Do Tea Bags Have Microplastics? A Materials Guide for the Premium Tea Drinker

Yes, some tea bags release microplastics, and the material matters enormously. First-generation pyramid bags made from nylon or PET released billions of nano-particles per cup. That finding drove most of the alarm in this category. Those bags have become uncommon at the premium tier: most pyramid bags from serious tea brands today use PLA, a plant-derived bioplastic from corn starch, that releases far fewer particles in a different polymer class. What follows is a guide to the four primary tea-bag formats, what each one releases into hot water, and which grade of tea each format can physically hold.

This is a materials guide for buyers who want to understand what’s in their tea. It is not a marketing case, and not an alarm bell. The four primary tea-bag formats behave differently in the cup. The headline studies that drive most of the “microplastics in tea” panic tested specific materials that are not what most serious tea brands use today. And the trade-offs between formats affect not just particle release, but also what grade of tea can actually go into the tea bag; a connection most articles miss entirely.

1. The 2019 McGill study, addressed by name

The single piece of research that drives nearly every “billions of microplastics in your tea” headline is Hernandez et al. (2019), published in Environmental Science & Technology by a team at McGill University. The finding was striking. A single plastic tea bag, brewed at 95°C, released approximately 11.6 billion microplastic particles and 3.1 billion nanoplastic particles into the cup.

The detail almost always omitted from the headline: the McGill team tested two materials specifically. Both were petroleum-derived plastics, nylon and PET (polyethylene terephthalate). Neither was PLA, abaca paper, or any of the formats that dominate the premium tea shelf today. The study did not test “tea bags” as a category. It tested two specific commercial bag materials and reported what they released.

A premium tea brand using PLA pyramid sachets is not implicated by the McGill finding. A brand still uses nylon “silken” mesh pyramid bags, but these are now uncommon at the premium tier and confined mostly to legacy product lines and budget “luxury” supermarket brands. Subsequent research has confirmed that PLA bags do release some particles too, but at a fraction of the count, in a different polymer class (compostable bio-based, not petroleum), and with significantly shorter environmental persistence.

2. The four primary tea-bag formats, ranked

A few clarifications worth making.

There are two paper-bag formats, not one. Most articles treat “paper tea bags” as a single thing. They are not. Pillow-style bags require a thermoplastic binder integrated into the paper fibers to enable heat-sealing on production machinery. Double-chamber bags, the classic Lipton-style format closed with an aluminum staple or a knotted string, contain no binder at all. The abaca fiber itself is natural in both formats; the difference is whether the tea bag uses thermoplastic seal.

Nylon mesh pyramid bags are increasingly historical. The first generation of pyramid tea bags used nylon mesh as a filter material. With the increased availability of plant-derived biopolymers, especially PLA and now non-GMO PLA, it is uncommon to find new pyramid tea bags made from nylon at the premium tier today. Pyramid tea bags were, in fact, one of the earliest commercial applications of plant-based bioplastics. The tea category helped advance the cost economics of PLA at a scale that has since enabled its use across food service, packaging, and 3D printing.

PLA fragments before it fully degrades. PLA is industrially compostable and does fully break down. During that process, it will be fragmented into particle-sized pieces. But unlike petroleum plastics, tea-bag-grade PLA is inert, contains no phthalates or plasticizer additives, and breaks down into compounds that re-enter the natural carbon cycle rather than persisting in the environment for centuries. The amount of PLA that might enter the human body during normal consumption is effectively negligible.

Put simply: no tea bag format is currently zero-microplastic, but the differences between them span four orders of magnitude. PLA pyramids are meaningfully better than nylon and PET on every measurable axis. Double-chamber paper is the lowest-plastic format overall. The trade-off between the two becomes meaningful only when you understand what the format dictates about the tea inside.

3. The insight nobody else makes: format dictates leaf quality

Here is a connection almost no other article on this topic mentions, and it changes the buying decision for premium tea specifically.

The bag format determines what grade of tea can physically go inside.

• Pyramid sachets (PLA or otherwise) are weigh-filled. Production machines dose each bag by weight, not by volume. This means the bag can hold whole-leaf tea, large-cut botanicals, and the irregularly shaped grades that premium tea is.
• Both paper formats (pillow and double-chamber) are volumetrically dosed. High-speed lines dose by cubic volume per second. For the bag to fill consistently, the tea inside must flow predictably, which requires it to be finely cut. The industry terms are fannings (small broken leaf pieces) and dust (the smallest grade). These are the lower fractions left after the larger leaves have been sorted out.

The consequence is direct. Paper tea bags, whether pillow-style or double-chamber, physically cannot contain premium whole-leaf tea. The format is mechanically optimized for throughput, not for showcasing leaf integrity. And finely cut tea has another downside: more exposed cell structure and surface area accelerates oxidation, which reduces shelf life. Whole-leaf teas retain their integrity, their aromatic compounds, and their quality longer.

This is why nearly every premium tea brand that takes leaf quality seriously uses pyramid sachets. At the premium tier, the microplastic conversation is not “pyramid versus paper.” It’s “PLA pyramid versus everything else,” because paper isn’t an option for the leaf grade that justifies the price.

4. System context: where microplastics actually come from

For perspective on the magnitude of teabag microplastic concern, the largest primary sources of microplastics globally (per OECD’s 2022 Global Plastics Outlook and Napper & Thompson, 2016):

The everyday exposures most consumers don’t think about are orders of magnitude higher than tea bags. Pulling a fleece jacket out of the dryer releases and aerosolizes a meaningful amount of petroleum-based microplastic fiber into the air around you, and that exposure compounds the moment you step into a car, where tire-wear particles concentrate. A useful exercise on the next grocery run: look at how much of the packaging in the cart is plastic. Bread bags, yogurt containers, cheese wrappers, frozen vegetable bags, condiment bottles, and snack bags. By the time the cart is loaded, the household is carrying more plastic mass than a year of daily PLA-bag tea drinking. None of this excuses anything. It calibrates the magnitude.

In that broader context, tea bags are a negligible vector overall. Once the primary sources of daily microplastic exposure are accounted for, the meaningful distinction lies in material choice within the tea bag category.

5. Why Saint Graal chose PLA

We use non-GMO PLA pyramid sachets in our Six-Origin Box. The reasoning:

• PLA is meaningfully better than nylon or PET on every measurable axis. Bio-based feedstock, lower carbon footprint, lower particle release in hot water, and far shorter environmental persistence.
• PLA is the only format that lets us serve whole-leaf and large-cut tea. Switching to either paper format would require switching to fannings, a tea-quality compromise we won’t make.
• Tea bag-grade PLA is inert and contains no phthalates or plasticizer additives. It is FDA-approved for food contact. The amount that might enter the body during normal consumption is effectively negligible. Personally, I would have no reservation eating PLA tea bag every day.
• PLA is honest about its tradeoffs. It is not zero-microplastic. It is industrially compostable, not backyard-compostable. It has a higher agricultural water footprint than petroleum plastics but a 75% reduction in carbon footprint. We don’t claim otherwise on our packaging or anywhere else.
• For the buyer minimizing exposure across their whole life, loose-leaf tea brewed in a steel or ceramic infuser remains the absolute lowest-particle option; just don’t use a plastic kettle to boil your water. Our pyramid sachets are a portability format. The leaf inside them is the same grade we’d sell loose.

One historical note worth making: pyramid tea bags were one of the earliest commercial applications of plant-based bioplastics. The tea category helped advance the cost economics of PLA at a scale that has since enabled its use across other industries, including 3D printing. Tea was an early mover here, well before broader awareness of microplastics made the choice mainstream.

6. How to tell if your tea bag contains plastic

A practical guide buyers can apply at home, to any tea brand:

• Shiny, silky, transparent mesh. Nylon or PET. Now uncommon, but if you see it, it’s petroleum plastic and the highest-shedding format.
• Pyramid shape, not silky-feeling. Almost certainly PLA today. If the brand doesn’t disclose, ask.
• Flat paper “pillow” bag (no staple or string). Mostly abaca paper, but contains a thermoplastic binder fiber for heat-sealing.
• Double-chamber paper bag with a staple or string closure. Pure paper, no binder. The lowest-plastic bag format available.
• Loose leaf brewed in a steel, ceramic, or glass infuser. The only fully plastic-free option.

Packaging that explicitly says “plastic-free tea bags” is a useful signal, but check what the brand defines as plastic-free. Many pillow-style bags carry the label while still containing thermoplastic binders in the paper fiber.

FAQ

Do tea bags have microplastics? Most do, but the amount and material vary dramatically. Nylon and PET mesh “silken” pyramid bags release the highest particle counts (billions per cup per Hernandez et al., 2019), though these are now uncommon at the premium tier. PLA pyramid bags, made from plant-derived bioplastic, release far fewer particles in a different polymer class. Pillow-style paper bags contain a small amount of thermoplastic binder at the fiber level. Double-chamber paper bags (the classic staple-or-string format) contain no plastic. Loose leaf brewed in a steel infuser releases none.

Are tea bags plastic? Some are entirely plastic (nylon, PET mesh, now uncommon). Some are mostly natural with a small plastic binder (pillow-style paper bags). Some are pure paper with no plastic (double-chamber paper bags sealed with a staple or string). Some are bio-based plastic, not petroleum (PLA pyramids). The packaging often doesn’t disclose which. A brand’s transparency about materials is the strongest signal of what’s actually in the bag.

Are PLA tea bags safe? PLA (polylactic acid) is bio-based, derived from corn starch or sugarcane, and FDA-approved for food contact. Tea-bag-grade PLA is inert and contains no phthalates or plasticizer additives. It releases substantially fewer particles than nylon or PET in hot water but is not zero-microplastic. The polymer class is different (bioplastic, designed to break down into compounds that re-enter the carbon cycle), and the amount that might enter the human body during normal consumption is effectively negligible.

What’s the difference between pillow-style and double-chamber paper tea bags? Pillow-style paper bags use a thermoplastic binder integrated into the abaca fiber to enable heat-sealing on production machinery. Double-chamber paper bags use no binder; they’re closed with an aluminum staple or a knotted string instead. Both are typically made from abaca (banana-plant fiber). For minimizing microplastic exposure specifically, double-chamber is the cleaner option. Both formats require finely cut tea due to volumetric filling.

What’s the safest type of tea bag for minimizing microplastics? Strictly ranked: (1) loose leaf in a steel, ceramic, or glass infuser; (2) double-chamber paper bags sealed with an aluminum staple or string (no binder); (3) PLA pyramid bags; (4) pillow-style paper bags with thermoplastic binder; (5) nylon or PET mesh pyramids. For premium whole-leaf tea, only options 1 and 3 are compatible with the leaf grades that justify the price.

Why doesn’t every premium tea brand just use paper bags? Because both paper formats require finely cut tea (fannings or dust) to flow through volumetric-fill machinery. Premium tea is sold by leaf integrity: whole leaves, retained essential oils, recognizable shapes. A paper bag can’t physically hold that grade and still seal correctly. Pyramid sachets are weigh-filled, which is the only format that accommodates whole leaf. The finely cut tea required for paper formats also has more exposed surface area, which accelerates oxidation and shortens shelf life.

What about the 2019 McGill study that found billions of microplastics in tea bags? The McGill study (Hernandez et al., 2019, Environmental Science & Technology) tested two specific materials: nylon and PET. The billion-particle finding applies to those materials in hot water. It does not extend to PLA, abaca, or paper-based bags, which were not tested. Subsequent research on PLA has shown materially lower particle release.

Is loose-leaf tea always safer than tea bags? For microplastic exposure specifically, yes, assuming you brew with a non-plastic infuser. Steel mesh balls, ceramic teapots with built-in strainers, and unglazed clay teaware all release zero microplastics. But loose-leaf requires more brewing setup. Pyramid sachets are a portability format that lets you carry premium tea to a hotel room, an office, or a friend’s kitchen.

Are “plastic-free” paper tea bags actually plastic-free? It depends on the paper format. Double-chamber paper bags sealed with an aluminum staple or knotted string genuinely contain no plastic. Pillow-style paper bags use a thermoplastic binder integrated into the fiber to enable heat-sealing; these are mostly natural, but not truly plastic-free. Brands that label pillow-style bags as “plastic-free” are sometimes overclaimed. The abaca fiber itself is natural in both formats.

Sources

• Hernandez, L. M., et al. (2019). “Plastic Teabags Release Billions of Microparticles and Nanoparticles into Tea.” Environmental Science & Technology, 53(21), 12300–12310.
• Napper, I. E., & Thompson, R. C. (2016). “Release of synthetic microplastic plastic fibres from domestic washing machines: Effects of fabric type and washing conditions.” Marine Pollution Bulletin, 112(1–2), 39–45.
• OECD (2022). Global Plastics Outlook: Policy Scenarios to 2060.
• Le, T. M. D., et al. (2023). “Behavior, Characteristics and Sources of Microplastics in Tea.” MDPI Horticulturae, 9(2), 174.

Saint Graal’s Six-Origin Box ships six single-origin teas in PLA pyramid sachets, nested in a lacquered presentation box.