In reverse osmosis, water is put under pressure and forced through a membrane to filter out minerals and nitrate. Ion exchange may also be used, and is similar to the way water is softened. Most often, chloride is exchanged for nitrate in tanks filled with resin beads charged with chloride. A blending process may also be used by diluting nitrate-polluted water with water from another source low in nitrate concentration. It is not considered safe enough for infants, environment officials note.
Boiling water is the worst thing to do, experts say, because it actually concentrates the nitrate.
Softening and filtration alone do nothing to remove nitrate. References National Agriculture Safety Database. Service in Action, 0.517. Read our Privacy Policy .