ABSTRACT
The Environmental Protection Agency has set an maximum contaminant levels (MCLs) of 0.10 mg/L for total trihalomethanes. This MCL, based primarily on treatment capabilities, was established as an Interim National Primary Drinking Water Regulation and is under reevaluation. Chloramine is also used as an alternative to chlorine for disinfection of drinking water. Trihalomethanes (THMs) present in drinking water include chloroform, bromoform, bromodichloromethane, and dibromochloromethane. These compounds are formed from the reaction of chlorine with organic matter such as humus, fulvic materials, and amides present in the water during the disinfection process. THMs one family of the disinfection by-products, are regulated. The interrelationships between the beneficial uses of disinfectants and the potential health concerns stemming from disinfection by-product residues are being considered simultaneously as the regulatory policy is being developed. Major issues to be addressed include the potential relationship of the three main disinfectants—chlorine, chlorine dioxide, and chloramine—to cardiovascular disease.
