The Hidden Threat of Microplastics: An Autopsy of the Plastic Body

Illustration by Izzy Liu 

By ​Sophia Pires Peixoto Berquo

Plastics are the backbone of modern life. Toys? Roughly 90% of them worldwide are plastic. Plastic utensils? The United States alone discards nearly 100 million every day. And plastic products in general? Since the 1950s, humanity has produced over 8.3 billion metric tons of plastic, most of which still lingers in some form. It is undeniable that plastic is all around us. However, that sentence may be more literal than anyone imagined.

At first glance, the human body seems worlds apart from plastic. Our organs are made of living tissue, not polyethylene. Yet recent scientific discoveries suggest a new reality: plastic is now a part of us. 

​Plastic’s widespread use has long been celebrated as a triumph of innovation. Lightweight, durable, and versatile, it resists corrosion and can be molded into almost any shape. But the very qualities that make plastic so convenient also make it nearly indestructible. Over time, plastic fragments into particles invisible to the naked eye. These microplastics, smaller than five millimeters in length, aren’t just floating through oceans or washed up on beaches. From the blood that carries oxygen to the sugar that sweetens our coffee, microplastics have infiltrated the most intimate corners of human life. They are in the air we breathe. The question is no longer whether they are inside us, but what their presence is doing to us.

Recent studies have shown that microplastics are carried by wind and traverse cities, even reaching mountains. As we step onto a street, sit in a classroom, or lounge in our living room, we are inhaling invisible plastic fibers. If plastic can climb the summits of mountains, it can definitely find its way into our lungs––and, unfortunately, it already has. Emerging research has begun to link microplastic exposure to cardiovascular disease, brain damage, and lung inflammation. As we conduct an autopsy of the plastic body, we uncover the main places where microplastics have been found: 

The LungsFibers shed from clothing drift through air currents and into our lungs with every breath. These microscopic threads are small enough to slip through the alveoli and become lodged deep within lung tissue, triggering inflammation similar to that caused by urban smog. Researchers have associated the presence of microplastics in the lungs with chronic inflammation, fibrosis, and interstitial lung disease. The human respiratory system, once a symbol of vitality, now mirrors a synthetic filter, breathing in fragments of our own creation. 


The BloodUnder the microscope, scientists have found fragments of polyethylene terephthalate (PET) and polystyrene in human bloodstreams. Detected for the first time in 2022, these particles move freely among red blood cells. No barrier seems absolute; with every sip from a plastic bottle, tiny amounts may enter circulation and travel to vital organs. This exposure can lead to potential hemotoxic effects from chemical additives such as phthalates and BPA, alongside systemic inflammation. 

The LiverThe body’s detoxification center is struggling against this unfamiliar toxin. Additives leached from plastics, including phthalates, bisphenols, and flame retardants, interfere with hormonal regulation and metabolism. The liver, designed to process natural waste, cannot break down the synthetic polymers that resist decomposition. Instead, it stores them, layer upon layer. Their accumulation has been linked to fatty liver disease (NAFLD), hepatic inflammation, and endocrine disruption. 

The PlacentaPerhaps the most haunting discovery is that fragments of polypropylene have been found in the placenta—the tissue connecting a mother and child. Microplastics have crossed the threshold of life itself, appearing before a first breath is even taken. The placenta, once a shield of protection, has become a site of intrusion. This contamination may restrict fetal growth and interfere with development. 

The BrainEarly evidence suggests that nanoplastics––particles smaller than a thousandth of a millimeter––can breach the blood-brain barrier. Within the brain tissue, researchers have traced oxidative stress, inflammation, and altered neural signaling. While the long-term impacts on cognition and mood remain uncertain, these changes have been linked to neuroinflammation and an increased risk of neurodegenerative disease. 


The Heart
Microplastics have even reached the heart. Fragments have been detected in arterial plaque, the fatty buildup that constricts arteries and increases the risk of heart disease. Their presence may heighten cardiovascular inflammation and compound the risk of cardiac conditions. 

Conclusion
This autopsy of the plastic body closes with a paradox: no organ is untouched, yet no visible wound exists. Still, every autopsy also leads to a diagnosis, and awareness is the first incision. Engineers are developing filtration systems to capture fibers from washing machines, biologists are studying enzymes capable of digesting PET, and policymakers are crafting circular-economy laws to hold corporations accountable from production to decay. The cure will not come from a single discipline but from a collective re-engineering of the systems that brought us here.


The story of plastic is as much about what we can create as it is about what we cannot escape. With every breath we take, we are reminded that our future depends on confronting even the most invisible pollutants shaping our world.