Although scientists have already found microplastics in parts of the body exposed to the environment, such as the lungs, a new pilot study discovered that these plastic fragments can also enter heart tissue.
Plastic is virtually everywhere in the environment. Since its invention, manufacturers have utilized the material to make products that most people use on a daily basis. And according to the United Nations Environment Programme, this includes cosmetics and personal care products such as shower gel, lipstick, and moisturizers.
What's more, reports suggest that exposure to plastic may harm health and contribute to a wide range of health conditions.
As plastic degrades, it becomes microscopic bits called microplastics. These particles are less than 5 millimeters wide and can enter the body through the mouth, nose, and lungs. Moreover, recent research found that inhaled microplastics can collect in the respiratory system, which could pose a health risk.
Still, the mouth, nose, and lungs are directly exposed to any microplastics floating in the air, so it's not surprising that researchers found these particles in the respiratory system. Yet scientists aren't sure if microscopic bits of plastic could migrate into internal organs not exposed to the environment, such as the heart.
However, a new study published in Environmental Science & Technology suggests that, yes, microplastics can get into the heart, and surgical procedures may play a role.
A pilot study gets to the heart of the matter
To investigate whether microplastics can enter the cardiovascular system, researchers from China examined various heart tissue samples taken from 15 people during cardiac surgery. The scientists also took blood samples from half of the individuals before and after the surgical procedures.
Then, the team used a laser direct infrared chemical imaging system and scanning electron microscopy to examine the samples.
In the participants' heart tissue, the researchers found 20 to 500 microplastic particles made from plastic used to manufacture everyday household items, personal care products, and medical devices.
Although not all the heart tissue samples contained microplastics, the scientists identified nine types of plastics in five different heart tissues.
They also detected these same microplastic types in the participants' pre and post-operative bloodwork. However, the distribution of microplastics changed after surgery.
This had the scientists wondering if the surgical procedure itself could introduce microplastics into the heart tissue. After examining this further, they discovered one type of microplastic in three different heart tissues not vulnerable to accidental exposure to plastic during surgery.
"Moreover, the presence of poly(methyl methacrylate) in the left atrial appendage, epicardial adipose tissue, and pericardial adipose tissue cannot be attributed to accidental exposure during surgery, providing direct evidence of microplastics in patients undergoing cardiac surgery," the study authors wrote.
Although the study looked at heart tissue and blood samples from a small number of people, the researchers say their findings show the invasive and persistent nature of microplastics.
The results also pose new questions about invasive medical procedures. Specifically, whether surgeries can introduce microplastics into the bloodstream and internal organs and if microplastic exposure can impact the cardiovascular system or heart surgery outcomes.
The study authors say more research is needed to examine this and other potential effects of microplastics on internal organs and overall health.
- United Nations Environment Programme. Plastic in Cosmetics.
- National Oceanic Service. What are microplastics?
- Environmental Science & Technology. Detection of Various Microplastics in Patients Undergoing Cardiac Surgery.