A SOOTHING cup of tea might not be doing wonders for your health, scientists warn.
Sipping on your staple brew could release billions of microplastics into your body, research from the Universitat Autònoma de Barcelona suggests.
The culprit? Teabags.
According to the researchers, the tea leaf-filled pouches are steeped in microplastics, which are released into our bodies as we drink.
How these tiny fragments of plastic may affect our health is not yet clear.
But previous research has identified them in penile tissue and human breast milk.
Other studies have shown that food packaging – such as plastic bottles, cups and Tupperware – is a major source of microplastics.
“The potential health implications of environmental micro/nanoplastics (MNPLs) are increasingly concerning,” the Spanish researchers said.
“Beyond environmental exposure, other sources such as food packaging, including herbal teabags, may also be significant.”
The team tested three popular teabags – easily purchased online or in supermarkets – to try and gage how many microplastics we may be ingesting from each after brewing a cup in the “standard” way.
The study – published in the journal Chemosphere – found that most of these microplastics are sucked up by mucus-producing intestinal cells.
But researchers found that some can even enter the cell nucleus, which is the part of the cell that houses genetic material, MailOnline reported.
The first teabag tested was one made of nylon, which researchers ordered from Amazon.
The second was a polypropylene teabag ordered from AliExpress and the third was bought from a supermarket and had an unknown filter polymer.
While the teabags ordered online came empty, those containing tea were emptied and rinsed with water.
Researchers then steeped 300 of each teabag type in 600ml of water heated to 95°C.
All three teabags released huge amounts of tiny plastic particles into the water, the team observed.
The polypropylene teabags were the worst offenders, releasing approximately 1.2billion particles per millilitre, with an average size of 136.7 nanometres.
Nylon teabags released 8.18million particles per millilitre, with an average size of 13.8.4 nanometres.
Next, the researchers stained the microplastics before exposing them to different types of human intestinal cells.
Mucus-producing intestinal cells seemed to suck up most of the microplastics and some particles were even able to enter the cell nucleus.
Microplastics are tiny plastic particles less than five millimetres in diameter.
They come from a variety of sources in our everyday life, from larger pieces of plastic debris, such as from the degradation of bottles, to the tiny beads in personal care products like toothpaste and exfoliants, and synthetic fibres from textiles like polyester and nylon.
We can either ingest them, for example in food and water contaminated with them, or inhale them from the air.
There is growing concern about the potential health impacts of microplastics on both the environment and human health.
When ingested or inhaled, microplastics can cause physical and chemical damage to living organisms.
Studies have shown that they may be involved in inflammation in the body by leading to the release of proteins called inflammatory cytokines.
While these studies are typically small and in animals or cells, inflammation is linked to a range of chronic diseases, including heart disease, autoimmune disorders, and cancer.
Cellular damage has been a key focus of studies on microplastics.
The tiny pieces of plastic have been shown to cause cell death, cause damage via oxidative stress, and interfere with hormone function.
There is also evidence to suggest that microplastics can cause genotoxic effects, meaning they can damage genetic material within cells – raising fears they can contribute to cancer.
The evidence is still evolving for these tiny particles that are barely visible to the naked eye.
The study team said their results highlight the need for further research on how chronic microplastic exposure can affect human health.
“It is critical to develop standardised test methods to assess micro/nanoplastics (MNPLs) contamination released from plastic food contact materials and to formulate regulatory policies to effectively mitigate and minimise this contamination,” researchers said.
“As the use of plastic in food packaging continues to increase, it is vital to address MNPLs contamination to ensure food safety and protect public health.
“Overall, our findings contribute to a growing body of evidence on the pervasive nature of plastic pollution and its potential implications for human health.”
It comes after a review of 3,000 studies found that microplastics could be to blame for respiratory issues and additional health problems, like cancer and infertility.
Experts also revealed that the microparticles could also be a trigger for chronic pulmonary inflammation, which can heighten lung cancer risk.
Previous research has suggested that cancer cells in the gut spread at an accelerated rate after contact with microplastics.
