Popular tea bags made from polymer fibres release huge quantities of toxic micro- and nanoplastics into the liquid while they’re brewing, according to a new study.
Researchers brewed tea using popular tea bags made from the polymers nylon-6, polypropylene and cellulose and measured levels of plastic particles in the tea.
Polypropylene was showed to release approximately 1.2 billion plastic particles per milliliter of liquid. Cellulose released about 135 million particles per milliliter and nylon-6 8.8 million particles per milliliter.
The researchers then tested the collected plastic particles to see how they interacted with cells in the human digestive system. They showed that mucus-producing intestinal cells had the highest uptake of micro- and nanoplastics. Particles were even able to enter the cell nucleus, which stores the cell’s genetic material.
Microplastics have been linked to more or less all of the prevailing chronic diseases of modernity, from respiratory diseases to digestive conditions like IBS, heart disease and even neurological and behavioral conditions like autism.
More than nine billion tons of plastic are estimated to have been produced between 1950 and 2017, with over half of that total having been produced since 2004. The vast majority of plastic ends up in the environment in one form or another, where it breaks down, through weathering, exposure to UV light and organisms of all kinds, into smaller and smaller pieces—microplastics and then nanoplastics. These are “secondary” microplastics, because they start off big and end up small. “Primary” microplastics are small by design, like so-called “microbeads” used in cosmetics.
Within our homes, microplastics are mainly produced when synthetic fibres from clothes, furnishings and carpets are shed. They accumulate in large quantities in dust and float around in the air, which we then inhale.
If you want to learn more about microplastics, the potential health consequences of exposure, and what you can do to protect yourself and your loved ones, read our detailed primer, “The Microplastic Menace.”