What are the hazards of excessive chlorine in tap water?

- Feb 13, 2019-

The chlorine in the tap water comes from the sterilization process of the water after the water plant takes water from the natural water source.

A common disinfectant is chlorine.

After the chlorine gas is dissolved in water, it is further reacted to form hypochlorous acid. (At this time, if the hardness of water is relatively large, a so-called bleaching powder component is produced due to the presence of calcium ions, but in fact it only sounds terrible. On the one hand, calcium hypochlorite is a strong electrolyte.

There are no independent calcium hypochlorite molecules in the water. On the other hand, hypochlorite itself is unstable. It is impossible to whiten the color of water after a long time of transport. 

The most likely reason for the color whitish is that the bubble content in the water is too large, we can rest assured that chlorine can not be chlorine, because chlorine is yellow-green, and it is really tired.

Strongly oxidized hypochlorous acid kills most pathogenic microorganisms in water

Chlorine is usually supersaturated in tap water. The purpose is to allow the tap water to contain a certain amount of chlorine (residual chlorine) in the water for a long time from the transportation process factory of the wa to the home of the residents.

Chlorine is biotoxic and will not be used as a fungicide, but its toxicity is relatively easy to control. Remember the experience of sniffing chlorine in a high school lab?

As for the biological toxicity of chlorine,

Introduction to Toxicology

If you don't like the feeling of chlorine in tap water, then boil it or put it in the sun for a while.

However, I am worried that the effect is very limited. After all, the chlorine content in tap water is actually very negligible.

 PS I think the smell in the news should not come from chlorine, or mainly from chlorine. The reporter personally contacted the relationship between chlorine content and odor. In fact, the smell of raw water may be the main one.

At that time, the water plant should take deodorization measures, such as putting activated carbon, but I don't know if it is because of the high cost and the water quality is not big.