Chloramines in Drinking Water

Many municipal water supplies have switched from chlorine to an alternative method of disinfection to reduce the formation of trihalomethanes (THMs). Chloramine, or chloramination, is a treatment method employed by public water systems, more than one in five Americans uses drinking water treated with chloramines. Chloramines do pose a risk for hemodialysis patients and fish. Nitrosamines can be generated as byproducts from use of chloramines. They are strongly suspected of being human carcinogens.
Contaminant  In Water As Maximum Residual Disinfectant Level



Nitrogen Trichloride





MRDL* = 4.0 mg/L or ppm (measured as Cl2)

MRDLG** = 4.0 mg/L or ppm (measured as Cl2)

Sources of Contaminant

Municipal Treatment

Potential Health Effects

Can cause hemolytic anemia when present in dialysis process water

Treatment Methods

Point-of-Entry (POE)

Point-of-Use (POU)


Activated Carbon

Catalytic Activated Carbon

*Maximum Residual Disinfectant Level (MRDL) - The highest level of a disinfectant allowed in drinking water. There is convincing evidence that addition of a disinfectant is necessary for control of microbial contaminants.

**Maximum Residual Disinfectant Level Goal (MRDLG) - The level of a drinking water disinfectant below which there is no known or expected risk to health. MRDLGs do not reflect the benefits of the use of disinfectants to control microbial contaminants.)

Click here to open WQA's Technical Fact Sheet on Chloramine.

Click here to access all of WQA's Technical Fact Sheets.