Drinking tea from plastic tea bags can expose you to billions of nano- and microplastics with every sip, putting your health at risk.

Many tea bags contain small amounts of tiny plastic particles called microplastics. When interacting with hot water, they can be released into the tea and end up drunk.

Food, packaging and kitchen utensils are the main sources of plastic pollution, but scientists do not yet know exactly what impact they have on our health.

But they are known to release chemicals called endocrine disruptors, which are thought to disrupt human hormones and increase the risk of certain cancers.

Microplastics can also increase the risk of cancer by interacting with the genetic material in our cells.

Microbiologists at the Independent University of Barcelona (Universitat Autònoma de Barcelona, ​​​​UAB), Spain, recently studied the plastics released by three different tea bags and their effect on human cells.

Finding that commercially available tea bags release huge amounts of plastic particles into hot water when boiled, they experimented with tea bags made from three plastics: polymers called polypropylene, nylon-6 and cellulose.

They found that tea bags containing polypropylene release approximately 1.2 billion plastic particles per drop – or milliliter – of tea. Those containing cellulose release 135 million particles per drop, and nylon-6 releases 8.18 million particles per drop.

The researchers then stained the particles and exposed them to different cells from the human gut to see how they might interact inside the body after ingestion.

After 24 hours, a specific type of digestive cell that produces mucus in the intestines absorbed significant amounts of micro and nanoplastics. The plastics have even found their way into the nucleus of some of these cells, where the genetic material is stored.

This suggests that digestive mucus may play a key role in absorbing micro and nanoplastics into the body before they are transported into the bloodstream and elsewhere in the body.

UAB scientist Alba García-Rodríguez described the research on plastic pollutants as “a very important tool for advancing research on their possible effects on human health.”

The team used a long list of state-of-the-art techniques to track microplastics, including electron microscopes, infrared technology, lasers and nanoparticle tracking analysis.

“The insights gained from this study should inform regulatory policies aimed at minimizing plastic contamination in food contact materials and protecting public health,” the researchers wrote.

Link

Banaei, G., Abass, D., Tavakolpournegari, A., Martín-Pérez, J., Gutiérrez, J., Peng, G., Reemtsma, T., Marc, R., Hernández, A., García-Rodríguez , A. (2024). Tea bag-derived micro/nanoplastics (real-world MNPLs) as surrogates for real-world exposure scenarios, Chemosphere, 368(143736). https://doi.org/10.1016/j.chemosphere.2024.143736