Concerned about the health: drink five water should carefully 

    Re-boiling water will cause nitrite content in water exceeded. Is well known that excessive or excessive nitrite in water can cause people to different degrees, fatigue, weakness, drowsiness, coma, general bruising, blood pressure, abdominal pain, diarrhea, vomiting, lack of malignant disease can cause. Open water pollution prevention is simple: a firm to eliminate the reuse of water, repeated boiling. With particular attention to the following reference to the water undrinkable.
1. Stoves burning all night or for a long time, drinking is not the time of lukewarm water;
2. Automatic re-boil water heater in the water overnight;
3. After the residue repeatedly boiled water;
4. Packed in thermos of boiling water the same day China-Africa;
5. Steamed dishes and other food remaining water.