Can’t we drink well water even after it’s been boiled for a long time?
Thread Content
In the countryside, people can drink the water from their own wells, but the students who come from cities don’t drink it. So I boil it for them; I get so busy chatting that it takes a long time to boil it, and they say they still can’t drink it. Is that really the case? Those useful components are gone; what harmful components have appeared instead? Last edited by Welcome on 2009-4-2 09:22]
Drinking boiled water has become a common habit in people’s lives, but there are several types of boiled water that should not be consumed. One is water that has been boiling on the stove for a long time ； The second method is to put water in a thermos for a few days ； The third method is to repeatedly boil the remaining water in a boiling pot ； The fourth is the \"waste water\" left after steaming rice. There are mainly two reasons why these types of water should not be consumed. First, the levels of heavy metals such as calcium, magnesium, and chlorine in water that has been boiled repeatedly increase; drinking such water over a long period can lead to kidney stones. Secondly, the levels of nitrite in these types of water tend to increase, and consumption of such water can lead to difficulties in oxygen delivery in the blood. Moreover, in the intestines, nitrites readily react with secondary amines to form potent carcinogens such as nitrosamines, causing greater harm to the human body. It is best to boil the water for 2–3 minutes. When the temperature of tap water treated by chlorination reaches 100°C, after 3 minutes, the level of halogenated hydrocarbons drops to 9.2 mg per liter, and that of chloroform drops to 8.3 mg per liter – both values are within the standard range. If the water continues to boil, these two substances will become increasingly scarce, while the amount of other non-volatile substances in the water increases, which is also harmful to humans.
Generally, well water is hard water, containing large amounts of calcium and magnesium ions; it cannot be drunk directly. However, after being softened, it can be consumed. I’ve heard that it can lead to the formation of stones. After water is boiled repeatedly, the concentration of nitrites in it increases, and nitrites are carcinogenic substances
So there are so many scientific principles behind drinking water, huh