By According to Columbia University's Health (USA) found that people who consume chlorinated water, a 44% increased risk of cancer of the gastrointestinal tract and bladder cancer compared with those who use non-chlorinated water, in addition, chlorinated drinking water contributes to high blood pressure, atherosclerosis and ischemic heart. Most people, in order to reduce the risk of poisoning water water, boil it before drinking. Boiling water actually causes the death of some bacteria. But it is proved that boiling does not kill all harmful microorganisms. For example, the causative agent of viral hepatitis dies at higher temperatures, Prions – pathogens of 'mad cow' – not die even when boiled for 7 hours. In addition, boiling in no way reduces the water content in the salts of heavy metals and organic pollutants. Exceeding the allowable standards content in the tap water of heavy metals such as lead, mercury, cadmium, zinc, nickel, chromium, causing atherosclerosis, polyneuritis, hypertension, bone marrow, loss of visual acuity.
But the most dangerous thing is that when boiled chlorinated tap water, chlorine and its derivatives interact with an unknown amount of organic matter to form carcinogenic trihalomethanes, which in turn is one of the reasons cancer. Ie while boiling, 'situation' in the tap water only gets worse. The use of household filters does not solve the problem of obtaining clean drinking water because they clean the water on only two or three types of pollutants (the remnants of rust, sand, etc.) without actually clearing it from the others.