Scientists have found that tea bags contain millions of micro- and nanoplastics (MNPLs) that may be entering your body every time you drink tea.

Research has shown that some plastics are more readily absorbed by cells in the digestive system and may cause DNA damage. Tea bags with an irregular surface may release more microplastic particles.

Tea Bags Leach Plastic Particles

A study published in the November 2024 issue of Chemosphere examined three types of commercial tea bags made from either nylon, polypropylene, or cellulose (a plant-based material).

The researchers simulated typical tea use by immersing and stirring tea bags in water. They found that all three tea bag materials released microparticles during simulated tea preparation, with polypropylene (PP) releasing the most and nylon releasing the least.

Tea is the second-most-consumed beverage globally, and each plastic tea bag steeped at brewing temperature releases about 11.6 billion microplastics and 3.1 billion nanoplastics. For comparison, a 2024 study found that bottled water contained an average of 240,000 particles per liter—most of which were nanoplastics.

Amount of Leaching Varies by Tea Bag Type

Sphere- and scale-shaped surface irregularities in tea bag fibers, likely resulting from the manufacturing process, may cause the bags to break, releasing MNPLs.

Polypropylene tea bags released the highest number of MNPLs, followed by cellulose. Nylon tea bags released fewer particles because of their woven structure, which made them resistant to breakage and leaching.

Polypropylene and cellulose tea bags showed more surface irregularities and imperfections, which likely contributed to higher levels of particle release. Polypropylene is a widely used plastic found in food packaging and reusable containers.

Nylon is commonly used in high-end pyramid tea bags known for their clear, mesh-like appearance. Pyramid tea bags can also be made from PP, which can be heat-sealed. Compared to nylon, PP feels more plastic-like and less flexible. Packaging for nylon tea bags may mention “nylon mesh” or “woven material,” while PP tea bags are often labeled as “silken” or “heat-sealed.”

Most traditionally shaped tea bags—square, classic, or round—are made of cellulose fibers, giving them a paper-like look and feel. These tea bags are often marketed as “biodegradable” or as being made from “plant-based materials.” However, many newer versions include PP to heat-seal the edges, affecting their biodegradability.

Other tea bag components may also contain plastic, Aidan Charron, associate director of Global Earth Day at EarthDay.org, an organization whose stated purpose is to “diversify, educate and activate the environmental movement worldwide,” told The Epoch Times.

“Often the glue used to stick the bags together, [or] the string (if the bag has one) can have plastics in them,” he wrote in an email.

A new study published in the February 2025 issue of Food Chemistry found that MNPLs can also be present in water, tea leaves, and plastic kettles. This means that every aspect of tea drinking may contribute to MNPL intake.

How Plastic Affects Our Cells

For the Chemosphere article, researchers studied how MNPLs interact with gut cells using three types of colon cancer-derived cell lines, which differed in their ability to produce mucus.

Mucus-producing cells tend to absorb more MNPLs than cells that produce little or no mucus.

Previous studies showed similar results. One study conducted in lung cells found that when particles were incubated with mucin (a key component of mucus), the plastics were more readily absorbed.

All three types of MNPLs reached the cells’ nuclei within 24 hours at a dose of 100 micrograms per milliliter. While not confirmed, researchers suggested that this could cause serious DNA damage, disrupt repair processes, and lead to mutations, which could increase the risk of cancer and genetic disorders.

“Studies on MNPLs are still in the early stages, but their potential effects when absorbed by human cells include damage and mutation to genetic material in the cells,” Bryan Quoc Le, food scientist, food industry consultant, and author of “150 Food Science Questions Answered,” who was not involved in the study, told The Epoch Times.

“More obvious effects are seen on epithelial cells, such as those in the digestive system, potentially leading to conditions like irritable bowel disease, and in the respiratory system, possibly triggering or worsening respiratory issues,” he said.

Are Plastics in Food Avoidable?

Plastics are used worldwide for their versatility, availability, and low cost, making their elimination from daily-use items unrealistic for most people.

The challenges manufacturers face in reducing plastic use depend on consumer demand and production costs.

Some tea producers have successfully transitioned away from plastic, driven by consumer demand and readily available alternatives. However, other industries face greater challenges due to limited options or technological constraints.

Le recommends tea drinkers switch to products that use natural materials or explore loose-leaf options. Alternatives to tea bags include using a metal tea ball with loose tea leaves or a French press.

Beyond tea, people can make informed choices by researching plastic-free alternatives for specific products. Consider replacing plastic water bottles with reusable metal ones and choosing glass over plastic containers for food storage and reheating.