Reverse osmosis fresh drinking water

The term water is used to describe potable water that is freshly drawn direct from the public supply and is suitable for drinking. The chemical composition of potable water is variable and the nature and concentrations of the impurities in it depend upon the source from which it is drawn. Although potable water must be both palatable and safe to drink, for most pharmaceutical applications potable water is purified by distillation, ion exchange treatment, reverse osmosis, or some other suitable process to produce purified water . For certain applications, water with pharmacopeial specifications differing from those of purified water should be used, e.g. water for injection see Sections 9 and 18. 

Reverse osmosis is very important in environmental preservation and sustainability. One of its applications is to the acquisition of fresh water from seawater, and several arid countries now obtain significant water supplies by reverse osmosis. Irrigation water picks up dissolved salts from fertilizer and other sources, so that runoff from irrigation water may be too saline. Reverse osmosis has been used to desalinate such water. Wastewater that has been through municipal water systems picks up significant amounts of sodium chloride (table salt) and other dissolved salts. Therefore, reverse osmosis is an important step in the renovation of such water to drinking water standards. 

Gerald Parkinson, Charlene Crabb, and Takeshi Kamiya, "Seawater Gets Fresh," Chem. Eng., Vol. 106(3), 1999, 32-35. An article that looks at the role of desalination and reverse osmosis in providing drinking water. 

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