Why must chlorine be removed from drinking water?

What is chlorine?

Chlorine is a chemical element with symbol Cl. It is a pale-green poisonous gas and is one of the halogens found in group seven of the Periodic Table. The Swedish chemist Carl Wilhelm Scheele discovered chlorine in 1774, but it was Sir Humphrey Davy who gave it its name. It has an unpleasant, suffocating odour and forms part of table salt as the chloride ion. Chlorine gas with formula Cl2 combines readily with other elements. At a temperature of 10oC one litre of water can dissolve 3,1 litres of gaseous chlorine.


Chlorine gas is a powerful oxidizer and its first use was to bleach textiles in 1785. Sodium hypochlorite was developed from chlorine in the French town Javel which became a popular bleaching agent in most homes with the same name. Chlorine is also an inexpensive and very effective water disinfectant used to treat drinking water, swimming pools and abattoirs.   used in bleaches and to disinfect drinking water and cleaning swimming pools. It is also used in paper manufacturing, insecticides, paints, petroleum, plastics, solvents, textiles and medicine.

Chlorine became the first killing agent to be employed during World War I. On 22 April 1915 Germany dropped 180 tons of chlorine gas on opposing trenches in Northern France. This killed 5 000 men and scorched the lungs of 15 000 French and British troops. After this attack chlorine was used by both sides as a chemical weapon. During the Iraq War in 2007 insurgents used chlorine gas as a chemical weapon to create widespread panic.


Chlorine is a toxic gas and strong oxidiser that can damage the respiratory system and cause pulmonary oedema. The gas can also cause eye and skin irritation. In 1904 chlorine became the standard method of water disinfection. It is not only very effective, but also cheap. Initially, chlorine was considered a wondrous blessing. Prior to its use, millions of people suffered from waterborne diseases like cholera, typhoid fever, dysentery, and other pathogens. In the 1960s it became evident that chlorine combines with organic substances in water to produce drinking water by-products such as trihalomethanes and dioxins which have a carcinogenic effect on human health. Chlorine is, essentially, bleach. Chlorinated tap water is nothing else but a mild bleach solution which is not healthy to drink.

Everybody wants to write on white paper and swim in bacteria-free water, but few of us realize the adverse effect chlorine has on life. Residual effects from chlorine are becoming a health hazard. The American Public Health Association urged the American paper industry to stop using chlorine. The U.S. Environmental Protection Agency (EPA) has found dioxin (a toxic by-product of chlorine) to be 300,000 times more potent as a carcinogen than the insecticide DDT.

The paper industry uses large quantities of chlorine to bleach the paper to make it white. The wastewater containing dioxins is then dumped and contaminates ground and surface water. Dioxins are highly toxic and carcinogenic.

In his book, Coronaries/Cholesterol/Chlorine (published in 1969) Dr Joseph Price writes: We are learning the hard way that all the time we thought we were preventing epidemics of one disease, we were creating another. Two decades after the start of chlorinating our drinking water the present epidemic of heart trouble and cancer began.

What other experts say about chlorine

  • According to the U.S. Council of Environmental Quality: Cancer risk among people drinking chlorinated water is as much as 93% higher than among those whose water does not contain chlorine.
  • Dr. Joseph M. Price MD: When chlorine is added to our water, it combines with other natural compounds to form Trihalomethanes (chlorination by-products), or THMs. These chlorine by-products trigger the production of free radicals in the body, causing cell damage.
  • Dr. Joseph M. Price MD: Cancer risks among people drinking chlorinated water are 93% higher than among those whose water does not contain chlorine.
  • U.S. NEWS & WORLD REPORT – July 29 1991 Is Your Water Safe? – The Dangerous State of Your Water: A long hot shower can be dangerous. The toxic chemicals are inhaled in high concentrations.
  • AMERICAN JOURNAL OF PUBLIC HEALTH – Dr. Halina Brown:       Showering is suspected as the primary cause of elevated levels of chloroform in nearly every form because of the chlorine in the water.
  • WATER CAN UNDERMINE YOUR HEALTH – Dr. N.W. Walker – Chlorine is the greatest crippler and killer of the modern times. While it prevented epidemics of one disease, it was creating another. Two decades ago, after the start of chlorinating our drinking water in 1904. The present epidemic of the heart trouble, cancer and senility began.
  • U.S. COUNCIL OF ENVIRONMENTAL QUALITY – Drinking tap water that is chlorinated is hazardous, if not deadly to your health.

In their book, One Hundred Years of Water Chlorination, chemists John Ashton and Dr. Ronald Laura look at another side of bathing in chlorinated water: Gasses are as a rule less soluble in hot water, and when water is heated or boiled dissolved gasses are released. Boiling water is, as we noted earlier, a way in which the free chlorine content in water is greatly reduced, the chlorine escaping into the air. Who hasn’t noticed at least a faint smell of chlorine while taking a hot shower? What concerned the above researchers is how the concentration of chlorine in the air steadily increases as a result of the confined space within an enclosed shower stall or tub; especially one with poor ventilation. According to Ashton and Laura, The olfactory threshold for chlorine is about 3.5 ppm (parts per million) so when we can smell chlorine the concentration is already above this level. The lethal concentration for ten-minute exposure is about 600 ppm and we suggest that regularly taking hot showers with chlorinated water could pose a health risk.

The effectiveness of chlorine to kill living organisms can not be denied. It is both efficient and inexpensive. But, before using chlorinated water for cooking or drinking purposes at the point of use (POU), it should first be removed, as the plastic bag is removed from bread before ingestion. The plastic is for hygiene, not for consumption.



The Light Party:

Health Wealth Happiness:

Dr John’s Health File:

Optimal Life Centre:

Price, J. M. Coronaries/Cholesterol/Chlorine, Jove Book, Alta Enterprises, 1969.

Walker, N.W. Water can undermine your health, Norwalk Press, 1974.