What water can't be drunk?

Raw water, boiling water, aged water. According to Min Fukang.

1, there will be harmful substances such as eggs, parasites and viruses in raw water, which will cause gastrointestinal diseases such as gastroenteritis and dysentery after drinking.

2. Boiled water refers to water that is boiled repeatedly and contains more heavy metals and nitrite. Drinking boiled water for a long time may cause cancer.

3. Aged water refers to water that has been stored for a long time. This kind of water has been stored for a long time, which leads to the deposition and increase of toxic substances and has an impact on people's health.