CHLORINE

As a halogen, chlorine is a highly efficient disinfectant, and is added to public water supplies to kill disease-causing pathogens, such as bacteria, viruses, and protozoans, that commonly grow in water supply reservoirs, and on the walls of water mains and in storage tanks.

Chlorine is highly toxic to kill microbes and prevent the spread of waterborne diseases such as cholera, dysentery, typhoid.

TREATING WATER

The first documented use  to purify the water supply was the use of sand filters.  This dates to 1804, when the owner of a bleachery in Paisley, Scotland, installed an experimental filter, selling his unwanted surplus water to the public.[1][2] This method was refined in the following two decades by engineers working for private water companies, and it culminated in the first treated public water supply in the world in London in 1829.[3][4] This installation provided filtered water for every resident of the area, and the network design was widely copied throughout the United Kingdom in the ensuing decades.

Cholera, typhoid fever, and dysentery killed many people before chlorinating the water.

Permanent water chlorination began in 1905, when a faulty slow sand filter contaminated the water supply and caused a serious typhoid fever epidemic in Lincoln, England.[3]

In 1905 first used in U.S. to treat the water in Jersey city, New Jersey.  (calcium hypochlorite) at doses of 0.2 to 0.35 ppm.

HOW IT WORKS

Chlorine is able to disintegrate the lipids that compose the cell wall and react with intracellular enzymes and proteins, making them nonfunctional. Microorganisms then either die or are no longer able to multiply.

NEGATIVE

Chlorine reacts with naturally occurring organic compounds found in the water supply to produce compounds known as disinfection by-products (DBPs). The most common DBPs are trihalomethanes (THMs) and haloacetic acids (HAAs).

Chronic exposure of both bromoform and dibromochloromethane can cause liver and kidney cancer, as well as heart disease, unconsciousness, or death in high doses

SWIMMING POOLS

No swimming in  shock chlorinated should not be swum in or ingested until the sodium hypochlorite count in the water goes down to three parts per million (PPM) or less.

Also

Hypochlorite is also added to the water supply in fighting bacteria.

CHLORAMINES

The Water Quality Association reports: Chloramines are small, stable molecules with no net charge making them difficult to remove by distillation, reverse osmosis, and ion exchange resins.  However, kdf breaks the bond between chlorine and ammonia (ie chloramine) allowing carbon to readily absorb both. FOAM ADVANTAGE kdf greatly increases the effectiveness. So when foam kdf is combined with carbon, the result is extremely effective chloramine removal – up to 100% in tests.