Posted by Administrator on 12/18/2009
Chloramines are disinfectants used to treat drinking water.
Chloramines are most commonly formed when ammonia is added to chlorine
to treat drinking water. The typical purpose of chloramines is to
provide longer-lasting water treatment as the water moves through pipes
to consumers. This type of disinfection is known as secondary
disinfection. Chloramines have been used by water utilities for almost
90 years, and their use is closely regulated. More than one in five
Americans uses drinking water treated with chloramines. It is added in
very small amounts to treated water to provide continuous disinfection
in the pipes and tanks that distribute drinking water.
Chloramines itself is colorless, tasteless and odorless. In
comparison to chlorinated water. Chloraminated water does not have a
strong chlorine taste. Most consumers should not notice a change in
taste. Many consumers from other utilities report chloramines improve
the taste and odor of drinking water by decreasing chlorine taste and
Chloramines do pose a risk for hem-dialysis patients and fish.
Chloramines easily enter the bloodstream through dialysis membranes and
the gills of fish. Once in the blood stream, chloramines denature
hemoglobin and cause hemolytic anemia. Accidental use of chloramines
treated water for dialysis has been responsible for a number of patients
requiring transfusion to treat resultant hemolytic anemia, and was a
possible factor in an increased mortality (death) rate among the
dialysis center patients during the 5 months after the chloramines
exposure when compared to the 12 months before the chloramines exposure.
While chloramines are not a drinking water health concern to humans
generally, their removal improves the taste and odor of drinking water.
Chloramines are small, stable molecules with no net charge making them
difficult to remove by distillation, reverse osmosis, and ion exchange
resins. Due to the reaction of aqueous chlorine with organic nitrogen,
chloramines also present a concern for municipal water systems utilizing
chlorine as a method of disinfection. Chloramines cannot be removed by
boiling water, adding salt, or letting water stand still. Treatment
devices to remove chloramines are available. These devices should be
specifically certified to remove chloramines. Although home filtration
systems will reduce the level of chloramines from water, it may not
remove it completely.
Carbon filtration or water treatment products that neutralize
chloramines may be used. If you use a carbon filter it must contain high
quality granular activated carbon and you must permit sufficient
contact time. Activated carbon does not adsorb chloramines but rather
removes them through its ability to act as a catalyst for the chemical
breakdown of chloramines to innocuous chlorides in water. The most
effective nonchemical method for removing chloramines is activated