Study Finds About 240,000 Plastic Particles in Each Litre of Bottled Water

Study using laser imaging finds an average of 240,000 plastic particles per litre in popular bottled water brands, most of them nanoplastics. Researchers at Columbia University applied Stimulated Raman Scattering microscopy, a technique that spots particles far smaller than older methods. Earlier estimates of only a few thousand particles per litre now appear to be severe under‑counts. The study also shows that simply opening and closing a bottle cap creates friction that releases tiny fragments, adding to contamination from manufacturing, bottling and environmental sources. Ankur Garg, country director of Evidence Action/EAII, says some particles come from the water itself while others shed from the bottle or cap during production and transport. He notes the World Health Organization says long‑term health effects are still unclear. ScienceInsights reports most microplastics pass through the gut and exit in stool, but nanoplastics are small enough to cross the intestinal wall into the bloodstream. Research confirms plastic can reach circulatory tissues, yet scientists cannot yet pinpoint which sizes cross most easily, how much builds up, or the dose that harms health. Dr Palleti Siva Karthik Reddy warns that boiling does not remove microplastics; heating may even increase release of particles and chemicals, especially under prolonged high temperatures. Advanced filtration such as reverse osmosis or fine microfiltration can capture a share of the smaller particles, though performance varies.

Context

Microplastics have been detected in many foods and drinks, raising public concern. The gut barrier generally blocks larger fragments, but nanoplastics can slip through, prompting calls for better waste management and water protection measures.