A water kettle is one of the essential appliances found in most homes, as it is indispensable for preparing hot drinks.
However, one question remains that is controversial: if we want to make tea, can we use the water left in the kettle from the previous time, or is it better to throw it away and fill the kettle with new water?
It is known that boiling water helps to eliminate most microorganisms, but on the other hand, claims are circulating that repeatedly boiling water leads to the accumulation of harmful substances, prompting some to empty the kettle after every use.
To clarify this issue, it's essential to understand the composition of tap water and what happens to it when it's boiled. Tap water typically contains dissolved salts and minerals, and its hardness varies from city to city and country to country, but it must meet established health standards and regulations. Therefore, boiling it once or several times does not make it harmful to health, as the concentrations of chemicals remain very low and do not reach levels that pose a health risk. During boiling, some volatile organic compounds may evaporate, while the amount of inorganic compounds, such as minerals and salts, remains relatively unchanged.
As for the taste of boiled water and beverages made from it, the effect of reboiling depends largely on the local water source. Some people may notice a slight change in taste due to a small increase in mineral concentration or a decrease in the amount of dissolved oxygen in the water.
In general, if the water used in the kettle has met drinking water safety standards from the beginning, it remains safe and drinkable even after being boiled several times.
