Chlorine is a highly efficient disinfectant, and it is added to public water supplies to kill disease-causing bacteria that the water or its transport pipes might contain.  Chlorine however is a carcigenous and absorbed by the body.

Chlorine has been hailed as the savior against cholera and various other water-borne diseases, and rightfully so, says Steve Harrison, president of water filter maker Environmental Systems Distributing. Its disinfectant qualitiesÉhave allowed communities and whole cities to grow and prosper by providing disease-free tap water to homes and industry.

But Harrison says that all this disinfecting has not come without a price: Chlorine introduced into the water supply reacts with other naturally-occurring elements to form toxins called trihalomethanes (THMs), which eventually make their way into our bodies. THMs have been linked to a wide range of human health maladies ranging from asthma and eczema to bladder cancer and heart disease. In addition, Dr. Peter Montague of the Environmental Research Foundation cites several studies linking moderate to heavy consumption of chlorinated tap water by pregnant women with higher miscarriage and birth defect rates.

A recent report by the non-profit Environmental Working Group concluded that from 1996 through 2001, more than 16 million Americans consumed dangerous amounts of contaminated tap water. The report found that water supplies in and around Washington, D.C., Philadelphia and Pittsburgh in Pennsylvania, and the Bay Area in California were putting the greatest number of people at risk, although 1,100 other smaller water systems across the country also tested positive for high levels of contaminants.

Dirty water going into the treatment plant means water contaminated with chlorination byproducts coming out of your tap, said Jane Houlihan, EWG's Research Director. The solution is to clean up our lakes, rivers and streams, not just bombard our water supplies with chlorine.

Studies in the United States, Canada and Norway have linked chlorine byproducts in ordinary tap water to higher risks of miscarriages and stillbirths in pregnant women and increased incidences of bladder and colon cancer.

Dr. Herbert Schwartz of Cumberland County College in Vineman, N.J. says:

 "Chlorine has so many dangers it should be banned. Putting chlorine in the water supply is like starting a time bomb. Cancer, heart trouble, premature senility, both mental and physical, are conditions attributable to chlorine treated water supplies. It is making us grow old before our time by producing symptoms of aging such as hardening of the arteries."

Chlorine is, essentially, bleach.  And what comes out of most municipally delivered faucets is, quite actually, a mild bleach solution. But Chlorine is the cheapest way to disinfect, and who wants to have their utility or taxes raised?