Water
Filtration - Contaminants in Water
 Nitrates
and Nitrites
Nitrates
and nitrites are a major constituent of fertilizers and
have been used for many years in lawn treatments. Without
the addition of these, crops would deplete nitrogen from
soil. Unfortunately, when nitrogen fertilizers are used,
they can get into wells and contaminate them. Nitrates
and nitrites from these fertilizers also seep into groundwater,
especially shallow wells . The Environmental Protection
Agency has set a maximum contaminant level (MCL) of 10
mg/L for nitrate and nitrite in public water supplies.
Users of private water supplies should have their water
tested annually, especially in areas where fertilizers
are commonly used. It is estimated that 1.5 million people
are potentially exposed to nitrates from rural domestic
wells. Nitrites
are cause for concern in infants under 6 months of age and farm animals. They affect the blood's ability to carry oxygen. Nitrites get
into the body when nitrates are ingested, both from food
and water, and nitrate reducing bacteria in an infant's digestive tract
converts
the nitrate to nitrite. Once the nitrite enters the blood
stream and binds to the hemoglobin, oxygen cannot be carried, and "blue-baby" syndrome (bluish tint to skin due to lack of oxygen) occurs, as well as shortness
of breath, increased sensitivity to illness, heart attacks,
and possibly death by asphyxiation. However, as the infant ages, stomach
acid becomes
stronger, and bacteria that cause the conversion of nitrate
to nitrite are reduced. Older children and adults generally do not have
a problem
with nitrates. By the age of six months, the digestive
system is fully developed, and the risk of nitrate-induced methemoglobinemia
is greatly
reduced.
If
nitrates are a concern in your area, it is best to use bottled water
for the infant's formula. Boiling the water will not make the nitrates
go away, it will instead cause an increase in the amount of nitrates
present (2).
The best way to tell if your water has nitrates is to have it tested by a reputable
lab. If your water is found to be contaminated, it can be treated in a variety
of ways, including filtration, distillation, or a system similar to a water
softener.
Treatment
Options
Because
nitrate is tasteless and odorless, water must be chemically
tested to determine contamination.
If your water contains greater than 10 mg/L NO3-N, your options for reducing
health risks are substitution, in-home treatment, and source elimination. Nitrate
is easily dissolved in water, which means that it is difficult to remove. Three
water treatment systems that remove nitrate are distillation,
reverse osmosis, and ion exchange.
- Distillation
boils water, then catches and condenses the steam while
nitrate and other minerals remain in the boiling tank.
- Reverse
osmosis forces water under pressure through a membrane
to filter out contaminants.
- Ion
exchange introduces another substance, normally chloride,
to "trade places" with nitrate in water.
New Filter
Introduced
Treatment
of drinking water to remove nitrate has been expensive.... until now!
Simple household treatment procedures such as boiling, filtration, disinfection,
and water softening do not remove nitrate from water. Boiling actually
increases the nitrate concentration of the remaining water. We now have
a Prefilter which will remove the Nitrate from your water. Please check
our Filter section for details.
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