Study finds microplastics in your tea... and posh brands are the worst culprits

With more than 100 million cuppas drunk every day, tea has long been Britain’s favourite beverage.

But a brew-up may just have become rather less palatable after scientists found an unpleasant hidden ingredient lurking alongside the milk, hot water and tea leaves.

A study has found that a hot cup of tea made with a teabag contains traces of microplastics – tiny particles of plastic invisible to the human eye, whose effect on our health is still being investigated.

They are thought to come from the bags rather than the tea leaves, because the plastic polypropylene is used to seal them and prevent them falling apart when wet.

Researchers believe that when boiling water is poured on the bags they release microscopic particles of these plastics into the drink – and the bad news for tea snobs is that the most expensive brands are the worst culprits because they sometimes coat their teabags with plastics to make them feel ‘silkier’ and luxurious.

The study is the latest to find microplastics in the food chain, including in tap and bottled water. The concern is that they can enter the body and cause harm, although the World Health Organisation says there is no convincing evidence of health effects in humans.

But research has suggested that an accumulation in the body could be linked to hormone issues, weight gain and some cancers.

The University of Birmingham researchers said: ‘Our findings highlight the potential health risk associated with microplastic contamination in tea.

'The most expensive teabag brand showed the highest concentrations, significantly exceeding those in low-priced teabags.

'Continued exposure to microplastics through drinks may contribute to daily intakes, leading to potential adverse implications for health.’

The study is thought to be the first to look at microplastic contamination of different cold and hot drinks from the same country.

Experts tested 31 drinks from UK brands. None was named. Hot tea had the highest average content, with 60 microplastics per litre – 12 to 15 in a cup or a mug.

This was three times as much as soft drinks, according to the study, which was published in the journal Science of the Total Environment.

Tea in paper cups had among the highest levels, possibly because such cups have a plastic polyethylene coating that may degrade in hot water. Preparing tea in a glass cup decreased the risk.

Hot coffee contained an average of 43 microplastics per litre, with more in a paper cup.

Iced tea and coffee contained fewer microplastics. Fruit juices had an average of 30 per litre, energy drinks contained 25 and other soft drinks averaged 17.

But Dr Tim Bond, of the Tea Advisory Panel, which promotes the health benefits of tea, said: ‘The jury is still out on the impact of microplastics. They are everywhere – even in the air we breathe – so they can’t be fully avoided.’