Green Tea: Is It Really The Healthier Option?

While, technically, it is, but the packaging might make it harmful for us. As per a November 2024 study published in Chemosphere, researchers tested three different brands of tea bags for exposure of microplastics, which are also degraded plastic bits that do not breakdown and found that it could impact human health.

What were the findings?

The team found that brewing tea in polypropylene, essentially plastic bags, or a common tea bag material actually released over a billion particle per milliliter of tea. In fact, what we think as the paper bags, made of cellulose and mesh nylon bags also shed millions of plastic particle per milliliter.

John Meeker, a professor of Environmental Health Sciences and Global Public Health at the University of Michigan School of Public Health said finding such high amounts of micro and nanoplastics in a product that is supposed to be consumed is a cause of concern.

How was the study conducted?

The researchers first extracted plastics from brewed tea and then exposed them to human intestinal cells that absorbed the plastic particles. It showed that microplastics could remain in the body even after drinking the tea.

The study author Alba Garcia-Rodriguez, a researcher in the Department of Genetics and Microbiology at the Universitat Autonoma de Barcelona said the research calls attention to the path of substantial exposure to plastic particles which are also found in everyday lives. "We have to be concerned about the huge number of single-use plastic that humans are exposed to daily," she said.

How was the test conducted?

Similar tests have been conducted previously. In 2019, a Canadian study was the first one to test nylon and polyethylene tea bags which released 11.6 billion microplastics and 3.1 nanoplastics, measuring less than a micron into a single cup of tea.

In another study from 2023, conducted by Garcia-Redriguez and colleagues, one brand of tea bags were tested that was made of polylactic acid, a biodegradable plant-based plastic. The study showed that it released 1 million nanoplastic particles per tea bag.

For this 2024 study, the research team set broadened their scope by testing out for various materials. They obtained empty tea bags made from three commonly used materials: polypropylene, nylon, and cellulose.

The team simulated typical tea-brewing conditions (without tea leaves) by steeping the bags in sterile water heated to 95°C (203°F) while stirring continuously. They then measured how many plastic particles each material released.

The results revealed that polypropylene bags shed the highest amount of microplastics—approximately 1.2 billion particles. Cellulose paper bags came next, releasing 135 million particles per milliliter, while nylon mesh bags released 8.18 million particles.

The study revealed that hot temperature water exposure and also the stirring of spoon can cause tea bags to "leach plastics".

When the plastics were exposed to humans, it showed that cells absorbed the microplastics, including the mucus cells, as they had the highest uptake of particles. After 24 hours, the particles reached the nucleus of the cells, which houses the DNA.

Health Impacts

Experts find the results concerning, as ingested microplastics could enter the bloodstream after targeting tissues in the gastrointestinal tract, potentially spreading to other organs. While chemicals added during plastic production have been linked to issues like endocrine disruption and cancer, the health effects of ingested microplastics remain unclear. Scientists caution against drawing conclusions, noting that human studies on microplastics are still limited and much more research is needed.

How can one reduce the exposure to plastics? The best way possible is by buying loose leaf, even when you are using green tea, which, is mostly used in tea bags, as a way to make it instantly. In case you are in rush, you can always use the steel infuser to use it as a replacement of plastic tea bags for an instant cup of tea.