New research from the University of Birmingham has found that hot tea and coffee served in disposable cups contain the highest concentrations of microplastics among common drinks. The study, believed to be the first of its kind, tested 155 soft drinks from popular UK brands purchased in 2024, including hot and iced tea, hot and iced coffee, juices, energy drinks, and soft drinks.
The team found that hot tea in disposable cups averaged 22 microplastic particles per cup, compared to 14 per cup in glass cups. More expensive teabags leached the greatest amount of plastic, averaging 24 to 30 particles per cup. For hot coffee, the researchers said their findings strongly suggest that the disposable cup material is a primary source of microplastics.
Iced versions of tea and coffee contained significantly fewer microplastics, indicating that high temperatures and processing methods contribute to the levels found. The study also revealed that microplastics were present in all cold and hot drinks tested, with the authors stating that “assessment of exposure via drinking water only may substantially underestimate the risk.”
Lead author Professor Mohamed Abdallah noted that people do not only drink water, and that other sources like tea and coffee are substantial. He called for legislative action from governments and international organisations to limit human exposure to microplastics, which are “everywhere.” The research serves as a critical step towards better understanding microplastic exposure in real-life scenarios and advocates for more comprehensive studies for accurate risk assessment.
