Nitrates in a water supply can occur naturally or can be caused by fertilizer, manure or sewage contamination.
The U.S. Center for Disease Control says nitrate is a compound that forms naturally when nitrogen combines with oxygen or ozone. Nitrogen is essential for all living things, but high levels of nitrate-nitrogen in drinking water can be dangerous, especially for infants and pregnant women.
Nitrates naturally occur when there are more nitrates in the soil than plants can use. The excess nitrate is carried through the soil into ground water.
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The CDC says that high levels of nitrate in well water often result from improper well construction and location, overuse of chemical fertilizers or improper disposal of human and animal waste.
Under Canadian guidelines, the maximum level of nitrate is 45 milligrams per litre of drinking water. Infants younger than six months are particularly at risk from drinking well water that has excessive nitrates.
Levels this high react with the hemoglobin that carries oxygen throughout the body, especially the brain. Infants drinking water with levels of nitrate exceeding this level could develop blue baby syndrome.
I have a problem with any department or organization placing guidelines on certain substances in water, especially nitrates. They tell us that water with 45 mg per L is unsafe for infant consumption. What if we have 44 mg per L of nitrates. Is it safe then?
I believe water should be free of all contaminants and there should be no guideline for nitrates in a water supply.
To prevent nitrate contamination, control runoff and water erosion and prevent sources of nitrogen such as fertilizers, manure and sewage from getting into the water source.
If you have a nitrate problem, the two most common water purification devices are distillation or reverse osmosis systems.
Remember, however, that these systems usually are used to purify only drinking water. When you bathe, your skin can absorb as much as 60 percent water, which should be of concern especially when bathing infants.
If you have a specific water problem and would like advice, write to the Water Clinic, attention Philip Stadnyk, 850-47th St. E. Saskatoon, Sask., S7K 0X4, e-mail philip@thewaterclinic.com or phone 800-664-2561. Stadnyk is president of the Water Clinic and a member of the Canadian Water Quality Association. His views do not necessarily reflect those of The Western Producer.