Micro-organisms are present almost everywhere in the atmosphere in air, water. There are many of them which are known to cause diseases in human and some are not. These micro-organisms are known as Pathogens. These pathogens causes waterborne disease which is transmitted through drinking water distribution system.

There are various methods of disinfection used to kill or inactive the pathogens in order to eradicated water borne diseases. Water treatment process such as sedimentation, filtration, chlorination and coagulation are on the list used for disinfecting the water.

In some situations, it may be problematic to disinfect water by chlorination process. The naturally organic compounds react with the chlorine in the water supply creating compounds known as disinfection-by-products The common DBPs produced are Haloacetic acids (HAAs) and Trihalomethanes (THMs).Trihalomethanes are the main disinfectant which is responsible for health hazards. The duration of the exposure to the chemicals and the amount of THMs intake can decide the level of effects on the body. Bromoform present in the THMs can slow down the regular brain activity showing symptoms such as sedation or sleepiness. Chronic exposure of bromoform can cause kidney and liver cancer as well as heart disease, unconsciousness or death in case of higher doses. Due to the property of carcinogenity of these compounds, the drinking water regulations across the world require regular monitoring of these compounds in the large chlorination plant of water systems.

Chlorination process is a very popular and effective method of water disinfection which has been used for many years for killing bacteria and viruses. Many communities have become hesitant in the continuation of this process with the concern about trihalomethanes, a carcinogenic disinfection by-product. It continues to be the most popular, dependable, and cost-effective method of water disinfection alth