Tiny, microscopic bits of plastic have been found almost everywhere researchers look – including throughout the human body. Microplastics and their even tinier cousins, nanoplastics, are probably flowing through your blood and building up in your organs like the lungs and liver. Now, a new study is connecting the dots on microplastics’ mysterious correlation with heart attack and stroke risk.
“There are some microplastics in normal, healthy arteries,” Dr. Ross Clark, a University of New Mexico medical researcher who led the study, told Business Insider before he presented his findings at the meeting of the American Heart Association in Baltimore in April this year. “But the amount that’s there when they become diseased – and become diseased with symptoms – is really, really different,” Clark said.
Clark and his team measured microplastics and nanoplastics in the dangerous, fatty plaque that can build up in arteries, block blood flow, and cause strokes or heart attacks.
Compared to the walls of healthy plaque-free arteries, plaque build-up had 16 times more plastic – just in the people who didn’t have symptoms.
In people who had experienced stroke, mini-stroke, or vision loss, the plaque had 51 times more plastic.
“Wow and not good,” Jaime Ross, a neuroscientist at the University of Rhode Island who was not involved in the study but has studied microplastics in mice, said after reading the results. “It’s very shocking to see 51 times higher,” she said, adding that in her research, a signal that’s just three times stronger is “very robust and striking.”
This research has not yet undergone the scrutiny of peer review, but Clark said he plans to submit it for publication in a peer-reviewed scientific journal later this year, after replicating some of their results.
Genetic Activity Looked Different With Plastic
Clark is a vascular surgeon, not a microplastics specialist. However, he got the idea for this study by talking with his colleague Matthew Campen, who recently discovered that human brains contain a spoon’s worth of plastic.
“We realised together that there really wasn’t a lot of data on nanoplastics and microplastics in the vascular system, within blood vessels,” Clark said.
Previous resesarch had found that people with microplastics in their arterial plaque were more likely to have a heart attack or stroke or die.
To investigate why, Clark studied samples from 48 people’s carotid arteries – the pair of superhighways in your neck that channel blood to your brain.
The difference in plastic quantities surprised him, but his team found another concerning trend too. Cells in the plaque with lots of plastic showed different gene activity than those with low plastic.
In the high-plastic environment, one group of immune cells had switched off a gene that’s associated with turning off inflammation. Clark’s team also found genetic differences in a group of stem cells thought to help prevent heart attacks and strokes by reducing inflammation and stabilising plaque.
“Could it be that microplastics are somehow altering their gene expression?” Clark said. He added that there’s “lots more research needed to fully establish that, but at least it gives us a hint as to where to look.”
Ross, who specialises in the genetic mechanisms behind disease, agreed that more research is needed, but added that she thinks “these plastics are doing something with these plaques.”
This article was originally published by Business Insider.
SOURCE: Science Alert
