Drinking water boiled by an electric kettle for a long time is not only poisonous but also carcinogenic? 3 suggestions to listen to
Xiaojiu found that a relative in the family group said that he never used an electric kettle because he was worried about the unsafe stainless steel and manganese poisoning.
As soon as this remark came out, it immediately caused a lot of commotion in the group.
As a health science editor, I can't hold back any longer. Today, I will talk about the water boiled by the "electric kettle". Will the metal exceed the standard? Is there any health hazard if drinking it for a long time?
1. Using a kettle to boil water for a long time will precipitate metal, can it be poisoned or cause cancer?
A kettle is a daily electrical appliance that you will often come into contact with in life. Is there such a risk in an electric kettle using high manganese steel as the liner material?
Let's first understand what manganese is. In fact, it is essentially one of the essential trace elements in the human body . It has multiple functions such as promoting fat and carbohydrate metabolism, calcium absorption, blood sugar regulation, and maintaining brain and nerve function. Once it is missing, it can bring a variety of effects to health, such as affecting neurodevelopment, etc.; but in the same way, if manganese is excessive, it is not good for health, and it can inhibit the absorption of iron. Doing this for a long time can affect the function of the nervous system and increase the risk of diseases such as Parkinson's disease.
However, as long as the average person ensures a normal diet, there will rarely be a "manganese deficiency" situation , and if they do not deliberately supplement manganese, they will rarely overdose.
As for the kettle, it can be mainly divided into "high manganese steel" and "304 stainless steel". What is the difference between the two?
Li Guangqiang, a professor at the School of Materials and Metallurgy of Wuhan University of Science and Technology, said: In fact, the difference between these two kinds of kettles is not too big, but compared with "304" stainless steel, "high manganese steel" reduces the "nickel" content and increases "manganese" , the corrosion resistance is slightly worse, and the appearance gloss is darker, but it has more cost advantages in terms of price.
But no matter what kind, as long as it is produced by a regular manufacturer, the kettle made of "high manganese steel" has no obvious hidden risks and can be used with confidence.
And it should be emphasized that manganese is a highly insoluble element , so manganese in the container material will not easily precipitate. In addition, the absorption probability of manganese by the human body is also very low, only 1% to 5%, and the rest will basically be excreted with the feces after digestion. Therefore, friends who use kettles with high-manganese steel inner liner, do not need to panic. If you use a kettle to boil water for a long time, metal will be precipitated. It is a rumor that it causes cancer.
2. There is scale deposited on the bottom of the pot, is the water still drinkable?
Many people have found that a layer of "white rust" appears on the bottom of a newly purchased kettle after heating, and occasionally a layer of white floating objects is seen on the surface. What's going on? Is this water still drinkable?
The Guangzhou Health and Health Commission conducted an experiment on this. They bought bottled natural water and mineral water in the supermarket, as well as common tap water. They boiled them and poured them into cups to cool down. Finally, they found that both kinds of water appeared. White Float . Subsequently, they searched for professional institutions to conduct professional water quality testing, and found that all water quality data were in line with national standards.
So, what exactly is a white floater?
Simply put, it is the precipitation of calcium and magnesium carbonates . Calcium and magnesium will exist in the form of bicarbonate in water, and when heated, they will form a white precipitate that adheres to the wall of the pot, which is the final scale.
Is drinking this water harmful to the human body?
As long as the tap water is qualified, it will not endanger health. After the scale enters the body, it will be decomposed into calcium and magnesium ions under the action of gastric acid, part of which is excreted from the body, and a small part is absorbed by the human body , but it is not enough to pose a threat to health. Of course, scale is not so "innocent" either. The scale has poor thermal conductivity and can affect the heat transfer of the heated surface, thereby wasting fuel or electricity.
As for the rumor that "drinking boiled water from tap water for a long time will damage the kidneys and easily get kidney stones", there is no scientific basis. Moreover, kidney stones are caused by a combination of factors, such as abnormal metabolism, dietary structure, and love to drink strong tea on an empty stomach. It is not caused by drinking water alone.
Therefore, everyone should treat the problem of scale rationally.
3. Does boiled water have a shelf life? Let it cool down and drink it, is it a chronic poison?
In order to understand the confusion, CCTV-1 "Life Circle" conducted an experiment to explore the accuracy of the statement that "after 16 hours of boiling water, the number of Escherichia coli detected seriously exceeds the standard, and drinking it will harm health".
After the experimenter boiled the tap water, it was divided into 4 parts and placed for 0, 12, 24, and 48 hours, respectively, and then tested. In the end , it was found that the total number of bacterial colonies was 180CFY/ml (the Chinese standard is <100CFU/ml), which exceeded the hygiene of drinking water. In other periods of water, total coliforms, heat-resistant coliforms, Escherichia coli, and total bacterial counts were not detected.
In addition, after the water is cooled, a large amount of nitrate will be produced, which is equivalent to drinking a chronic poison. There is no basis for it. Under normal circumstances, during the process of cooling the boiled water, most of them are in a home environment. At this time, they may be infected by microorganisms. Sex is relatively low, and it is unlikely to produce large amounts of nitrite.
Therefore, drinking boiled water after cooling does not pose too much food safety risk, but it is best not to drink boiled water that has been used for several days . .
Fourth, there are 3 suggestions for electric kettles
As one of the daily necessities, the electric kettle needs to understand some details of its use, so as to drink water better.
1, buy and see the packaging
When buying an electric kettle, you can check the outer packaging. In addition to checking whether it is stainless steel 304, you should also check whether there are signs and words of "implementation standard GB 9684-2011" or "for food contact". If there is no, it is not recommended to buy.
2. Regularly remove scale
For example, wiping with baking soda to remove limescale. Take half a spoon of baking soda, make a paste with water, dip it with a clean rag, wipe the scale in the pot, and then rinse with water.
3. How to choose other electric kettles?
Due to different materials, electric kettles can be divided into three types: glass, ceramics, and folding electric kettles, each with their own advantages and disadvantages. For example , a glass electric kettle is prone to uneven heating and is not resistant to falling. If you want to buy it, it is recommended to look for high borosilicate glass; if the ceramic electric kettle is colored, it may precipitate heavy metal toxic elements. It is recommended to choose the inner wall without color and pattern. ; The folding electric kettle is small and easy to carry, and the purchase should look for food-grade silicone (or PP material).
Summary: As long as you choose a regular manufacturer to produce a kettle with 3C certification, you can use it with peace of mind. There are many kinds of kettles, and you can choose according to your own needs.
References:
[1] "Electric kettle makes people stupid? Will "high manganese steel" damage memory? 》. Nutshell.2016-03-24
[2] "[Reminder] Is the water boiled by a stainless steel electric kettle "toxic"? The truth is finally clear". People's Daily. 2016-03-27
[3] "Revelation | What is the white floating thing after the tap water is boiled? Is it still drinkable? The truth is →". Guangzhou Health Commission. 2022-05-10
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