Filtered deionized water is a form of "Purified water" that comes from a municipal water source and is processed to remove dissolved impurities such as sodium, calcium, iron, copper, chloride and bromide. Deionization is a physical process which removes ions from water via ion exchange resins. Because the majority of water impurities are dissolved salts, deionization produces a high purity water that is generally similar to distilled water. However, deionization does not significantly remove uncharged organic molecules, viruses or bacteria, except through "accidental" trapping by the resin.