There's nothing quite like a cup of tea with a side of biscuits - but how about a side of plastic particles?

New research suggests that millions of microscopic plastic particles are released from tea bags, meaning that afternoon brew is likely contaminated by chemicals.

While it's easy to assume that tea bags are made from pure paper, an estimated 96 percent of the bags contain polypropylene - a thermoplastic polymer. This chemical acts as a seal on the tea bags, ensuring they maintain their shape.

Although a number of brands, particularly in the tea-loving UK, have made an effort to remove polypropylene from their products, a high quantity of tea brands worldwide may still contain plastic.



As reported in the Environmental Science & Technology journal, McGill University researchers have investigated whether plastic tea bags could be releasing micro and nano plastics during brewing. It is currently unknown if these particles are harmful to humans.

The plastic tea bags used in the experiment were emptied and washed before being heated, to imitate brewing conditions.