Due to the continuous consumption of takeout, coffee, bottled beverages, cooking with non-stick pans, and microwaving food in plastic plates, microplastics are naturally ingested into the human body. Microplastics are challenging for the human body to metabolize and absorb, and the portions that are not eliminated accumulate within the body. In recent years, scientists have identified the presence of microplastics in various organs, such as the digestive system, lungs, and even in the placenta.

Recently, researchers from Capital Medical University in China have astonishingly discovered the presence of microplastics in organs that have had no direct contact with the external environment—the heart and its surrounding tissues!

The researchers detected microplastic particles with diameters ranging from 20 to 469μm in five different types of tissues collected from the heart, including the pericardium, epicardial adipose tissue (EAT), pericardial adipose tissue (PAT), myocardium, and left atrial appendage (LAA).

In order to obtain "direct evidence" of the presence of microplastics in human organs, the researchers recruited 15 participants undergoing heart surgery. Ultimately, they collected 6 pericardial samples, 6 epicardial adipose tissue samples, 11 pericardial adipose tissue samples, 3 myocardial samples, and 5 left atrial appendage samples.

In the end, the presence of microplastics was detected in all five types of samples, with diameters ranging from 20 to 469μm.

Among these, the most common type of microplastic was polyethylene terephthalate (PET), accounting for approximately 77% of the total. PET was highly prevalent in the pericardium, epicardial adipose tissue , pericardial adipose tissue, and myocardium, constituting 96%, 83%, 49%, and 43%, respectively. The second most common type was polyurethane (PU), making up 12% and primarily found in the LAA samples.

It is noteworthy that even though polyethylene (PE) constituted only 1% of the total microplastic particles, it was detected in all tissue samples. Additionally, PE was found in the myocardial sample of patient number 9, indicating that microplastic contamination has reached the deepest anatomical structures within the human body!

Due to the fact that the samples were collected from patients undergoing heart surgery, researchers also identified another source of microplastics—the heart surgery procedure itself.

During the surgical procedure, patients come into contact with various medical instruments that contain plastic components. This exposure leads to changes in the types and diameter distribution of microplastics in the blood samples before and after surgery. For example, the most common type of microplastic detected in the blood before surgery was PET, constituting 67%. In contrast, polyamide (PA) became the predominant type of microplastic particles in the blood samples after surgery.

Therefore, the researchers emphasize that invasive medical procedures are likely to be a overlooked pathway for exposure to microplastics and warrant attention!

Based on the types of food consumed and the quantity of microplastics in different types of food, it is estimated that each person ingests around 50,000 microplastic particles per year. If airborne microplastics, inhaled through breathing, are taken into account, the annual intake of microplastic particles per person ranges from 74,000 to 121,000.

In terms of weight, individuals ingest approximately 5 grams of microplastics per week, equivalent to the weight of a credit card! It's indeed a sobering thought that we might be 'eating' microplastics throughout our lives, potentially posing long-term health implications.