Dear Doctor;Sometimes tap water comes chlorinated. I am told this means the water has been treated. Does this mean such chlorinated water is safe for drinking? Are there side effects of chlorine to the body? Jean-Marie, 22. Nyagatare.Dear Jean-Marie, Treated tap water usually is chlorinated. This is done to disinfect the water and make it free from infectious germs which can cause disease in human beings. As per health regulations, Chlorine used for disinfecting water is in amounts which would kill the germs but would be safe for individuals. The health hazards of drinking chlorinated water is it can induce asthma and other allergic reactions in people who are allergic to it. The greatest risk comes from reaction of chlorine with other organic by products present in water.

These disinfection by products, lead to many health hazards like somnolence, liver and kidney toxicity, even heart diseases and cancer. In higher doses there is risk of unconsciousness and death.

However the World Health Organisation recommends that the risks posed by these by products is much less as that caused by  drinking water which can cause infection.