Study Links Microplastics in Blood to Potential Health Risks

A study recently published in Environmental International examined the makeup of microplastics in human blood. Researchers examined the whole blood of 20 healthy participants. 

Eighteen of them had blood that contained 24 polymer types. Most of the microplastics were white and clear fragments. This study supports how microplastics travel all over the body and how they might contribute to particular problems like vascular inflammation or changes in blood clotting function. 

As noted in this study, microplastics (MPs) are defined as synthetic plastic particles that typically range between 1 µm [micrometer] and 5 mm [millimeters] in diameter. Previous findings have identified microplastics in the blood and even in clogged arteries, suggesting potential dangers from microplastics to cardiovascular health. This study wants to reveal more information about the makeup of microplastics in blood and having an understanding of the characteristics might help experts conclude how dangerous microplastics actually are. 

The researchers collected blood samples from 20 healthy, drug-free university students. They acknowledged that the process of collecting blood samples can expose the blood to microplastics. So, they compared the samples to procedural blank samples to help get an idea of what blood could be exposed to during the collection and study period. 

Overall, the researchers analyzed a quarter of each procedural blank and blood sample. They then compared the observed microplastics and chemical additives with known polymer and plastic additive chemicals. 

They included particles that had a 70% match or greater with these libraries in their shown results. The team also used an approach called limit of quantification (LOQ) to help adjust for background contamination of samples. After using the LOQ criteria, they found that only eight out of the 20 samples contained microplastics. In all, only five of the microplastics were above the limit of quantification. Thus, results note the presence of a quantifiable amount of microplastics in 40% of participants. 

When looking at the characteristics of microplastics, researchers found that most were fragments with a clear or white appearance. They were also able to identify several additive chemicals and plastic alternatives in the blood samples. Compared to what previous studies had observed, these particle sizes were much larger, which raises certain questions about the potential health impact. 

This research does have some limitations. First, it is hard to account for potential contamination of samples. While the authors of this study did attempt to account for this, there is not yet a standard protocol to account for background contamination in microplastics research. 

The researchers also only estimated the mass of microplastic polymers, and they acknowledge that they may have underestimated mass and other values. They also cannot be entirely sure of particle composition based on the 70% match or greater criteria they used, and they were further limited by incomplete organic material digestion and the use of Anodisc filters, specialized aluminum oxide membranes used for particle removal. 

Reference – Author links open overlay panelSophie V. L. Leonard a, a, b, c, & AbstractMicroplastics (MPs) are an everyday part of life. (2024). Microplastics in human blood: Polymer types, concentrations and characterisation using μFTIR.

Retrieved from https://www.sciencedirect.com/science/article/pii/S0160412024003374