| What is nitrate? How does nitrate get into water supplies? What effect does nitrate have on family and animals? How can nitrate be detected? How can nitrate levels be reduced? |
| What is Nitrate? |
| Nitrate (NO3) is the primary source of the essential nutrient, nitrogen (N), for plants. Nitrogen is often added to fertilizers, because without it plants could not live. |
| How does Nitrate Get Into Water Supplies? |
| Contamination occurs when there is more nitrate in the soil than plants can absorb.
The excess is carried through the soil into groundwater supplies by rainwater and
irrigation. Naturally, agricultural areas, where heavy farming is performed, tend to have more nitrate-contaminated water supplies than other areas. However, contamination can also occur from surface water runoff and from septic tanks leaching into wells. |
| What Effect Can Nitrate Have On Family And Animals? |
| Human babies, ruminant animals (such as cows and sheep) and infant monogastrics (such as baby pigs and chickens) are extremely susceptible to nitrate poisoning because of certain nitrate converting bacteria present in their digestive systems. These bacteria can change nitrate into toxic nitrite (NO2), which then reacts with hemoglobin. Hemoglobin performs the vital function of carrying oxygen to all parts of the body. When nitrite combines with hemoglobin, methemoglobin is formed, which does not carry oxygen. As the level of hemoglobin is reduced and the level of methemoglobin increases, babies and infant animals can suffocate. |
| How Can Nitrate Be Detected? |
| Use a Nitrate test trip to test for approximate nitrate level. |
| Have a Water Analysis Lab to measure the exact nitrate level. |
| The maximum contaminant level for nitrogen-nitrate, as established by the Safe Drinking Water Act, is 10 milligrams per liter (mg/l as N). |
| How Can Nitrate Be Reduced? |
| Since nitrate is a very soluble substance, it is easily dissolved in water and difficult to get out. The four methods of reducing nitrate are: |
| Anion Exchange |
| The nitrate trades places with another substance, commonly chloride, during this process. As water flows through an exchange tank, resin takes up nitrate in exchange for chloride. A drawback to this system is that sulfates are also exchanged along with the nitrate, diminishing the capacity of the resin to take out nitrate. Regeneration effluents must also be disposed of so ground water supply is not recontaminated with nitrate. |
| Blending |
| Nitrate-polluted water is diluted with water from another source which is not high in nitrate concentrations. Although frequently used for livestock, blended water is not considered safe for infants. |
| Distillation |
| Through distillation, nitrate and other minerals remain in a boiling tank
as the steam from boiling water in it rises and is caught. The steam is condensed on a
cold surface, turning back into water. Although effective for nitrate reduction,
distillation produces flat, tasteless water. |
| Reverse Osmosis |
| During reverse osmosis, water is slowly forced under high pressure through a membrane that filters out many contaminants, including nitrate. |