Commercial Tea Bags Release Millions of Microplastics, Penetrating Human Cells

Groundbreaking Study Reveals Health Risks of Plastic Tea Bags

A study by researchers at the Autonomous University of Barcelona (UAB) has revealed alarming findings about the release of microplastics and nanoplastics (MNPLs) from commercial tea bags. Published in the journal Chemosphere, the research demonstrates how these particles can penetrate human intestinal cells, potentially reaching the bloodstream and spreading throughout the body.

Plastic Pollution in Food and Drink

Plastic pollution, particularly from food packaging, is a growing concern for public health and the environment. Inhalation and ingestion are the primary ways humans are exposed to MNPLs, with food and beverages being significant sources.

The UAB research team, part of the Mutagenesis Group at the Department of Genetics and Microbiology, conducted an in-depth analysis of plastic tea bags made from nylon-6, polypropylene, and cellulose polymers. Their findings show that when tea is brewed, these materials release enormous quantities of microplastics and nanoplastics into the infusion.

Shocking Levels of Plastic Contamination

The study quantified the release of MNPLs from various tea bag materials:

• Polypropylene: Released approximately 1.2 billion particles per milliliter, averaging 136.7 nanometers in size.
• Cellulose: Released about 135 million particles per milliliter, averaging 244 nanometers.
• Nylon-6: Released 8.18 million particles per milliliter, averaging 138.4 nanometers.

To achieve these measurements, the researchers used advanced analytical tools, including scanning electron microscopy (SEM), transmission electron microscopy (TEM), and nanoparticle tracking analysis (NTA).

“We have used cutting-edge techniques to characterize these pollutants, providing an important foundation for advancing research into their potential health impacts,” said Alba Garcia, a UAB researcher involved in the study.

Interaction with Human Cells

In a pioneering experiment, researchers exposed human intestinal cells to stained MNPLs to assess their interaction. The results were concerning:

• Intestinal cells that produce mucus showed the highest uptake of MNPLs.
• Particles were observed entering the cell nucleus, where genetic material is stored.

These findings highlight the critical role of intestinal mucus in facilitating the absorption of MNPLs and raise questions about the long-term health effects of chronic exposure to such pollutants.

Call for Action

The researchers stress the urgent need for standardized testing to evaluate MNPL contamination from plastic food contact materials. They advocate for regulatory policies to mitigate this contamination and ensure food safety.

“As the use of plastic in food packaging continues to grow, addressing MNPL contamination is essential to protect public health,” the study concludes.

Implications for Public Health

The research underscores the potential risks of everyday items like plastic tea bags. While more studies are needed to fully understand the health impacts, the findings emphasize the importance of exploring safer alternatives to plastic in food and beverage packaging.