Ureterolysis

Trihalomethanes (THMs) are chemical compounds that are often found in water as a byproduct of chlorination. They are formed when chlorine or other disinfectants used to control microbial contaminants in drinking water react with naturally occurring organic and inorganic matter in water. The four members of the THM family are chloroform, bromodichloromethane, dibromochloromethane, and bromoform.

Health Effects

Exposure to THMs in drinking water can result in a number of health effects. These effects can vary depending on the level and duration of exposure. Some studies have suggested that high levels of THMs in drinking water can increase the risk of certain types of cancer, including bladder and colorectal cancer. Other studies have suggested a possible link between exposure to THMs in drinking water and adverse reproductive outcomes, such as spontaneous abortion, birth defects, and low birth weight.

Regulation

In the United States, the Environmental Protection Agency (EPA) has set standards for THMs in drinking water. The maximum allowable level for total THMs is 80 parts per billion (ppb). Water suppliers are required to monitor their water for THMs and to treat it if levels exceed the standard.

Reduction and Treatment

There are several ways to reduce the levels of THMs in drinking water. One way is to use alternative disinfectants, such as ozone or ultraviolet light, which do not form THMs. Another way is to remove the organic and inorganic matter in water that reacts with chlorine to form THMs. This can be done through coagulation, filtration, or adsorption processes.

See Also

• Water Treatment
• Water Quality
• Environmental Health