Boiling water is not necessarily clean. In case of serious water pollution, various problems may occur, such as chlorine residue in tap water and iron residue during transportation. Hot water can kill bacteria, but it can not remove these harmful substances. Long term drinking is also harmful to the body.
Nowadays, many people have a misconception that drinking cold water is easy to get sick. After boiling the water, it won't kill the bacteria and microorganisms. In fact, this is not comprehensive. Why do you say so? This is a good way for slightly polluted water quality, but at present, water pollution is relatively serious and may face various problems.
Current water supply companies use chlorine to sterilize and remove odor, but chlorine is usually left in it, which makes the tap water taste like disinfectant. After heating this water, it is easy to produce chloroform and other cancer inducing substances. When transported through the pipeline, if the water pipe is iron, it will age and rust after long-term use, These rust will also be mixed with tap water, and long-term drinking will cause harm to the body.
Generally, boiling water can kill bacteria and so on, but it can not remove the heavy metals, toxic substances and carcinogens in the water. In the process of boiling water, the water will evaporate, which will lead to the increase of metal concentration. Therefore, boiling water is not necessarily very clean and harmless.