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.