Chloramination
Encyclopedia
Chloramination is the treatment of drinking water
with a chloramine
http://www.wqa.org/pdf/TechBulletins/TB-Chloramine.pdf disinfectant. Both chlorine
and small amounts of ammonia
are added to the water one at a time which react together to form chloramine (also called combined chlorine), a long lasting disinfectant. Chloramine disinfection is sometimes used in large distribution systems.
(EPA).
The EPA regulations give two choices for disinfectant residual — chlorine or chloramine. Many major water agencies are changing to chloramine to better meet current and anticipated federal drinking water regulations and to protect the public health
.
and reptiles. Both chlorine and chloramine react with other compounds in the water to form what are called “disinfection byproducts”.
The difference is that chlorine forms many byproducts, including trihalomethanes (THM) and haloacetic acids
(HAA), whereas chloramine forms a significantly lower amount of THMs and HAAs but also forms N-nitrosodimethylamine
(NDMA). One of the principal benefits of chloramine is that its use reduces the overall levels of these regulated contaminants compared to chlorine.
machines, since water comes into direct contact with the bloodstream during treatment. When drinking water, people have no trouble digesting chlorine or chloramine at the levels found in our drinking water; this water is not introduced directly into the bloodstream.
Much of the discussion about chloramine has focused on NDMA, and it is critical to distinguish between chloramine and NDMA. NDMA can be a byproduct of chloramination or chlorination, but drinking water is not a major source of exposure to NDMA. The biggest sources of human exposure to NDMA are tobacco
smoke, chewing tobacco, bacon
and other cured meats, beer
, fish, cheese
, toiletries, shampoo
s, cleansers, interior air of cars, and household pesticides. In addition, NDMA can form in the stomach during digestion of foods or drugs that contain alkylamines, which are naturally occurring compounds.
At very high levels--100,000 times greater than even the highest levels seen in a recent survey of chlorinated and chloraminated drinking waters--NDMA may cause serious human health problems, such as liver disease. Such effects are seen at concentrations ranging from 5 to 50 parts per million in water; for comparison a study conducted by the California Department of Health Services in 1999 and 2000 found the highest level of NDMA in drinking water that had been treated with chloramine was 0.00006 parts per million. In that study, most of the concentrations of NDMA were far lower than that, and many water samples in the California Department of Health Services study, including those from the San Francisco Public Utilities Commission water system taken in 2000, did not have any detectable concentrations of NDMA.
Drinking water
Drinking water or potable water is water pure enough to be consumed or used with low risk of immediate or long term harm. In most developed countries, the water supplied to households, commerce and industry is all of drinking water standard, even though only a very small proportion is actually...
with a chloramine
Chloramine
Chloramines are derivatives of ammonia by substitution of one, two or three hydrogen atoms with chlorine atoms. Monochloramine is an inorganic compound with the formula NH2Cl. It is an unstable colourless liquid at its melting point of -66° temperature, but it is usually handled as a dilute...
http://www.wqa.org/pdf/TechBulletins/TB-Chloramine.pdf disinfectant. Both chlorine
Chlorine
Chlorine is the chemical element with atomic number 17 and symbol Cl. It is the second lightest halogen, found in the periodic table in group 17. The element forms diatomic molecules under standard conditions, called dichlorine...
and small amounts of ammonia
Ammonia
Ammonia is a compound of nitrogen and hydrogen with the formula . It is a colourless gas with a characteristic pungent odour. Ammonia contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to food and fertilizers. Ammonia, either directly or...
are added to the water one at a time which react together to form chloramine (also called combined chlorine), a long lasting disinfectant. Chloramine disinfection is sometimes used in large distribution systems.
Use
The maintenance of what is called a “residual” of disinfectant that stays in the water distribution system while it is delivered to people's homes is required by the Environmental Protection AgencyUnited States Environmental Protection Agency
The U.S. Environmental Protection Agency is an agency of the federal government of the United States charged with protecting human health and the environment, by writing and enforcing regulations based on laws passed by Congress...
(EPA).
The EPA regulations give two choices for disinfectant residual — chlorine or chloramine. Many major water agencies are changing to chloramine to better meet current and anticipated federal drinking water regulations and to protect the public health
Public health
Public health is "the science and art of preventing disease, prolonging life and promoting health through the organized efforts and informed choices of society, organizations, public and private, communities and individuals" . It is concerned with threats to health based on population health...
.
Chlorine v. Chloramine
There are many similarities between chlorine and chloramine. Both provide effective residual disinfection with minimal risk to public health. Both are toxic to fishFish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...
and reptiles. Both chlorine and chloramine react with other compounds in the water to form what are called “disinfection byproducts”.
The difference is that chlorine forms many byproducts, including trihalomethanes (THM) and haloacetic acids
Haloacetic acids
Haloacetic acids are carboxylic acids in which a halogen atom takes the place of a hydrogen atom in acetic acid. Thus, in a monohaloacetic acid, a single halogen would replace a hydrogen atom. For example, chloroacetic acid would have the structural formula CH2ClCO2H. In the same manner, in...
(HAA), whereas chloramine forms a significantly lower amount of THMs and HAAs but also forms N-nitrosodimethylamine
N-Nitrosodimethylamine
N-Nitrosodimethylamine , also known as dimethylnitrosamine , is a semi-volatile organic chemical that is highly toxic and is a suspected human carcinogen. The US Environmental Protection Agency has determined that the maximum admissible concentration of NDMA in drinking water is 7 ng L−1...
(NDMA). One of the principal benefits of chloramine is that its use reduces the overall levels of these regulated contaminants compared to chlorine.
Adverse Effects
Chloramine is toxic to fish and reptiles (chloramine, like chlorine, comes in direct contact with their bloodstream through their gills) and must be removed from water added to aquariums and fish ponds. It must also be removed from water prior to use in dialysisDialysis
In medicine, dialysis is a process for removing waste and excess water from the blood, and is primarily used to provide an artificial replacement for lost kidney function in people with renal failure...
machines, since water comes into direct contact with the bloodstream during treatment. When drinking water, people have no trouble digesting chlorine or chloramine at the levels found in our drinking water; this water is not introduced directly into the bloodstream.
Much of the discussion about chloramine has focused on NDMA, and it is critical to distinguish between chloramine and NDMA. NDMA can be a byproduct of chloramination or chlorination, but drinking water is not a major source of exposure to NDMA. The biggest sources of human exposure to NDMA are tobacco
Tobacco
Tobacco is an agricultural product processed from the leaves of plants in the genus Nicotiana. It can be consumed, used as a pesticide and, in the form of nicotine tartrate, used in some medicines...
smoke, chewing tobacco, bacon
Bacon
Bacon is a cured meat prepared from a pig. It is first cured using large quantities of salt, either in a brine or in a dry packing; the result is fresh bacon . Fresh bacon may then be further dried for weeks or months in cold air, boiled, or smoked. Fresh and dried bacon must be cooked before eating...
and other cured meats, beer
Beer
Beer is the world's most widely consumed andprobably oldest alcoholic beverage; it is the third most popular drink overall, after water and tea. It is produced by the brewing and fermentation of sugars, mainly derived from malted cereal grains, most commonly malted barley and malted wheat...
, fish, cheese
Cheese
Cheese is a generic term for a diverse group of milk-based food products. Cheese is produced throughout the world in wide-ranging flavors, textures, and forms....
, toiletries, shampoo
Shampoo
Shampoo is a hair care product used for the removal of oils, dirt, skin particles, dandruff, environmental pollutants and other contaminant particles that gradually build up in hair...
s, cleansers, interior air of cars, and household pesticides. In addition, NDMA can form in the stomach during digestion of foods or drugs that contain alkylamines, which are naturally occurring compounds.
At very high levels--100,000 times greater than even the highest levels seen in a recent survey of chlorinated and chloraminated drinking waters--NDMA may cause serious human health problems, such as liver disease. Such effects are seen at concentrations ranging from 5 to 50 parts per million in water; for comparison a study conducted by the California Department of Health Services in 1999 and 2000 found the highest level of NDMA in drinking water that had been treated with chloramine was 0.00006 parts per million. In that study, most of the concentrations of NDMA were far lower than that, and many water samples in the California Department of Health Services study, including those from the San Francisco Public Utilities Commission water system taken in 2000, did not have any detectable concentrations of NDMA.