Boiling tap water could remove most microplastics, study finds

Tiny plastic fragments, known as microplastics and nanoplastics, are increasingly turning up in our food, drink, and even inside our bodies. Studies show they can damage the gut microbiome and may contribute to antibiotic resistance.

Now, researchers in China have found a surprisingly simple way to cut down on how much of this plastic we consume every day: boiling tap water.

Scientists from Guangzhou Medical University and Jinan University tested tap water by adding plastic particles to both soft water and hard water (which contains more dissolved minerals like calcium carbonate).


When the water was boiled, many of these particles stuck to limescale deposits, the chalky buildup you often see in kettles, before being filtered out.

How effective is it?

The results were promising. Up to 90 per cent of microplastics were removed in hard water, and even in soft water, about 25 per cent of particles were filtered out. The removal rate increased with higher mineral levels since more limescale formed to trap plastics.

A simple tea strainer or mesh filter was enough to catch the contaminated limescale.

Why boiling works

As water heats up, calcium carbonate comes out of solution and forms solid deposits. These crusty buildups act like glue, pulling plastic fragments out of the liquid.

The researchers note that people may unknowingly be protecting themselves from plastic exposure in regions where drinking boiled water is already a tradition.

While modern filtration systems are costly and not always effective against microplastics, this method requires nothing more than a kettle and a filter, tools most households already have.

“Drinking boiled water apparently is a viable long-term strategy for reducing global exposure to NMPs,” the team wrote in their study, published in Environmental Science & Technology Letters.

Scientists caution that more research is needed to understand the full health impact of microplastics. Still, boiling water could be one of the easiest and cheapest ways to limit daily intake.