Microplastics in the body could one day show up on MRI scans

Tiny fragments of plastic are everywhere: in the sea, in our food and, as scientists have discovered in recent years, inside us. Microplastics have been found in human blood, the placenta, the liver, the kidneys and even the brain. What they do there is still largely a mystery. Researchers at Maastricht UMC+ think a familiar hospital machine could help solve it.

In a study published this month in the European Journal of Radiology, the team shows that clumps of micro- and nanoplastics can be made visible on a magnetic resonance imaging (MRI) scan. It is a laboratory result, not yet a test for patients, but the researchers see it as an important first step.

Why seeing them matters

Until now, the only way to measure microplastics in human tissue has been to remove that tissue and analyse it in a lab, usually after death. That makes it almost impossible to follow what happens to the particles in living people: where they collect, whether they stay, and whether they are linked to illness.

"The potential impact of plastics on human health remains unclear," the authors write, "in part due to the difficulty of observing them" in living bodies. A scan that could show plastic without cutting anything out would change that.

How the study worked

Rather than using neatly manufactured test particles, the scientists worked with real plastic pollution: microplastics extracted from ocean water. They mixed these particles into a gel designed to respond like human tissue inside a scanner, and then scanned the gel using several MRI settings.

On the standard scans that radiologists look at every day, the plastic could not be seen. But a more specialised technique called susceptibility weighted imaging (SWI) told a different story. SWI picks up tiny disturbances in the scanner's magnetic field and is already used in hospitals, for example to spot very small bleeds in the brain. On these scans, accumulations of plastic particles showed up.

"We see this as an important first step towards making microplastics visible in living organisms. If we can actually track these particles in humans in the future, a unique opportunity will arise to investigate whether and how accumulations of microplastics are associated with organ damage or disease," said first author Maxime Imperatori. 

Not ready for patients yet

The researchers are clear that this is the start of the road, not the end. The particles were scanned in a gel, not in a person or an animal, and much more research is needed before the technique can be used in practice. Scientists will need to learn, for instance, how much plastic has to gather in one place before it becomes visible, and whether the signal can be reliably told apart from other material in the body.

What it could mean

If the approach does work in living people, it could open up a whole new line of research. Doctors and scientists would be able to see where microplastics build up and follow that over time, and then study whether those build-ups are linked to organ damage or disease.

That, the team says, could help answer one of the big questions of our plastic age: what all this invisible pollution is actually doing to our health.