Share an article from Professor Qi from Xuanwu Hospital in China:
When steaming food be sure the lid is open to boil the water first, then add to the steaming food, close the lid!
No wonder more and more people with cancer. With pot cooking something, be sure to use water, or filtered water. Because if the direct use of tap water, tap water has chlorine, then after heating, because the lid is covered, the chlorine is all covered in food, so be sure to use boiled water or filtered out chlorine water to steam things. Because chlorine is carcinogenic hazard. This is really important!
Even if only steamed buns, should have this knowledge. When steaming your food, make sure you open the lid to boil the water first. If water is used straight from the tap, your food will be contaminated by absorbing all the cancer causing chlorine upon heating which is a serious health hazard.