrogen form cation exchanger portion of a deionizer. Reverse osmosis will reduce sodium by 94 - 98%. Distillation will also remove sodium.
AP-RO5500 - For: Drinking Water Systems, under sink.