Your everyday takeaway coffee may be carrying more than caffeine. New scientific research has found that hot beverages served in plastic or plastic-lined cups can release large numbers of microplastic particles directly into drinks, raising fresh concerns about daily exposure.

What the research found

A recent study published in the Journal of Hazardous Materials: Plastics examined how disposable coffee cups behave when exposed to heat. Researchers analysed data from 30 peer-reviewed studies and conducted real-world testing on 400 takeaway cups collected in Australia.

The findings were clear: temperature plays a critical role. As liquid temperature increases, so does the release of microplastics. Some studies recorded anywhere from a few hundred to more than 80 lakh microplastic particles per litre, depending on the cup material and testing conditions.

Plastic cups release more particles

The study compared fully plastic cups made of polyethylene with paper cups that have a thin plastic lining. Both released microplastics, but all-plastic cups shed significantly more particles, especially when filled with hot liquids.

When water temperature rose from 5°C to 60°C, microplastic release from plastic cups increased by about 33 per cent. Researchers estimate that someone drinking 300 ml of coffee daily from a plastic cup could ingest more than 3.6 lakh microplastic particles every year.

Why heat makes it worse

Microscopic imaging revealed that plastic cups have rough inner surfaces filled with tiny ridges. Heat softens plastic, causing it to expand and contract, which allows more fragments to break away into the drink. Time mattered less than temperature, meaning the initial heat shock is the main trigger.

How consumers can reduce risk

Experts say there is no need to panic, but awareness matters. Using reusable cups made of stainless steel, ceramic or glass is the safest option. If disposable cups are unavoidable, plastic-lined paper cups may be a slightly better choice than fully plastic ones.

Avoiding boiling-hot liquids in plastic containers can also reduce exposure. Small changes in daily habits, researchers say, can significantly lower long-term risks.