For many, a cup of tea is the perfect way to start the day or unwind in the afternoon. Known for its health benefits, tea is daily a staple in several households. But, a recent study has revealed a surprising hidden risk of drinking tea: microplastics leaching into your drink from the tea bags themselves.

The researchers analyzed tea bags made out of different materials such as nylon-6, polypropylene, and cellulose and found that a single tea bag can release more than 8 million nanoplastic particles into the drink during steeping. Among these materials, tea bags made from polypropylene released the highest number, about 1.2 billion particles per milliliter, according to the results published in Chemosphere.

"We have managed to innovatively characterize these pollutants with a set of cutting-edge techniques, which is a very important tool to advance research on their possible impacts on human health," said Universitat Autònoma de Barcelona researcher Alba Garcia in a media release.

While the findings are startling, they align with previous studies that have shown how a combination of plastics and high heat can cause microplastics to leach into food and drinks.

"The polymer composition of MNPLs (micro/nanoplastics) significantly influences their biological interactions, leading to varied targeting and effects on organs, tissues, and cells. These differences can result in specific accumulation patterns, toxicity profiles, immune responses, and long-term health effects such as genotoxicity and carcinogenicity," the researchers wrote.

The latest study also examined how different types of intestinal cells respond to nanoplastics, noting that some absorb more particles than others. In mucus-producing cells, the absorption levels were sufficient for the plastics to reach the cell nucleus.

Based on the findings, researchers emphasizes the need for consistent methods to measure how micro and nanoplastics are released and their potential toxic effects. They also suggest that the regulatory policies should focus on reducing plastic contamination in materials that come into contact with food.

"Overall, our findings contribute to a growing body of evidence on the pervasive nature of plastic pollution and its potential implications for human health. As the usage of plastics in food packaging continues to rise, scientific research and policymaking must address the challenges posed by MNPL contamination to ensure food safety and consumer well-being," the researchers added.

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