What Are Nitrates?
Nitrate is a naturally occurring compound that is formed in the soil when nitrogen and oxygen combine. Small amounts of nitrate are normal, but excess amounts can pollute supplies of groundwater.
Where Does Nitrate Come From?
Common sources of nitrogen in the soil are fertilizers, livestock waste, and septic systems. Excess nitrate in the soil ismost often found in rural and agricultural areas. Some areas of the Llagas groundwater basin in southern Santa Clara County have higher than normal concentrations of nitrate.
How Does Nitrate Get Into My Well Water?
Nitrate travels easily through the soil, carried by rain or irrigation water into groundwater supplies. Wells that tap groundwater may be affected. Shallow wells, wells in sandy soil, or wells that are improperly constructed or maintained are more likely to have nitrate contamination.
What Are The Health Effects of Consuming Nitrate?
For most people, consuming small amounts of nitrate is not harmful. Nitrate can cause health problems for infants, especially those six months of age and younger. Nitrate interferes with their blood's ability to transport oxygen. This causes an oxygen deficiency, which results in a dangerous condition called methemoglobinemia, or "blue baby syndrome." The most common symptom of nitrate poisoning is bluish skin coloring, especially around the eyes and mouth. Infants six months of age and younger and pregnant and nursing women should avoid consumption of water high in nitrate.
The good news is that methemoglobinemia is easy for doctors to treat and babies can make a full recovery. Also, as babies grow, their bodies develop the ability to counteract the effects of excess nitrate. Thus, health risks are reduced for children older than six months of age and adults. For more information on the risks of nitrate consumption, consult your own doctor.
Cattle, horses, sheep, baby pigs, and baby chickens are also susceptible to nitrate poisoning. They too can fully recover if treated by a veterinarian in time.
How Do I Know if My Water is High in Nitrate?
Nitrate is colorless and odorless. The surest way to tell if you have nitrate in your water is to have it tested. If your water comes from a public water supply, such as a city supplier, it is tested regularly to ensure that it meets safe drinking water standards. If your water comes from a private well, you are responsible for testing it and ensuring that it is safe to drink. Your Municipality may be willing to test your water free of charge if you are in a risk area.
Areas Susceptible to Nitrate Contamination:
Llagas Groundwater Basin area of southern Santa Clara County
What Can I Do if My Water is High in Nitrate?
Treatment technologies that remove nitrate include reverse osmosis, anion-exchange, and distillation.
Don't boil the water. Boiling water before drinking it DOES NOT remove nitrate. In fact, it causes some of the water to evaporate, which increases the nitrate concentration.
NOTE: People who have Nitrates in their water and have RO systems, must change their Membranes more frequently.
How much is too much?
Nitrate can be measured as NO3 or as NO3-N, and the results mean very different things. Measured as Level (mg/L)
0 - 44 Below the drinking water standard. The nitrate level is safe for humans and livestock.
45-176 Higher than the drinking water standard. The water should not be consumed by infants six months of age or younger, or by pregnant or nursing women. It may be acceptable for adults and livestock though it is not recommended.
176+ Significantly higher than the drinking water standard. The water should not be consumed. Install a water treatment system or use bottled water for drinking and cooking
0-9 Below the drinking water standard. The nitrate level is safe for humans and livestock.
10-39 Higher than the drinking water standard. The water should not be consumed by infants six months of age or younger, or by pregnant or nursing women. It may be acceptable for adults and livestock though it is not recommended.
40+ Significantly higher than the drinking water standard. The water should not be consumed. Install a water treatment system or use bottled water for drinking and cooking.