Correction (18/08): The headline and content of this article has been updated to clarify that researchers exposed microplastics to the human tissues before studying them.
Previous studies in wildlife has linked micro- and nanoplastic exposure to infertility, inflammation and cancer, but health outcomes in humans are currently unknown. Now, a new study from researchers from Arizona State University has found evidence that human organs and tissue can absorb traces of nano and microplastics.
The team tested 47 samples taken from lungs, liver, spleen and kidneys – four organs likely to be exposed to, filter or collect microplastics – from a pre-existing repository of brain and body tissues that was established to study neurodegenerative diseases, such as Alzheimer’s.
After exposing the tissue samples to a range of microplastics and then putting them through a mass spectrometer they found that every sample contained traces of plastic including polycarbonate (PC), polyethylene terephthalate (PET) and polyethylene (PE). Bisphenol A (BPA), a substance still used in many food containers despite health concerns, was found in all 47 human samples.
“You can find plastics contaminating the environment at virtually every location on the globe, and in a few short decades, we’ve gone from seeing plastic as a wonderful benefit to considering it a threat,” said co-author and PhD student Charles Rolsky.
“There’s evidence that plastic is making its way into our bodies, but very few studies have looked for it there. And at this point, we don’t know whether this plastic is just a nuisance or whether it represents a human health hazard.”
The researchers also created a computer program that converted information on plastic particle count into units of mass and surface area that they plan to share online so that other researchers can report their results in a standardised manner.
They now plan to investigate any potential health risks that may arise due to plastic contamination.
“We never want to be alarmist, but it is concerning that these non-biodegradable materials that are present everywhere can enter and accumulate in human tissues, and we don’t know the possible health effects,” said PhD student and co-author Varun Kelkar.
“Once we get a better idea of what’s in the tissues, we can conduct epidemiological studies to assess human health outcomes. That way, we can start to understand the potential health risks, if any.”
Reader Q&A: How does plastic get into the oceans?
Asked by: Tamsin Nicholson, via email
Around 80 per cent of the plastic waste found in the oceans today originated inland. Littering, poor waste management and industrial activity can all allow plastic to enter the natural environment.
A significant proportion of this then blows into rivers and streams, which carry it into the ocean. This is particularly common in countries where waste infrastructure is lacking: an estimated two billion people worldwide don’t have access to solid waste collection.
On top of this, wastewater from our homes often contains tiny pieces of plastic, including microbeads from cosmetics (now banned in the UK) and fibres from polyester clothing. Tackling plastic pollution therefore requires individuals, governments and companies across the globe to work together to reduce plastic consumption and waste.