The public water filtration system used in cities throughout the United States uses chlorine to disinfect the water. Chlorine has been used for this purpose for over 100 years and has been effective in killing the bacteria which cause typhoid, cholera and dysentery.

Although it performs an essential function in the water filtration process, chlorine does have some adverse effects on our health. While the public authorities claim that the amount of chlorine in drinking water is entirely safe, recent studies have shown that this may not be entirely true.

Use of chlorine in drinking water has been linked to various forms of cancer and, because of its corrosive action on the arteries, to the build up of cholesterol leading to heart disease.

Writing in London's Daily Telegraph, Roger Highfield, the science editor, revealed that babies born in areas where drinking water is heavily disinfected with chlorine are at double the risk of heart problems, cleft palate or major brain defects according to a study carried out at Birmingham University.

The researchers found that expectant mothers were at risk not only from drinking the water, but also from bathing, showering or even standing near steam from a boiling kettle.

It is possible, with time, that better alternatives to chlorine disinfection will be used in the public water filtration system. Some countries have already started using more technologically advanced systems. But they are expensive and while the public authorities continue to deny that there is a problem, they are unlikely to consider it a worthwhile investment of public money.

Although chlorine is likely to be used for the foreseeable future in the public water supply, that does not mean that we have to allow the chemical to enter our homes. A house water filtration system that removes chlorine and chlorine by-products known as THMs is both available and affordable. The system has been praised by the EPA as the best technology available.

In the past, when people thought of a whole house water filtration system, they thought of reverse osmosis. But reverse osmosis is old technology. It is one step in the complicated process used at public water treatment facilities. It does not block chlorine or anything lighter than water. Equally it does de-mineralize the water and that's also bad for your health.

The best water filtration system on the market de-chlorinates, but does not de-mineralize. Instead, it uses an advanced ion exchange system to balance mineral content and pH level. Water from the system is neither too alkaline nor too acid. "Hard" minerals that used to require water softeners can be "transformed" into softer minerals that will not damage your pipes or build up on your fixtures.

The newer systems do not require an additional source of energy, as the reverse osmosis unit did. They just make use of the water pressure already found in your home. Water flows through a number of different filters and chambers where chlorine and other chemical contaminants are removed. Lead and chlorine resistant bacteria are also removed. So, you end up with water the way that it should be, natural and pure.