Boiling Water Repeatedly, Is It Really Dangerous For Health?

Illustration of boiling water (Freepik)

JAKARTA - Recently, news has circulated on the internet that the mention of boiling the same water repeatedly in the cassava can endanger health. Reportedly, the boiled water will continuously bind harmful minerals, metals, and chemicals. But, is the news true?

A civil engineering expert,Faisal Hai, who is also a professor and principal of a civil engineering school at the University of Wollongong, spoke about the matter. To The Conversation, he explained that the claim was groundless.

"To characterize the substance in water, you need to evaporate some of the liquid while the chemicals remain lagging behind," said Professor Hai, quoted from the Cambridge News page.

"Water evaporates at any temperature, but most of the evaporation occurs at boiling points, when water turns into vapor. As long as it boils, some volatile organic compounds may come out into the air, but the amount of inorganic compounds (such as metal and salt) remains unchanged," he continued.

So while the concentration of inorganic compounds may increase slightly as water evaporates, evidence suggests that it doesn't happen to a dangerous level.

"Say you boil one liter of water in the morning, and your water contains 1mg of fluoride per liter," said Professor Hai, explaining as an example.

"Then, you make a cup of tea with 200 ml of boiling water. In the afternoon, you boil the remaining water to make another cup of tea," he continued.

On both occasions, if the warm-up is stopped as soon as it boils, the water loss due to evaporation will be small, and the fluoride content in each cup will be the same.

Even if you let the water boil longer when pouring water into a second cup of tea, up to 100 ml of water evaporate, the amount of fluoride consumed with a second cup (0.23 mg) will not be significantly higher than the fluoride consumed with the first cup of tea (0.20mg).

The same applies to minerals or other organic materials that may be contained in water. Taking an example, Professor Hai explains that you should reduce 20 liters of water to only 200 ml left to reach the level.

"Practically that's not possible, most of the electric cassava is designed to boil briefly before it turns off automatically," he said.

"As long as the water you use is in accordance with drinking water guidelines, you can't really put it to a dangerous level in the cassava," he added.

Furthermore, small mineral confinement, or the loss of dissolved oxygen from water during boiling can affect the taste for some people, although there are many other factors that contribute to the taste of water.

"The bottom line is that as long as the water in your cassava is initially in accordance with safe drinking water guidelines, the water will remain safe and fit for drinking even after being boiled repeatedly." he continued.