Is Your Coffee Cup Giving You Microplastics? The Truth About To-Go Cups

Last updated: May 25, 2026

Your paper coffee cup probably isn't just paper. Most to-go cups have a thin plastic lining so they can hold hot liquid without leaking, and heat is exactly what makes plastic shed more. If you grab a coffee on the way to work every morning, this may be one of the cheapest microplastic habits to fix, and the fix takes about 30 seconds.

Why “paper” cups aren't really paper

Plain paper would turn into a soggy mess holding hot coffee for twenty minutes. Every disposable hot-drink cup needs a moisture-barrier liner to hold liquid in. The two common options are:

• Polyethylene (PE) liner, the dominant US standard. A thin (~25-30 µm) plastic film bonded to the paperboard. Cheap, effective, recyclable in only a handful of specialized facilities.
• PLA (polylactic acid) liner, plant-based bioplastic, marketed as “compostable”. Better end-of-life story, but it's still a polymer that hydrolyzes and sheds at brewing temperature.

The lid is a separate problem. Most takeaway lids are PP (polypropylene, recycling #5) or PS (polystyrene, #6) and sit directly above the steam from a fresh cup. PS in particular leaches styrene into hot beverages.

What the 2022 hot-drink cup study found

Liu et al. (2022, Hazardous Materials Advances) examined plastic-lined paper cups filled with 85°C (185°F) water (the typical serving temperature for coffee or tea) and measured released particles using both light microscopy and electron microscopy.

• Estimated ~1,500 microplastic particles per cup released into the hot drink.
• Particle release scaled with temperature and contact time.
• Multiple polymer types detected in the liquid, matching the cup liner composition.
• Other studies (e.g., Ranjan 2021) have reported similar or higher counts for some cup types.

For context: if you buy two coffees a day in plastic-lined cups, that's an estimated 1.1 million extra microplastic particles per year, from a single daily habit.

Brand-by-brand reality check

When to-go is unavoidable: lower-risk habits

1. Ask for no lid if you'll drink quickly, eliminates the lid-side exposure.
2. Pour into your own travel mug at the café, they'll fill it directly if you ask.
3. Skip the lid stir-stick. Plastic stirrer + hot liquid + acid = bad combo.
4. Drink it within 10-15 minutes. Longer contact = more particles + more lid-side leaching.
5. Don't reuse a single-use cup. A reheated paper-with-plastic-liner cup is the worst option in your kitchen.
6. Avoid PS / foam cups. Some convenience stores and budget cafés still use them.

Best reusable travel mug picks

What about home coffee setups?

The to-go cup is one daily exposure. Home brewing has its own:

• K-cups / pod coffee, plastic capsules in contact with hot water; switch to stainless reusable pods or skip the format.
• Plastic French press, uncommon but exists; glass or stainless preferred.
• Plastic electric kettles, see our electric kettles guide; glass or fully stainless models eliminate the kettle-side exposure.
• Plastic drip baskets / carafes, older machines especially.

Related reading: microplastics in coffee, coffee by brewing method, electric kettles, 30 kitchen swaps, check before you buy.