End Plastics
Real Life Operation: How Plastics Live in Your Body
February 14, 2025
Microplastics are small plastic particles, no bigger than a grain of rice, that shed off everything made of plastics; from plastic packaging to plastic bags to plastic kitchenware clothes made of polyester which is a plastic textile. Plastic is made from oil with toxic chemicals used to give it the specific qualities plastic products need.
Once these microplastics shed they get into our water supply, our oceans, our homes, our air, and even into the food chain itself. New research is increasingly finding associations between ingesting and inhaling these microplastics and the toxic chemicals that leach from them with a variety of serious health issues. Ranging from respiratory and cardiovascular problems to neurodegenerative diseases like Alzheimer’s.
What researchers are discovering is that microplastics and their additive chemicals potentially impact human health in a variety of ways. Similar to the game, Operation, your organs are almost as full of plastics as the game. So, here’s a rundown of some of the most compelling research to date on how specific parts of our body are impacted.
The Brains of Mice and Men
Research, just published in the journal Nature Medicine, analyzed samples of some of the major organs, including the brain, from 28 people who died in 2016 and then compared them to the brains (and major organs) of people 24 who died just 8 years later in 2024. What they found was that the concentration of microplastic in the brain tissue was higher and had increased since 2016.
The microplastics discovered were nano shards of plastic – 75% of which were made of polyethylene, which is most commonly used to make plastic bags and food packaging.
Another study in September 2024, studied the brains of 15 deceased individuals. Scientists examined the olfactory bulbs of human brains which were analyzed through micro-Fourier transform infrared spectroscopy. Microplastics were found in the olfactory bulbs of 8 individuals, primarily in the form of microparticles and fibers. In this research polypropylene was the most frequently identified polymer.
This all backs up earlier research from an August 2023 in a study by the George and Anne Ryan Institute for Neuroscience, University of Rhode Island. This revealed that microplastics could cross the blood brain barrier of mice potentially contributing to neurodegenerative diseases like Alzheimer’s.
Their research indicated that exposure to microplastics led to a decrease in glial fibrillary acidic protein (GFAP), a protein essential for supporting various brain cell processes, like communication. A reduction in GFAP levels has been associated with early stages of neurodegenerative diseases as well as depression.
Microplastic exposure has also been linked to behavioral changes and alterations in immune markers within the brain. These findings suggest that microplastics may lead to cognitive impairments and even behavioral issues.
The Lungs
It’s not just the brain – microplastics have been detected in human lungs too, raising concerns about their impact on respiratory health. Research published in January of 2024 by the University of Technology, Sydney, found that inhaling tiny plastic particles can lead to inflammation, oxidative stress, and impaired lung function.
The ultra-fine size of microplastics allows them to travel deep into the respiratory tract, potentially reaching the alveoli—where the critical process of gas exchange takes place. This opens the door to long-term health risks, including chronic respiratory conditions like asthma and COPD.
Additionally, prolonged exposure has been shown to increase inflammation in lung tissues, attracting inflammatory cells and triggering macrophage aggregation—markers of severe systemic inflammation. This heightened immune response could damage lung tissue over time, making individuals more vulnerable to respiratory illnesses.
Beyond direct lung damage, there’s the looming concern of microplastics translocating to other organs via the bloodstream. This could have systemic consequences, affecting vital systems like the cardiovascular and immune systems. The potential for microplastics to act as vectors for harmful chemicals or pathogens only adds to the alarm.
The Heart
Our brains and lungs are not alone. Microplastics have been found in human hearts too. In a groundbreaking study published in the New England Journal of Medicine, scientists analyzed the carotid plaques of 257 patients who had undergone surgery to remove fatty deposits from their neck arteries. The researchers found microplastics in 58% of the plaques, suggesting that these particles may be embedded within the arterial walls.
Over an average follow-up period of 34 months, participants whose plaques contained microplastics were found to be 4.5 times more likely to experience a heart attack compared to those without microplastic contamination. This discovery raises significant concerns about the potential role of microplastics in the development of atherosclerosis—a condition where fatty deposits accumulate in the arteries, restricting blood flow and increasing the likelihood of severe cardiovascular events.
Moreover, the presence of microplastics in arterial plaques has also been correlated with an elevated risk of stroke, further highlighting their potential role in the pathophysiology of vascular disease. These findings suggest that microplastics may not only contribute to the physical buildup of fatty deposits but may also exacerbate inflammation and oxidative stress within the vascular system, driving the progression of atherosclerosis.
The growing body of evidence implicating microplastics in cardiovascular health underscores the urgent need for further research to determine the mechanisms by which these particles influence arterial plaque formation and to understand the broader implications for public health.
The Gut
Microplastics represent a significant and often overlooked threat to gut health too, impacting the gastrointestinal system through a range of biological mechanisms. Numerous studies have shown that microplastic exposure can alter the gut microbiome, with a growing body of evidence indicating that these tiny particles disrupt the delicate balance of gut bacteria.
A 2021 study published in Environmental International found that microplastic exposure can significantly shift the gut microbiota composition in both animal models and humans, promoting dysbiosis—a state of microbial imbalance between beneficial and harmful bacteria. This shift towards dysbiosis has been implicated in the pathogenesis of several gastrointestinal disorders, including inflammatory bowel diseases (IBD) like Crohn’s disease and ulcerative colitis, as well as metabolic disorders like obesity and diabetes.
Further compounding the risk, microplastics can directly interact with the intestinal lining. Research published in Nature Nanotechnology in 2020 demonstrated that microplastics can physically damage intestinal cells, leading to increased intestinal permeability, commonly referred to as “leaky gut”. This disruption of the gut barrier function allows harmful substances, such as toxins, pathogens, and undigested food particles, to leak into the bloodstream, triggering systemic inflammation and immune responses. These breaches in the gut lining have been linked to a host of health issues, ranging from autoimmune diseases to chronic inflammatory conditions.
Additionally, studies have shown that microplastics themselves can act as vectors for toxic substances, including endocrine-disrupting chemicals and heavy metals, further exacerbating their harmful effects on gut health, and contributing to systemic toxicity. A 2022 study published in Science of the Total Environment found that microplastics can adsorb harmful chemicals from the environment, such as pesticides and industrial pollutants, which are then transferred into the digestive system upon ingestion.
This bioaccumulation can have profound long-term health consequences, including liver and kidney damage, as well as disrupting hormonal balance.
Reproduction
Microplastics are emerging as a significant human health hazard with the potential to disrupt various organs and systems inside the human body including the reproductive system.
The endocrine-disrupting properties of microplastics are of particular concern. These tiny particles have been shown to interfere with the body’s hormonal regulation, leading to a cascade of effects that could contribute to reproductive toxicity. Microplastics, particularly those in the form of nano-sized particles, can mimic or block the action of natural hormones, disrupting the delicate balance necessary for normal reproductive function.
This phenomenon is primarily attributed to the adsorption of endocrine-disrupting chemicals (EDCs) onto the surface of microplastics, such as bisphenol A (BPA), phthalates, and polychlorinated biphenyls (PCBs), which are known to interfere with estrogen, testosterone, and thyroid hormones.
A study by Peng et al. in Environmental Pollution highlighted how microplastics can act as vectors for these EDCs, promoting a range of adverse effects on both male and female reproductive health.
The study found that exposure to microplastics resulted in the disruption of estrogen receptor signaling pathways, a key mechanism involved in regulating ovarian and testicular function. In particular, the study pointed to the potential for microplastics to increase the risk of conditions such as polycystic ovary syndrome (PCOS) in women and decreased testosterone levels in men, both of which are linked to fertility issues. Moreover, the ability of microplastics to cross biological barriers, including the blood-testis and blood-ovary barriers, makes them a particularly insidious threat to reproductive health.
In terms of direct impact on fertility, a study led by Itishree Dubey from the Department of Pharmacology and Toxicology at the National Institute of Pharmaceutical Education and Research further elucidated the effects of microplastics on reproductive function. This study, published in 2021 in Toxicology and Applied Pharmacology, found that microplastic exposure led to compromised sperm motility, decreased sperm count, and lower testosterone levels in male rats (Dubey et al., 2021).
These findings suggest that microplastics might hinder male fertility by directly affecting sperm function and hormone production. Additionally, the study indicated that female rats exposed to microplastics experienced disruptions in estrous cycles and ovarian dysfunction, which are linked to infertility in mammals.
Other research has pointed to more systemic effects of microplastics on reproductive organs. In a study published in Nature Communications, found that microplastic particles accumulated in the ovaries and testes of rats, causing inflammation and oxidative stress, which are known to impair reproductive function This suggests that microplastics not only disrupt hormonal regulation but also directly damage reproductive tissues, leading to long-term reproductive health consequences.
The growing presence of microplastics in the human body raises serious health concerns, Which is why EARTHDAY.ORG is working to end plastic production. We invite you to join our fight by signing the Global Plastics Treaty petition to call on the United Nations and governments around the world to commit to a 60% reduction in all fossil fuel-based plastic production by 2040. Want to get outside and make an immediate impact? Use our Global Cleanup Map to find a cleanup near you and pick the plastic up.
