Microplastics found in blood clots in the heart, brain and legs: ScienceAlert

Earlier this year, we received news of a landmark study that found microplastics – tiny shards of plastic from larger pieces – were found in more than 50% of fatty deposits from clogged arteries. This is the first data of its kind linking microplastics and their impact on human health.

Now, a new study by Chinese researchers reports the discovery of microplastics in blood clots surgically removed from arteries in the heart and brain, as well as deep veins in the lower legs.

This is only a small study of 30 patients – a far cry from the 257 patients followed for 34 months in the arterial plaque study published in March.

But in the same way that the Italian-led team found that the presence of microplastics in plaques increased the subsequent risk of heart attack or stroke, the Chinese team also discovered a potential association between levels of microplastics in blood clots and disease severity.

All 30 patients involved in the study underwent surgery to remove blood clots after suffering a stroke, heart attack or deep vein thrombosis, a condition in which clots form in deep veins, usually legs or pelvis.

Aged an average of 65 years, the patients had varied health histories and lifestyles such as smoking, alcohol consumption, high blood pressure or diabetes. They used plastic products daily and were roughly divided between rural and urban areas.

Microplastics of different shapes and sizes were detected using chemical analysis techniques in 24 of the 30 blood clots studied, at different concentrations.

The tests also identified the same types of plastics as those detected in the Italian arterial plaque study: polyvinyl chloride (PVC) and polyethylene (PE). This is not surprising since PVC (often used in construction) and PE (primarily used in bottles and shopping bags) are two of the most commonly produced plastics.

The new study also detected polyamide 66 in the clots, a plastic commonly used in fabrics and textiles. Of the 15 types identified in the study, PE was the most common plastic, accounting for 54% of the particles analyzed.

The researchers also found that people with higher levels of microplastics in their blood clots also had higher levels of D-dimer than patients without microplastics detected in the thrombi.

D-dimer is a protein fragment released when blood clots break down; it is not normally present in blood plasma. High levels of D-dimer in a blood test can indicate the presence of blood clots, leading researchers to suspect that microplastics might build up in the blood to worsen clotting.

But more research is needed to investigate this; This study did not measure microplastics in patients’ blood and being an observational study, it can only point to possible links, not causes.

“These results suggest that microplastics may be a potential risk factor associated with vascular health,” write Tingting Wang, a clinician-scientist at the First Affiliated Hospital of Shantou University Medical College in China, and colleagues in their article.

“Future research with a larger sample size is urgently needed to identify sources of exposure and validate the trends observed in the study.”

With microplastics already detected in human lung tissue and blood samples, it’s easy to imagine how these microscopic pieces of plastic make their way from the environment into our bodies, and blood clots if they form – although scientists cannot trace this step. gradually.

A 2023 study previously detected the chemical “fingerprints” of microplastics in 16 surgically removed blood clots. Thanks to the work of Wang and his team, which used infrared chemical imaging and other methods, we now have an idea of ​​the concentration of these plastic particles in blood clots and their possible health effects.

This shows how quickly this field is evolving, from detecting microplastics in human tissues, to studying their effects on cells and mice, to elucidating the impacts of microplastics on human health.

The results couldn’t come fast enough. Plastic production is only increasing, with fossil fuel companies increasing production while their other business prospects collapse.

“Due to the ubiquity of microplastics in the environment and in everyday products, human exposure to PM is inevitable,” Wang and colleagues warn.

“As such, there is growing concern about microplastic pollutants due to their widespread presence and potential health implications.”

The study was published in eBioMedicine.