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 odor.

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 carbon.