Surprisingly simple way to remove microplastics from your drinking water

Microplastics sound like a distant environmental problem, but they’re much closer than most of us realise. Tiny plastic fragments are already showing up in our food, and especially in our drinking water. The good news? Scientists say there’s a very simple thing you can do at home to reduce how much of it you consume.In 2024, researchers in China found that boiling tap water and then filtering it can remove a significant amount of nanoplastics and microplastics. The team tested both soft water and hard tap water, adding known amounts of plastic particles before heating the water and filtering out what formed afterward. “Tap water nano/microplastics (NMPs) escaping from centralized water treatment systems are of increasing global concern, because they pose potential health risks to humans via water consumption,” the researchers wrote in their paper.The results were striking. In some cases, up to 90 percent of microplastics were removed using nothing more than boiling and filtering. How effective it was depended on the type of water.The method works especially well with hard tap water, the kind that leaves chalky residue inside kettles. When hard water is heated, calcium carbonate (limescale) comes out of solution and forms a crust. That crust traps plastic particles as it forms.“Our results showed that nanoplastic precipitation efficiency increased with increasing water hardness upon boiling,” the team wrote. “For example, from 34 percent at 80 mg L−1 to 84 percent and 90 percent at 180 and 300 mg L−1 of calcium carbonate, respectively.”Even soft water showed benefits. About 25 percent of microplastics were removed, simply through boiling.Once the water cools, those lime-coated plastic bits can be removed using something as basic as a stainless steel mesh strainer, like the kind many people already use to strain tea.“This simple boiling water strategy can ‘decontaminate’ NMPs from household tap water and has the potential for harmlessly alleviating human intake of NMPs through water consumption,” said biomedical engineer Zimin Yu of Guangzhou Medical University, who led the study.The researchers didn’t stop there. To really test the method, they added even higher concentrations of nanoplastics, and still saw large reductions.“Drinking boiled water apparently is a viable long-term strategy for reducing global exposure to NMPs,” Yu and his colleagues wrote. They also noted that while boiling water is common in some regions, it’s still seen as a local habit rather than a global health practice.This matters because microplastics are everywhere. They come from synthetic clothing, kitchen tools, personal care products, packaging, and they don’t fully break down. Instead, they fragment into smaller and smaller pieces that linger in the environment and in our bodies.A 2025 literature review from the University of Texas at Arlington found that drinking water may be one of the main ways humans are exposed to microplastics, partly because wastewater treatment plants still don’t remove them effectively.Globally, about 9 billion metric tons of plastic have been produced since mass plastic manufacturing began. Much of it has degraded into microscopic particles that now circulate through air, soil, food, and water.While scientists are still studying exactly how harmful microplastics are, they’ve already been linked to changes in the gut microbiome and increased antibiotic resistance. At the very least, they’re not something our bodies are designed to handle.The researchers behind the boiling-water study say more work is needed, but the takeaway is refreshingly practical.“Our results have ratified a highly feasible strategy to reduce human NMP exposure and established the foundation for further investigations with a much larger number of samples,” Yu and colleagues concluded.