What Happens When You Reboil Water: Facts About Drinking Water Safety

What Happens When You Reboil Water: 

Facts About Drinking Water Safety

Ensuring the safety of the water we consume is crucial, and reboiling water has been a subject of concern for many. 

Let’s uncover the truths about reboiled water and how it impacts our health.

1. Does Reboiling Water Make It Unsafe?

Reboiling water can slightly concentrate minerals and impurities such as nitrates, arsenic, or fluoride, depending on the water quality. However, in clean drinking water, these increases are negligible and do not pose a significant health risk. The safety concern arises only if the source water is already contaminated.

Through testing, we’ve observed that prolonged boiling or frequent reboiling of tap water can convert nitrates into nitrites, which some studies suggest are carcinogenic.

For example, reboiling bottled water up to 20 times increased nitrite levels to 2.1 µg/L, exceeding the standard by 0.1 µg/L. After 181 times reboils, nitrite levels rose fivefold to 3.53 µg/L. While this sounds alarming, it’s far below the nitrite levels found in everyday foods like ham, which can legally contain up to 30,000 µg/kg.

In fact, even water boiled 40 times contains nitrites at no more than 3% of the recommended daily intake by the Joint FAO/WHO Expert Committee on Food Additives (JECFA). Most household kettles have a capacity of 700 ml to 2 L, making it unlikely for anyone to reboil water frequently enough to pose a health risk.

2. Does the Scale at the Bottom of My Kettle Pose a Health Risk?

In areas with hard water, rich in calcium and magnesium ions, repeated boiling can cause scale buildup. While this may look unappealing, it poses no significant health risks.

Even if you drank 2 liters of heavily scaled water daily, the calcium intake would still be far lower than that from a single glass of milk.

The only downside?

The taste might not be good enough.

3. Do I Need a Kettle With a Dechlorination Feature?

Tap water in most urban areas is disinfected with chlorine to ensure safety during transport to your home. Residual chlorine is regulated to remain above 0.05 mg/L at the tap.

The chlorine smell you may notice comes from this residual chlorine, which varies depending on your distance from the water treatment facility. Boiling tap water with the lid off for a few minutes allows the chlorine to evaporate naturally.

Kettles are marketed as having a “dechlorination” function, which simply extends the boiling time, offering no advantage over standard kettles. Certainly, it is more reassuring to some extent, providing emotional value.

4. How Do I Choose the Right Kettle Size for My Needs?

For Travel:

Travel kettles with capacities between 350 ml and 650 ml are ideal.They’re as compact as traditional thermoses but portable, heat-resistant, and capable of boiling water directly. This makes them increasingly popular for business trips and vacations.

HCK-01 350ML Travel Kettle

FZB-CP01 650ML Travel Kettle

For Home Use:
For families, a 1.5 L to 2 L kettle is a practical choice. These kettles can quickly boil enough water for everyone, making them perfect for household use.

W181 Electric Kettle

W20 Electric Kettle

5. Why Choose Our Kettles?

At our factory, we design kettles with features to meet diverse needs, ensuring safety, convenience, and durability. Whether you're looking for compact travel kettles or larger family-sized options, we offer customization options to match your preferences.

Ready to ensure water safety while impressing your customers?

Contact us today to learn more about our innovative kettles!